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John Fastabend [Mon, 30 Mar 2020 21:38:01 +0000 (14:38 -0700)]
bpf: Test_verifier, #65 error message updates for trunc of boundary-cross
After changes to add update_reg_bounds after ALU ops and 32-bit bounds
tracking truncation of boundary crossing range will fail earlier and with
a different error message. Now the test error trace is the following
11: (17) r1 -=
2147483584
12: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0)
R1_w=invP(id=0,smin_value=-
2147483584,smax_value=63)
R10=fp0 fp-8_w=mmmmmmmm
12: (17) r1 -=
2147483584
13: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0)
R1_w=invP(id=0,
umin_value=
18446744069414584448,umax_value=
18446744071562068095,
var_off=(0xffffffff00000000; 0xffffffff))
R10=fp0 fp-8_w=mmmmmmmm
13: (77) r1 >>= 8
14: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0)
R1_w=invP(id=0,
umin_value=
72057594021150720,umax_value=
72057594029539328,
var_off=(0xffffffff000000; 0xffffff),
s32_min_value=-
16777216,s32_max_value=-1,
u32_min_value=-
16777216)
R10=fp0 fp-8_w=mmmmmmmm
14: (0f) r0 += r1
value
72057594021150720 makes map_value pointer be out of bounds
Because we have 'umin_value == umax_value' instead of previously
where 'umin_value != umax_value' we can now fail earlier noting
that pointer addition is out of bounds.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158560428103.10843.6316594510312781186.stgit@john-Precision-5820-Tower
John Fastabend [Mon, 30 Mar 2020 21:37:40 +0000 (14:37 -0700)]
bpf: Test_verifier, bpf_get_stack return value add <0
With current ALU32 subreg handling and retval refine fix from last
patches we see an expected failure in test_verifier. With verbose
verifier state being printed at each step for clarity we have the
following relavent lines [I omit register states that are not
necessarily useful to see failure cause],
#101/p bpf_get_stack return R0 within range FAIL
Failed to load prog 'Success'!
[..]
14: (85) call bpf_get_stack#67
R0_w=map_value(id=0,off=0,ks=8,vs=48,imm=0)
R3_w=inv48
15:
R0=inv(id=0,smax_value=48,var32_off=(0x0; 0xffffffff))
15: (b7) r1 = 0
16:
R0=inv(id=0,smax_value=48,var32_off=(0x0; 0xffffffff))
R1_w=inv0
16: (bf) r8 = r0
17:
R0=inv(id=0,smax_value=48,var32_off=(0x0; 0xffffffff))
R1_w=inv0
R8_w=inv(id=0,smax_value=48,var32_off=(0x0; 0xffffffff))
17: (67) r8 <<= 32
18:
R0=inv(id=0,smax_value=48,var32_off=(0x0; 0xffffffff))
R1_w=inv0
R8_w=inv(id=0,smax_value=
9223372032559808512,
umax_value=
18446744069414584320,
var_off=(0x0; 0xffffffff00000000),
s32_min_value=0,
s32_max_value=0,
u32_max_value=0,
var32_off=(0x0; 0x0))
18: (c7) r8 s>>= 32
19
R0=inv(id=0,smax_value=48,var32_off=(0x0; 0xffffffff))
R1_w=inv0
R8_w=inv(id=0,smin_value=-
2147483648,
smax_value=
2147483647,
var32_off=(0x0; 0xffffffff))
19: (cd) if r1 s< r8 goto pc+16
R0=inv(id=0,smax_value=48,var32_off=(0x0; 0xffffffff))
R1_w=inv0
R8_w=inv(id=0,smin_value=-
2147483648,
smax_value=0,
var32_off=(0x0; 0xffffffff))
20:
R0=inv(id=0,smax_value=48,var32_off=(0x0; 0xffffffff))
R1_w=inv0
R8_w=inv(id=0,smin_value=-
2147483648,
smax_value=0,
R9=inv48
20: (1f) r9 -= r8
21: (bf) r2 = r7
22:
R2_w=map_value(id=0,off=0,ks=8,vs=48,imm=0)
22: (0f) r2 += r8
value -
2147483648 makes map_value pointer be out of bounds
After call bpf_get_stack() on line 14 and some moves we have at line 16
an r8 bound with max_value 48 but an unknown min value. This is to be
expected bpf_get_stack call can only return a max of the input size but
is free to return any negative error in the 32-bit register space. The
C helper is returning an int so will use lower 32-bits.
Lines 17 and 18 clear the top 32 bits with a left/right shift but use
ARSH so we still have worst case min bound before line 19 of -
2147483648.
At this point the signed check 'r1 s< r8' meant to protect the addition
on line 22 where dst reg is a map_value pointer may very well return
true with a large negative number. Then the final line 22 will detect
this as an invalid operation and fail the program. What we want to do
is proceed only if r8 is positive non-error. So change 'r1 s< r8' to
'r1 s> r8' so that we jump if r8 is negative.
Next we will throw an error because we access past the end of the map
value. The map value size is 48 and sizeof(struct test_val) is 48 so
we walk off the end of the map value on the second call to
get bpf_get_stack(). Fix this by changing sizeof(struct test_val) to
24 by using 'sizeof(struct test_val) / 2'. After this everything passes
as expected.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158560426019.10843.3285429543232025187.stgit@john-Precision-5820-Tower
John Fastabend [Mon, 30 Mar 2020 21:37:19 +0000 (14:37 -0700)]
bpf: Test_progs, add test to catch retval refine error handling
Before this series the verifier would clamp return bounds of
bpf_get_stack() to [0, X] and this led the verifier to believe
that a JMP_JSLT 0 would be false and so would prune that path.
The result is anything hidden behind that JSLT would be unverified.
Add a test to catch this case by hiding an goto pc-1 behind the
check which will cause an infinite loop if not rejected.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158560423908.10843.11783152347709008373.stgit@john-Precision-5820-Tower
John Fastabend [Mon, 30 Mar 2020 21:36:59 +0000 (14:36 -0700)]
bpf: Verifier, refine 32bit bound in do_refine_retval_range
Further refine return values range in do_refine_retval_range by noting
these are int return types (We will assume here that int is a 32-bit type).
Two reasons to pull this out of original patch. First it makes the original
fix impossible to backport. And second I've not seen this as being problematic
in practice unlike the other case.
Fixes:
849fa50662fbc ("bpf/verifier: refine retval R0 state for bpf_get_stack helper")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158560421952.10843.12496354931526965046.stgit@john-Precision-5820-Tower
John Fastabend [Mon, 30 Mar 2020 21:36:39 +0000 (14:36 -0700)]
bpf: Verifier, do explicit ALU32 bounds tracking
It is not possible for the current verifier to track ALU32 and JMP ops
correctly. This can result in the verifier aborting with errors even though
the program should be verifiable. BPF codes that hit this can work around
it by changin int variables to 64-bit types, marking variables volatile,
etc. But this is all very ugly so it would be better to avoid these tricks.
But, the main reason to address this now is do_refine_retval_range() was
assuming return values could not be negative. Once we fixed this code that
was previously working will no longer work. See do_refine_retval_range()
patch for details. And we don't want to suddenly cause programs that used
to work to fail.
The simplest example code snippet that illustrates the problem is likely
this,
53: w8 = w0 // r8 <- [0, S32_MAX],
// w8 <- [-S32_MIN, X]
54: w8 <s 0 // r8 <- [0, U32_MAX]
// w8 <- [0, X]
The expected 64-bit and 32-bit bounds after each line are shown on the
right. The current issue is without the w* bounds we are forced to use
the worst case bound of [0, U32_MAX]. To resolve this type of case,
jmp32 creating divergent 32-bit bounds from 64-bit bounds, we add explicit
32-bit register bounds s32_{min|max}_value and u32_{min|max}_value. Then
from branch_taken logic creating new bounds we can track 32-bit bounds
explicitly.
The next case we observed is ALU ops after the jmp32,
53: w8 = w0 // r8 <- [0, S32_MAX],
// w8 <- [-S32_MIN, X]
54: w8 <s 0 // r8 <- [0, U32_MAX]
// w8 <- [0, X]
55: w8 += 1 // r8 <- [0, U32_MAX+1]
// w8 <- [0, X+1]
In order to keep the bounds accurate at this point we also need to track
ALU32 ops. To do this we add explicit ALU32 logic for each of the ALU
ops, mov, add, sub, etc.
Finally there is a question of how and when to merge bounds. The cases
enumerate here,
1. MOV ALU32 - zext 32-bit -> 64-bit
2. MOV ALU64 - copy 64-bit -> 32-bit
3. op ALU32 - zext 32-bit -> 64-bit
4. op ALU64 - n/a
5. jmp ALU32 - 64-bit: var32_off | upper_32_bits(var64_off)
6. jmp ALU64 - 32-bit: (>> (<< var64_off))
Details for each case,
For "MOV ALU32" BPF arch zero extends so we simply copy the bounds
from 32-bit into 64-bit ensuring we truncate var_off and 64-bit
bounds correctly. See zext_32_to_64.
For "MOV ALU64" copy all bounds including 32-bit into new register. If
the src register had 32-bit bounds the dst register will as well.
For "op ALU32" zero extend 32-bit into 64-bit the same as move,
see zext_32_to_64.
For "op ALU64" calculate both 32-bit and 64-bit bounds no merging
is done here. Except we have a special case. When RSH or ARSH is
done we can't simply ignore shifting bits from 64-bit reg into the
32-bit subreg. So currently just push bounds from 64-bit into 32-bit.
This will be correct in the sense that they will represent a valid
state of the register. However we could lose some accuracy if an
ARSH is following a jmp32 operation. We can handle this special
case in a follow up series.
For "jmp ALU32" mark 64-bit reg unknown and recalculate 64-bit bounds
from tnum by setting var_off to ((<<(>>var_off)) | var32_off). We
special case if 64-bit bounds has zero'd upper 32bits at which point
we can simply copy 32-bit bounds into 64-bit register. This catches
a common compiler trick where upper 32-bits are zeroed and then
32-bit ops are used followed by a 64-bit compare or 64-bit op on
a pointer. See __reg_combine_64_into_32().
For "jmp ALU64" cast the bounds of the 64bit to their 32-bit
counterpart. For example s32_min_value = (s32)reg->smin_value. For
tnum use only the lower 32bits via, (>>(<<var_off)). See
__reg_combine_64_into_32().
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158560419880.10843.11448220440809118343.stgit@john-Precision-5820-Tower
John Fastabend [Mon, 30 Mar 2020 21:36:19 +0000 (14:36 -0700)]
bpf: Verifier, do_refine_retval_range may clamp umin to 0 incorrectly
do_refine_retval_range() is called to refine return values from specified
helpers, probe_read_str and get_stack at the moment, the reasoning is
because both have a max value as part of their input arguments and
because the helper ensure the return value will not be larger than this
we can set smax values of the return register, r0.
However, the return value is a signed integer so setting umax is incorrect
It leads to further confusion when the do_refine_retval_range() then calls,
__reg_deduce_bounds() which will see a umax value as meaning the value is
unsigned and then assuming it is unsigned set the smin = umin which in this
case results in 'smin = 0' and an 'smax = X' where X is the input argument
from the helper call.
Here are the comments from _reg_deduce_bounds() on why this would be safe
to do.
/* Learn sign from unsigned bounds. Signed bounds cross the sign
* boundary, so we must be careful.
*/
if ((s64)reg->umax_value >= 0) {
/* Positive. We can't learn anything from the smin, but smax
* is positive, hence safe.
*/
reg->smin_value = reg->umin_value;
reg->smax_value = reg->umax_value = min_t(u64, reg->smax_value,
reg->umax_value);
But now we incorrectly have a return value with type int with the
signed bounds (0,X). Suppose the return value is negative, which is
possible the we have the verifier and reality out of sync. Among other
things this may result in any error handling code being falsely detected
as dead-code and removed. For instance the example below shows using
bpf_probe_read_str() causes the error path to be identified as dead
code and removed.
>From the 'llvm-object -S' dump,
r2 = 100
call 45
if r0 s< 0 goto +4
r4 = *(u32 *)(r7 + 0)
But from dump xlate
(b7) r2 = 100
(85) call bpf_probe_read_compat_str#-96768
(61) r4 = *(u32 *)(r7 +0) <-- dropped if goto
Due to verifier state after call being
R0=inv(id=0,umax_value=100,var_off=(0x0; 0x7f))
To fix omit setting the umax value because its not safe. The only
actual bounds we know is the smax. This results in the correct bounds
(SMIN, X) where X is the max length from the helper. After this the
new verifier state looks like the following after call 45.
R0=inv(id=0,smax_value=100)
Then xlated version no longer removed dead code giving the expected
result,
(b7) r2 = 100
(85) call bpf_probe_read_compat_str#-96768
(c5) if r0 s< 0x0 goto pc+4
(61) r4 = *(u32 *)(r7 +0)
Note, bpf_probe_read_* calls are root only so we wont hit this case
with non-root bpf users.
v3: comment had some documentation about meta set to null case which
is not relevant here and confusing to include in the comment.
v2 note: In original version we set msize_smax_value from check_func_arg()
and propagated this into smax of retval. The logic was smax is the bound
on the retval we set and because the type in the helper is ARG_CONST_SIZE
we know that the reg is a positive tnum_const() so umax=smax. Alexei
pointed out though this is a bit odd to read because the register in
check_func_arg() has a C type of u32 and the umax bound would be the
normally relavent bound here. Pulling in extra knowledge about future
checks makes reading the code a bit tricky. Further having a signed
meta data that can only ever be positive is also a bit odd. So dropped
the msize_smax_value metadata and made it a u64 msize_max_value to
indicate its unsigned. And additionally save bound from umax value in
check_arg_funcs which is the same as smax due to as noted above tnumx_cont
and negative check but reads better. By my analysis nothing functionally
changes in v2 but it does get easier to read so that is win.
Fixes:
849fa50662fbc ("bpf/verifier: refine retval R0 state for bpf_get_stack helper")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158560417900.10843.14351995140624628941.stgit@john-Precision-5820-Tower
KP Singh [Mon, 30 Mar 2020 20:40:59 +0000 (22:40 +0200)]
bpf, lsm: Make BPF_LSM depend on BPF_EVENTS
LSM and tracing programs share their helpers with bpf_tracing_func_proto
which is only defined (in bpf_trace.c) when BPF_EVENTS is enabled.
Instead of adding __weak symbol, make BPF_LSM depend on BPF_EVENTS so
that both tracing and LSM programs can actually share helpers.
Fixes:
fc611f47f218 ("bpf: Introduce BPF_PROG_TYPE_LSM")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200330204059.13024-1-kpsingh@chromium.org
Alexei Starovoitov [Mon, 30 Mar 2020 20:33:10 +0000 (13:33 -0700)]
Merge branch 'bpf_sk_assign'
Joe Stringer says:
====================
Introduce a new helper that allows assigning a previously-found socket
to the skb as the packet is received towards the stack, to cause the
stack to guide the packet towards that socket subject to local routing
configuration. The intention is to support TProxy use cases more
directly from eBPF programs attached at TC ingress, to simplify and
streamline Linux stack configuration in scale environments with Cilium.
Normally in ip{,6}_rcv_core(), the skb will be orphaned, dropping any
existing socket reference associated with the skb. Existing tproxy
implementations in netfilter get around this restriction by running the
tproxy logic after ip_rcv_core() in the PREROUTING table. However, this
is not an option for TC-based logic (including eBPF programs attached at
TC ingress).
This series introduces the BPF helper bpf_sk_assign() to associate the
socket with the skb on the ingress path as the packet is passed up the
stack. The initial patch in the series simply takes a reference on the
socket to ensure safety, but later patches relax this for listen
sockets.
To ensure delivery to the relevant socket, we still consult the routing
table, for full examples of how to configure see the tests in patch #5;
the simplest form of the route would look like this:
$ ip route add local default dev lo
This series is laid out as follows:
* Patch 1 extends the eBPF API to add sk_assign() and defines a new
socket free function to allow the later paths to understand when the
socket associated with the skb should be kept through receive.
* Patches 2-3 optimize the receive path to avoid taking a reference on
listener sockets during receive.
* Patches 4-5 extends the selftests with examples of the new
functionality and validation of correct behaviour.
Changes since v4:
* Fix build with CONFIG_INET disabled
* Rebase
Changes since v3:
* Use sock_gen_put() directly instead of sock_edemux() from sock_pfree()
* Commit message wording fixups
* Add acks from Martin, Lorenz
* Rebase
Changes since v2:
* Add selftests for UDP socket redirection
* Drop the early demux optimization patch (defer for more testing)
* Fix check for orphaning after TC act return
* Tidy up the tests to clean up properly and be less noisy.
Changes since v1:
* Replace the metadata_dst approach with using the skb->destructor to
determine whether the socket has been prefetched. This is much
simpler.
* Avoid taking a reference on listener sockets during receive
* Restrict assigning sockets across namespaces
* Restrict assigning SO_REUSEPORT sockets
* Fix cookie usage for socket dst check
* Rebase the tests against test_progs infrastructure
* Tidy up commit messages
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Joe Stringer [Sun, 29 Mar 2020 22:53:42 +0000 (15:53 -0700)]
selftests: bpf: Extend sk_assign tests for UDP
Add support for testing UDP sk_assign to the existing tests.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Lorenz Bauer <lmb@cloudflare.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200329225342.16317-6-joe@wand.net.nz
Lorenz Bauer [Sun, 29 Mar 2020 22:53:41 +0000 (15:53 -0700)]
selftests: bpf: Add test for sk_assign
Attach a tc direct-action classifier to lo in a fresh network
namespace, and rewrite all connection attempts to localhost:4321
to localhost:1234 (for port tests) and connections to unreachable
IPv4/IPv6 IPs to the local socket (for address tests). Includes
implementations for both TCP and UDP.
Keep in mind that both client to server and server to client traffic
passes the classifier.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200329225342.16317-5-joe@wand.net.nz
Co-authored-by: Joe Stringer <joe@wand.net.nz>
Joe Stringer [Sun, 29 Mar 2020 22:53:40 +0000 (15:53 -0700)]
bpf: Don't refcount LISTEN sockets in sk_assign()
Avoid taking a reference on listen sockets by checking the socket type
in the sk_assign and in the corresponding skb_steal_sock() code in the
the transport layer, and by ensuring that the prefetch free (sock_pfree)
function uses the same logic to check whether the socket is refcounted.
Suggested-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200329225342.16317-4-joe@wand.net.nz
Joe Stringer [Sun, 29 Mar 2020 22:53:39 +0000 (15:53 -0700)]
net: Track socket refcounts in skb_steal_sock()
Refactor the UDP/TCP handlers slightly to allow skb_steal_sock() to make
the determination of whether the socket is reference counted in the case
where it is prefetched by earlier logic such as early_demux.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200329225342.16317-3-joe@wand.net.nz
Joe Stringer [Sun, 29 Mar 2020 22:53:38 +0000 (15:53 -0700)]
bpf: Add socket assign support
Add support for TPROXY via a new bpf helper, bpf_sk_assign().
This helper requires the BPF program to discover the socket via a call
to bpf_sk*_lookup_*(), then pass this socket to the new helper. The
helper takes its own reference to the socket in addition to any existing
reference that may or may not currently be obtained for the duration of
BPF processing. For the destination socket to receive the traffic, the
traffic must be routed towards that socket via local route. The
simplest example route is below, but in practice you may want to route
traffic more narrowly (eg by CIDR):
$ ip route add local default dev lo
This patch avoids trying to introduce an extra bit into the skb->sk, as
that would require more invasive changes to all code interacting with
the socket to ensure that the bit is handled correctly, such as all
error-handling cases along the path from the helper in BPF through to
the orphan path in the input. Instead, we opt to use the destructor
variable to switch on the prefetch of the socket.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200329225342.16317-2-joe@wand.net.nz
Daniel Borkmann [Mon, 30 Mar 2020 20:38:54 +0000 (22:38 +0200)]
bpf, doc: Add John as official reviewer to BPF subsystem
We've added John Fastabend to our weekly BPF patch review rotation over
last months now where he provided excellent and timely feedback on BPF
patches. Therefore, add him to the BPF core reviewer team to the MAINTAINERS
file to reflect that.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/0e9a74933b3f21f4c5b5a3bc7f8e900b39805639.1585556231.git.daniel@iogearbox.net
KP Singh [Mon, 30 Mar 2020 14:42:46 +0000 (16:42 +0200)]
bpf: btf: Fix arg verification in btf_ctx_access()
The bounds checking for the arguments accessed in the BPF program breaks
when the expected_attach_type is not BPF_TRACE_FEXIT, BPF_LSM_MAC or
BPF_MODIFY_RETURN resulting in no check being done for the default case
(the programs which do not receive the return value of the attached
function in its arguments) when the index of the argument being accessed
is equal to the number of arguments (nr_args).
This was a result of a misplaced "else if" block introduced by the
Commit
6ba43b761c41 ("bpf: Attachment verification for
BPF_MODIFY_RETURN")
Fixes:
6ba43b761c41 ("bpf: Attachment verification for BPF_MODIFY_RETURN")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200330144246.338-1-kpsingh@chromium.org
Jann Horn [Mon, 30 Mar 2020 16:03:24 +0000 (18:03 +0200)]
bpf: Simplify reg_set_min_max_inv handling
reg_set_min_max_inv() contains exactly the same logic as reg_set_min_max(),
just flipped around. While this makes sense in a cBPF verifier (where ALU
operations are not symmetric), it does not make sense for eBPF.
Replace reg_set_min_max_inv() with a helper that flips the opcode around,
then lets reg_set_min_max() do the complicated work.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200330160324.15259-4-daniel@iogearbox.net
Jann Horn [Mon, 30 Mar 2020 16:03:23 +0000 (18:03 +0200)]
bpf: Fix tnum constraints for 32-bit comparisons
The BPF verifier tried to track values based on 32-bit comparisons by
(ab)using the tnum state via
581738a681b6 ("bpf: Provide better register
bounds after jmp32 instructions"). The idea is that after a check like
this:
if ((u32)r0 > 3)
exit
We can't meaningfully constrain the arithmetic-range-based tracking, but
we can update the tnum state to (value=0,mask=0xffff'ffff'0000'0003).
However, the implementation from
581738a681b6 didn't compute the tnum
constraint based on the fixed operand, but instead derives it from the
arithmetic-range-based tracking. This means that after the following
sequence of operations:
if (r0 >= 0x1'0000'0001)
exit
if ((u32)r0 > 7)
exit
The verifier assumed that the lower half of r0 is in the range (0, 0)
and apply the tnum constraint (value=0,mask=0xffff'ffff'0000'0000) thus
causing the overall tnum to be (value=0,mask=0x1'0000'0000), which was
incorrect. Provide a fixed implementation.
Fixes:
581738a681b6 ("bpf: Provide better register bounds after jmp32 instructions")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200330160324.15259-3-daniel@iogearbox.net
Daniel Borkmann [Mon, 30 Mar 2020 16:03:22 +0000 (18:03 +0200)]
bpf: Undo incorrect __reg_bound_offset32 handling
Anatoly has been fuzzing with kBdysch harness and reported a hang in
one of the outcomes:
0: (b7) r0 =
808464432
1: (7f) r0 >>= r0
2: (14) w0 -=
808464432
3: (07) r0 +=
808464432
4: (b7) r1 =
808464432
5: (de) if w1 s<= w0 goto pc+0
R0_w=invP(id=0,umin_value=
808464432,umax_value=
5103431727,var_off=(0x30303020;0x10000001f)) R1_w=invP808464432 R10=fp0
6: (07) r0 += -
2144337872
7: (14) w0 -= -
1607454672
8: (25) if r0 > 0x30303030 goto pc+0
R0_w=invP(id=0,umin_value=
271581184,umax_value=
271581311,var_off=(0x10300000;0x7f)) R1_w=invP808464432 R10=fp0
9: (76) if w0 s>= 0x303030 goto pc+2
12: (95) exit
from 8 to 9: safe
from 5 to 6: R0_w=invP(id=0,umin_value=
808464432,umax_value=
5103431727,var_off=(0x30303020;0x10000001f)) R1_w=invP808464432 R10=fp0
6: (07) r0 += -
2144337872
7: (14) w0 -= -
1607454672
8: (25) if r0 > 0x30303030 goto pc+0
R0_w=invP(id=0,umin_value=
271581184,umax_value=
271581311,var_off=(0x10300000;0x7f)) R1_w=invP808464432 R10=fp0
9: safe
from 8 to 9: safe
verification time 589 usec
stack depth 0
processed 17 insns (limit
1000000) [...]
The underlying program was xlated as follows:
# bpftool p d x i 9
0: (b7) r0 =
808464432
1: (7f) r0 >>= r0
2: (14) w0 -=
808464432
3: (07) r0 +=
808464432
4: (b7) r1 =
808464432
5: (de) if w1 s<= w0 goto pc+0
6: (07) r0 += -
2144337872
7: (14) w0 -= -
1607454672
8: (25) if r0 > 0x30303030 goto pc+0
9: (76) if w0 s>= 0x303030 goto pc+2
10: (05) goto pc-1
11: (05) goto pc-1
12: (95) exit
The verifier rewrote original instructions it recognized as dead code with
'goto pc-1', but reality differs from verifier simulation in that we're
actually able to trigger a hang due to hitting the 'goto pc-1' instructions.
Taking different examples to make the issue more obvious: in this example
we're probing bounds on a completely unknown scalar variable in r1:
[...]
5: R0_w=inv1 R1_w=inv(id=0) R10=fp0
5: (18) r2 = 0x4000000000
7: R0_w=inv1 R1_w=inv(id=0) R2_w=inv274877906944 R10=fp0
7: (18) r3 = 0x2000000000
9: R0_w=inv1 R1_w=inv(id=0) R2_w=inv274877906944 R3_w=inv137438953472 R10=fp0
9: (18) r4 = 0x400
11: R0_w=inv1 R1_w=inv(id=0) R2_w=inv274877906944 R3_w=inv137438953472 R4_w=inv1024 R10=fp0
11: (18) r5 = 0x200
13: R0_w=inv1 R1_w=inv(id=0) R2_w=inv274877906944 R3_w=inv137438953472 R4_w=inv1024 R5_w=inv512 R10=fp0
13: (2d) if r1 > r2 goto pc+4
R0_w=inv1 R1_w=inv(id=0,umax_value=
274877906944,var_off=(0x0; 0x7fffffffff)) R2_w=inv274877906944 R3_w=inv137438953472 R4_w=inv1024 R5_w=inv512 R10=fp0
14: R0_w=inv1 R1_w=inv(id=0,umax_value=
274877906944,var_off=(0x0; 0x7fffffffff)) R2_w=inv274877906944 R3_w=inv137438953472 R4_w=inv1024 R5_w=inv512 R10=fp0
14: (ad) if r1 < r3 goto pc+3
R0_w=inv1 R1_w=inv(id=0,umin_value=
137438953472,umax_value=
274877906944,var_off=(0x0; 0x7fffffffff)) R2_w=inv274877906944 R3_w=inv137438953472 R4_w=inv1024 R5_w=inv512 R10=fp0
15: R0=inv1 R1=inv(id=0,umin_value=
137438953472,umax_value=
274877906944,var_off=(0x0; 0x7fffffffff)) R2=inv274877906944 R3=inv137438953472 R4=inv1024 R5=inv512 R10=fp0
15: (2e) if w1 > w4 goto pc+2
R0=inv1 R1=inv(id=0,umin_value=
137438953472,umax_value=
274877906944,var_off=(0x0; 0x7f00000000)) R2=inv274877906944 R3=inv137438953472 R4=inv1024 R5=inv512 R10=fp0
16: R0=inv1 R1=inv(id=0,umin_value=
137438953472,umax_value=
274877906944,var_off=(0x0; 0x7f00000000)) R2=inv274877906944 R3=inv137438953472 R4=inv1024 R5=inv512 R10=fp0
16: (ae) if w1 < w5 goto pc+1
R0=inv1 R1=inv(id=0,umin_value=
137438953472,umax_value=
274877906944,var_off=(0x0; 0x7f00000000)) R2=inv274877906944 R3=inv137438953472 R4=inv1024 R5=inv512 R10=fp0
[...]
We're first probing lower/upper bounds via jmp64, later we do a similar
check via jmp32 and examine the resulting var_off there. After fall-through
in insn 14, we get the following bounded r1 with 0x7fffffffff unknown marked
bits in the variable section.
Thus, after knowing r1 <= 0x4000000000 and r1 >= 0x2000000000:
max: 0b100000000000000000000000000000000000000 / 0x4000000000
var: 0b111111111111111111111111111111111111111 / 0x7fffffffff
min: 0b010000000000000000000000000000000000000 / 0x2000000000
Now, in insn 15 and 16, we perform a similar probe with lower/upper bounds
in jmp32.
Thus, after knowing r1 <= 0x4000000000 and r1 >= 0x2000000000 and
w1 <= 0x400 and w1 >= 0x200:
max: 0b100000000000000000000000000000000000000 / 0x4000000000
var: 0b111111100000000000000000000000000000000 / 0x7f00000000
min: 0b010000000000000000000000000000000000000 / 0x2000000000
The lower/upper bounds haven't changed since they have high bits set in
u64 space and the jmp32 tests can only refine bounds in the low bits.
However, for the var part the expectation would have been 0x7f000007ff
or something less precise up to 0x7fffffffff. A outcome of 0x7f00000000
is not correct since it would contradict the earlier probed bounds
where we know that the result should have been in [0x200,0x400] in u32
space. Therefore, tests with such info will lead to wrong verifier
assumptions later on like falsely predicting conditional jumps to be
always taken, etc.
The issue here is that __reg_bound_offset32()'s implementation from
commit
581738a681b6 ("bpf: Provide better register bounds after jmp32
instructions") makes an incorrect range assumption:
static void __reg_bound_offset32(struct bpf_reg_state *reg)
{
u64 mask = 0xffffFFFF;
struct tnum range = tnum_range(reg->umin_value & mask,
reg->umax_value & mask);
struct tnum lo32 = tnum_cast(reg->var_off, 4);
struct tnum hi32 = tnum_lshift(tnum_rshift(reg->var_off, 32), 32);
reg->var_off = tnum_or(hi32, tnum_intersect(lo32, range));
}
In the above walk-through example, __reg_bound_offset32() as-is chose
a range after masking with 0xffffffff of [0x0,0x0] since umin:0x2000000000
and umax:0x4000000000 and therefore the lo32 part was clamped to 0x0 as
well. However, in the umin:0x2000000000 and umax:0x4000000000 range above
we'd end up with an actual possible interval of [0x0,0xffffffff] for u32
space instead.
In case of the original reproducer, the situation looked as follows at
insn 5 for r0:
[...]
5: R0_w=invP(id=0,umin_value=
808464432,umax_value=
5103431727,var_off=(0x0; 0x1ffffffff)) R1_w=invP808464432 R10=fp0
0x30303030 0x13030302f
5: (de) if w1 s<= w0 goto pc+0
R0_w=invP(id=0,umin_value=
808464432,umax_value=
5103431727,var_off=(0x30303020; 0x10000001f)) R1_w=invP808464432 R10=fp0
0x30303030 0x13030302f
[...]
After the fall-through, we similarly forced the var_off result into
the wrong range [0x30303030,0x3030302f] suggesting later on that fixed
bits must only be of 0x30303020 with 0x10000001f unknowns whereas such
assumption can only be made when both bounds in hi32 range match.
Originally, I was thinking to fix this by moving reg into a temp reg and
use proper coerce_reg_to_size() helper on the temp reg where we can then
based on that define the range tnum for later intersection:
static void __reg_bound_offset32(struct bpf_reg_state *reg)
{
struct bpf_reg_state tmp = *reg;
struct tnum lo32, hi32, range;
coerce_reg_to_size(&tmp, 4);
range = tnum_range(tmp.umin_value, tmp.umax_value);
lo32 = tnum_cast(reg->var_off, 4);
hi32 = tnum_lshift(tnum_rshift(reg->var_off, 32), 32);
reg->var_off = tnum_or(hi32, tnum_intersect(lo32, range));
}
In the case of the concrete example, this gives us a more conservative unknown
section. Thus, after knowing r1 <= 0x4000000000 and r1 >= 0x2000000000 and
w1 <= 0x400 and w1 >= 0x200:
max: 0b100000000000000000000000000000000000000 / 0x4000000000
var: 0b111111111111111111111111111111111111111 / 0x7fffffffff
min: 0b010000000000000000000000000000000000000 / 0x2000000000
However, above new __reg_bound_offset32() has no effect on refining the
knowledge of the register contents. Meaning, if the bounds in hi32 range
mismatch we'll get the identity function given the range reg spans
[0x0,0xffffffff] and we cast var_off into lo32 only to later on binary
or it again with the hi32.
Likewise, if the bounds in hi32 range match, then we mask both bounds
with 0xffffffff, use the resulting umin/umax for the range to later
intersect the lo32 with it. However, _prior_ called __reg_bound_offset()
did already such intersection on the full reg and we therefore would only
repeat the same operation on the lo32 part twice.
Given this has no effect and the original commit had false assumptions,
this patch reverts the code entirely which is also more straight forward
for stable trees: apparently
581738a681b6 got auto-selected by Sasha's
ML system and misclassified as a fix, so it got sucked into v5.4 where
it should never have landed. A revert is low-risk also from a user PoV
since it requires a recent kernel and llc to opt-into -mcpu=v3 BPF CPU
to generate jmp32 instructions. A proper bounds refinement would need a
significantly more complex approach which is currently being worked, but
no stable material [0]. Hence revert is best option for stable. After the
revert, the original reported program gets rejected as follows:
1: (7f) r0 >>= r0
2: (14) w0 -=
808464432
3: (07) r0 +=
808464432
4: (b7) r1 =
808464432
5: (de) if w1 s<= w0 goto pc+0
R0_w=invP(id=0,umin_value=
808464432,umax_value=
5103431727,var_off=(0x0; 0x1ffffffff)) R1_w=invP808464432 R10=fp0
6: (07) r0 += -
2144337872
7: (14) w0 -= -
1607454672
8: (25) if r0 > 0x30303030 goto pc+0
R0_w=invP(id=0,umax_value=
808464432,var_off=(0x0; 0x3fffffff)) R1_w=invP808464432 R10=fp0
9: (76) if w0 s>= 0x303030 goto pc+2
R0=invP(id=0,umax_value=
3158063,var_off=(0x0; 0x3fffff)) R1=invP808464432 R10=fp0
10: (30) r0 = *(u8 *)skb[
808464432]
BPF_LD_[ABS|IND] uses reserved fields
processed 11 insns (limit
1000000) [...]
[0] https://lore.kernel.org/bpf/
158507130343.15666.
8018068546764556975.stgit@john-Precision-5820-Tower/T/
Fixes:
581738a681b6 ("bpf: Provide better register bounds after jmp32 instructions")
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200330160324.15259-2-daniel@iogearbox.net
Daniel Borkmann [Sun, 29 Mar 2020 23:35:55 +0000 (01:35 +0200)]
Merge branch 'bpf-lsm'
KP Singh says:
====================
** Motivation
Google does analysis of rich runtime security data to detect and thwart
threats in real-time. Currently, this is done in custom kernel modules
but we would like to replace this with something that's upstream and
useful to others.
The current kernel infrastructure for providing telemetry (Audit, Perf
etc.) is disjoint from access enforcement (i.e. LSMs). Augmenting the
information provided by audit requires kernel changes to audit, its
policy language and user-space components. Furthermore, building a MAC
policy based on the newly added telemetry data requires changes to
various LSMs and their respective policy languages.
This patchset allows BPF programs to be attached to LSM hooks This
facilitates a unified and dynamic (not requiring re-compilation of the
kernel) audit and MAC policy.
** Why an LSM?
Linux Security Modules target security behaviours rather than the
kernel's API. For example, it's easy to miss out a newly added system
call for executing processes (eg. execve, execveat etc.) but the LSM
framework ensures that all process executions trigger the relevant hooks
irrespective of how the process was executed.
Allowing users to implement LSM hooks at runtime also benefits the LSM
eco-system by enabling a quick feedback loop from the security community
about the kind of behaviours that the LSM Framework should be targeting.
** How does it work?
The patchset introduces a new eBPF (https://docs.cilium.io/en/v1.6/bpf/)
program type BPF_PROG_TYPE_LSM which can only be attached to LSM hooks.
Loading and attachment of BPF programs requires CAP_SYS_ADMIN.
The new LSM registers nop functions (bpf_lsm_<hook_name>) as LSM hook
callbacks. Their purpose is to provide a definite point where BPF
programs can be attached as BPF_TRAMP_MODIFY_RETURN trampoline programs
for hooks that return an int, and BPF_TRAMP_FEXIT trampoline programs
for void LSM hooks.
Audit logs can be written using a format chosen by the eBPF program to
the perf events buffer or to global eBPF variables or maps and can be
further processed in user-space.
** BTF Based Design
The current design uses BTF:
* https://facebookmicrosites.github.io/bpf/blog/2018/11/14/btf-enhancement.html
* https://lwn.net/Articles/803258
which allows verifiable read-only structure accesses by field names
rather than fixed offsets. This allows accessing the hook parameters
using a dynamically created context which provides a certain degree of
ABI stability:
// Only declare the structure and fields intended to be used
// in the program
struct vm_area_struct {
unsigned long vm_start;
} __attribute__((preserve_access_index));
// Declare the eBPF program mprotect_audit which attaches to
// to the file_mprotect LSM hook and accepts three arguments.
SEC("lsm/file_mprotect")
int BPF_PROG(mprotect_audit, struct vm_area_struct *vma,
unsigned long reqprot, unsigned long prot, int ret)
{
unsigned long vm_start = vma->vm_start;
return 0;
}
By relocating field offsets, BTF makes a large portion of kernel data
structures readily accessible across kernel versions without requiring a
large corpus of BPF helper functions and requiring recompilation with
every kernel version. The BTF type information is also used by the BPF
verifier to validate memory accesses within the BPF program and also
prevents arbitrary writes to the kernel memory.
The limitations of BTF compatibility are described in BPF Co-Re
(http://vger.kernel.org/bpfconf2019_talks/bpf-core.pdf, i.e. field
renames, #defines and changes to the signature of LSM hooks). This
design imposes that the MAC policy (eBPF programs) be updated when the
inspected kernel structures change outside of BTF compatibility
guarantees. In practice, this is only required when a structure field
used by a current policy is removed (or renamed) or when the used LSM
hooks change. We expect the maintenance cost of these changes to be
acceptable as compared to the design presented in the RFC.
(https://lore.kernel.org/bpf/
20190910115527.5235-1-kpsingh@chromium.org/).
** Usage Examples
A simple example and some documentation is included in the patchset.
In order to better illustrate the capabilities of the framework some
more advanced prototype (not-ready for review) code has also been
published separately:
* Logging execution events (including environment variables and
arguments)
https://github.com/sinkap/linux-krsi/blob/patch/v1/examples/samples/bpf/lsm_audit_env.c
* Detecting deletion of running executables:
https://github.com/sinkap/linux-krsi/blob/patch/v1/examples/samples/bpf/lsm_detect_exec_unlink.c
* Detection of writes to /proc/<pid>/mem:
https://github.com/sinkap/linux-krsi/blob/patch/v1/examples/samples/bpf/lsm_audit_env.c
We have updated Google's internal telemetry infrastructure and have
started deploying this LSM on our Linux Workstations. This gives us more
confidence in the real-world applications of such a system.
** Changelog:
- v8 -> v9:
https://lore.kernel.org/bpf/
20200327192854.31150-1-kpsingh@chromium.org/
* Fixed a selftest crash when CONFIG_LSM doesn't have "bpf".
* Added James' Ack.
* Rebase.
- v7 -> v8:
https://lore.kernel.org/bpf/
20200326142823.26277-1-kpsingh@chromium.org/
* Removed CAP_MAC_ADMIN check from bpf_lsm_verify_prog. LSMs can add it
in their own bpf_prog hook. This can be revisited as a separate patch.
* Added Andrii and James' Ack/Review tags.
* Fixed an indentation issue and missing newlines in selftest error
a cases.
* Updated a comment as suggested by Alexei.
* Updated the documentation to use the newer libbpf API and some other
fixes.
* Rebase
- v6 -> v7:
https://lore.kernel.org/bpf/
20200325152629.6904-1-kpsingh@chromium.org/
* Removed __weak from the LSM attachment nops per Kees' suggestion.
Will send a separate patch (if needed) to update the noinline
definition in include/linux/compiler_attributes.h.
* waitpid to wait specifically for the forked child in selftests.
* Comment format fixes in security/... as suggested by Casey.
* Added Acks from Kees and Andrii and Casey's Reviewed-by: tags to
the respective patches.
* Rebase
- v5 -> v6:
https://lore.kernel.org/bpf/
20200323164415.12943-1-kpsingh@chromium.org/
* Updated LSM_HOOK macro to define a default value and cleaned up the
BPF LSM hook declarations.
* Added Yonghong's Acks and Kees' Reviewed-by tags.
* Simplification of the selftest code.
* Rebase and fixes suggested by Andrii and Yonghong and some other minor
fixes noticed in internal review.
- v4 -> v5:
https://lore.kernel.org/bpf/
20200220175250.10795-1-kpsingh@chromium.org/
* Removed static keys and special casing of BPF calls from the LSM
framework.
* Initialized the BPF callbacks (nops) as proper LSM hooks.
* Updated to using the newly introduced BPF_TRAMP_MODIFY_RETURN
trampolines in https://lkml.org/lkml/2020/3/4/877
* Addressed Andrii's feedback and rebased.
- v3 -> v4:
* Moved away from allocating a separate security_hook_heads and adding a
new special case for arch_prepare_bpf_trampoline to using BPF fexit
trampolines called from the right place in the LSM hook and toggled by
static keys based on the discussion in:
https://lore.kernel.org/bpf/CAG48ez25mW+_oCxgCtbiGMX07g_ph79UOJa07h=o_6B6+Q-u5g@mail.gmail.com/
* Since the code does not deal with security_hook_heads anymore, it goes
from "being a BPF LSM" to "BPF program attachment to LSM hooks".
* Added a new test case which ensures that the BPF programs' return value
is reflected by the LSM hook.
- v2 -> v3 does not change the overall design and has some minor fixes:
* LSM_ORDER_LAST is introduced to represent the behaviour of the BPF LSM
* Fixed the inadvertent clobbering of the LSM Hook error codes
* Added GPL license requirement to the commit log
* The lsm_hook_idx is now the more conventional 0-based index
* Some changes were split into a separate patch ("Load btf_vmlinux only
once per object")
https://lore.kernel.org/bpf/
20200117212825.11755-1-kpsingh@chromium.org/
* Addressed Andrii's feedback on the BTF implementation
* Documentation update for using generated vmlinux.h to simplify
programs
* Rebase
- Changes since v1:
https://lore.kernel.org/bpf/
20191220154208.15895-1-kpsingh@chromium.org
* Eliminate the requirement to maintain LSM hooks separately in
security/bpf/hooks.h Use BPF trampolines to dynamically allocate
security hooks
* Drop the use of securityfs as bpftool provides the required
introspection capabilities. Update the tests to use the bpf_skeleton
and global variables
* Use O_CLOEXEC anonymous fds to represent BPF attachment in line with
the other BPF programs with the possibility to use bpf program pinning
in the future to provide "permanent attachment".
* Drop the logic based on prog names for handling re-attachment.
* Drop bpf_lsm_event_output from this series and send it as a separate
patch.
====================
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
KP Singh [Sun, 29 Mar 2020 00:43:56 +0000 (01:43 +0100)]
bpf: lsm: Add Documentation
Document how eBPF programs (BPF_PROG_TYPE_LSM) can be loaded and
attached (BPF_LSM_MAC) to the LSM hooks.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: Florent Revest <revest@google.com>
Reviewed-by: Thomas Garnier <thgarnie@google.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Link: https://lore.kernel.org/bpf/20200329004356.27286-9-kpsingh@chromium.org
KP Singh [Sun, 29 Mar 2020 00:43:55 +0000 (01:43 +0100)]
bpf: lsm: Add selftests for BPF_PROG_TYPE_LSM
* Load/attach a BPF program that hooks to file_mprotect (int)
and bprm_committed_creds (void).
* Perform an action that triggers the hook.
* Verify if the audit event was received using the shared global
variables for the process executed.
* Verify if the mprotect returns a -EPERM.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: Florent Revest <revest@google.com>
Reviewed-by: Thomas Garnier <thgarnie@google.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200329004356.27286-8-kpsingh@chromium.org
KP Singh [Sun, 29 Mar 2020 00:43:54 +0000 (01:43 +0100)]
tools/libbpf: Add support for BPF_PROG_TYPE_LSM
Since BPF_PROG_TYPE_LSM uses the same attaching mechanism as
BPF_PROG_TYPE_TRACING, the common logic is refactored into a static
function bpf_program__attach_btf_id.
A new API call bpf_program__attach_lsm is still added to avoid userspace
conflicts if this ever changes in the future.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: Florent Revest <revest@google.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200329004356.27286-7-kpsingh@chromium.org
KP Singh [Sun, 29 Mar 2020 00:43:53 +0000 (01:43 +0100)]
bpf: lsm: Initialize the BPF LSM hooks
* The hooks are initialized using the definitions in
include/linux/lsm_hook_defs.h.
* The LSM can be enabled / disabled with CONFIG_BPF_LSM.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: Florent Revest <revest@google.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Link: https://lore.kernel.org/bpf/20200329004356.27286-6-kpsingh@chromium.org
KP Singh [Sun, 29 Mar 2020 00:43:52 +0000 (01:43 +0100)]
bpf: lsm: Implement attach, detach and execution
JITed BPF programs are dynamically attached to the LSM hooks
using BPF trampolines. The trampoline prologue generates code to handle
conversion of the signature of the hook to the appropriate BPF context.
The allocated trampoline programs are attached to the nop functions
initialized as LSM hooks.
BPF_PROG_TYPE_LSM programs must have a GPL compatible license and
and need CAP_SYS_ADMIN (required for loading eBPF programs).
Upon attachment:
* A BPF fexit trampoline is used for LSM hooks with a void return type.
* A BPF fmod_ret trampoline is used for LSM hooks which return an
int. The attached programs can override the return value of the
bpf LSM hook to indicate a MAC Policy decision.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: Florent Revest <revest@google.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Link: https://lore.kernel.org/bpf/20200329004356.27286-5-kpsingh@chromium.org
KP Singh [Sun, 29 Mar 2020 00:43:51 +0000 (01:43 +0100)]
bpf: lsm: Provide attachment points for BPF LSM programs
When CONFIG_BPF_LSM is enabled, nop functions, bpf_lsm_<hook_name>, are
generated for each LSM hook. These functions are initialized as LSM
hooks in a subsequent patch.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: Florent Revest <revest@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Link: https://lore.kernel.org/bpf/20200329004356.27286-4-kpsingh@chromium.org
KP Singh [Sun, 29 Mar 2020 00:43:50 +0000 (01:43 +0100)]
security: Refactor declaration of LSM hooks
The information about the different types of LSM hooks is scattered
in two locations i.e. union security_list_options and
struct security_hook_heads. Rather than duplicating this information
even further for BPF_PROG_TYPE_LSM, define all the hooks with the
LSM_HOOK macro in lsm_hook_defs.h which is then used to generate all
the data structures required by the LSM framework.
The LSM hooks are defined as:
LSM_HOOK(<return_type>, <default_value>, <hook_name>, args...)
with <default_value> acccessible in security.c as:
LSM_RET_DEFAULT(<hook_name>)
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: Florent Revest <revest@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Link: https://lore.kernel.org/bpf/20200329004356.27286-3-kpsingh@chromium.org
KP Singh [Sun, 29 Mar 2020 00:43:49 +0000 (01:43 +0100)]
bpf: Introduce BPF_PROG_TYPE_LSM
Introduce types and configs for bpf programs that can be attached to
LSM hooks. The programs can be enabled by the config option
CONFIG_BPF_LSM.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Brendan Jackman <jackmanb@google.com>
Reviewed-by: Florent Revest <revest@google.com>
Reviewed-by: Thomas Garnier <thgarnie@google.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Link: https://lore.kernel.org/bpf/20200329004356.27286-2-kpsingh@chromium.org
Toke Høiland-Jørgensen [Sun, 29 Mar 2020 13:22:53 +0000 (15:22 +0200)]
selftests: Add test for overriding global data value before load
This adds a test to exercise the new bpf_map__set_initial_value() function.
The test simply overrides the global data section with all zeroes, and
checks that the new value makes it into the kernel map on load.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200329132253.232541-2-toke@redhat.com
Toke Høiland-Jørgensen [Sun, 29 Mar 2020 13:22:52 +0000 (15:22 +0200)]
libbpf: Add setter for initial value for internal maps
For internal maps (most notably the maps backing global variables), libbpf
uses an internal mmaped area to store the data after opening the object.
This data is subsequently copied into the kernel map when the object is
loaded.
This adds a function to set a new value for that data, which can be used to
before it is loaded into the kernel. This is especially relevant for RODATA
maps, since those are frozen on load.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200329132253.232541-1-toke@redhat.com
Daniel Borkmann [Sun, 29 Mar 2020 19:59:02 +0000 (21:59 +0200)]
bpf, net: Fix build issue when net ns not configured
Fix a redefinition of 'net_gen_cookie' error that was overlooked
when net ns is not configured.
Fixes:
f318903c0bf4 ("bpf: Add netns cookie and enable it for bpf cgroup hooks")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Alexei Starovoitov [Sat, 28 Mar 2020 21:24:41 +0000 (14:24 -0700)]
Merge branch 'ifla_xdp_expected_fd'
Toke Høiland-Jørgensen says:
====================
This series adds support for atomically replacing the XDP program loaded on an
interface. This is achieved by means of a new netlink attribute that can specify
the expected previous program to replace on the interface. If set, the kernel
will compare this "expected fd" attribute with the program currently loaded on
the interface, and reject the operation if it does not match.
With this primitive, userspace applications can avoid stepping on each other's
toes when simultaneously updating the loaded XDP program.
Changelog:
v4:
- Switch back to passing FD instead of ID (Andrii)
- Rename flag to XDP_FLAGS_REPLACE (for consistency with other similar uses)
v3:
- Pass existing ID instead of FD (Jakub)
- Use opts struct for new libbpf function (Andrii)
v2:
- Fix checkpatch nits and add .strict_start_type to netlink policy (Jakub)
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Toke Høiland-Jørgensen [Wed, 25 Mar 2020 17:23:29 +0000 (18:23 +0100)]
selftests/bpf: Add tests for attaching XDP programs
This adds tests for the various replacement operations using
IFLA_XDP_EXPECTED_FD.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158515700967.92963.15098921624731968356.stgit@toke.dk
Toke Høiland-Jørgensen [Wed, 25 Mar 2020 17:23:28 +0000 (18:23 +0100)]
libbpf: Add function to set link XDP fd while specifying old program
This adds a new function to set the XDP fd while specifying the FD of the
program to replace, using the newly added IFLA_XDP_EXPECTED_FD netlink
parameter. The new function uses the opts struct mechanism to be extendable
in the future.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158515700857.92963.7052131201257841700.stgit@toke.dk
Toke Høiland-Jørgensen [Wed, 25 Mar 2020 17:23:27 +0000 (18:23 +0100)]
tools: Add EXPECTED_FD-related definitions in if_link.h
This adds the IFLA_XDP_EXPECTED_FD netlink attribute definition and the
XDP_FLAGS_REPLACE flag to if_link.h in tools/include.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158515700747.92963.8615391897417388586.stgit@toke.dk
Toke Høiland-Jørgensen [Wed, 25 Mar 2020 17:23:26 +0000 (18:23 +0100)]
xdp: Support specifying expected existing program when attaching XDP
While it is currently possible for userspace to specify that an existing
XDP program should not be replaced when attaching to an interface, there is
no mechanism to safely replace a specific XDP program with another.
This patch adds a new netlink attribute, IFLA_XDP_EXPECTED_FD, which can be
set along with IFLA_XDP_FD. If set, the kernel will check that the program
currently loaded on the interface matches the expected one, and fail the
operation if it does not. This corresponds to a 'cmpxchg' memory operation.
Setting the new attribute with a negative value means that no program is
expected to be attached, which corresponds to setting the UPDATE_IF_NOEXIST
flag.
A new companion flag, XDP_FLAGS_REPLACE, is also added to explicitly
request checking of the EXPECTED_FD attribute. This is needed for userspace
to discover whether the kernel supports the new attribute.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/bpf/158515700640.92963.3551295145441017022.stgit@toke.dk
Jean-Philippe Menil [Fri, 27 Mar 2020 20:47:13 +0000 (21:47 +0100)]
bpf: Fix build warning regarding missing prototypes
Fix build warnings when building net/bpf/test_run.o with W=1 due
to missing prototype for bpf_fentry_test{1..6}.
Instead of declaring prototypes, turn off warnings with
__diag_{push,ignore,pop} as pointed out by Alexei.
Signed-off-by: Jean-Philippe Menil <jpmenil@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200327204713.28050-1-jpmenil@gmail.com
Fletcher Dunn [Fri, 27 Mar 2020 03:24:07 +0000 (03:24 +0000)]
libbpf, xsk: Init all ring members in xsk_umem__create and xsk_socket__create
Fix a sharp edge in xsk_umem__create and xsk_socket__create. Almost all of
the members of the ring buffer structs are initialized, but the "cached_xxx"
variables are not all initialized. The caller is required to zero them.
This is needlessly dangerous. The results if you don't do it can be very bad.
For example, they can cause xsk_prod_nb_free and xsk_cons_nb_avail to return
values greater than the size of the queue. xsk_ring_cons__peek can return an
index that does not refer to an item that has been queued.
I have confirmed that without this change, my program misbehaves unless I
memset the ring buffers to zero before calling the function. Afterwards,
my program works without (or with) the memset.
Signed-off-by: Fletcher Dunn <fletcherd@valvesoftware.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/85f12913cde94b19bfcb598344701c38@valvesoftware.com
Alexei Starovoitov [Sat, 28 Mar 2020 02:40:39 +0000 (19:40 -0700)]
Merge branch 'cgroup-helpers'
Daniel Borkmann says:
====================
This adds various straight-forward helper improvements and additions to BPF
cgroup based connect(), sendmsg(), recvmsg() and bind-related hooks which
would allow to implement more fine-grained policies and improve current load
balancer limitations we're seeing. For details please see individual patches.
I've tested them on Kubernetes & Cilium and also added selftests for the small
verifier extension. Thanks!
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Daniel Borkmann [Fri, 27 Mar 2020 15:58:56 +0000 (16:58 +0100)]
bpf: Add selftest cases for ctx_or_null argument type
Add various tests to make sure the verifier keeps catching them:
# ./test_verifier
[...]
#230/p pass ctx or null check, 1: ctx OK
#231/p pass ctx or null check, 2: null OK
#232/p pass ctx or null check, 3: 1 OK
#233/p pass ctx or null check, 4: ctx - const OK
#234/p pass ctx or null check, 5: null (connect) OK
#235/p pass ctx or null check, 6: null (bind) OK
#236/p pass ctx or null check, 7: ctx (bind) OK
#237/p pass ctx or null check, 8: null (bind) OK
[...]
Summary: 1595 PASSED, 0 SKIPPED, 0 FAILED
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/c74758d07b1b678036465ef7f068a49e9efd3548.1585323121.git.daniel@iogearbox.net
Daniel Borkmann [Fri, 27 Mar 2020 15:58:55 +0000 (16:58 +0100)]
bpf: Enable retrival of pid/tgid/comm from bpf cgroup hooks
We already have the bpf_get_current_uid_gid() helper enabled, and
given we now have perf event RB output available for connect(),
sendmsg(), recvmsg() and bind-related hooks, add a trivial change
to enable bpf_get_current_pid_tgid() and bpf_get_current_comm()
as well.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/18744744ed93c06343be8b41edcfd858706f39d7.1585323121.git.daniel@iogearbox.net
Daniel Borkmann [Fri, 27 Mar 2020 15:58:54 +0000 (16:58 +0100)]
bpf: Enable bpf cgroup hooks to retrieve cgroup v2 and ancestor id
Enable the bpf_get_current_cgroup_id() helper for connect(), sendmsg(),
recvmsg() and bind-related hooks in order to retrieve the cgroup v2
context which can then be used as part of the key for BPF map lookups,
for example. Given these hooks operate in process context 'current' is
always valid and pointing to the app that is performing mentioned
syscalls if it's subject to a v2 cgroup. Also with same motivation of
commit
7723628101aa ("bpf: Introduce bpf_skb_ancestor_cgroup_id helper")
enable retrieval of ancestor from current so the cgroup id can be used
for policy lookups which can then forbid connect() / bind(), for example.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/d2a7ef42530ad299e3cbb245e6c12374b72145ef.1585323121.git.daniel@iogearbox.net
Daniel Borkmann [Fri, 27 Mar 2020 15:58:53 +0000 (16:58 +0100)]
bpf: Allow to retrieve cgroup v1 classid from v2 hooks
Today, Kubernetes is still operating on cgroups v1, however, it is
possible to retrieve the task's classid based on 'current' out of
connect(), sendmsg(), recvmsg() and bind-related hooks for orchestrators
which attach to the root cgroup v2 hook in a mixed env like in case
of Cilium, for example, in order to then correlate certain pod traffic
and use it as part of the key for BPF map lookups.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/555e1c69db7376c0947007b4951c260e1074efc3.1585323121.git.daniel@iogearbox.net
Daniel Borkmann [Fri, 27 Mar 2020 15:58:52 +0000 (16:58 +0100)]
bpf: Add netns cookie and enable it for bpf cgroup hooks
In Cilium we're mainly using BPF cgroup hooks today in order to implement
kube-proxy free Kubernetes service translation for ClusterIP, NodePort (*),
ExternalIP, and LoadBalancer as well as HostPort mapping [0] for all traffic
between Cilium managed nodes. While this works in its current shape and avoids
packet-level NAT for inter Cilium managed node traffic, there is one major
limitation we're facing today, that is, lack of netns awareness.
In Kubernetes, the concept of Pods (which hold one or multiple containers)
has been built around network namespaces, so while we can use the global scope
of attaching to root BPF cgroup hooks also to our advantage (e.g. for exposing
NodePort ports on loopback addresses), we also have the need to differentiate
between initial network namespaces and non-initial one. For example, ExternalIP
services mandate that non-local service IPs are not to be translated from the
host (initial) network namespace as one example. Right now, we have an ugly
work-around in place where non-local service IPs for ExternalIP services are
not xlated from connect() and friends BPF hooks but instead via less efficient
packet-level NAT on the veth tc ingress hook for Pod traffic.
On top of determining whether we're in initial or non-initial network namespace
we also have a need for a socket-cookie like mechanism for network namespaces
scope. Socket cookies have the nice property that they can be combined as part
of the key structure e.g. for BPF LRU maps without having to worry that the
cookie could be recycled. We are planning to use this for our sessionAffinity
implementation for services. Therefore, add a new bpf_get_netns_cookie() helper
which would resolve both use cases at once: bpf_get_netns_cookie(NULL) would
provide the cookie for the initial network namespace while passing the context
instead of NULL would provide the cookie from the application's network namespace.
We're using a hole, so no size increase; the assignment happens only once.
Therefore this allows for a comparison on initial namespace as well as regular
cookie usage as we have today with socket cookies. We could later on enable
this helper for other program types as well as we would see need.
(*) Both externalTrafficPolicy={Local|Cluster} types
[0] https://github.com/cilium/cilium/blob/master/bpf/bpf_sock.c
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/c47d2346982693a9cf9da0e12690453aded4c788.1585323121.git.daniel@iogearbox.net
Daniel Borkmann [Fri, 27 Mar 2020 15:58:51 +0000 (16:58 +0100)]
bpf: Enable perf event rb output for bpf cgroup progs
Currently, connect(), sendmsg(), recvmsg() and bind-related hooks
are all lacking perf event rb output in order to push notifications
or monitoring events up to user space. Back in commit
a5a3a828cd00
("bpf: add perf event notificaton support for sock_ops"), I've worked
with Sowmini to enable them for sock_ops where the context part is
not used (as opposed to skbs for example where the packet data can
be appended). Make the bpf_sockopt_event_output() helper generic and
enable it for mentioned hooks.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/69c39daf87e076b31e52473c902e9bfd37559124.1585323121.git.daniel@iogearbox.net
Daniel Borkmann [Fri, 27 Mar 2020 15:58:50 +0000 (16:58 +0100)]
bpf: Enable retrieval of socket cookie for bind/post-bind hook
We currently make heavy use of the socket cookie in BPF's connect(),
sendmsg() and recvmsg() hooks for load-balancing decisions. However,
it is currently not enabled/implemented in BPF {post-}bind hooks
where it can later be used in combination for correlation in the tc
egress path, for example.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/e9d71f310715332f12d238cc650c1edc5be55119.1585323121.git.daniel@iogearbox.net
YueHaibing [Thu, 26 Mar 2020 03:16:13 +0000 (11:16 +0800)]
bpf: Remove unused vairable 'bpf_xdp_link_lops'
kernel/bpf/syscall.c:2263:34: warning: 'bpf_xdp_link_lops' defined but not used [-Wunused-const-variable=]
static const struct bpf_link_ops bpf_xdp_link_lops;
^~~~~~~~~~~~~~~~~
commit
70ed506c3bbc ("bpf: Introduce pinnable bpf_link abstraction")
involded this unused variable, remove it.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200326031613.19372-1-yuehaibing@huawei.com
Andrii Nakryiko [Wed, 25 Mar 2020 06:57:42 +0000 (23:57 -0700)]
bpf: Factor out attach_type to prog_type mapping for attach/detach
Factor out logic mapping expected program attach type to program type and
subsequent handling of program attach/detach. Also list out all supported
cgroup BPF program types explicitly to prevent accidental bugs once more
program types are added to a mapping. Do the same for prog_query API.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200325065746.640559-3-andriin@fb.com
Andrii Nakryiko [Wed, 25 Mar 2020 06:57:41 +0000 (23:57 -0700)]
bpf: Factor out cgroup storages operations
Refactor cgroup attach/detach code to abstract away common operations
performed on all types of cgroup storages. This makes high-level logic more
apparent, plus allows to reuse more code across multiple functions.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200325065746.640559-2-andriin@fb.com
John Fastabend [Tue, 24 Mar 2020 17:40:14 +0000 (10:40 -0700)]
bpf: Test_verifier, #70 error message updates for 32-bit right shift
After changes to add update_reg_bounds after ALU ops and adding ALU32
bounds tracking the error message is changed in the 32-bit right shift
tests.
Test "#70/u bounds check after 32-bit right shift with 64-bit input FAIL"
now fails with,
Unexpected error message!
EXP: R0 invalid mem access
RES: func#0 @0
7: (b7) r1 = 2
8: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=invP2 R10=fp0 fp-8_w=mmmmmmmm
8: (67) r1 <<= 31
9: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=invP4294967296 R10=fp0 fp-8_w=mmmmmmmm
9: (74) w1 >>= 31
10: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=invP0 R10=fp0 fp-8_w=mmmmmmmm
10: (14) w1 -= 2
11: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=invP4294967294 R10=fp0 fp-8_w=mmmmmmmm
11: (0f) r0 += r1
math between map_value pointer and
4294967294 is not allowed
And test "#70/p bounds check after 32-bit right shift with 64-bit input
FAIL" now fails with,
Unexpected error message!
EXP: R0 invalid mem access
RES: func#0 @0
7: (b7) r1 = 2
8: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=inv2 R10=fp0 fp-8_w=mmmmmmmm
8: (67) r1 <<= 31
9: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=inv4294967296 R10=fp0 fp-8_w=mmmmmmmm
9: (74) w1 >>= 31
10: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=inv0 R10=fp0 fp-8_w=mmmmmmmm
10: (14) w1 -= 2
11: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=inv4294967294 R10=fp0 fp-8_w=mmmmmmmm
11: (0f) r0 += r1
last_idx 11 first_idx 0
regs=2 stack=0 before 10: (14) w1 -= 2
regs=2 stack=0 before 9: (74) w1 >>= 31
regs=2 stack=0 before 8: (67) r1 <<= 31
regs=2 stack=0 before 7: (b7) r1 = 2
math between map_value pointer and
4294967294 is not allowed
Before this series we did not trip the "math between map_value pointer..."
error because check_reg_sane_offset is never called in
adjust_ptr_min_max_vals(). Instead we have a register state that looks
like this at line 11*,
11: R0_w=map_value(id=0,off=0,ks=8,vs=8,
smin_value=0,smax_value=0,
umin_value=0,umax_value=0,
var_off=(0x0; 0x0))
R1_w=invP(id=0,
smin_value=0,smax_value=
4294967295,
umin_value=0,umax_value=
4294967295,
var_off=(0xfffffffe; 0x0))
R10=fp(id=0,off=0,
smin_value=0,smax_value=0,
umin_value=0,umax_value=0,
var_off=(0x0; 0x0)) fp-8_w=mmmmmmmm
11: (0f) r0 += r1
In R1 'smin_val != smax_val' yet we have a tnum_const as seen
by 'var_off(0xfffffffe; 0x0))' with a 0x0 mask. So we hit this check
in adjust_ptr_min_max_vals()
if ((known && (smin_val != smax_val || umin_val != umax_val)) ||
smin_val > smax_val || umin_val > umax_val) {
/* Taint dst register if offset had invalid bounds derived from
* e.g. dead branches.
*/
__mark_reg_unknown(env, dst_reg);
return 0;
}
So we don't throw an error here and instead only throw an error
later in the verification when the memory access is made.
The root cause in verifier without alu32 bounds tracking is having
'umin_value = 0' and 'umax_value = U64_MAX' from BPF_SUB which we set
when 'umin_value < umax_val' here,
if (dst_reg->umin_value < umax_val) {
/* Overflow possible, we know nothing */
dst_reg->umin_value = 0;
dst_reg->umax_value = U64_MAX;
} else { ...}
Later in adjust_calar_min_max_vals we previously did a
coerce_reg_to_size() which will clamp the U64_MAX to U32_MAX by
truncating to 32bits. But either way without a call to update_reg_bounds
the less precise bounds tracking will fall out of the alu op
verification.
After latest changes we now exit adjust_scalar_min_max_vals with the
more precise umin value, due to zero extension propogating bounds from
alu32 bounds into alu64 bounds and then calling update_reg_bounds.
This then causes the verifier to trigger an earlier error and we get
the error in the output above.
This patch updates tests to reflect new error message.
* I have a local patch to print entire verifier state regardless if we
believe it is a constant so we can get a full picture of the state.
Usually if tnum_is_const() then bounds are also smin=smax, etc. but
this is not always true and is a bit subtle. Being able to see these
states helps understand dataflow imo. Let me know if we want something
similar upstream.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158507161475.15666.3061518385241144063.stgit@john-Precision-5820-Tower
John Fastabend [Tue, 24 Mar 2020 17:38:37 +0000 (10:38 -0700)]
bpf: Verifer, adjust_scalar_min_max_vals to always call update_reg_bounds()
Currently, for all op verification we call __red_deduce_bounds() and
__red_bound_offset() but we only call __update_reg_bounds() in bitwise
ops. However, we could benefit from calling __update_reg_bounds() in
BPF_ADD, BPF_SUB, and BPF_MUL cases as well.
For example, a register with state 'R1_w=invP0' when we subtract from
it,
w1 -= 2
Before coerce we will now have an smin_value=S64_MIN, smax_value=U64_MAX
and unsigned bounds umin_value=0, umax_value=U64_MAX. These will then
be clamped to S32_MIN, U32_MAX values by coerce in the case of alu32 op
as done in above example. However tnum will be a constant because the
ALU op is done on a constant.
Without update_reg_bounds() we have a scenario where tnum is a const
but our unsigned bounds do not reflect this. By calling update_reg_bounds
after coerce to 32bit we further refine the umin_value to U64_MAX in the
alu64 case or U32_MAX in the alu32 case above.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158507151689.15666.566796274289413203.stgit@john-Precision-5820-Tower
John Fastabend [Tue, 24 Mar 2020 17:38:15 +0000 (10:38 -0700)]
bpf: Verifer, refactor adjust_scalar_min_max_vals
Pull per op ALU logic into individual functions. We are about to add
u32 versions of each of these by pull them out the code gets a bit
more readable here and nicer in the next patch.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158507149518.15666.15672349629329072411.stgit@john-Precision-5820-Tower
Stanislav Fomichev [Wed, 25 Mar 2020 19:55:21 +0000 (12:55 -0700)]
libbpf: Don't allocate 16M for log buffer by default
For each prog/btf load we allocate and free 16 megs of verifier buffer.
On production systems it doesn't really make sense because the
programs/btf have gone through extensive testing and (mostly) guaranteed
to successfully load.
Let's assume successful case by default and skip buffer allocation
on the first try. If there is an error, start with BPF_LOG_BUF_SIZE
and double it on each ENOSPC iteration.
v3:
* Return -ENOMEM when can't allocate log buffer (Andrii Nakryiko)
v2:
* Don't allocate the buffer at all on the first try (Andrii Nakryiko)
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200325195521.112210-1-sdf@google.com
Tobias Klauser [Wed, 25 Mar 2020 11:36:55 +0000 (12:36 +0100)]
libbpf: Remove unused parameter `def` to get_map_field_int
Has been unused since commit
ef99b02b23ef ("libbpf: capture value in BTF
type info for BTF-defined map defs").
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200325113655.19341-1-tklauser@distanz.ch
Andrey Ignatov [Tue, 24 Mar 2020 18:51:35 +0000 (11:51 -0700)]
bpf: Document bpf_inspect drgn tool
It's a follow-up for discussion in [1].
drgn tool bpf_inspect.py was merged to drgn repo in [2]. Document it
in kernel tree to make BPF developers aware that the tool exists and
can help with getting BPF state unavailable via UAPI.
For now it's just one tool but the doc is written in a way that allows
to cover more tools in the future if needed.
Please refer to the doc itself for more details.
The patch was tested by `make htmldocs` and sanity-checking that
resulting html looks good.
v2 -> v3:
- two sections: "Description" and "Getting started" (Daniel);
- add examples in "Getting started" section (Daniel);
- add "Customization" section to show how tool can be customized.
v1 -> v2:
- better "BPF drgn tools" section (Alexei)
[1] https://lore.kernel.org/bpf/
20200228201514.GB51456@rdna-mbp/T/#mefed65e8a98116bd5d07d09a570a3eac46724951
[2] https://github.com/osandov/drgn/pull/49
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200324185135.1431038-1-rdna@fb.com
Daniel T. Lee [Sat, 21 Mar 2020 10:04:24 +0000 (19:04 +0900)]
samples, bpf: Refactor perf_event user program with libbpf bpf_link
The bpf_program__attach of libbpf(using bpf_link) is much more intuitive
than the previous method using ioctl.
bpf_program__attach_perf_event manages the enable of perf_event and
attach of BPF programs to it, so there's no neeed to do this
directly with ioctl.
In addition, bpf_link provides consistency in the use of API because it
allows disable (detach, destroy) for multiple events to be treated as
one bpf_link__destroy. Also, bpf_link__destroy manages the close() of
perf_event fd.
This commit refactors samples that attach the bpf program to perf_event
by using libbbpf instead of ioctl. Also the bpf_load in the samples were
removed and migrated to use libbbpf API.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200321100424.1593964-3-danieltimlee@gmail.com
Daniel T. Lee [Sat, 21 Mar 2020 10:04:23 +0000 (19:04 +0900)]
samples, bpf: Move read_trace_pipe to trace_helpers
To reduce the reliance of trace samples (trace*_user) on bpf_load,
move read_trace_pipe to trace_helpers. By moving this bpf_loader helper
elsewhere, trace functions can be easily migrated to libbbpf.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200321100424.1593964-2-danieltimlee@gmail.com
Martin KaFai Lau [Fri, 20 Mar 2020 15:21:07 +0000 (08:21 -0700)]
bpf: Add tests for bpf_sk_storage to bpf_tcp_ca
This patch adds test to exercise the bpf_sk_storage_get()
and bpf_sk_storage_delete() helper from the bpf_dctcp.c.
The setup and check on the sk_storage is done immediately
before and after the connect().
This patch also takes this chance to move the pthread_create()
after the connect() has been done. That will remove the need of
the "wait_thread" label.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200320152107.2169904-1-kafai@fb.com
Martin KaFai Lau [Fri, 20 Mar 2020 15:21:01 +0000 (08:21 -0700)]
bpf: Add bpf_sk_storage support to bpf_tcp_ca
This patch adds bpf_sk_storage_get() and bpf_sk_storage_delete()
helper to the bpf_tcp_ca's struct_ops. That would allow
bpf-tcp-cc to:
1) share sk private data with other bpf progs.
2) use bpf_sk_storage as a private storage for a bpf-tcp-cc
if the existing icsk_ca_priv is not big enough.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200320152101.2169498-1-kafai@fb.com
Bill Wendling [Fri, 20 Mar 2020 20:15:10 +0000 (13:15 -0700)]
selftests/bpf: Fix mix of tabs and spaces
Clang's -Wmisleading-indentation warns about misleading indentations if
there's a mixture of spaces and tabs. Remove extraneous spaces.
Signed-off-by: Bill Wendling <morbo@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200320201510.217169-1-morbo@google.com
YueHaibing [Fri, 20 Mar 2020 02:34:26 +0000 (10:34 +0800)]
bpf, tcp: Make tcp_bpf_recvmsg static
After commit
f747632b608f ("bpf: sockmap: Move generic sockmap
hooks from BPF TCP"), tcp_bpf_recvmsg() is not used out of
tcp_bpf.c, so make it static and remove it from tcp.h. Also move
it to BPF_STREAM_PARSER #ifdef to fix unused function warnings.
Fixes:
f747632b608f ("bpf: sockmap: Move generic sockmap hooks from BPF TCP")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200320023426.60684-3-yuehaibing@huawei.com
YueHaibing [Fri, 20 Mar 2020 02:34:25 +0000 (10:34 +0800)]
bpf, tcp: Fix unused function warnings
If BPF_STREAM_PARSER is not set, gcc warns:
net/ipv4/tcp_bpf.c:483:12: warning: 'tcp_bpf_sendpage' defined but not used [-Wunused-function]
net/ipv4/tcp_bpf.c:395:12: warning: 'tcp_bpf_sendmsg' defined but not used [-Wunused-function]
net/ipv4/tcp_bpf.c:13:13: warning: 'tcp_bpf_stream_read' defined but not used [-Wunused-function]
Moves the unused functions into the #ifdef CONFIG_BPF_STREAM_PARSER.
Fixes:
f747632b608f ("bpf: sockmap: Move generic sockmap hooks from BPF TCP")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Lorenz Bauer <lmb@cloudflare.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200320023426.60684-2-yuehaibing@huawei.com
Martin KaFai Lau [Wed, 18 Mar 2020 17:16:56 +0000 (10:16 -0700)]
bpftool: Add struct_ops support
This patch adds struct_ops support to the bpftool.
To recap a bit on the recent bpf_struct_ops feature on the kernel side:
It currently supports "struct tcp_congestion_ops" to be implemented
in bpf. At a high level, bpf_struct_ops is struct_ops map populated
with a number of bpf progs. bpf_struct_ops currently supports the
"struct tcp_congestion_ops". However, the bpf_struct_ops design is
generic enough that other kernel struct ops can be supported in
the future.
Although struct_ops is map+progs at a high lever, there are differences
in details. For example,
1) After registering a struct_ops, the struct_ops is held by the kernel
subsystem (e.g. tcp-cc). Thus, there is no need to pin a
struct_ops map or its progs in order to keep them around.
2) To iterate all struct_ops in a system, it iterates all maps
in type BPF_MAP_TYPE_STRUCT_OPS. BPF_MAP_TYPE_STRUCT_OPS is
the current usual filter. In the future, it may need to
filter by other struct_ops specific properties. e.g. filter by
tcp_congestion_ops or other kernel subsystem ops in the future.
3) struct_ops requires the running kernel having BTF info. That allows
more flexibility in handling other kernel structs. e.g. it can
always dump the latest bpf_map_info.
4) Also, "struct_ops" command is not intended to repeat all features
already provided by "map" or "prog". For example, if there really
is a need to pin the struct_ops map, the user can use the "map" cmd
to do that.
While the first attempt was to reuse parts from map/prog.c, it ended up
not a lot to share. The only obvious item is the map_parse_fds() but
that still requires modifications to accommodate struct_ops map specific
filtering (for the immediate and the future needs). Together with the
earlier mentioned differences, it is better to part away from map/prog.c.
The initial set of subcmds are, register, unregister, show, and dump.
For register, it registers all struct_ops maps that can be found in an
obj file. Option can be added in the future to specify a particular
struct_ops map. Also, the common bpf_tcp_cc is stateless (e.g.
bpf_cubic.c and bpf_dctcp.c). The "reuse map" feature is not
implemented in this patch and it can be considered later also.
For other subcmds, please see the man doc for details.
A sample output of dump:
[root@arch-fb-vm1 bpf]# bpftool struct_ops dump name cubic
[{
"bpf_map_info": {
"type": 26,
"id": 64,
"key_size": 4,
"value_size": 256,
"max_entries": 1,
"map_flags": 0,
"name": "cubic",
"ifindex": 0,
"btf_vmlinux_value_type_id": 18452,
"netns_dev": 0,
"netns_ino": 0,
"btf_id": 52,
"btf_key_type_id": 0,
"btf_value_type_id": 0
}
},{
"bpf_struct_ops_tcp_congestion_ops": {
"refcnt": {
"refs": {
"counter": 1
}
},
"state": "BPF_STRUCT_OPS_STATE_INUSE",
"data": {
"list": {
"next": 0,
"prev": 0
},
"key": 0,
"flags": 0,
"init": "void (struct sock *) bictcp_init/prog_id:138",
"release": "void (struct sock *) 0",
"ssthresh": "u32 (struct sock *) bictcp_recalc_ssthresh/prog_id:141",
"cong_avoid": "void (struct sock *, u32, u32) bictcp_cong_avoid/prog_id:140",
"set_state": "void (struct sock *, u8) bictcp_state/prog_id:142",
"cwnd_event": "void (struct sock *, enum tcp_ca_event) bictcp_cwnd_event/prog_id:139",
"in_ack_event": "void (struct sock *, u32) 0",
"undo_cwnd": "u32 (struct sock *) tcp_reno_undo_cwnd/prog_id:144",
"pkts_acked": "void (struct sock *, const struct ack_sample *) bictcp_acked/prog_id:143",
"min_tso_segs": "u32 (struct sock *) 0",
"sndbuf_expand": "u32 (struct sock *) 0",
"cong_control": "void (struct sock *, const struct rate_sample *) 0",
"get_info": "size_t (struct sock *, u32, int *, union tcp_cc_info *) 0",
"name": "bpf_cubic",
"owner": 0
}
}
}
]
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200318171656.129650-1-kafai@fb.com
Martin KaFai Lau [Wed, 18 Mar 2020 17:16:50 +0000 (10:16 -0700)]
bpftool: Translate prog_id to its bpf prog_name
The kernel struct_ops obj has kernel's func ptrs implemented by bpf_progs.
The bpf prog_id is stored as the value of the func ptr for introspection
purpose. In the latter patch, a struct_ops dump subcmd will be added
to introspect these func ptrs. It is desired to print the actual bpf
prog_name instead of only printing the prog_id.
Since struct_ops is the only usecase storing prog_id in the func ptr,
this patch adds a prog_id_as_func_ptr bool (default is false) to
"struct btf_dumper" in order not to mis-interpret the ptr value
for the other existing use-cases.
While printing a func_ptr as a bpf prog_name,
this patch also prefix the bpf prog_name with the ptr's func_proto.
[ Note that it is the ptr's func_proto instead of the bpf prog's
func_proto ]
It reuses the current btf_dump_func() to obtain the ptr's func_proto
string.
Here is an example from the bpf_cubic.c:
"void (struct sock *, u32, u32) bictcp_cong_avoid/prog_id:140"
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200318171650.129252-1-kafai@fb.com
Martin KaFai Lau [Wed, 18 Mar 2020 17:16:43 +0000 (10:16 -0700)]
bpftool: Print as a string for char array
A char[] is currently printed as an integer array.
This patch will print it as a string when
1) The array element type is an one byte int
2) The array element type has a BTF_INT_CHAR encoding or
the array element type's name is "char"
3) All characters is between (0x1f, 0x7f) and it is terminated
by a null character.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200318171643.129021-1-kafai@fb.com
Martin KaFai Lau [Wed, 18 Mar 2020 17:16:37 +0000 (10:16 -0700)]
bpftool: Print the enum's name instead of value
This patch prints the enum's name if there is one found in
the array of btf_enum.
The commit
9eea98497951 ("bpf: fix BTF verification of enums")
has details about an enum could have any power-of-2 size (up to 8 bytes).
This patch also takes this chance to accommodate these non 4 byte
enums.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20200318171637.128862-1-kafai@fb.com
Fangrui Song [Wed, 18 Mar 2020 22:27:46 +0000 (15:27 -0700)]
bpf: Support llvm-objcopy for vmlinux BTF
Simplify gen_btf logic to make it work with llvm-objcopy. The existing
'file format' and 'architecture' parsing logic is brittle and does not
work with llvm-objcopy/llvm-objdump.
'file format' output of llvm-objdump>=11 will match GNU objdump, but
'architecture' (bfdarch) may not.
.BTF in .tmp_vmlinux.btf is non-SHF_ALLOC. Add the SHF_ALLOC flag
because it is part of vmlinux image used for introspection. C code
can reference the section via linker script defined __start_BTF and
__stop_BTF. This fixes a small problem that previous .BTF had the
SHF_WRITE flag (objcopy -I binary -O elf* synthesized .data).
Additionally, `objcopy -I binary` synthesized symbols
_binary__btf_vmlinux_bin_start and _binary__btf_vmlinux_bin_stop (not
used elsewhere) are replaced with more commonplace __start_BTF and
__stop_BTF.
Add 2>/dev/null because GNU objcopy (but not llvm-objcopy) warns
"empty loadable segment detected at vaddr=0xffffffff81000000, is this intentional?"
We use a dd command to change the e_type field in the ELF header from
ET_EXEC to ET_REL so that lld will accept .btf.vmlinux.bin.o. Accepting
ET_EXEC as an input file is an extremely rare GNU ld feature that lld
does not intend to support, because this is error-prone.
The output section description .BTF in include/asm-generic/vmlinux.lds.h
avoids potential subtle orphan section placement issues and suppresses
--orphan-handling=warn warnings.
Fixes:
df786c9b9476 ("bpf: Force .BTF section start to zero when dumping from vmlinux")
Fixes:
cb0cc635c7a9 ("powerpc: Include .BTF section")
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Fangrui Song <maskray@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Stanislav Fomichev <sdf@google.com>
Tested-by: Andrii Nakryiko <andriin@fb.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Link: https://github.com/ClangBuiltLinux/linux/issues/871
Link: https://lore.kernel.org/bpf/20200318222746.173648-1-maskray@google.com
Wenbo Zhang [Sun, 15 Mar 2020 08:32:52 +0000 (04:32 -0400)]
bpf, libbpf: Fix ___bpf_kretprobe_args1(x) macro definition
Use PT_REGS_RC instead of PT_REGS_RET to get ret correctly.
Fixes:
df8ff35311c8 ("libbpf: Merge selftests' bpf_trace_helpers.h into libbpf's bpf_tracing.h")
Signed-off-by: Wenbo Zhang <ethercflow@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200315083252.22274-1-ethercflow@gmail.com
Andrii Nakryiko [Sat, 14 Mar 2020 01:39:32 +0000 (18:39 -0700)]
selftests/bpf: Reset process and thread affinity after each test/sub-test
Some tests and sub-tests are setting "custom" thread/process affinity and
don't reset it back. Instead of requiring each test to undo all this, ensure
that thread affinity is restored by test_progs test runner itself.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200314013932.4035712-3-andriin@fb.com
Andrii Nakryiko [Sat, 14 Mar 2020 01:39:31 +0000 (18:39 -0700)]
selftests/bpf: Fix test_progs's parsing of test numbers
When specifying disjoint set of tests, test_progs doesn't set skipped test's
array elements to false. This leads to spurious execution of tests that should
have been skipped. Fix it by explicitly initializing them to false.
Fixes:
3a516a0a3a7b ("selftests/bpf: add sub-tests support for test_progs")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200314013932.4035712-2-andriin@fb.com
Andrii Nakryiko [Sat, 14 Mar 2020 01:39:30 +0000 (18:39 -0700)]
selftests/bpf: Fix race in tcp_rtt test
Previous attempt to make tcp_rtt more robust introduced a new race, in which
server_done might be set to true before server can actually accept any
connection. Fix this by unconditionally waiting for accept(). Given socket is
non-blocking, if there are any problems with client side, it should eventually
close listening FD and let server thread exit with failure.
Fixes:
4cd729fa022c ("selftests/bpf: Make tcp_rtt test more robust to failures")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200314013932.4035712-1-andriin@fb.com
Andrii Nakryiko [Sat, 14 Mar 2020 00:27:43 +0000 (17:27 -0700)]
selftests/bpf: Fix nanosleep for real this time
Amazingly, some libc implementations don't call __NR_nanosleep syscall from
their nanosleep() APIs. Hammer it down with explicit syscall() call and never
get back to it again. Also simplify code for timespec initialization.
I verified that nanosleep is called w/ printk and in exactly same Linux image
that is used in Travis CI. So it should both sleep and call correct syscall.
v1->v2:
- math is too hard, fix usec -> nsec convertion (Martin);
- test_vmlinux has explicit nanosleep() call, convert that one as well.
Fixes:
4e1fd25d19e8 ("selftests/bpf: Fix usleep() implementation")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200314002743.3782677-1-andriin@fb.com
Andrii Nakryiko [Sat, 14 Mar 2020 00:18:34 +0000 (17:18 -0700)]
selftest/bpf: Fix compilation warning in sockmap_parse_prog.c
Remove unused len variable, which causes compilation warnings.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200314001834.3727680-1-andriin@fb.com
Jesper Dangaard Brouer [Fri, 13 Mar 2020 13:25:19 +0000 (14:25 +0100)]
sfc: fix XDP-redirect in this driver
XDP-redirect is broken in this driver sfc. XDP_REDIRECT requires
tailroom for skb_shared_info when creating an SKB based on the
redirected xdp_frame (both in cpumap and veth).
The fix requires some initial explaining. The driver uses RX page-split
when possible. It reserves the top 64 bytes in the RX-page for storing
dma_addr (struct efx_rx_page_state). It also have the XDP recommended
headroom of XDP_PACKET_HEADROOM (256 bytes). As it doesn't reserve any
tailroom, it can still fit two standard MTU (1500) frames into one page.
The sizeof struct skb_shared_info in 320 bytes. Thus drivers like ixgbe
and i40e, reduce their XDP headroom to 192 bytes, which allows them to
fit two frames with max 1536 bytes into a 4K page (192+1536+320=2048).
The fix is to reduce this drivers headroom to 128 bytes and add the 320
bytes tailroom. This account for reserved top 64 bytes in the page, and
still fit two frame in a page for normal MTUs.
We must never go below 128 bytes of headroom for XDP, as one cacheline
is for xdp_frame area and next cacheline is reserved for metadata area.
Fixes:
eb9a36be7f3e ("sfc: perform XDP processing on received packets")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alex Elder [Mon, 16 Mar 2020 22:51:21 +0000 (17:51 -0500)]
remoteproc: clean up notification config
Rearrange the config files for remoteproc and IPA to fix their
interdependencies.
First, have CONFIG_QCOM_Q6V5_MSS select QCOM_Q6V5_IPA_NOTIFY so the
notification code is built regardless of whether IPA needs it.
Next, represent QCOM_IPA as being dependent on QCOM_Q6V5_MSS rather
than setting its value to match QCOM_Q6V5_COMMON (which is selected
by QCOM_Q6V5_MSS).
Drop all dependencies from QCOM_Q6V5_IPA_NOTIFY. The notification
code will be built whenever QCOM_Q6V5_MSS is set, and it has no other
dependencies.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Madhuparna Bhowmik [Mon, 16 Mar 2020 17:13:52 +0000 (22:43 +0530)]
net: kcm: kcmproc.c: Fix RCU list suspicious usage warning
This path fixes the suspicious RCU usage warning reported by
kernel test robot.
net/kcm/kcmproc.c:#RCU-list_traversed_in_non-reader_section
There is no need to use list_for_each_entry_rcu() in
kcm_stats_seq_show() as the list is always traversed under
knet->mutex held.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Zheng Zengkai [Mon, 16 Mar 2020 13:05:24 +0000 (21:05 +0800)]
qede: remove some unused code in function qede_selftest_receive_traffic
Remove set but not used variables 'sw_comp_cons' and 'hw_comp_cons'
to fix gcc '-Wunused-but-set-variable' warning:
drivers/net/ethernet/qlogic/qede/qede_ethtool.c: In function qede_selftest_receive_traffic:
drivers/net/ethernet/qlogic/qede/qede_ethtool.c:1569:20:
warning: variable sw_comp_cons set but not used [-Wunused-but-set-variable]
drivers/net/ethernet/qlogic/qede/qede_ethtool.c: In function qede_selftest_receive_traffic:
drivers/net/ethernet/qlogic/qede/qede_ethtool.c:1569:6:
warning: variable hw_comp_cons set but not used [-Wunused-but-set-variable]
After removing 'hw_comp_cons',the memory barrier 'rmb()' and its comments become useless,
so remove them as well.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jiri Pirko [Mon, 16 Mar 2020 08:03:25 +0000 (09:03 +0100)]
net: sched: set the hw_stats_type in pedit loop
For a single pedit action, multiple offload entries may be used. Set the
hw_stats_type to all of them.
Fixes:
44f865801741 ("sched: act: allow user to specify type of HW stats for a filter")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Mon, 16 Mar 2020 09:10:10 +0000 (02:10 -0700)]
Merge branch 'net-stmmac-Use-readl_poll_timeout-to-simplify-the-code'
Dejin Zheng says:
====================
net: stmmac: Use readl_poll_timeout() to simplify the code
This patch sets just for replace the open-coded loop to the
readl_poll_timeout() helper macro for simplify the code in
stmmac driver.
v2 -> v3:
- return whatever error code by readl_poll_timeout() returned.
v1 -> v2:
- no changed. I am a newbie and sent this patch a month
ago (February 6th). So far, I have not received any comments or
suggestion. I think it may be lost somewhere in the world, so
resend it.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Dejin Zheng [Mon, 16 Mar 2020 02:32:54 +0000 (10:32 +0800)]
net: stmmac: use readl_poll_timeout() function in dwmac4_dma_reset()
The dwmac4_dma_reset() function use an open coded of readl_poll_timeout().
Replace the open coded handling with the proper function.
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Dejin Zheng [Mon, 16 Mar 2020 02:32:53 +0000 (10:32 +0800)]
net: stmmac: use readl_poll_timeout() function in init_systime()
The init_systime() function use an open coded of readl_poll_timeout().
Replace the open coded handling with the proper function.
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
YueHaibing [Sat, 14 Mar 2020 10:51:20 +0000 (18:51 +0800)]
chcr: remove set but not used variable 'status'
drivers/crypto/chelsio/chcr_ktls.c: In function chcr_ktls_cpl_set_tcb_rpl:
drivers/crypto/chelsio/chcr_ktls.c:662:11: warning:
variable status set but not used [-Wunused-but-set-variable]
commit
8a30923e1598 ("cxgb4/chcr: Save tx keys and handle HW response")
involved this unused variable, remove it.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Era Mayflower [Mon, 9 Mar 2020 19:47:02 +0000 (19:47 +0000)]
macsec: Netlink support of XPN cipher suites (IEEE 802.1AEbw)
Netlink support of extended packet number cipher suites,
allows adding and updating XPN macsec interfaces.
Added support in:
* Creating interfaces with GCM-AES-XPN-128 and GCM-AES-XPN-256 suites.
* Setting and getting 64bit packet numbers with of SAs.
* Setting (only on SA creation) and getting ssci of SAs.
* Setting salt when installing a SAK.
Added 2 cipher suite identifiers according to 802.1AE-2018 table 14-1:
* MACSEC_CIPHER_ID_GCM_AES_XPN_128
* MACSEC_CIPHER_ID_GCM_AES_XPN_256
In addition, added 2 new netlink attribute types:
* MACSEC_SA_ATTR_SSCI
* MACSEC_SA_ATTR_SALT
Depends on: macsec: Support XPN frame handling - IEEE 802.1AEbw.
Signed-off-by: Era Mayflower <mayflowerera@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Era Mayflower [Mon, 9 Mar 2020 19:47:01 +0000 (19:47 +0000)]
macsec: Support XPN frame handling - IEEE 802.1AEbw
Support extended packet number cipher suites (802.1AEbw) frames handling.
This does not include the needed netlink patches.
* Added xpn boolean field to `struct macsec_secy`.
* Added ssci field to `struct_macsec_tx_sa` (802.1AE figure 10-5).
* Added ssci field to `struct_macsec_rx_sa` (802.1AE figure 10-5).
* Added salt field to `struct macsec_key` (802.1AE 10.7 NOTE 1).
* Created pn_t type for easy access to lower and upper halves.
* Created salt_t type for easy access to the "ssci" and "pn" parts.
* Created `macsec_fill_iv_xpn` function to create IV in XPN mode.
* Support in PN recovery and preliminary replay check in XPN mode.
In addition, according to IEEE 802.1AEbw figure 10-5, the PN of incoming
frame can be 0 when XPN cipher suite is used, so fixed the function
`macsec_validate_skb` to fail on PN=0 only if XPN is off.
Signed-off-by: Era Mayflower <mayflowerera@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Mon, 16 Mar 2020 00:11:13 +0000 (17:11 -0700)]
Merge branch 'net-dsa-improve-serdes-integration'
Russell King says:
====================
net: dsa: improve serdes integration
Depends on "net: mii clause 37 helpers".
Andrew Lunn mentioned that the Serdes PCS found in Marvell DSA switches
does not automatically update the switch MACs with the link parameters.
Currently, the DSA code implements a work-around for this.
This series improves the Serdes integration, making use of the recent
phylink changes to support split MAC/PCS setups. One noticable
improvement for userspace is that ethtool can now report the link
partner's advertisement.
This repost has no changes compared to the previous posting; however,
the regression Andrew had found which exists even without this patch
set has now been fixed by Andrew and merged into the net-next tree.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Russell King [Sat, 14 Mar 2020 10:16:03 +0000 (10:16 +0000)]
net: dsa: mv88e6xxx: use PHY_DETECT in mac_link_up/mac_link_down
Use the status of the PHY_DETECT bit to determine whether we need to
force the MAC settings in mac_link_up() and mac_link_down().
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Russell King [Sat, 14 Mar 2020 10:15:58 +0000 (10:15 +0000)]
net: dsa: mv88e6xxx: remove port_link_state functions
The port_link_state method is only used by mv88e6xxx_port_setup_mac(),
which is now only called during port setup, rather than also being
called via phylink's mac_config method.
Remove this now unnecessary optimisation, which allows us to remove the
port_link_state methods as well.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Russell King [Sat, 14 Mar 2020 10:15:53 +0000 (10:15 +0000)]
net: dsa: mv88e6xxx: combine port_set_speed and port_set_duplex
Setting the speed independently of duplex makes little sense; the two
parameters result from negotiation or fixed setup, and may have inter-
dependencies. Moreover, they are always controlled via the same
register - having them split means we have to read-modify-write this
register twice.
Combine the two operations into a single port_set_speed_duplex()
operation. Not only is this more efficient, it reduces the size of the
code as well.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Russell King [Sat, 14 Mar 2020 10:15:48 +0000 (10:15 +0000)]
net: dsa: mv88e6xxx: fix Serdes link changes
phylink_mac_change() is supposed to be called with a 'false' argument
if the link has gone down since it was last reported up; this is to
ensure that link events along with renegotiation events are always
correctly reported to userspace.
Read the BMSR once when we have an interrupt, and report the link
latched status to phylink via phylink_mac_change(). phylink will deal
automatically with re-reading the link state once it has processed the
link-down event.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Russell King [Sat, 14 Mar 2020 10:15:43 +0000 (10:15 +0000)]
net: dsa: mv88e6xxx: extend phylink to Serdes PHYs
Extend the mv88e6xxx phylink implementation down to Serdes PHYs, which
handle the PCS layer of such links.
- Implement phylink PCS link state reading, so that we can provide
ethtool with the linkmodes and link speed in the expected manner.
Note: this will only be called for in-band negotiation, which is
only supported by the serdes interfaces.
- Implement phylink PCS configuration, so that the in-band AN and
advertisement can be configured.
- Implement phylink PCS negotiation restart, so that the in-band AN
can be restarted.
- Implement phylink PCS link up, so that when operating out-of-band,
the Serdes can be configured for the appropriate fixed speed mode.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Russell King [Sat, 14 Mar 2020 10:15:38 +0000 (10:15 +0000)]
net: dsa: mv88e6xxx: configure interface settings in mac_config
Only configure the interface settings in mac_config(), leaving the
speed and duplex settings to mac_link_up to deal with.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Russell King [Sat, 14 Mar 2020 10:15:33 +0000 (10:15 +0000)]
net: dsa: mv88e6xxx: use BMCR definitions for serdes control register
The SGMII/1000base-X serdes register set is a clause 22 register set
offset at 0x2000 in the PHYXS device. Rather than inventing our own
defintions, use those that already exist, and name the register
MV88E6390_SGMII_BMCR. Also remove the unused MV88E6390_SGMII_STATUS
definitions.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Russell King [Sat, 14 Mar 2020 10:15:28 +0000 (10:15 +0000)]
net: dsa: warn if phylink_mac_link_state returns error
Issue a warning to the kernel log if phylink_mac_link_state() returns
an error. This should not occur, but let's make it visible.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Mon, 16 Mar 2020 00:10:14 +0000 (17:10 -0700)]
Merge branch 'net-mii-clause-37-helpers'
Russell King says:
====================
net: mii clause 37 helpers
This is a re-post of two patches that are common to two series that
I've sent in recent weeks; I'm re-posting them separately in the hope
that they can be merged. No changes from either of the previous
postings.
These patches:
1. convert the existing (unused) mii_lpa_to_ethtool_lpa_x() function
to a linkmode variant.
2. add a helper for clause 37 advertisements, supporting both the
1000baseX and defacto 2500baseX variants. Note that ethtool does
not support half duplex for either of these, and we make no effort
to do so.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Russell King [Sat, 14 Mar 2020 10:09:58 +0000 (10:09 +0000)]
net: mii: add linkmode_adv_to_mii_adv_x()
Add a helper to convert a linkmode advertisement to a clause 37
advertisement value for 1000base-x and 2500base-x.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Russell King [Sat, 14 Mar 2020 10:09:53 +0000 (10:09 +0000)]
net: mii: convert mii_lpa_to_ethtool_lpa_x() to linkmode variant
Add a LPA to linkmode decoder for 1000BASE-X protocols; this decoder
only provides the modify semantics similar to other such decoders.
This replaces the unused mii_lpa_to_ethtool_lpa_x() helper.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexander Bersenev [Sat, 14 Mar 2020 05:33:24 +0000 (10:33 +0500)]
cdc_ncm: Fix the build warning
The ndp32->wLength is two bytes long, so replace cpu_to_le32 with cpu_to_le16.
Fixes:
0fa81b304a79 ("cdc_ncm: Implement the 32-bit version of NCM Transfer Block")
Signed-off-by: Alexander Bersenev <bay@hackerdom.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Sun, 15 Mar 2020 07:19:03 +0000 (00:19 -0700)]
Merge branch 'mptcp-simplify-mptcp_accept'
Paolo Abeni says:
====================
mptcp: simplify mptcp_accept()
Currently we allocate the MPTCP master socket at accept time.
The above makes mptcp_accept() quite complex, and requires checks is several
places for NULL MPTCP master socket.
These series simplify the MPTCP accept implementation, moving the master socket
allocation at syn-ack time, so that we drop unneeded checks with the follow-up
patch.
v1 -> v2:
- rebased on top of
2398e3991bda7caa6b112a6f650fbab92f732b91
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Paolo Abeni [Fri, 13 Mar 2020 15:52:42 +0000 (16:52 +0100)]
mptcp: drop unneeded checks
After the previous patch subflow->conn is always != NULL and
is never changed. We can drop a bunch of now unneeded checks.
v1 -> v2:
- rebased on top of commit
2398e3991bda ("mptcp: always
include dack if possible.")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Paolo Abeni [Fri, 13 Mar 2020 15:52:41 +0000 (16:52 +0100)]
mptcp: create msk early
This change moves the mptcp socket allocation from mptcp_accept() to
subflow_syn_recv_sock(), so that subflow->conn is now always set
for the non fallback scenario.
It allows cleaning up a bit mptcp_accept() reducing the additional
locking and will allow fourther cleanup in the next patch.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Dejin Zheng [Fri, 13 Mar 2020 14:42:57 +0000 (22:42 +0800)]
net: stmmac: platform: convert to devm_platform_ioremap_resource
Use devm_platform_ioremap_resource() to simplify code, which
contains platform_get_resource and devm_ioremap_resource.
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>