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Rich Felker [Sat, 13 Jun 2015 20:53:02 +0000 (20:53 +0000)]
remove cancellation points in stdio
commit
58165923890865a6ac042fafce13f440ee986fd9 added these optional
cancellation points on the basis that cancellable stdio could be
useful, to unblock threads stuck on stdio operations that will never
complete. however, the only way to ensure that cancellation can
achieve this is to violate the rules for side effects when
cancellation is acted upon, discarding knowledge of any partial data
transfer already completed. our implementation exhibited this behavior
and was thus non-conforming.
in addition to improving correctness, removing these cancellation
points moderately reduces code size, and should significantly improve
performance on i386, where sysenter/syscall instructions can be used
instead of "int $128" for non-cancellable syscalls.
Rich Felker [Sat, 13 Jun 2015 05:17:16 +0000 (05:17 +0000)]
fix idiom for setting stdio stream orientation to wide
the old idiom, f->mode |= f->mode+1, was adapted from the idiom for
setting byte orientation, f->mode |= f->mode-1, but the adaptation was
incorrect. unless the stream was alreasdy set byte-oriented, this code
incremented f->mode each time it was executed, which would eventually
lead to overflow. it could be fixed by changing it to f->mode |= 1,
but upcoming changes will require slightly more work at the time of
wide orientation, so it makes sense to just call fwide. as an
optimization in the single-character functions, fwide is only called
if the stream is not already wide-oriented.
Rich Felker [Sat, 13 Jun 2015 04:42:38 +0000 (04:42 +0000)]
add printing of null %s arguments as "(null)" in wide printf
this is undefined, but supported in our implementation of the normal
printf, so for consistency the wide variant should support it too.
Rich Felker [Sat, 13 Jun 2015 04:37:27 +0000 (04:37 +0000)]
add %m support to wide printf
Rich Felker [Thu, 11 Jun 2015 05:01:04 +0000 (05:01 +0000)]
add sh asm for vfork
Rich Felker [Wed, 10 Jun 2015 02:27:40 +0000 (02:27 +0000)]
implement arch-generic version of __unmapself
this can be used to put off writing an asm version of __unmapself for
new archs, or as a permanent solution on archs where it's not
practical or even possible to run momentarily with no stack.
the concept here is simple: the caller takes a lock on a global shared
stack and uses it to make the munmap and exit syscalls. the only trick
is unlocking, which must be done after the thread exits, and this is
achieved by using the set_tid_address syscall to have the kernel zero
and futex-wake the lock word as part of the exit syscall.
Rich Felker [Tue, 9 Jun 2015 20:30:35 +0000 (20:30 +0000)]
in malloc, refuse to use brk if it grows into stack
the linux/nommu fdpic ELF loader sets up the brk range to overlap
entirely with the main thread's stack (but growing from opposite
ends), so that the resulting failure mode for malloc is not to return
a null pointer but to start returning pointers to memory that overlaps
with the caller's stack. needless to say this extremely dangerous and
makes brk unusable.
since it's non-trivial to detect execution environments that might be
affected by this kernel bug, and since the severity of the bug makes
any sort of detection that might yield false-negatives unsafe, we
instead check the proximity of the brk to the stack pointer each time
the brk is to be expanded. both the main thread's stack (where the
real known risk lies) and the calling thread's stack are checked. an
arbitrary gap distance of 8 MB is imposed, chosen to be larger than
linux default main-thread stack reservation sizes and larger than any
reasonable stack configuration on nommu.
the effeciveness of this patch relies on an assumption that the amount
by which the brk is being grown is smaller than the gap limit, which
is always true for malloc's use of brk. reliance on this assumption is
why the check is being done in malloc-specific code and not in __brk.
Rich Felker [Tue, 9 Jun 2015 20:09:27 +0000 (20:09 +0000)]
fix spurious errors from pwd/grp functions when nscd backend is absent
for several pwd/grp functions, the only way the caller can distinguish
between a successful negative result ("no such user/group") and an
internal error is by clearing errno before the call and checking errno
afterwards. the nscd backend support code correctly simulated a
not-found response on systems where such a backend is not running, but
failed to restore errno.
this commit also fixed an outdated/incorrect comment.
Rich Felker [Sun, 7 Jun 2015 20:55:23 +0000 (20:55 +0000)]
fix regression in pre-v7 arm on kernels with kuser helper removed
the arm atomics/TLS runtime selection code is called from
__set_thread_area and depends on having libc.auxv and __hwcap
available. commit
71f099cb7db821c51d8f39dfac622c61e54d794c moved the
first call to __set_thread_area to the top of dynamic linking stage 3,
before this data is made available, causing the runtime detection code
to always see __hwcap as zero and thereby select the atomics/TLS
implementations based on kuser helper.
upcoming work on superh will use similar runtime detection.
ideally this early-init code should be cleanly refactored and shared
between the dynamic linker and static-linked startup.
Rich Felker [Sun, 7 Jun 2015 03:09:16 +0000 (03:09 +0000)]
add multiple inclusion guard to locale_impl.h
Rich Felker [Sun, 7 Jun 2015 02:59:49 +0000 (02:59 +0000)]
remove redefinition of MB_CUR_MAX in locale_impl.h
unless/until the byte-based C locale is implemented, defining
MB_CUR_MAX to 1 in the C locale is wrong. no internal code currently
uses the MB_CUR_MAX macro, but having it defined inconsistently is
error-prone. applications get the value from stdlib.h and were
unaffected.
Rich Felker [Sat, 6 Jun 2015 18:53:02 +0000 (18:53 +0000)]
make static C and C.UTF-8 locales available outside of newlocale
Rich Felker [Sat, 6 Jun 2015 18:20:30 +0000 (18:20 +0000)]
remove another invalid skip of locking in ungetwc
Rich Felker [Sat, 6 Jun 2015 18:16:22 +0000 (18:16 +0000)]
add macro version of ctype.h isascii function
presumably internal code (ungetwc and fputwc) was written assuming a
macro implementation existed; otherwise use of isascii is just a
pessimization.
Rich Felker [Sat, 6 Jun 2015 18:11:17 +0000 (18:11 +0000)]
remove invalid skip of locking in ungetwc
aside from being invalid, the early check only optimized the error
case, and likely pessimized the common case by separating the
two branches on isascii(c) at opposite ends of the function.
Timo Teräs [Fri, 5 Jun 2015 07:39:42 +0000 (10:39 +0300)]
fix uselocale((locale_t)0) not to modify locale
commit
68630b55c0c7219fe9df70dc28ffbf9efc8021d8 made the new locale to
be assigned unconditonally resulting in crashes later on.
Rich Felker [Thu, 4 Jun 2015 20:08:24 +0000 (16:08 -0400)]
release 1.1.10
Rich Felker [Thu, 4 Jun 2015 15:45:17 +0000 (11:45 -0400)]
fix dynamic linker regression processing R_*_NONE type relocations
commit
f3ddd173806fd5c60b3f034528ca24542aecc5b9 inadvertently removed
the early check for "none" type relocations, causing the address
dso->base+0 to be dereferenced to obtain an addend. shared libraries,
(including libc.so) and PIE executables were unaffected, since their
base addresses are the actual address of their mappings and are
readable. non-PIE main executables, however, have a base address of 0
because their load addresses are absolute and not offset at load time.
in practice none-type relocations do not arise with toolchains that
are in use except on mips, and on mips it's moderately rare for a
non-PIE executable to have a relocation table, since the mips-specific
got processing serves in its place for most purposes.
Rich Felker [Wed, 3 Jun 2015 06:00:44 +0000 (02:00 -0400)]
add additional Makefile dependency rules for rcrt1.o PIE start file
Rich Felker [Fri, 29 May 2015 03:08:12 +0000 (23:08 -0400)]
fix failure of ungetc and ungetwc to work on files in eof status
these functions were written to handle clearing eof status, but failed
to account for the __toread function's handling of eof. with this
patch applied, __toread still returns EOF when the file is in eof
status, so that read operations will fail, but it also sets up valid
buffer pointers for read mode, which are set to the end of the buffer
rather than the beginning in order to make the whole buffer available
to ungetc/ungetwc.
minor changes to __uflow were needed since it's now possible to have
non-zero buffer pointers while in eof status. as made, these changes
remove a 'fast path' bypassing the function call to __toread, which
could be reintroduced with slightly different logic, but since
ordinary files have a syscall in f->read, optimizing the code path
does not seem worthwhile.
the __stdio_read function is also updated not to zero the read buffer
pointers on eof/error. while not necessary for correctness, this
change avoids the overhead of calling __toread in ungetc after
reaching eof, and it also reduces code size and increases consistency
with the fmemopen read operation which does not zero the pointers.
Rich Felker [Thu, 28 May 2015 19:37:23 +0000 (15:37 -0400)]
add missing legacy LFS64 macros in sys/resource.h
based on patch by Felix Janda, with RLIM64_SAVED_CUR and
RLIM64_SAVED_MAX added for completeness.
Shiz [Thu, 28 May 2015 03:52:22 +0000 (05:52 +0200)]
configure: work around compilers that merely warn for unknown options
some compilers (such as clang) accept unknown options without error,
but then print warnings on each invocation, cluttering the build
output and burying meaningful warnings. this patch makes configure's
tryflag and tryldflag functions use additional options to turn the
unknown-option warnings into errors, if available, but only at check
time. these options are not output in config.mak to avoid the risk of
spurious build breakage; if they work, they will have already done
their job at configure time.
Rich Felker [Wed, 27 May 2015 19:54:47 +0000 (15:54 -0400)]
implement fail-safe static locales for newlocale
this frees applications which need to make temporary use of the C
locale (via uselocale) from the possibility that newlocale might fail.
the C.UTF-8 locale is also provided as a static locale. presently they
behave the same, but this may change in the future.
Rich Felker [Wed, 27 May 2015 07:32:46 +0000 (03:32 -0400)]
rename internal locale file handling locale maps
since the __setlocalecat function was removed, the filename
__setlocalecat.c no longer made sense.
Rich Felker [Wed, 27 May 2015 07:22:52 +0000 (03:22 -0400)]
overhaul locale internals to treat categories roughly uniformly
previously, LC_MESSAGES was treated specially as the only category
which could be set to a locale name without a definition file, in
order to facilitate gettext message translations when no libc locale
was available. LC_NUMERIC was completely un-settable, and LC_CTYPE
stored a flag intended to be used for a possible future byte-based C
locale, instead of storing a __locale_map pointer like the other
categories use.
this patch changes all categories to be represented by pointers to
__locale_map structures, and allows locale names without definition
files to be treated as valid locales with trivial definition when used
in any category. outwardly visible functional changes should be minor,
limited mainly to the strings read back from setlocale and the way
gettext handles translations in categories other than LC_MESSAGES.
various internal refactoring has also been performed, and improvements
in const correctness have been made.
Rich Felker [Wed, 27 May 2015 04:22:43 +0000 (00:22 -0400)]
replace atomics with locks in locale-setting code
this is part of a general program of removing direct use of atomics
where they are not necessary to meet correctness or performance needs,
but in this case it's also an optimization. only the global locale
needs synchronization; allocated locales referenced with locale_t
handles are immutable during their lifetimes, and using atomics to
initialize them increases their cost of setup.
Rich Felker [Tue, 26 May 2015 07:37:41 +0000 (03:37 -0400)]
add rcrt1 start file for fully static-linked PIE
static-linked PIE files need startup code to relocate themselves, much
like the dynamic linker does. rcrt1.c reuses the code in dlstart.c,
stage 1 of the dynamic linker, which in turn reuses crt_arch.h, to
achieve static PIE with no new code. only relative relocations are
supported.
existing toolchains that don't yet support static PIE directly can be
repurposed by passing "-shared -Wl,-Bstatic -Wl,-Bsymbolic" instead of
"-static -pie" and substituting rcrt1.o in place of crt1.o.
all libraries being linked must be built as PIC/PIE; TEXTRELs are not
supported at this time.
Rich Felker [Tue, 26 May 2015 06:31:04 +0000 (02:31 -0400)]
fix incorrect application of visibility to Scrt1.o
commit
de2b67f8d41e08caa56bf6540277f6561edb647f attempted to avoid
having vis.h affect crt files, but the Makefile variable used,
CRT_LIBS, refers to the final output copies in the lib directory, not
the copies in the crt build directory, and thus the -DCRT was not
applied.
while unlikely to be noticed, this regression probably broke
production of PIE executables whose main functions are not in the
executable but rather a shared library.
Rich Felker [Tue, 26 May 2015 03:33:59 +0000 (23:33 -0400)]
reprocess all libc/ldso symbolic relocations in dynamic linking stage 3
commit
f3ddd173806fd5c60b3f034528ca24542aecc5b9 introduced early
relocations and subsequent reprocessing as part of the dynamic linker
bootstrap overhaul, to allow use of arbitrary libc functions before
the main application and libraries are loaded, but only reprocessed
GOT/PLT relocation types.
commit
c093e2e8201524db0d638920e76bcb6b1d925f3a added reprocessing of
non-GOT/PLT relocations to fix an actual regression that was observed
on powerpc, but only for RELA format tables with out-of-line addends.
REL table (inline addends at the relocation address) reprocessing is
trickier because the first relocation pass clobbers the addends.
this patch extends symbolic relocation reprocessing for libc/ldso to
support all relocation types, whether REL or RELA format tables are
used. it is believed not to alter behavior on any existing archs for
the current dynamic linker and libc code. the motivations for this
change are consistency and future-proofing. it ensures that behavior
does not differ depending on whether REL or RELA tables are used,
which could lead to undetected arch-specific bugs. it also ensures
that, if in the future code depending on additional relocation types
is added to libc.so, either at the source level or as part of the
compiler runtime that gets pulled in (for example, soft-float with TLS
for fenv), the new code will work properly.
the implementation concept is simple: stage 2 of the dynamic linker
counts the number of symbolic relocations in the libc/ldso REL table
and allocates a VLA to save their addends into; stage 3 then uses the
saved addends in place of the inline ones which were clobbered. for
stack safety, a hard limit (currently 4k) is imposed on the number of
such addends; this should be a couple orders of magnitude larger than
the actual need. this number is not a runtime variable that could
break fail-safety; it is constant for a given libc.so build.
Rich Felker [Mon, 25 May 2015 23:15:17 +0000 (19:15 -0400)]
move call to dynamic linker stage-3 into stage-2 function
this move eliminates a duplicate "by-hand" symbol lookup loop from the
stage-1 code and replaces it with a call to find_sym, which can be
used once we're in stage 2. it reduces the size of the stage 1 code,
which is helpful because stage 1 will become the crt start file for
static-PIE executables, and it will allow stage 3 to access stage 2's
automatic storage, which will be important in an upcoming commit.
Rich Felker [Mon, 25 May 2015 20:02:49 +0000 (16:02 -0400)]
mark mips crt code as code
otherwise disassemblers treat it as data.
Rich Felker [Mon, 25 May 2015 19:56:36 +0000 (15:56 -0400)]
mark mips cancellable syscall code as code
otherwise disassemblers treat it as data.
Rich Felker [Mon, 25 May 2015 04:32:37 +0000 (00:32 -0400)]
simplify/shrink relocation processing in dynamic linker stage 1
the outer-loop approach made sense when we were also processing
DT_JMPREL, which might be in REL or RELA form, to avoid major code
duplication. commit
09db855b35709aa627d7055c57a98e1e471920ab removed
processing of DT_JMPREL, and in the remaining two tables, the format
(REL or RELA) is known by the name of the table. simply writing two
versions of the loop results in smaller and simpler code.
Rich Felker [Mon, 25 May 2015 04:25:56 +0000 (00:25 -0400)]
remove processing of DT_JMPREL from dynamic linker stage 1 bootstrap
the DT_JMPREL relocation table necessarily consists entirely of
JMP_SLOT (REL_PLT in internal nomenclature) relocations, which are
symbolic; they cannot be resolved in stage 1, so there is no point in
processing them.
Rich Felker [Mon, 25 May 2015 03:03:47 +0000 (23:03 -0400)]
fix stack alignment code in mips crt_arch.h
the instruction used to align the stack, "and $sp, $sp, -8", does not
actually exist; it's expanded to 2 instructions using the 'at'
(assembler temporary) register, and thus cannot be used in a branch
delay slot. since alignment mod 16 commutes with subtracting 8, simply
swapping these two operations fixes the problem.
crt1.o was not affected because it's still being generated from a
dedicated asm source file. dlstart.lo was not affected because the
stack pointer it receives is already aligned by the kernel. but
Scrt1.o was affected in cases where the dynamic linker gave it a
misaligned stack pointer.
Rich Felker [Fri, 22 May 2015 05:50:05 +0000 (01:50 -0400)]
add .text section directive to all crt_arch.h files missing it
i386 and x86_64 versions already had the .text directive; other archs
did not. normally, top-level (file scope) __asm__ starts in the .text
section anyway, but problems were reported with some versions of
clang, and it seems preferable to set it explicitly anyway, at least
for the sake of consistency between archs.
Rich Felker [Thu, 21 May 2015 21:06:28 +0000 (17:06 -0400)]
remove outdated and misleading comment in iconv.c
the comment claimed that EUC/GBK/Big5 are not implemented, which has
been incorrect since commit
19b4a0a20efc6b9df98b6a43536ecdd628ba4643.
Rich Felker [Thu, 21 May 2015 21:01:23 +0000 (17:01 -0400)]
in iconv_open, accept "CHAR" and "" as aliases for "UTF-8"
while not a requirement, it's common convention in other iconv
implementations to accept "CHAR" as an alias for nl_langinfo(CODESET),
meaning the encoding used for char[] strings in the current locale,
and also "" as an alternate form. supporting this is not costly and
improves compatibility.
Rich Felker [Wed, 20 May 2015 04:17:35 +0000 (00:17 -0400)]
fix inconsistency in a_and and a_or argument types on x86[_64]
conceptually, and on other archs, these functions take a pointer to
int, but in the i386, x86_64, and x32 versions of atomic.h, they took
a pointer to void instead.
Bobby Bingham [Sun, 17 May 2015 18:46:38 +0000 (13:46 -0500)]
inline llsc atomics when building for sh4a
If we're building for sh4a, the compiler is already free to use
instructions only available on sh4a, so we can do the same and inline the
llsc atomics. If we're building for an older processor, we still do the
same runtime atomics selection as before.
Rich Felker [Mon, 18 May 2015 20:51:54 +0000 (16:51 -0400)]
reprocess libc/ldso RELA relocations in stage 3 of dynamic linking
this fixes a regression on powerpc that was introduced in commit
f3ddd173806fd5c60b3f034528ca24542aecc5b9. global data accesses on
powerpc seem to be using a translation-unit-local GOT filled via
R_PPC_ADDR32 relocations rather than R_PPC_GLOB_DAT. being a non-GOT
relocation type, these were not reprocessed after adding the main
application and its libraries to the chain, causing libc code not to
see copy relocations in the main program, and therefore to use the
pre-copy-relocation addresses for global data objects (like environ).
the motivation for the dynamic linker only reprocessing GOT/PLT
relocation types in stage 3 is that these types always have a zero
addend, making them safe to process again even if the storage for the
addend has been clobbered. other relocation types which can be used
for address constants in initialized data objects may have non-zero
addends which will be clobbered during the first pass of relocation
processing if they're stored inline (REL form) rather than out-of-line
(RELA form).
powerpc generally uses only RELA, so this patch is sufficient to fix
the regression in practice, but is not fully general, and would not
suffice if an alternate toolchain generated REL for powerpc.
Rich Felker [Mon, 18 May 2015 16:11:25 +0000 (12:11 -0400)]
fix null pointer dereference in dcngettext under specific conditions
if setlocale has not been called, the current locale's messages_name
may be a null pointer. the code path where it's assumed to be non-null
was only reachable if bindtextdomain had already been called, which is
normally not done in programs which do not call setlocale, so the
omitted check went unnoticed.
patch from Void Linux, with description rewritten.
Rich Felker [Sat, 16 May 2015 05:53:54 +0000 (01:53 -0400)]
eliminate costly tricks to avoid TLS access for current locale state
the code being removed used atomics to track whether any threads might
be using a locale other than the current global locale, and whether
any threads might have abstract 8-bit (non-UTF-8) LC_CTYPE active, a
feature which was never committed (still pending). the motivations
were to support early execution prior to setup of the thread pointer,
to partially support systems (ancient kernels) where thread pointer
setup is not possible, and to avoid high performance cost on archs
where accessing the thread pointer may be very slow.
since commit
19a1fe670acb3ab9ead0fe31859ca7d4fe40dd54, the thread
pointer is always available, so these hacks are no longer needed.
removing them greatly simplifies the affected code.
Rich Felker [Sat, 16 May 2015 05:15:40 +0000 (01:15 -0400)]
in i386 __set_thread_area, don't assume %gs register is initially zero
commit
f630df09b1fd954eda16e2f779da0b5ecc9d80d3 added logic to handle
the case where __set_thread_area is called more than once by reusing
the GDT slot already in the %gs register, and only setting up a new
GDT slot when %gs is zero. this created a hidden assumption that %gs
is zero when a new process image starts, which is true in practice on
Linux, but does not seem to be documented ABI, and fails to hold under
qemu app-level emulation.
while it would in theory be possible to zero %gs in the entry point
code, this code is shared between static and dynamic binaries, and
dynamic binaries must not clobber the value of %gs already setup by
the dynamic linker.
the alternative solution implemented in this commit simply uses global
data to store the GDT index that's selected. __set_thread_area should
only be called in the initial thread anyway (subsequent threads get
their thread pointer setup by __clone), but even if it were called by
another thread, it would simply read and write back the same GDT index
that was already assigned to the initial thread, and thus (in the x86
memory model) there is no data race.
Rich Felker [Thu, 14 May 2015 22:51:27 +0000 (18:51 -0400)]
make arm reloc.h CRTJMP macro compatible with thumb
compilers targeting armv7 may be configured to produce thumb2 code
instead of arm code by default, and in the future we may wish to
support targets where only the thumb instruction set is available.
the instructions this patch omits in thumb mode are needed only for
non-thumb versions of armv4 or earlier, which are not supported by any
current compilers/toolchains and thus rather pointless to have. at
some point these compatibility return sequences may be removed from
all asm source files, and in that case it would make sense to remove
them here too and remove the ifdef.
Rich Felker [Thu, 14 May 2015 22:26:16 +0000 (18:26 -0400)]
make arm crt_arch.h compatible with thumb code generation
compilers targeting armv7 may be configured to produce thumb2 code
instead of arm code by default, and in the future we may wish to
support targets where only the thumb instruction set is available.
the changes made here avoid operating directly on the sp register,
which is not possible in thumb code, and address an issue with the way
the address of _DYNAMIC is computed.
previously, the relative address of _DYNAMIC was stored with an
additional offset of -8 versus the pc-relative add instruction, since
on arm the pc register evaluates to ".+8". in thumb code, it instead
evaluates to ".+4". both are two (normal-size) instructions beyond "."
in the current execution mode, so the numbered label 2 used in the
relative address expression is simply moved two instructions ahead to
be compatible with both instruction sets.
Rich Felker [Tue, 12 May 2015 23:19:08 +0000 (19:19 -0400)]
release 1.1.9
Szabolcs Nagy [Fri, 8 May 2015 08:46:50 +0000 (09:46 +0100)]
fix netinet/ether.h for c++
Rich Felker [Wed, 6 May 2015 22:53:22 +0000 (18:53 -0400)]
fix futimes legacy function with null tv pointer
a null pointer is valid here and indicates that the current time
should be used. based on patch by Felix Janda, simplified.
Rich Felker [Wed, 6 May 2015 22:37:19 +0000 (18:37 -0400)]
fix stack protector crashes on x32 & powerpc due to misplaced TLS canary
i386, x86_64, x32, and powerpc all use TLS for stack protector canary
values in the default stack protector ABI, but the location only
matched the ABI on i386 and x86_64. on x32, the expected location for
the canary contained the tid, thus producing spurious mismatches
(resulting in process termination) upon fork. on powerpc, the expected
location contained the stdio_locks list head, so returning from a
function after calling flockfile produced spurious mismatches. in both
cases, the random canary was not present, and a predictable value was
used instead, making the stack protector hardening much less effective
than it should be.
in the current fix, the thread structure has been expanded to have
canary fields at all three possible locations, and archs that use a
non-default location must define a macro in pthread_arch.h to choose
which location is used. for most archs (which lack TLS canary ABI) the
choice does not matter.
Rich Felker [Sun, 3 May 2015 01:17:19 +0000 (21:17 -0400)]
improve iswdigit macro to diagnose errors
this is analogous to commit
2ca55a93f2a11185d72dcb69006fd2c30b5c3144
for the macros in ctype.h.
Rich Felker [Sat, 2 May 2015 16:16:57 +0000 (12:16 -0400)]
fix broken cancellation on x32 due to incorrect saved-PC offset
Rich Felker [Sat, 2 May 2015 15:57:20 +0000 (11:57 -0400)]
fix crash in x32 sigsetjmp
the 64-bit push reads not only the 32-bit return address but also the
first 32 signal mask bits. if any were nonzero, the return address
obtained will be invalid.
at some point storage of the return address should probably be moved
to follow the saved mask so that there's plenty room and the same code
can be used on x32 and regular x86_64, but for now I want a fix that
does not risk breaking x86_64, and this simple re-zeroing works.
Rich Felker [Sat, 2 May 2015 15:53:45 +0000 (11:53 -0400)]
fix x32 __set_thread_area failure due to junk in upper bits
the kernel does not properly clear the upper bits of the syscall
argument, so we have to do it before the syscall.
Rich Felker [Sat, 2 May 2015 01:22:27 +0000 (21:22 -0400)]
fix dangling pointers in x32 syscall timespec fixup code
the lifetime of compound literals is the block in which they appear.
the temporary struct __timespec_kernel objects created as compound
literals no longer existed at the time their addresses were passed to
the kernel.
Szabolcs Nagy [Tue, 21 Apr 2015 22:33:33 +0000 (22:33 +0000)]
add IPTOS_CLASS_* macros to netinet/ip.h
These macros were introduced in glibc 2.12 to follow RFC 2474 which
deprecates "IP Precedence" in favor of "Class Selector Codepoints".
Szabolcs Nagy [Tue, 21 Apr 2015 23:04:11 +0000 (23:04 +0000)]
complex: fix ctanh(+-0+i*nan) and ctanh(+-0+-i*inf)
These cases were incorrect in C11 as described by
http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1886.htm
Rich Felker [Fri, 1 May 2015 17:35:51 +0000 (13:35 -0400)]
fix integer overflow in elf.h macro SHF_EXCLUDE
Rich Felker [Fri, 1 May 2015 16:25:01 +0000 (12:25 -0400)]
fix mishandling of ENOMEM return case in internal getgrent_a function
due to an incorrect return statement in this error case, the
previously blocked cancellation state was not restored and no result
was stored. this could lead to invalid (read) accesses in the caller
resulting in crashes or nonsensical result data in the event of memory
exhaustion.
Szabolcs Nagy [Thu, 30 Apr 2015 17:50:04 +0000 (18:50 +0100)]
fix __syscall declaration with wrong visibility in syscall_arch.h
remove __syscall declaration where it is not needed (aarch64, arm,
microblaze, or1k) and add the hidden attribute where it is (mips).
Szabolcs Nagy [Thu, 30 Apr 2015 17:47:39 +0000 (18:47 +0100)]
aarch64: fix CRTJMP in reloc.h
commit
f3ddd173806fd5c60b3f034528ca24542aecc5b9 broke the build by
using "bx" instead of "br".
Rich Felker [Tue, 28 Apr 2015 00:03:28 +0000 (20:03 -0400)]
fix sh jmp_buf size to match ABI
while the sh port is still experimental and subject to ABI
instability, this is not actually an application/libc boundary ABI
change. it only affects third-party APIs where jmp_buf is used in a
shared structure at the ABI boundary, because nothing anywhere near
the end of the jmp_buf object (which includes the oversized sigset_t)
is accessed by libc.
both glibc and uclibc have 15-slot jmp_buf for sh. presumably the
smaller version was used in musl because the slots for fpu status
register and thread pointer register (gbr) were incorrect and must not
be restored by longjmp, but the size should have been preserved, as
it's generally treated as a libc-agnostic ABI property for the arch,
and having extra slots free in case we ever need them for something is
useful anyway.
Rich Felker [Mon, 27 Apr 2015 17:20:47 +0000 (13:20 -0400)]
fix name of sh crt asm directory
Rich Felker [Sat, 25 Apr 2015 02:08:49 +0000 (22:08 -0400)]
fix build regression in aarch64 sigsetjmp
at least some assembler versions do not accept the register name lr.
use the name x30 instead.
Rich Felker [Fri, 24 Apr 2015 16:09:01 +0000 (12:09 -0400)]
fix ldso name for sh-nofpu subarch
previously it was using the same name as the default ABI with hard
float (floating point args and return value in registers).
the test __SH_FPU_ANY__ || __SH4__ matches what's used in the
configure script already, and seems correct under casual review
against gcc's config/sh.h, but may need tweaks. the logic for
predefined macros for sh, and what they all mean, is very complex.
eventually this should be documented in comments here.
configure already rejects "half-hard" configurations on sh where
double=float since these do not conform to Annex F and are not
suitable for musl, so these do not need to be considered here.
Rich Felker [Fri, 24 Apr 2015 15:45:25 +0000 (11:45 -0400)]
fix build regression in sh-nofpu subarch due to missing symbol
commit
646cb9a4a04e5ed78e2dd928bf9dc6e79202f609 switched sigsetjmp to
use the new hidden ___setjmp symbol for setjmp, but the nofpu variant
of setjmp.s was not updated to match.
Rich Felker [Fri, 24 Apr 2015 15:06:11 +0000 (11:06 -0400)]
fix failure of sh reloc.h to properly detect endianness for ldso name
versions of reloc.h that rely on endian macros much include endian.h
to ensure they are available.
Rich Felker [Thu, 23 Apr 2015 22:51:02 +0000 (18:51 -0400)]
fix misalignment of dtv in static-linked programs with odd-sized TLS
both static and dynamic linked versions of the __copy_tls function
have a hidden assumption that the alignment of the beginning or end of
the memory passed is suitable for storing an array of pointers for the
dtv. pthread_create satisfies this requirement except when
libc.tls_size is misaligned, which cannot happen with dynamic linking
due to way update_tls_size computes the total size, but could happen
with static linking and odd-sized TLS.
Rich Felker [Thu, 23 Apr 2015 21:37:06 +0000 (17:37 -0400)]
remove dead store from static __init_tls
commit
dab441aea240f3b7c18a26d2ef51979ea36c301c, which made thread
pointer init mandatory for all programs, rendered this store obsolete
by removing the early-return path for static programs with no TLS.
Rich Felker [Thu, 23 Apr 2015 21:04:31 +0000 (17:04 -0400)]
make __init_tp function static when static linking
this slightly reduces the code size cost of TLS/thread-pointer for
static linking since __init_tp can be inlined into its only caller and
removed. this is analogous to the handling of __init_libc in
__libc_start_main, where the function only has external linkage when
it needs to be called from the dynamic linker.
Rich Felker [Thu, 23 Apr 2015 20:49:55 +0000 (16:49 -0400)]
add dependency of dlstart.lo on crt_arch.h to Makefile
Rich Felker [Thu, 23 Apr 2015 10:21:49 +0000 (06:21 -0400)]
fix regression in x86_64 math asm with old binutils
the implicit-operand form of fucomip is rejected by binutils 2.19 and
perhaps other versions still in use. writing both operands explicitly
fixes the issue. there is no change to the resulting output.
commit
a732e80d33b4fd6f510f7cec4f5573ef5d89bc4e was the source of this
regression.
Rich Felker [Thu, 23 Apr 2015 02:11:48 +0000 (22:11 -0400)]
fix syntax errors in configure script
Rich Felker [Wed, 22 Apr 2015 07:24:37 +0000 (03:24 -0400)]
minor optimization to pthread_spin_trylock
use CAS instead of swap since it's lighter for most archs, and keep
EBUSY in the lock value so that the old value obtained by CAS can be
used directly as the return value for pthread_spin_trylock.
Rich Felker [Wed, 22 Apr 2015 07:16:50 +0000 (03:16 -0400)]
optimize spin lock not to dirty cache line while spinning
Rich Felker [Wed, 22 Apr 2015 07:07:38 +0000 (03:07 -0400)]
in visibility preinclude, remove overrides for stdin/stdout/stderr
the motivation for this change is that the extra declaration (with or
without visibility) using "struct _IO_FILE" instead of "FILE" seems to
trigger a bug in gcc 3.x where it considers the types mismatched.
however, this change also results in slightly better code and it is
valid because (1) these three objects are constant, and (2) applying
the & operator to any of them is invalid C, since they are not even
specified to be objects. thus it does not matter if the application
and libc see different addresses for them, as long as the (initial,
unchanging) value is seen the same by both.
Rich Felker [Wed, 22 Apr 2015 06:53:41 +0000 (02:53 -0400)]
fix inconsistent visibility for __hwcap and __sysinfo symbols
these are used as hidden by asm files (and such use is the whole
reason they exist), but their actual definitions were not hidden.
Rich Felker [Wed, 22 Apr 2015 06:39:01 +0000 (02:39 -0400)]
remove additional libc struct accessor cruft
commit
f9cccfc16e58b39ee381fbdfb8688db3bb8e3555 left behind the part
in libc.c; remove it too.
Rich Felker [Wed, 22 Apr 2015 06:36:54 +0000 (02:36 -0400)]
remove useless visibility application from static-linking-only code
part of the goal here is to eliminate use of the ATTR_LIBC_VISIBILITY
macro outside of libc.h, since it was never intended to be 'public'.
Rich Felker [Wed, 22 Apr 2015 06:34:16 +0000 (02:34 -0400)]
remove libc.h dependency from otherwise-independent multibyte code
Rich Felker [Wed, 22 Apr 2015 06:21:45 +0000 (02:21 -0400)]
remove cruft for libc struct accessor function and broken visibility
these were hacks to work around toolchains that could not properly
optimize PIC accesses based on visibility and would generate GOT
lookups even for hidden data, which broke the old dynamic linker.
since commit
f3ddd173806fd5c60b3f034528ca24542aecc5b9 it no longer
matters; the dynamic linker does not assume accessibility of this data
until stage 3.
Rich Felker [Wed, 22 Apr 2015 05:41:00 +0000 (01:41 -0400)]
make configure check for visibility preinclude compatible with pcc
pcc does not search for -include relative to the working directory
unless -I. is used. rather than adding -I., which could be problematic
if there's extra junk in the top-level directory, switch back to the
old method (reverting commit
60ed988fd6c67b489d7cc186ecaa9db4e5c25b8c)
of using -include vis.h and relying on -I./src/internal being present
on the command line (which the Makefile guarantees). to fix the
breakage that was present in trycppif checks with the old method,
$CFLAGS_AUTO is removed from the command line passed to trycppif; this
is valid since $CFLAGS_AUTO should not contain options that alter
compiler semantics or ABI, only optimizations, warnings, etc.
Rich Felker [Tue, 21 Apr 2015 17:50:11 +0000 (13:50 -0400)]
fix duplocale clobbering of new locale struct with memcpy of old
when the non-stub duplocale code was added as part of the locale
framework in commit
0bc03091bb674ebb9fa6fe69e4aec1da3ac484f2, the old
code to memcpy the old locale object to the new one was left behind.
the conditional for the memcpy no longer makes sense, because the
conditions are now always-true when it's reached, and the memcpy is
wrong because it clobbers the new->messages_name pointer setup just
above.
since the messages_name and ctype_utf8 members have already been
copied, all that remains is the cat[] array. these pointers are
volatile, so using memcpy to copy them is formally wrong; use a for
loop instead.
Andre McCurdy [Tue, 21 Apr 2015 17:34:05 +0000 (10:34 -0700)]
configure: check for -march and -mtune passed via CC
Some build environments pass -march and -mtune as part of CC, therefore
update configure to check both CC and CFLAGS before making the decision
to fall back to generic -march and -mtune options for x86.
Signed-off-by: Andre McCurdy <armccurdy@gmail.com>
Rich Felker [Tue, 21 Apr 2015 17:34:58 +0000 (13:34 -0400)]
remove dead case for F_SETLKW in fcntl
the first switch already returns in the F_SETLKW code path so it need
not be handled in the second switch. moreover the code in the second
switch is wrong for the F_SETLKW command: it's not cancellable.
Rich Felker [Tue, 21 Apr 2015 17:24:46 +0000 (13:24 -0400)]
fix mmap leak in sem_open failure path for link call
the leak was found by static analysis (reported by Alexander Monakov),
not tested/observed, but seems to have occured both when failing due
to O_EXCL, and in a race condition with O_CREAT but not O_EXCL where a
semaphore by the same name was created concurrently.
Rich Felker [Tue, 21 Apr 2015 17:22:48 +0000 (13:22 -0400)]
remove always-true conditional in dynamic linker TLSDESC processing
the allocating path which can fail is for dynamic TLS, which can only
occur at runtime, and the check for runtime was already made in the
outer conditional.
Rich Felker [Tue, 21 Apr 2015 17:07:06 +0000 (13:07 -0400)]
remove redundant code in do_dlsym function
commit
637dd2d383cc1f63bf02a732f03786857b22c7bd introduced the checks
for RTLD_DEFAULT and RTLD_NEXT here, claiming they fixed a regression,
but the above conditional block clearly already covered these cases,
and removing the checks produces no difference in the generated code.
Rich Felker [Mon, 20 Apr 2015 22:17:48 +0000 (18:17 -0400)]
fix breakage in x32 dynamic linker due to mismatching register size
the jmp instruction requires a 64-bit register, so cast the desired PC
address up to uint64_t, going through uintptr_t to ensure that it's
zero-extended rather than possibly sign-extended.
Rich Felker [Mon, 20 Apr 2015 22:14:19 +0000 (18:14 -0400)]
fix regression in configure script with new visibility option
commit
de2b67f8d41e08caa56bf6540277f6561edb647f introduced a
regression by adding a -include option to CFLAGS_AUTO which did not
work without additional -I options. this broke subsequent trycppif
tests and caused x86_64 to be misdetected as x32, among other issues.
simply using the full relative pathname to vis.h rather than -I is the
cleanest way to fix the problem.
Rich Felker [Mon, 20 Apr 2015 02:05:29 +0000 (22:05 -0400)]
add optional global visibility override
this is implemented via the build system and does not affect source
files. the idea is to use protected or hidden visibility to prevent
the compiler from pessimizing function calls within a shared (or
position-independent static) libc in the form of overhead setting up
for a call through the PLT. the ld-time symbol binding via the
-Bsymbolic-functions option already optimized out the PLT itself, but
not the code in the caller needed to support a call through the PLT.
on some archs this overhead can be substantial; on others it's
trivial.
Rich Felker [Mon, 20 Apr 2015 01:49:54 +0000 (21:49 -0400)]
remove invalid PLT calls from or1k asm
analogous to commit
646cb9a4a04e5ed78e2dd928bf9dc6e79202f609 for sh.
Rich Felker [Mon, 20 Apr 2015 01:20:08 +0000 (21:20 -0400)]
remove possible-textrels from powerpc asm
these are perfectly fine with ld-time symbol binding, but otherwise
result in textrels. they cannot be replaced with @PLT jump targets
because the PLT thunks require a GOT register to be setup, so use a
hidden alias instead.
Rich Felker [Mon, 20 Apr 2015 00:56:20 +0000 (20:56 -0400)]
remove invalid PLT calls from microblaze asm
analogous to commit
646cb9a4a04e5ed78e2dd928bf9dc6e79202f609 for sh.
Rich Felker [Mon, 20 Apr 2015 00:50:03 +0000 (20:50 -0400)]
remove invalid PLT calls from sh asm
these are perfectly fine with ld-time symbol binding, but if the calls
go through a PLT thunk, they are invalid because the caller does not
setup a GOT register. use a hidden alias to bypass the issue.
Rich Felker [Sun, 19 Apr 2015 01:18:23 +0000 (21:18 -0400)]
remove potentially PIC-incompatible relocations from x86_64 and x32 asm
analogous to commit
8ed66ecbcba1dd0f899f22b534aac92a282f42d5 for i386.
Rich Felker [Sun, 19 Apr 2015 00:45:39 +0000 (20:45 -0400)]
remove the last of possible-textrels from i386 asm
none of these are actual textrels because of ld-time binding performed
by -Bsymbolic-functions, but I'm changing them with the goal of making
ld-time binding purely an optimization rather than relying on it for
semantic purposes.
in the case of memmove's call to memcpy, making it explicit that the
memmove asm is assuming the forward-copying behavior of the memcpy asm
is desirable anyway; in case memcpy is ever changed, the semantic
mismatch would be apparent while editing memmcpy.s.
Rich Felker [Sat, 18 Apr 2015 22:00:22 +0000 (18:00 -0400)]
make dlerror state and message thread-local and dynamically-allocated
this fixes truncation of error messages containing long pathnames or
symbol names.
the dlerror state was previously required by POSIX to be global. the
resolution of bug 97 relaxed the requirements to allow thread-safe
implementations of dlerror with thread-local state and message buffer.
Alexander Monakov [Tue, 14 Apr 2015 22:44:02 +0000 (01:44 +0300)]
add missing 'void' in prototypes of internal pthread functions
Szabolcs Nagy [Sat, 11 Apr 2015 00:35:07 +0000 (00:35 +0000)]
math: fix pow(+-0,-inf) not to raise divbyzero flag
this reverts the commit
f29fea00b5bc72d4b8abccba2bb1e312684d1fce
which was based on a bug in C99 and POSIX and did not match IEEE-754
http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1515.pdf