From 1e7ee04b035a268716c98a1ee22634419f30d25d Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Wed, 2 Jun 2021 11:27:49 +0800 Subject: [PATCH] bpf: Adjust F_NEEDS_EFFICIENT_UNALIGNED_ACCESS handling in test_verifier.c commit c7665702d3208b77b8e00f0699b6b88241b04360 upstream Make it set the flag argument to bpf_verify_program() which will relax the alignment restrictions. Now all such test cases will go properly through the verifier even on inefficient unaligned access architectures. On inefficient unaligned access architectures do not try to run such programs, instead mark the test case as passing but annotate the result similarly to how it is done now in the presence of this flag. So, we get complete full coverage for all REJECT test cases, and at least verifier level coverage for ACCEPT test cases. Signed-off-by: David S. Miller Signed-off-by: Alexei Starovoitov Signed-off-by: Tiezhu Yang Signed-off-by: Greg Kroah-Hartman --- tools/testing/selftests/bpf/test_verifier.c | 42 ++++++++++++++++------------- 1 file changed, 24 insertions(+), 18 deletions(-) diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c index 919f97a20203..686f5d1ac74a 100644 --- a/tools/testing/selftests/bpf/test_verifier.c +++ b/tools/testing/selftests/bpf/test_verifier.c @@ -12844,13 +12844,14 @@ out: static void do_test_single(struct bpf_test *test, bool unpriv, int *passes, int *errors) { - int fd_prog, expected_ret, reject_from_alignment; + int fd_prog, expected_ret, alignment_prevented_execution; int prog_len, prog_type = test->prog_type; struct bpf_insn *prog = test->insns; int map_fds[MAX_NR_MAPS]; const char *expected_err; uint32_t expected_val; uint32_t retval; + __u32 pflags; int i, err; for (i = 0; i < MAX_NR_MAPS; i++) @@ -12861,9 +12862,12 @@ static void do_test_single(struct bpf_test *test, bool unpriv, do_test_fixup(test, prog_type, prog, map_fds); prog_len = probe_filter_length(prog); - fd_prog = bpf_verify_program(prog_type, prog, prog_len, - test->flags & F_LOAD_WITH_STRICT_ALIGNMENT ? - BPF_F_STRICT_ALIGNMENT : 0, + pflags = 0; + if (test->flags & F_LOAD_WITH_STRICT_ALIGNMENT) + pflags |= BPF_F_STRICT_ALIGNMENT; + if (test->flags & F_NEEDS_EFFICIENT_UNALIGNED_ACCESS) + pflags |= BPF_F_ANY_ALIGNMENT; + fd_prog = bpf_verify_program(prog_type, prog, prog_len, pflags, "GPL", 0, bpf_vlog, sizeof(bpf_vlog), 1); expected_ret = unpriv && test->result_unpriv != UNDEF ? @@ -12873,28 +12877,27 @@ static void do_test_single(struct bpf_test *test, bool unpriv, expected_val = unpriv && test->retval_unpriv ? test->retval_unpriv : test->retval; - reject_from_alignment = fd_prog < 0 && - (test->flags & F_NEEDS_EFFICIENT_UNALIGNED_ACCESS) && - strstr(bpf_vlog, "misaligned"); -#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS - if (reject_from_alignment) { - printf("FAIL\nFailed due to alignment despite having efficient unaligned access: '%s'!\n", - strerror(errno)); - goto fail_log; - } -#endif + alignment_prevented_execution = 0; + if (expected_ret == ACCEPT) { - if (fd_prog < 0 && !reject_from_alignment) { + if (fd_prog < 0) { printf("FAIL\nFailed to load prog '%s'!\n", strerror(errno)); goto fail_log; } +#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS + if (fd_prog >= 0 && + (test->flags & F_NEEDS_EFFICIENT_UNALIGNED_ACCESS)) { + alignment_prevented_execution = 1; + goto test_ok; + } +#endif } else { if (fd_prog >= 0) { printf("FAIL\nUnexpected success to load!\n"); goto fail_log; } - if (!strstr(bpf_vlog, expected_err) && !reject_from_alignment) { + if (!strstr(bpf_vlog, expected_err)) { printf("FAIL\nUnexpected error message!\n\tEXP: %s\n\tRES: %s\n", expected_err, bpf_vlog); goto fail_log; @@ -12922,9 +12925,12 @@ static void do_test_single(struct bpf_test *test, bool unpriv, goto fail_log; } } +#ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS +test_ok: +#endif (*passes)++; - printf("OK%s\n", reject_from_alignment ? - " (NOTE: reject due to unknown alignment)" : ""); + printf("OK%s\n", alignment_prevented_execution ? + " (NOTE: not executed due to unknown alignment)" : ""); close_fds: close(fd_prog); for (i = 0; i < MAX_NR_MAPS; i++) -- 2.11.0