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| author |   Ilya Leoshkevich <iii@linux.ibm.com> | 2022-02-09 03:17:36 +0100 |
|---|---|---|
| committer |   Andrii Nakryiko <andrii@kernel.org> | 2022-02-08 21:16:14 -0800 |
| commit | 4fc49b51ab9d58e830f9df37ea775625ea966d50 (patch) | |
| tree | 6019d00a6922a9e999d7bd626f71bd09e0adf257 /tools/testing/selftests/bpf/progs/bpf_syscall_macro.c | |
| parent | Merge branch 'fix bpf_prog_pack build errors' (diff) | |
| download | linux-dev-4fc49b51ab9d58e830f9df37ea775625ea966d50.tar.xz linux-dev-4fc49b51ab9d58e830f9df37ea775625ea966d50.zip | |
selftests/bpf: Fix an endianness issue in bpf_syscall_macro test
bpf_syscall_macro reads a long argument into an int variable, which
produces a wrong value on big-endian systems. Fix by reading the
argument into an intermediate long variable first.
Fixes: 77fc0330dfe5 ("selftests/bpf: Add a test to confirm PT_REGS_PARM4_SYSCALL")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220209021745.2215452-2-iii@linux.ibm.com
Diffstat (limited to 'tools/testing/selftests/bpf/progs/bpf_syscall_macro.c')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/bpf_syscall_macro.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/tools/testing/selftests/bpf/progs/bpf_syscall_macro.c b/tools/testing/selftests/bpf/progs/bpf_syscall_macro.c index c8e60220cda8..f5c6ef2ff6d1 100644 --- a/tools/testing/selftests/bpf/progs/bpf_syscall_macro.c +++ b/tools/testing/selftests/bpf/progs/bpf_syscall_macro.c @@ -28,6 +28,7 @@ int BPF_KPROBE(handle_sys_prctl) { struct pt_regs *real_regs; pid_t pid = bpf_get_current_pid_tgid() >> 32; + unsigned long tmp; if (pid != filter_pid) return 0; @@ -35,7 +36,9 @@ int BPF_KPROBE(handle_sys_prctl) real_regs = (struct pt_regs *)PT_REGS_PARM1(ctx); /* test for PT_REGS_PARM */ - bpf_probe_read_kernel(&arg1, sizeof(arg1), &PT_REGS_PARM1_SYSCALL(real_regs)); + + bpf_probe_read_kernel(&tmp, sizeof(tmp), &PT_REGS_PARM1_SYSCALL(real_regs)); + arg1 = tmp; bpf_probe_read_kernel(&arg2, sizeof(arg2), &PT_REGS_PARM2_SYSCALL(real_regs)); bpf_probe_read_kernel(&arg3, sizeof(arg3), &PT_REGS_PARM3_SYSCALL(real_regs)); bpf_probe_read_kernel(&arg4_cx, sizeof(arg4_cx), &PT_REGS_PARM4(real_regs)); |