From: Marco Elver <elver@xxxxxxxxxx> To help catch ABI breaks at compile-time, add compile-time assertions to verify the siginfo_t layout. Link: https://lkml.kernel.org/r/20210505141101.11519-3-ebiederm@xxxxxxxxxxxx Link: https://lkml.kernel.org/r/20210429190734.624918-3-elver@xxxxxxxxxx Signed-off-by: Marco Elver <elver@xxxxxxxxxx> Signed-off-by: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> --- arch/arm64/kernel/signal.c | 37 ++++++++++++++++++++++++++++++++++++ arch/arm64/kernel/signal32.c | 37 ++++++++++++++++++++++++++++++++++++ 2 files changed, 74 insertions(+) diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c index f8192f4ae0b8..4413b6a4e32a 100644 --- a/arch/arm64/kernel/signal.c +++ b/arch/arm64/kernel/signal.c @@ -999,3 +999,40 @@ void __init minsigstksz_setup(void) round_up(sizeof(struct frame_record), 16) + 16; /* max alignment padding */ } + +/* + * Compile-time assertions for siginfo_t offsets. Check NSIG* as well, as + * changes likely come with new fields that should be added below. + */ +static_assert(NSIGILL == 11); +static_assert(NSIGFPE == 15); +static_assert(NSIGSEGV == 9); +static_assert(NSIGBUS == 5); +static_assert(NSIGTRAP == 6); +static_assert(NSIGCHLD == 6); +static_assert(NSIGSYS == 2); +static_assert(offsetof(siginfo_t, si_signo) == 0x00); +static_assert(offsetof(siginfo_t, si_errno) == 0x04); +static_assert(offsetof(siginfo_t, si_code) == 0x08); +static_assert(offsetof(siginfo_t, si_pid) == 0x10); +static_assert(offsetof(siginfo_t, si_uid) == 0x14); +static_assert(offsetof(siginfo_t, si_tid) == 0x10); +static_assert(offsetof(siginfo_t, si_overrun) == 0x14); +static_assert(offsetof(siginfo_t, si_status) == 0x18); +static_assert(offsetof(siginfo_t, si_utime) == 0x20); +static_assert(offsetof(siginfo_t, si_stime) == 0x28); +static_assert(offsetof(siginfo_t, si_value) == 0x18); +static_assert(offsetof(siginfo_t, si_int) == 0x18); +static_assert(offsetof(siginfo_t, si_ptr) == 0x18); +static_assert(offsetof(siginfo_t, si_addr) == 0x10); +static_assert(offsetof(siginfo_t, si_addr_lsb) == 0x18); +static_assert(offsetof(siginfo_t, si_lower) == 0x20); +static_assert(offsetof(siginfo_t, si_upper) == 0x28); +static_assert(offsetof(siginfo_t, si_pkey) == 0x20); +static_assert(offsetof(siginfo_t, si_perf_data) == 0x18); +static_assert(offsetof(siginfo_t, si_perf_type) == 0x20); +static_assert(offsetof(siginfo_t, si_band) == 0x10); +static_assert(offsetof(siginfo_t, si_fd) == 0x18); +static_assert(offsetof(siginfo_t, si_call_addr) == 0x10); +static_assert(offsetof(siginfo_t, si_syscall) == 0x18); +static_assert(offsetof(siginfo_t, si_arch) == 0x1c); diff --git a/arch/arm64/kernel/signal32.c b/arch/arm64/kernel/signal32.c index 2f507f565c48..ab1775216712 100644 --- a/arch/arm64/kernel/signal32.c +++ b/arch/arm64/kernel/signal32.c @@ -457,3 +457,40 @@ void compat_setup_restart_syscall(struct pt_regs *regs) { regs->regs[7] = __NR_compat_restart_syscall; } + +/* + * Compile-time assertions for siginfo_t offsets. Check NSIG* as well, as + * changes likely come with new fields that should be added below. + */ +static_assert(NSIGILL == 11); +static_assert(NSIGFPE == 15); +static_assert(NSIGSEGV == 9); +static_assert(NSIGBUS == 5); +static_assert(NSIGTRAP == 6); +static_assert(NSIGCHLD == 6); +static_assert(NSIGSYS == 2); +static_assert(offsetof(compat_siginfo_t, si_signo) == 0x00); +static_assert(offsetof(compat_siginfo_t, si_errno) == 0x04); +static_assert(offsetof(compat_siginfo_t, si_code) == 0x08); +static_assert(offsetof(compat_siginfo_t, si_pid) == 0x0c); +static_assert(offsetof(compat_siginfo_t, si_uid) == 0x10); +static_assert(offsetof(compat_siginfo_t, si_tid) == 0x0c); +static_assert(offsetof(compat_siginfo_t, si_overrun) == 0x10); +static_assert(offsetof(compat_siginfo_t, si_status) == 0x14); +static_assert(offsetof(compat_siginfo_t, si_utime) == 0x18); +static_assert(offsetof(compat_siginfo_t, si_stime) == 0x1c); +static_assert(offsetof(compat_siginfo_t, si_value) == 0x14); +static_assert(offsetof(compat_siginfo_t, si_int) == 0x14); +static_assert(offsetof(compat_siginfo_t, si_ptr) == 0x14); +static_assert(offsetof(compat_siginfo_t, si_addr) == 0x0c); +static_assert(offsetof(compat_siginfo_t, si_addr_lsb) == 0x10); +static_assert(offsetof(compat_siginfo_t, si_lower) == 0x14); +static_assert(offsetof(compat_siginfo_t, si_upper) == 0x18); +static_assert(offsetof(compat_siginfo_t, si_pkey) == 0x14); +static_assert(offsetof(compat_siginfo_t, si_perf_data) == 0x10); +static_assert(offsetof(compat_siginfo_t, si_perf_type) == 0x14); +static_assert(offsetof(compat_siginfo_t, si_band) == 0x0c); +static_assert(offsetof(compat_siginfo_t, si_fd) == 0x10); +static_assert(offsetof(compat_siginfo_t, si_call_addr) == 0x0c); +static_assert(offsetof(compat_siginfo_t, si_syscall) == 0x10); +static_assert(offsetof(compat_siginfo_t, si_arch) == 0x14); -- 2.20.1
