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| author | Eric W. Biederman <ebiederm@xmission.com> | 2021-05-04 11:25:22 -0500 |
|---|---|---|
| committer | Eric W. Biederman <ebiederm@xmission.com> | 2021-07-23 13:15:31 -0500 |
| commit | 50ae81305c7a3ee802f0a1988503ce913c79cd6e (patch) | |
| tree | 8564c815a010b129d6af244f1570ad55f763757f /arch/sparc | |
| parent | c7fff9288dce1ee5fa9de8d656e09cc8e0e3281b (diff) | |
| download | linux-50ae81305c7a3ee802f0a1988503ce913c79cd6e.tar.gz | |
signal: Verify the alignment and size of siginfo_t
Update the static assertions about siginfo_t to also describe it's alignment and size. While investigating if it was possible to add a 64bit field into siginfo_t[1] it became apparent that the alignment of siginfo_t is as much a part of the ABI as the size of the structure. If the alignment changes siginfo_t when embedded in another structure can move to a different offset. Which is not acceptable from an ABI structure. So document that fact and add static assertions to notify developers if they change change the alignment by accident. [1] https://lkml.kernel.org/r/YJEZdhe6JGFNYlum@elver.google.com Acked-by: Marco Elver <elver@google.com> v1: https://lkml.kernel.org/r/20210505141101.11519-4-ebiederm@xmission.co Link: https://lkml.kernel.org/r/875yxaxmyl.fsf_-_@disp2133 Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Diffstat (limited to 'arch/sparc')
| -rw-r--r-- | arch/sparc/kernel/signal32.c | 2 | ||||
| -rw-r--r-- | arch/sparc/kernel/signal_64.c | 2 |
2 files changed, 4 insertions, 0 deletions
diff --git a/arch/sparc/kernel/signal32.c b/arch/sparc/kernel/signal32.c index 65fd26ae9d25..4276b9e003ca 100644 --- a/arch/sparc/kernel/signal32.c +++ b/arch/sparc/kernel/signal32.c @@ -757,6 +757,8 @@ static_assert(NSIGBUS == 5); static_assert(NSIGTRAP == 6); static_assert(NSIGCHLD == 6); static_assert(NSIGSYS == 2); +static_assert(sizeof(compat_siginfo_t) == 128); +static_assert(__alignof__(compat_siginfo_t) == 4); 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); diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c index a58e0cc45d24..cea23cf95600 100644 --- a/arch/sparc/kernel/signal_64.c +++ b/arch/sparc/kernel/signal_64.c @@ -567,6 +567,8 @@ static_assert(NSIGBUS == 5); static_assert(NSIGTRAP == 6); static_assert(NSIGCHLD == 6); static_assert(NSIGSYS == 2); +static_assert(sizeof(siginfo_t) == 128); +static_assert(__alignof__(siginfo_t) == 8); static_assert(offsetof(siginfo_t, si_signo) == 0x00); static_assert(offsetof(siginfo_t, si_errno) == 0x04); static_assert(offsetof(siginfo_t, si_code) == 0x08); |