I started getting warnings for this one file, though I can't see what changed
since it was originally introduced in commit fec7b66905 ("samples: add an
example of seccomp user trap").
samples/seccomp/user-trap.c: In function 'send_fd':
samples/seccomp/user-trap.c:50:11: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
50 | *((int *)CMSG_DATA(cmsg)) = fd;
| ~^~~~~~~~~~~~~~~~~~~~~~~
samples/seccomp/user-trap.c: In function 'recv_fd':
samples/seccomp/user-trap.c:83:18: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
83 | return *((int *)CMSG_DATA(cmsg));
| ~^~~~~~~~~~~~~~~~~~~~~~~
Using a temporary pointer variable avoids the warning.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20240212111737.917428-1-arnd@kernel.org
Acked-by: Tycho Andersen <tandersen@netflix.com>
Signed-off-by: Kees Cook <keescook@chromium.org>