| Message ID | mvmh713qy9m.fsf@suse.de |
|---|---|
| State | New |
| Headers | show |
| Series | socket: Use offsetof in SUN_LEN (bug 29578) | expand |
On 19/09/22 10:39, Andreas Schwab via Libc-alpha wrote: > Use offsetof instead of its traditional expansion in the definition of the > SUN_LEN macro, to avoid a warning from the undefined behaviour sanitizer. LGTM, thanks. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> > --- > socket/sys/un.h | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/socket/sys/un.h b/socket/sys/un.h > index 454eafebc9..2b11300e28 100644 > --- a/socket/sys/un.h > +++ b/socket/sys/un.h > @@ -34,10 +34,11 @@ struct sockaddr_un > > > #ifdef __USE_MISC > +# include <stddef.h> > # include <string.h> /* For prototype of `strlen'. */ > > /* Evaluate to actual length of the `sockaddr_un' structure. */ > -# define SUN_LEN(ptr) ((size_t) (((struct sockaddr_un *) 0)->sun_path) \ > +# define SUN_LEN(ptr) (offsetof (struct sockaddr_un, sun_path) \ > + strlen ((ptr)->sun_path)) > #endif >
diff --git a/socket/sys/un.h b/socket/sys/un.h index 454eafebc9..2b11300e28 100644 --- a/socket/sys/un.h +++ b/socket/sys/un.h @@ -34,10 +34,11 @@ struct sockaddr_un #ifdef __USE_MISC +# include <stddef.h> # include <string.h> /* For prototype of `strlen'. */ /* Evaluate to actual length of the `sockaddr_un' structure. */ -# define SUN_LEN(ptr) ((size_t) (((struct sockaddr_un *) 0)->sun_path) \ +# define SUN_LEN(ptr) (offsetof (struct sockaddr_un, sun_path) \ + strlen ((ptr)->sun_path)) #endif