wext: handle NULL extra data in iwe_stream_add_point better

commit 93be2b74279c15c2844684b1a027fdc71dd5d9bf upstream.

gcc-7 complains that wl3501_cs passes NULL into a function that
then uses the argument as the input for memcpy:

drivers/net/wireless/wl3501_cs.c: In function 'wl3501_get_scan':
include/net/iw_handler.h:559:3: error: argument 2 null where non-null expected [-Werror=nonnull]
   memcpy(stream + point_len, extra, iwe->u.data.length);

This works fine here because iwe->u.data.length is guaranteed to be 0
and the memcpy doesn't actually have an effect.

Making the length check explicit avoids the warning and should have
no other effect here.

Also check the pointer itself, since otherwise we get warnings
elsewhere in the code.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
This commit is contained in:
Arnd Bergmann 2017-01-11 15:35:25 +01:00 committed by syphyr
parent 8a007513db
commit 94e419a6ae
1 changed files with 2 additions and 1 deletions

View File

@ -551,7 +551,8 @@ iwe_stream_add_point(struct iw_request_info *info, char *stream, char *ends,
memcpy(stream + lcp_len,
((char *) &iwe->u) + IW_EV_POINT_OFF,
IW_EV_POINT_PK_LEN - IW_EV_LCP_PK_LEN);
memcpy(stream + point_len, extra, iwe->u.data.length);
if (iwe->u.data.length && extra)
memcpy(stream + point_len, extra, iwe->u.data.length);
stream += event_len;
}
return stream;