This is another false positive in bad cast detection: net/unix/af_unix.c: In function ‘unix_skb_scm_eq’: net/unix/af_unix.c:1621:31: note: found mismatched rhs struct pointer types: ‘struct unix_skb_parms’ and ‘char’
const struct unix_skb_parms *u = &UNIXCB(skb); ^ UNIXCB is: #define UNIXCB(skb) (*(struct unix_skb_parms *)&((skb)->cb)) And ->cb is: char cb[48] __aligned(8); This is a rather crazy cast, but appears to be safe in the face of randomization, so whitelist it in the plugin. Cc: Hannes Frederic Sowa <han...@stressinduktion.org> Cc: Signed-off-by: David S. Miller <da...@davemloft.net> Signed-off-by: Kees Cook <keesc...@chromium.org> --- scripts/gcc-plugins/randomize_layout_plugin.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/scripts/gcc-plugins/randomize_layout_plugin.c b/scripts/gcc-plugins/randomize_layout_plugin.c index e126ac7874af..bf110915a5aa 100644 --- a/scripts/gcc-plugins/randomize_layout_plugin.c +++ b/scripts/gcc-plugins/randomize_layout_plugin.c @@ -43,6 +43,8 @@ struct whitelist_entry { }; static const struct whitelist_entry whitelist[] = { + /* unix_skb_parms via UNIXCB() buffer */ + { "net/unix/af_unix.c", "unix_skb_parms", "char" }, /* walk struct security_hook_heads as an array of struct list_head */ { "security/security.c", "list_head", "security_hook_heads" }, { } -- 2.7.4