[NET]: Do not memcmp() over pad bytes of struct flowi.
They are not necessarily initialized to zero by the compiler,
for example when using run-time initializers of automatic
on-stack variables.
Noticed by Eric Dumazet and Patrick McHardy.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index c41ddba..925ee4d 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -566,9 +566,15 @@
static inline int compare_keys(struct flowi *fl1, struct flowi *fl2)
{
- return memcmp(&fl1->nl_u.ip4_u, &fl2->nl_u.ip4_u, sizeof(fl1->nl_u.ip4_u)) == 0 &&
- fl1->oif == fl2->oif &&
- fl1->iif == fl2->iif;
+ return ((fl1->nl_u.ip4_u.daddr ^ fl2->nl_u.ip4_u.daddr) |
+ (fl1->nl_u.ip4_u.saddr ^ fl2->nl_u.ip4_u.saddr) |
+#ifdef CONFIG_IP_ROUTE_FWMARK
+ (fl1->nl_u.ip4_u.fwmark ^ fl2->nl_u.ip4_u.fwmark) |
+#endif
+ (*(u16 *)&fl1->nl_u.ip4_u.tos ^
+ *(u16 *)&fl2->nl_u.ip4_u.tos) |
+ (fl1->oif ^ fl2->oif) |
+ (fl1->iif ^ fl2->iif)) == 0;
}
#ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED