diff mbox series

[04/15] netfilter: bridge: stp fix reference to uninitialized data

Message ID 20180513223656.10077-5-pablo@netfilter.org
State Accepted
Delegated to: Pablo Neira
Headers show
Series [01/15] netfilter: Fix handling simultaneous open in TCP conntrack | expand

Commit Message

Pablo Neira Ayuso May 13, 2018, 10:36 p.m. UTC 
From: Stephen Hemminger <stephen@networkplumber.org>

The destination mac (destmac) is only valid if EBT_DESTMAC flag
is set. Fix by changing the order of the comparison to look for
the flag first.

Reported-by: syzbot+5c06e318fc558cc27823@syzkaller.appspotmail.com
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/bridge/netfilter/ebt_stp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/net/bridge/netfilter/ebt_stp.c b/net/bridge/netfilter/ebt_stp.c
index 47ba98db145d..46c1fe7637ea 100644
--- a/net/bridge/netfilter/ebt_stp.c
+++ b/net/bridge/netfilter/ebt_stp.c
@@ -161,8 +161,8 @@  static int ebt_stp_mt_check(const struct xt_mtchk_param *par)
 	/* Make sure the match only receives stp frames */
 	if (!par->nft_compat &&
 	    (!ether_addr_equal(e->destmac, eth_stp_addr) ||
-	     !is_broadcast_ether_addr(e->destmsk) ||
-	     !(e->bitmask & EBT_DESTMAC)))
+	     !(e->bitmask & EBT_DESTMAC) ||
+	     !is_broadcast_ether_addr(e->destmsk)))
 		return -EINVAL;
 
 	return 0;