| Message ID | 20180427181609.3103-1-sthemmin@microsoft.com |
|---|---|
| State | Accepted |
| Delegated to: | Pablo Neira |
| Headers | show |
| Series | [net] bridge: netfilter stp fix reference to uninitialized data | expand |
On Fri, Apr 27, 2018 at 11:16:09AM -0700, Stephen Hemminger wrote: > 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. Applied, thanks Stephen. -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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;
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> --- Note: no fixes since this bug goes back to pre-git days. Should go to stable as well. net/bridge/netfilter/ebt_stp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)