Message ID | 1508260064.31614.108.camel@edumazet-glaptop3.roam.corp.google.com |
---|---|
State | Accepted, archived |
Delegated to: | David Miller |
Headers | show |
Series | [net-next] tun: relax check on eth_get_headlen() return value | expand |
From: Eric Dumazet <eric.dumazet@gmail.com> Date: Tue, 17 Oct 2017 10:07:44 -0700 > From: Eric Dumazet <edumazet@google.com> > > syzkaller hit the WARN() in tun_get_user(), providing skb > with payload in fragments only, and nothing in skb->head > > GRO layer is fine with this, so relax the check. > > Fixes: 90e33d459407 ("tun: enable napi_gro_frags() for TUN/TAP driver") > Signed-off-by: Eric Dumazet <edumazet@google.com> Applied.
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 57e4c31fa84adc4d9af6ab69a87feac23a8b034e..c64ec19af9b73744270f5cdb922d0f0c1c8f4443 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1737,7 +1737,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, /* Exercise flow dissector code path. */ u32 headlen = eth_get_headlen(skb->data, skb_headlen(skb)); - if (headlen > skb_headlen(skb) || headlen < ETH_HLEN) { + if (unlikely(headlen > skb_headlen(skb))) { this_cpu_inc(tun->pcpu_stats->rx_dropped); napi_free_frags(&tfile->napi); mutex_unlock(&tfile->napi_mutex);