From: Eric Dumazet <[email protected]>
Date: Mon, 26 Mar 2018 08:08:07 -0700
> skb mac header is not necessarily set at the time skb_network_protocol()
> is called. Use skb->data instead.
>
> BUG: KASAN: slab-out-of-bounds in skb_network_protocol+0x46b/0x4b0
> net/core/dev.c:2739
> Read of size 2 at addr ffff8801b3097a0b by task syz-executor5/14242
>
> CPU: 1 PID: 14242 Comm: syz-executor5 Not tainted 4.16.0-rc6+ #280
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> Call Trace:
> __dump_stack lib/dump_stack.c:17 [inline]
> dump_stack+0x194/0x24d lib/dump_stack.c:53
> print_address_description+0x73/0x250 mm/kasan/report.c:256
> kasan_report_error mm/kasan/report.c:354 [inline]
> kasan_report+0x23c/0x360 mm/kasan/report.c:412
> __asan_report_load_n_noabort+0xf/0x20 mm/kasan/report.c:443
> skb_network_protocol+0x46b/0x4b0 net/core/dev.c:2739
> harmonize_features net/core/dev.c:2924 [inline]
> netif_skb_features+0x509/0x9b0 net/core/dev.c:3011
> validate_xmit_skb+0x81/0xb00 net/core/dev.c:3084
> validate_xmit_skb_list+0xbf/0x120 net/core/dev.c:3142
> packet_direct_xmit+0x117/0x790 net/packet/af_packet.c:256
> packet_snd net/packet/af_packet.c:2944 [inline]
> packet_sendmsg+0x3aed/0x60b0 net/packet/af_packet.c:2969
> sock_sendmsg_nosec net/socket.c:629 [inline]
> sock_sendmsg+0xca/0x110 net/socket.c:639
> ___sys_sendmsg+0x767/0x8b0 net/socket.c:2047
> __sys_sendmsg+0xe5/0x210 net/socket.c:2081
>
> Fixes: 19acc327258a ("gso: Handle Trans-Ether-Bridging protocol in
> skb_network_protocol()")
> Signed-off-by: Eric Dumazet <[email protected]>
> Cc: Pravin B Shelar <[email protected]>
> Reported-by: Reported-by: syzbot <[email protected]>
Applied and queued up for -stable, thanks Eric.
