linux/net/ipv6
Alexander Duyck ed7cbbce54 udp: Resolve NULL pointer dereference over flow-based vxlan device
While testing an OpenStack configuration using VXLANs I saw the following
call trace:

 RIP: 0010:[<ffffffff815fad49>] udp4_lib_lookup_skb+0x49/0x80
 RSP: 0018:ffff88103867bc50  EFLAGS: 00010286
 RAX: ffff88103269bf00 RBX: ffff88103269bf00 RCX: 00000000ffffffff
 RDX: 0000000000004300 RSI: 0000000000000000 RDI: ffff880f2932e780
 RBP: ffff88103867bc60 R08: 0000000000000000 R09: 000000009001a8c0
 R10: 0000000000004400 R11: ffffffff81333a58 R12: ffff880f2932e794
 R13: 0000000000000014 R14: 0000000000000014 R15: ffffe8efbfd89ca0
 FS:  0000000000000000(0000) GS:ffff88103fd80000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000488 CR3: 0000000001c06000 CR4: 00000000001426e0
 Stack:
  ffffffff81576515 ffffffff815733c0 ffff88103867bc98 ffffffff815fcc17
  ffff88103269bf00 ffffe8efbfd89ca0 0000000000000014 0000000000000080
  ffffe8efbfd89ca0 ffff88103867bcc8 ffffffff815fcf8b ffff880f2932e794
 Call Trace:
  [<ffffffff81576515>] ? skb_checksum+0x35/0x50
  [<ffffffff815733c0>] ? skb_push+0x40/0x40
  [<ffffffff815fcc17>] udp_gro_receive+0x57/0x130
  [<ffffffff815fcf8b>] udp4_gro_receive+0x10b/0x2c0
  [<ffffffff81605863>] inet_gro_receive+0x1d3/0x270
  [<ffffffff81589e59>] dev_gro_receive+0x269/0x3b0
  [<ffffffff8158a1b8>] napi_gro_receive+0x38/0x120
  [<ffffffffa0871297>] gro_cell_poll+0x57/0x80 [vxlan]
  [<ffffffff815899d0>] net_rx_action+0x160/0x380
  [<ffffffff816965c7>] __do_softirq+0xd7/0x2c5
  [<ffffffff8107d969>] run_ksoftirqd+0x29/0x50
  [<ffffffff8109a50f>] smpboot_thread_fn+0x10f/0x160
  [<ffffffff8109a400>] ? sort_range+0x30/0x30
  [<ffffffff81096da8>] kthread+0xd8/0xf0
  [<ffffffff81693c82>] ret_from_fork+0x22/0x40
  [<ffffffff81096cd0>] ? kthread_park+0x60/0x60

The following trace is seen when receiving a DHCP request over a flow-based
VXLAN tunnel.  I believe this is caused by the metadata dst having a NULL
dev value and as a result dev_net(dev) is causing a NULL pointer dereference.

To resolve this I am replacing the check for skb_dst(skb)->dev with just
skb->dev.  This makes sense as the callers of this function are usually in
the receive path and as such skb->dev should always be populated.  In
addition other functions in the area where these are called are already
using dev_net(skb->dev) to determine the namespace the UDP packet belongs
in.

Fixes: 63058308cd ("udp: Add udp6_lib_lookup_skb and udp4_lib_lookup_skb")
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-13 01:56:14 -04:00
..
ila ila: ipv6/ila: fix nlsize calculation for lwtunnel 2016-05-10 16:00:25 -04:00
netfilter netfilter: x_tables: get rid of old and inconsistent debugging 2016-05-05 16:39:51 +02:00
Kconfig gre6: add Kconfig dependency for NET_IPGRE_DEMUX 2016-05-04 14:12:36 -04:00
Makefile udp: Add GRO functions to UDP socket 2016-04-07 16:53:29 -04:00
addrconf.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-04-27 15:43:10 -04:00
addrconf_core.c ipv6: change ipv6_stub_impl.ipv6_dst_lookup to take net argument 2015-07-31 15:21:30 -07:00
addrlabel.c ipv6/addrlabel: fix ip6addrlbl_get() 2015-12-22 15:57:54 -05:00
af_inet6.c udp: Add GRO functions to UDP socket 2016-04-07 16:53:29 -04:00
ah6.c ah6: fix error return code 2015-08-25 13:37:31 -07:00
anycast.c ipv6: coding style: comparison for equality with NULL 2015-03-31 13:51:54 -04:00
datagram.c ipv6: add new struct ipcm6_cookie 2016-05-03 16:08:14 -04:00
esp6.c esp6: Switch to new AEAD interface 2015-05-28 11:23:20 +08:00
exthdrs.c ipv6: rename IP6_INC_STATS_BH() 2016-04-27 22:48:24 -04:00
exthdrs_core.c ipv6: re-enable fragment header matching in ipv6_find_hdr 2016-03-03 16:35:20 -05:00
exthdrs_offload.c ipv6: fix exthdrs offload registration in out_rt path 2015-09-02 15:31:00 -07:00
fib6_rules.c ipv6: fix the incorrect return value of throw route 2015-10-23 02:38:18 -07:00
icmp.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-05-09 15:59:24 -04:00
inet6_connection_sock.c soreuseport: fast reuseport TCP socket selection 2016-02-11 03:54:15 -05:00
inet6_hashtables.c net: rename NET_{ADD|INC}_STATS_BH() 2016-04-27 22:48:24 -04:00
ip6_checksum.c ipv6: Pass proto to csum_ipv6_magic as __u8 instead of unsigned short 2016-03-13 23:55:13 -04:00
ip6_fib.c net: vrf: Create FIB tables on link create 2016-05-06 15:51:47 -04:00
ip6_flowlabel.c ipv6: add new struct ipcm6_cookie 2016-05-03 16:08:14 -04:00
ip6_gre.c gre: Fix wrong tpi->proto in WCCP 2016-05-12 16:53:58 -04:00
ip6_icmp.c ipv6: White-space cleansing : Line Layouts 2014-08-24 22:37:52 -07:00
ip6_input.c net: l3mdev: Add hook in ip and ipv6 2016-05-11 19:31:40 -04:00
ip6_offload.c GSO: Support partial segmentation offload 2016-04-14 16:23:41 -04:00
ip6_offload.h udp: Add GRO functions to UDP socket 2016-04-07 16:53:29 -04:00
ip6_output.c ipv6: add new struct ipcm6_cookie 2016-05-03 16:08:14 -04:00
ip6_tunnel.c ipv6: fix 4in6 tunnel receive path 2016-05-11 19:23:55 -04:00
ip6_udp_tunnel.c ip_tunnel: add support for setting flow label via collect metadata 2016-03-11 15:14:26 -05:00
ip6_vti.c net: replace dst_cache ip6_tunnel implementation with the generic one 2016-02-16 20:21:48 -05:00
ip6mr.c ipv6: rename IP6_INC_STATS_BH() 2016-04-27 22:48:24 -04:00
ipcomp6.c ipv6: White-space cleansing : Structure layouts 2014-08-24 22:37:52 -07:00
ipv6_sockglue.c ipv6: add new struct ipcm6_cookie 2016-05-03 16:08:14 -04:00
mcast.c mld, igmp: Fix reserved tailroom calculation 2016-03-03 15:41:07 -05:00
mcast_snoop.c net: fix wrong skb_get() usage / crash in IGMP/MLD parsing code 2015-08-13 17:08:39 -07:00
mip6.c ipv6: use ktime_t for internal timestamps 2015-10-05 03:16:47 -07:00
ndisc.c ipv6: add option to drop unsolicited neighbor advertisements 2016-02-11 04:27:36 -05:00
netfilter.c ipv6: Pass struct net into ip6_route_me_harder 2015-09-29 20:21:32 +02:00
output_core.c ipv4, ipv6: Pass net into ip_local_out and ip6_local_out 2015-10-08 04:27:02 -07:00
ping.c ipv6: add new struct ipcm6_cookie 2016-05-03 16:08:14 -04:00
proc.c udp: Increment UDP_MIB_IGNOREDMULTI for arriving unmatched multicasts 2014-11-07 15:45:50 -05:00
protocol.c net: Export inet_offloads and inet6_offloads 2014-09-19 17:15:31 -04:00
raw.c ipv6: add new struct ipcm6_cookie 2016-05-03 16:08:14 -04:00
reassembly.c ipv6: rename IP6_INC_STATS_BH() 2016-04-27 22:48:24 -04:00
route.c net: l3mdev: Move get_saddr and rt6_dst 2016-05-09 22:33:52 -04:00
sit.c ip_tunnel_core: iptunnel_handle_offloads returns int and doesn't free skb 2016-04-16 19:09:13 -04:00
syncookies.c net: rename NET_{ADD|INC}_STATS_BH() 2016-04-27 22:48:24 -04:00
sysctl_net_ipv6.c ipv6: Implement different admin modes for automatic flow labels 2015-07-31 17:07:11 -07:00
tcp_ipv6.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-05-09 15:59:24 -04:00
tcpv6_offload.c tcp: cleanup static functions 2015-02-28 16:56:51 -05:00
tunnel6.c ipv6: fix tunnel error handling 2015-11-03 10:52:13 -05:00
udp.c udp: Resolve NULL pointer dereference over flow-based vxlan device 2016-05-13 01:56:14 -04:00
udp_impl.h net: Remove iocb argument from sendmsg and recvmsg 2015-03-02 13:06:31 -05:00
udp_offload.c udp: Add GRO functions to UDP socket 2016-04-07 16:53:29 -04:00
udplite.c net: Eliminate no_check from protosw 2014-05-23 16:28:53 -04:00
xfrm6_input.c netfilter: Pass struct net into the netfilter hooks 2015-09-17 17:18:37 -07:00
xfrm6_mode_beet.c xfrm: simplify xfrm_address_t use 2015-03-31 13:58:35 -04:00
xfrm6_mode_ro.c
xfrm6_mode_transport.c
xfrm6_mode_tunnel.c ipv6: update skb->csum when CE mark is propagated 2016-01-15 15:07:23 -05:00
xfrm6_output.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-10-24 06:54:12 -07:00
xfrm6_policy.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec 2015-12-22 16:26:31 -05:00
xfrm6_protocol.c xfrm6: Properly handle unsupported protocols 2014-05-06 07:08:38 +02:00
xfrm6_state.c ipv6: White-space cleansing : Line Layouts 2014-08-24 22:37:52 -07:00
xfrm6_tunnel.c ipv6: White-space cleansing : gaps between function and symbol export 2014-08-24 22:37:52 -07:00