linux/net
Eric Dumazet ff907a11a0 net: skb_segment() should not return NULL
syzbot caught a NULL deref [1], caused by skb_segment()

skb_segment() has many "goto err;" that assume the @err variable
contains -ENOMEM.

A successful call to __skb_linearize() should not clear @err,
otherwise a subsequent memory allocation error could return NULL.

While we are at it, we might use -EINVAL instead of -ENOMEM when
MAX_SKB_FRAGS limit is reached.

[1]
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
CPU: 0 PID: 13285 Comm: syz-executor3 Not tainted 4.18.0-rc4+ #146
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:tcp_gso_segment+0x3dc/0x1780 net/ipv4/tcp_offload.c:106
Code: f0 ff ff 0f 87 1c fd ff ff e8 00 88 0b fb 48 8b 75 d0 48 b9 00 00 00 00 00 fc ff df 48 8d be 90 00 00 00 48 89 f8 48 c1 e8 03 <0f> b6 14 08 48 8d 86 94 00 00 00 48 89 c6 83 e0 07 48 c1 ee 03 0f
RSP: 0018:ffff88019b7fd060 EFLAGS: 00010206
RAX: 0000000000000012 RBX: 0000000000000020 RCX: dffffc0000000000
RDX: 0000000000040000 RSI: 0000000000000000 RDI: 0000000000000090
RBP: ffff88019b7fd0f0 R08: ffff88019510e0c0 R09: ffffed003b5c46d6
R10: ffffed003b5c46d6 R11: ffff8801dae236b3 R12: 0000000000000001
R13: ffff8801d6c581f4 R14: 0000000000000000 R15: ffff8801d6c58128
FS:  00007fcae64d6700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004e8664 CR3: 00000001b669b000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tcp4_gso_segment+0x1c3/0x440 net/ipv4/tcp_offload.c:54
 inet_gso_segment+0x64e/0x12d0 net/ipv4/af_inet.c:1342
 inet_gso_segment+0x64e/0x12d0 net/ipv4/af_inet.c:1342
 skb_mac_gso_segment+0x3b5/0x740 net/core/dev.c:2792
 __skb_gso_segment+0x3c3/0x880 net/core/dev.c:2865
 skb_gso_segment include/linux/netdevice.h:4099 [inline]
 validate_xmit_skb+0x640/0xf30 net/core/dev.c:3104
 __dev_queue_xmit+0xc14/0x3910 net/core/dev.c:3561
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3602
 neigh_hh_output include/net/neighbour.h:473 [inline]
 neigh_output include/net/neighbour.h:481 [inline]
 ip_finish_output2+0x1063/0x1860 net/ipv4/ip_output.c:229
 ip_finish_output+0x841/0xfa0 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:276 [inline]
 ip_output+0x223/0x880 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:444 [inline]
 ip_local_out+0xc5/0x1b0 net/ipv4/ip_output.c:124
 iptunnel_xmit+0x567/0x850 net/ipv4/ip_tunnel_core.c:91
 ip_tunnel_xmit+0x1598/0x3af1 net/ipv4/ip_tunnel.c:778
 ipip_tunnel_xmit+0x264/0x2c0 net/ipv4/ipip.c:308
 __netdev_start_xmit include/linux/netdevice.h:4148 [inline]
 netdev_start_xmit include/linux/netdevice.h:4157 [inline]
 xmit_one net/core/dev.c:3034 [inline]
 dev_hard_start_xmit+0x26c/0xc30 net/core/dev.c:3050
 __dev_queue_xmit+0x29ef/0x3910 net/core/dev.c:3569
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3602
 neigh_direct_output+0x15/0x20 net/core/neighbour.c:1403
 neigh_output include/net/neighbour.h:483 [inline]
 ip_finish_output2+0xa67/0x1860 net/ipv4/ip_output.c:229
 ip_finish_output+0x841/0xfa0 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:276 [inline]
 ip_output+0x223/0x880 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:444 [inline]
 ip_local_out+0xc5/0x1b0 net/ipv4/ip_output.c:124
 ip_queue_xmit+0x9df/0x1f80 net/ipv4/ip_output.c:504
 tcp_transmit_skb+0x1bf9/0x3f10 net/ipv4/tcp_output.c:1168
 tcp_write_xmit+0x1641/0x5c20 net/ipv4/tcp_output.c:2363
 __tcp_push_pending_frames+0xb2/0x290 net/ipv4/tcp_output.c:2536
 tcp_push+0x638/0x8c0 net/ipv4/tcp.c:735
 tcp_sendmsg_locked+0x2ec5/0x3f00 net/ipv4/tcp.c:1410
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1447
 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:641 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:651
 __sys_sendto+0x3d7/0x670 net/socket.c:1797
 __do_sys_sendto net/socket.c:1809 [inline]
 __se_sys_sendto net/socket.c:1805 [inline]
 __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1805
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x455ab9
Code: 1d ba fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb b9 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fcae64d5c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fcae64d66d4 RCX: 0000000000455ab9
RDX: 0000000000000001 RSI: 0000000020000200 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000014
R13: 00000000004c1145 R14: 00000000004d1818 R15: 0000000000000006
Modules linked in:
Dumping ftrace buffer:
   (ftrace buffer empty)

Fixes: ddff00d420 ("net: Move skb_has_shared_frag check out of GRE code and into segmentation")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 19:34:18 -07:00
..
6lowpan
9p net/9p/client.c: put refcount of trans_mod in error case in parse_opts() 2018-07-14 11:11:09 -07:00
802
8021q net: fix use-after-free in GRO with ESP 2018-07-02 20:34:04 +09:00
appletalk Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
atm Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
ax25 Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
batman-adv batman-adv: Fix multicast TT issues with bogus ROAM flags 2018-06-23 10:29:33 +02:00
bluetooth Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
bpf bpf: fix panic due to oob in bpf_prog_test_run_skb 2018-07-11 16:10:57 -07:00
bpfilter bpfilter: include bpfilter_umh in assembly instead of using objcopy 2018-06-28 21:39:16 +09:00
bridge Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-06-16 07:39:34 +09:00
caif net: caif: Add a missing rcu_read_unlock() in caif_flow_cb 2018-07-21 16:14:39 -07:00
can Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
ceph The main piece is a set of libceph changes that revamps how OSD 2018-06-15 07:24:58 +09:00
core net: skb_segment() should not return NULL 2018-07-21 19:34:18 -07:00
dcb treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
dccp Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
decnet Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
dns_resolver KEYS: DNS: fix parsing multiple options 2018-07-16 11:22:14 -07:00
dsa net: dsa: add error handling for pskb_trim_rcsum 2018-06-11 14:19:38 -07:00
ethernet net: core: rework basic flow dissection helper 2018-05-08 00:02:36 -04:00
hsr
ieee802154 ieee802154: 6lowpan: set IFLA_LINK 2018-07-05 11:13:17 +02:00
ife net: sched: ife: check on metadata length 2018-04-22 21:12:00 -04:00
ipv4 tcp: do not delay ACK in DCTCP upon CE status change 2018-07-20 14:32:23 -07:00
ipv6 net/ipv6: Fix linklocal to global address with VRF 2018-07-21 19:31:46 -07:00
iucv Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
kcm Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
key Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
l2tp Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
l3mdev
lapb
llc Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
mac80211 mac80211: disable BHs/preemption in ieee80211_tx_control_port() 2018-06-29 09:39:08 +02:00
mac802154 net/mac802154: disambiguate mac80215 vs mac802154 trace events 2018-03-28 22:55:18 +02:00
mpls net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
ncsi net/ncsi: Use netdev_dbg for debug messages 2018-06-20 07:26:58 +09:00
netfilter netfilter: nf_conntrack: Fix possible possible crash on module loading. 2018-07-09 18:04:11 +02:00
netlabel audit: use inline function to get audit context 2018-05-14 17:24:18 -04:00
netlink Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
netrom Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
nfc net/nfc: Avoid stalls when nfc_alloc_send_skb() returned NULL. 2018-07-18 10:51:45 -07:00
nsh nsh: set mac len based on inner packet 2018-07-12 16:55:29 -07:00
openvswitch treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
packet packet: reset network header if packet shorter than ll reserved space 2018-07-12 16:55:59 -07:00
phonet Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
psample
qrtr net: qrtr: Reset the node and port ID of broadcast messages 2018-07-05 20:20:03 +09:00
rds rds: clean up loopback rds_connections on netns deletion 2018-06-27 10:11:03 +09:00
rfkill rfkill: Create rfkill-none LED trigger 2018-05-23 11:26:45 +02:00
rose Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
rxrpc Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
sched net: sched: Using NULL instead of plain integer 2018-07-18 13:44:07 -07:00
sctp sctp: fix the issue that pathmtu may be set lower than MINSEGMENT 2018-07-04 21:36:34 +09:00
smc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-07-18 19:32:54 -07:00
strparser strparser: Remove early eaten to fix full tcp receive buffer stall 2018-06-28 21:37:26 +09:00
sunrpc NFS client bugfixes for Linux 4.18 2018-06-22 06:21:34 +09:00
switchdev
tipc tipc: make function tipc_net_finalize() thread safe 2018-07-07 19:49:02 +09:00
tls tls: check RCV_SHUTDOWN in tls_wait_data 2018-07-20 14:38:14 -07:00
unix Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
vmw_vsock Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
wimax
wireless nl80211: check nla_parse_nested() return values 2018-06-29 09:44:51 +02:00
x25 Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
xdp xsk: do not return EMSGSIZE in copy mode for packets larger than MTU 2018-07-13 15:34:31 +02:00
xfrm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
compat.c net: support compat 64-bit time in {s,g}etsockopt 2018-04-27 19:46:06 -04:00
Kconfig net: Introduce generic failover module 2018-05-28 22:59:54 -04:00
Makefile bpfilter: check compiler capability in Kconfig 2018-06-28 13:36:39 +09:00
socket.c net: handle NULL ->poll gracefully 2018-06-29 06:51:51 -07:00
sysctl_net.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00