syzbot


BUG: unable to handle kernel NULL pointer dereference in ip_output

Status: closed as invalid on 2018/06/10 06:26
Subsystems: mm
[Documentation on labels]
First crash: 2635d, last: 2635d

Sample crash report:
 __should_failslab+0x124/0x180 mm/failslab.c:32
 should_failslab+0x9/0x14 mm/slab_common.c:1522
 slab_pre_alloc_hook mm/slab.h:423 [inline]
 slab_alloc_node mm/slab.c:3299 [inline]
 kmem_cache_alloc_node+0x56/0x780 mm/slab.c:3642
 __alloc_skb+0x111/0x780 net/core/skbuff.c:193
BUG: unable to handle kernel NULL pointer dereference
 at 0000000000000000
PGD 1d7b10067 
P4D 1d7b10067 
PUD 1b596b067 
PMD 0 
 alloc_skb include/linux/skbuff.h:987 [inline]
 ip_do_fragment+0xb66/0x2ac0 net/ipv4/ip_output.c:739
Oops: 0010 [#1] SMP KASAN
CPU: 1 PID: 23163 Comm: syz-executor4 Not tainted 4.17.0+ #83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:          (null)
Code: 
Bad RIP value.
RSP: 0018:ffff88018036f3a0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8801d90ce800 RCX: 1ffffffff10ea785
RDX: ffff88018036fc00 RSI: ffff8801c98ef480 RDI: ffff8801cad68800
RBP: ffff88018036f510 R08: ffff8801be3bad38 R09: 0000000000000006
R10: ffff8801be3ba500 R11: 0000000000000000 R12: 1ffff1003006de79
 ip_fragment.constprop.49+0x179/0x240 net/ipv4/ip_output.c:546
R13: ffff88018036fc00 R14: ffff8801d90ce812 R15: ffff8801d90cec58
 ip_finish_output+0x6cb/0xf80 net/ipv4/ip_output.c:315
FS:  00007ffa2e371700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001d7b11000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 NF_HOOK_COND include/linux/netfilter.h:276 [inline]
 ip_output+0x21b/0x850 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+0x9d7/0x1f70 net/ipv4/ip_output.c:504
 sock_poll+0x1d1/0x710 net/socket.c:1156
 tcp_transmit_skb+0x1bea/0x3ec0 net/ipv4/tcp_output.c:1168
 vfs_poll+0x77/0x2a0 fs/select.c:40
 ep_item_poll.isra.15+0x2c1/0x390 fs/eventpoll.c:887
 ep_insert+0x6b8/0x1c00 fs/eventpoll.c:1459
 tcp_write_xmit+0x1626/0x5c00 net/ipv4/tcp_output.c:2363
 __tcp_push_pending_frames+0xb2/0x290 net/ipv4/tcp_output.c:2536
 tcp_sendmsg_locked+0x2c6b/0x3ee0 net/ipv4/tcp.c:1377
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1436
 inet_sendmsg+0x19f/0x690 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:633 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:643
 __sys_sendto+0x3d7/0x670 net/socket.c:1821
 __do_sys_sendto net/socket.c:1833 [inline]
 __se_sys_sendto net/socket.c:1829 [inline]
 __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1829
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4559f9
Code: 
1d 
ba 
fb 
ff 
c3 
66 
2e 
0f 
1f 
84 
00 
00 
00 
 __do_sys_epoll_ctl fs/eventpoll.c:2113 [inline]
 __se_sys_epoll_ctl fs/eventpoll.c:1999 [inline]
 __x64_sys_epoll_ctl+0xef1/0x10f0 fs/eventpoll.c:1999
00 
00 
66 
90 
48 
89 
f8 
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
48 89 
f7 48 
89 
d6 
48 
89 
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
ca 
RIP: 0033:0x4559f9
4d 
Code: 
89 c2 
1d 
4d 
ba 
89 c8 
fb 
4c 
ff 
8b 
c3 
4c 
66 
24 
2e 
08 
0f 
0f 
1f 
05 
84 
<48> 
00 
3d 
00 
01 
00 00 
f0 ff 
00 
ff 
66 
0f 
90 
83 
48 
eb 
89 
b9 
f8 
fb 
48 89 
ff 
f7 
c3 
48 
66 
89 
2e 
d6 
0f 
48 
1f 
89 
84 
ca 
00 
4d 
00 
89 
00 
c2 
00 
4d 
89 
RSP: 002b:00007f3e73ae3c68 EFLAGS: 00000246
c8 
 ORIG_RAX: 000000000000002c
4c 8b 
RAX: ffffffffffffffda RBX: 00007f3e73ae46d4 RCX: 00000000004559f9
4c 
RDX: fffffffffffffe4e RSI: 0000000020000000 RDI: 0000000000000014
24 08 
RBP: 000000000072bea0 R08: 00000000200000c0 R09: 0000000000000006
0f 
R10: 00000000000000c0 R11: 0000000000000246 R12: 0000000000000015
05 
R13: 00000000004c0d2f R14: 00000000004d0790 R15: 000000000000002a
<48> 3d 01 f0 ff ff 0f 83 eb b9 fb ff c3 66 2e 0f 1f 84 00 00 00 00 
RSP: 002b:00007ffa2e370c68 EFLAGS: 00000246 ORIG_RAX: 00000000000000e9
RAX: ffffffffffffffda RBX: 00007ffa2e3716d4 RCX: 00000000004559f9
RDX: 0000000000000014 RSI: 0000000000000001 RDI: 0000000000000015
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004bb8e9 R14: 00000000004c83f0 R15: 0000000000000000
Modules linked in:
Dumping ftrace buffer:
   (ftrace buffer empty)
CR2: 0000000000000000
---[ end trace 52ad44f27d97cbd9 ]---
RIP: 0010:          (null)
Code: Bad RIP value.
RSP: 0018:ffff88018036f3a0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8801d90ce800 RCX: 1ffffffff10ea785
RDX: ffff88018036fc00 RSI: ffff8801c98ef480 RDI: ffff8801cad68800
RBP: ffff88018036f510 R08: ffff8801be3bad38 R09: 0000000000000006
R10: ffff8801be3ba500 R11: 0000000000000000 R12: 1ffff1003006de79
R13: ffff88018036fc00 R14: ffff8801d90ce812 R15: ffff8801d90cec58
FS:  00007ffa2e371700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000001d7b11000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/06/10 04:37 net-next-old 3a979e8c07e3 866118af .config console log report ci-upstream-net-kasan-gce
* Struck through repros no longer work on HEAD.