syzbot


BUG: unable to handle kernel NULL pointer dereference in sctp_stream_free

Status: fixed on 2018/01/31 00:24
Subsystems: sctp
[Documentation on labels]
Reported-by: syzbot+5a73b85ba48546cea8ed105946d67a37b4495724@syzkaller.appspotmail.com
Fix commit: 79d0895140e9 sctp: fix error path in sctp_stream_init
First crash: 2375d, last: 2374d

Sample crash report:
RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452a09
RDX: 0000000000000010 RSI: 00000000200ba000 RDI: 0000000000000013
RBP: 000000000000004e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006ed7f0
R13: 0000000000000014 R14: 000000000071bf00 R15: ffffffffffffffff
BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
IP: sctp_stream_free+0x38/0x70 net/sctp/stream.c:209
PGD 1fff84067 P4D 1fff84067 PUD 1fc97b067 PMD 0 
Oops: 0000 [#1] SMP
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 17287 Comm: syz-executor2 Not tainted 4.15.0-rc3-next-20171214+ #67
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:sctp_stream_free+0x38/0x70 net/sctp/stream.c:209
RSP: 0018:ffffc90000f87a28 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff82407e51
RDX: 000000000000b1ed RSI: ffffc90001031000 RDI: ffff88020f8126d8
RBP: ffffc90000f87a40 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88020f8126d8 R14: ffff8802157464b0 R15: ffff8801fa982000
FS:  00007fe140a3f700(0000) GS:ffff88021fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020616ff8 CR3: 0000000200d69003 CR4: 00000000001606f0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 sctp_association_free+0xd8/0x270 net/sctp/associola.c:367
 sctp_sf_do_unexpected_init.isra.30+0x25e/0x530 net/sctp/sm_statefuns.c:1589
 sctp_sf_do_5_2_2_dupinit+0x35/0x40 net/sctp/sm_statefuns.c:1646
 sctp_do_sm+0x80/0x1dc0 net/sctp/sm_sideeffect.c:1190
 sctp_endpoint_bh_rcv+0x142/0x2a0 net/sctp/endpointola.c:456
 sctp_inq_push+0x6a/0xb0 net/sctp/inqueue.c:95
 sctp_backlog_rcv+0x61/0x3a0 net/sctp/input.c:350
 sk_backlog_rcv include/net/sock.h:907 [inline]
 __release_sock+0x85/0x160 net/core/sock.c:2264
 release_sock+0x37/0xe0 net/core/sock.c:2779
 sctp_connect+0x6c/0x80 net/sctp/socket.c:4333
 inet_dgram_connect+0x78/0xb0 net/ipv4/af_inet.c:541
 SYSC_connect+0xaf/0x130 net/socket.c:1619
 SyS_connect+0x24/0x30 net/socket.c:1600
 entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x452a09
RSP: 002b:00007fe140a3ec58 EFLAGS: 00000212 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452a09
RDX: 0000000000000010 RSI: 00000000200ba000 RDI: 0000000000000013
RBP: 000000000000004e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006ed7f0
R13: 0000000000000014 R14: 000000000071bf00 R15: ffffffffffffffff
Code: 0f 25 eb fe 4c 89 ef e8 c7 3c 00 00 4c 89 ef ff 50 20 66 41 83 7d 10 00 74 28 45 31 e4 31 db e8 ef 24 eb fe 49 8b 45 00 83 c3 01 <4a> 8b 7c 20 08 49 83 c4 18 e8 ea 5d fd fe 41 0f b7 45 10 39 d8 
RIP: sctp_stream_free+0x38/0x70 net/sctp/stream.c:209 RSP: ffffc90000f87a28
CR2: 0000000000000008
---[ end trace 5fbb25ea4389478d ]---

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2017/12/18 16:48 linux-next 6084b576dca2 1c4160ef .config console log report ci-upstream-next-kasan-gce
2017/12/17 22:11 linux-next 6084b576dca2 d5beb42a .config console log report ci-upstream-next-kasan-gce
* Struck through repros no longer work on HEAD.