syzbot


BUG: unable to handle kernel NULL pointer dereference in smc_getsockopt

Status: fixed on 2018/05/16 09:57
Subsystems: net s390
[Documentation on labels]
Fix commit: 070204a34884 net/smc: keep clcsock reference in smc_tcp_listen_work()
First crash: 2148d, last: 2143d

Sample crash report:
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
BUG: unable to handle kernel NULL pointer dereference at 0000000000000028
PGD 80000001982d8067 P4D 80000001982d8067 PUD 198684067 PMD 0 
Oops: 0000 [#1] SMP PTI
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 4574 Comm: syz-executor302 Not tainted 4.17.0-rc3+ #88
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:smc_getsockopt+0xc6/0x1a0 net/smc/af_smc.c:1298
RSP: 0018:ffff8801988efd48 EFLAGS: 00010246
RAX: ffff8801994782d0 RBX: ffff88019a8988d8 RCX: ffff880000000000
RDX: ffff8801986e42d0 RSI: aaaaaaaaaaaab000 RDI: ffffea0000000000
RBP: ffff8801988efdb8 R08: 00000000200002c0 R09: 0000000000000002
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000028 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f78b7d91700(0000) GS:ffff88021fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000028 CR3: 0000000198d4a000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __sys_getsockopt+0x49b/0x560 net/socket.c:1940
 __do_sys_getsockopt net/socket.c:1951 [inline]
 __se_sys_getsockopt net/socket.c:1948 [inline]
 __x64_sys_getsockopt+0x15d/0x1c0 net/socket.c:1948
 do_syscall_64+0x154/0x220 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x4454f9
RSP: 002b:00007f78b7d90db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00000000006dac24 RCX: 00000000004454f9
RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00000000006dac20 R08: 00000000200002c0 R09: 0000000000000000
R10: 0000000020000040 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffeb80aeadf R14: 00007f78b7d919c0 R15: 0000000000000001
Code: 0f 85 d0 00 00 00 4d 8b 37 4c 89 ff e8 54 bc 0f f8 4c 8b 38 44 8b 22 4c 89 75 b0 4d 8d 6e 28 4d 85 ff 0f 85 ba 00 00 00 45 89 e6 <4d> 8b 65 00 4c 89 ef e8 2e bc 0f f8 49 83 c4 70 48 83 38 00 0f 
RIP: smc_getsockopt+0xc6/0x1a0 net/smc/af_smc.c:1298 RSP: ffff8801988efd48
CR2: 0000000000000028
---[ end trace fed8d275c1fcf6ec ]---

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/05/10 21:32 https://github.com/google/kmsan.git master 74ee2200b89f 12c7428a .config console log report syz C ci-upstream-kmsan-gce
2018/05/16 05:26 https://github.com/google/kmsan.git master 06b2df0593a8 68ce85f1 .config console log report ci-upstream-kmsan-gce
2018/05/15 03:03 https://github.com/google/kmsan.git master 450487484278 d2284dda .config console log report ci-upstream-kmsan-gce
2018/05/15 02:55 https://github.com/google/kmsan.git master 450487484278 d2284dda .config console log report ci-upstream-kmsan-gce
2018/05/14 22:01 https://github.com/google/kmsan.git master 450487484278 d2284dda .config console log report ci-upstream-kmsan-gce
2018/05/14 21:09 https://github.com/google/kmsan.git master 450487484278 d2284dda .config console log report ci-upstream-kmsan-gce
2018/05/11 04:54 https://github.com/google/kmsan.git master 74ee2200b89f 12c7428a .config console log report ci-upstream-kmsan-gce
2018/05/11 03:07 https://github.com/google/kmsan.git master 74ee2200b89f 12c7428a .config console log report ci-upstream-kmsan-gce
2018/05/10 21:04 https://github.com/google/kmsan.git master 74ee2200b89f 12c7428a .config console log report ci-upstream-kmsan-gce
* Struck through repros no longer work on HEAD.