Subject: BUG: spinlock bad magic (2)

From: syzbot <[email-masked]>
Date: Mon, 18 Dec 2017 04:36:00 -0800

Hello,

syzkaller hit the following crash on  
6084b576dca2e898f5c101baef151f7bfdbb606d
git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master
compiler: gcc (GCC) 7.1.1 20170620
.config is attached
Raw console output is attached.

Unfortunately, I don't have any reproducer for this bug yet.

netlink: 9 bytes leftover after parsing attributes in process  
`syz-executor1'.
QAT: Invalid ioctl
QAT: Invalid ioctl
BUG: spinlock bad magic on CPU#1, syz-executor3/15866
  lock: 0xffff8802156c5c30, .magic: 00000000, .owner: <none>/-1, .owner_cpu:  
0
CPU: 1 PID: 15866 Comm: syz-executor3 Not tainted 4.15.0-rc3-next-20171214+  
#67
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:17 [inline]
  dump_stack+0xe9/0x14b lib/dump_stack.c:53
  spin_dump+0x73/0xd0 kernel/locking/spinlock_debug.c:67
  spin_bug kernel/locking/spinlock_debug.c:75 [inline]
  debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline]
  do_raw_spin_lock+0x6d/0xc0 kernel/locking/spinlock_debug.c:112
  __raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline]
  _raw_spin_lock+0x32/0x40 kernel/locking/spinlock.c:144
  spin_lock include/linux/spinlock.h:310 [inline]
  rds_send_queue_rm+0x156/0x1e4 net/rds/send.c:850
  rds_sendmsg+0x689/0xcb0 net/rds/send.c:1158
  sock_sendmsg_nosec net/socket.c:636 [inline]
  sock_sendmsg+0x51/0x70 net/socket.c:646
  ___sys_sendmsg+0x35e/0x3b0 net/socket.c:2026
  __sys_sendmsg+0x50/0x90 net/socket.c:2060
  SYSC_sendmsg net/socket.c:2071 [inline]
  SyS_sendmsg+0x2d/0x50 net/socket.c:2067
  entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x452a39
RSP: 002b:00007f1efd185c58 EFLAGS: 00000212 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 0000000000452a39
RDX: 0000000000000000 RSI: 0000000020159fc8 RDI: 0000000000000017
RBP: 0000000000000020 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006ee3a0
R13: 00000000ffffffff R14: 00007f1efd1866d4 R15: 0000000000000000
BUG: unable to handle kernel NULL pointer dereference at 0000000000000028
IP: rds_send_xmit+0x80/0x930 net/rds/send.c:186
PGD 1da7eb067 P4D 1da7eb067 PUD 1d9f6b067 PMD 0
Oops: 0000 [#1] SMP
Dumping ftrace buffer:
    (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 15866 Comm: syz-executor3 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:rds_send_xmit+0x80/0x930 net/rds/send.c:186
RSP: 0018:ffffc90000ecfbc8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffffff83184bc0 RCX: ffffffff8241b25c
RDX: 0000000000010000 RSI: ffffc90005854000 RDI: ffff8802156c5c00
RBP: ffffc90000ecfc30 R08: ffff88021fd1bd00 R09: ffffe8ffffd0f6f0
R10: ffffc90000ecfac0 R11: 0000000000000000 R12: 0000000000000000
R13: ffff8802156c5c00 R14: ffff88021203ecc0 R15: ffff8802156c5c00
FS:  00007f1efd186700(0000) GS:ffff88021fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffdb56bfc0 CR3: 00000001da25d000 CR4: 00000000001426f0
Call Trace:
  rds_sendmsg+0xb22/0xcb0 net/rds/send.c:1189
  sock_sendmsg_nosec net/socket.c:636 [inline]
  sock_sendmsg+0x51/0x70 net/socket.c:646
  ___sys_sendmsg+0x35e/0x3b0 net/socket.c:2026
  __sys_sendmsg+0x50/0x90 net/socket.c:2060
  SYSC_sendmsg net/socket.c:2071 [inline]
  SyS_sendmsg+0x2d/0x50 net/socket.c:2067
  entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x452a39
RSP: 002b:00007f1efd185c58 EFLAGS: 00000212 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 0000000000452a39
RDX: 0000000000000000 RSI: 0000000020159fc8 RDI: 0000000000000017
RBP: 0000000000000020 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006ee3a0
R13: 00000000ffffffff R14: 00007f1efd1866d4 R15: 0000000000000000
Code: 00 00 00 48 83 c0 01 48 89 45 a0 49 89 85 a8 00 00 00 41 8b 85 a0 00  
00 00 83 f8 03 0f 85 4f 08 00 00 e8 e4 f0 e9 fe 48 8b 45 b8 <48> 8b 40 28  
48 8b 58 58 48 85 db 74 0a e8 ce f0 e9 fe 4c 89 ef
RIP: rds_send_xmit+0x80/0x930 net/rds/send.c:186 RSP: ffffc90000ecfbc8
CR2: 0000000000000028
---[ end trace 5bd8beb2036e5145 ]---

---
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