general protection fault in freeary

From: syzbot
Date: Sat Dec 08 2018 - 05:51:33 EST


Hello,

syzbot found the following crash on:

HEAD commit: 74c4a24df7ca Add linux-next specific files for 20181207
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=11a713d5400000
kernel config: https://syzkaller.appspot.com/x/.config?x=6e9413388bf37bed
dashboard link: https://syzkaller.appspot.com/bug?extid=9d8b6fa6ee7636f350c1
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16e19da3400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+9d8b6fa6ee7636f350c1@xxxxxxxxxxxxxxxxxxxxxxxxx

dmaengine-unmap-16 0KB 4KB
dmaengine-unmap-2 0KB 3KB
kasan: CONFIG_KASAN_INLINE enabled
skbuff_fclone_cache 5KB 7KB
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 21755 Comm: syz-executor0 Not tainted 4.20.0-rc5-next-20181207+ #163
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__list_del_entry_valid+0x84/0x100 lib/list_debug.c:51
Code: 0f 84 60 01 00 00 48 b8 00 02 00 00 00 00 ad de 49 39 c4 0f 84 39 01 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 75 5f 49 8b 14 24 48 39 da 0f 85 4e 01 00 00 49 8d 7d
RSP: 0018:ffff8881b5ea6ec0 EFLAGS: 00010a06
RAX: dffffc0000000000 RBX: ffffffff87dd7df8 RCX: ffffffff8341d7fe
RDX: 11699ffffec411b1 RSI: ffffffff8341d556 RDI: ffffffff87dd7e00
skbuff_head_cache 539KB 1706KB
RBP: ffff8881b5ea6ed8 R08: ffff8881baf76300 R09: fffff5200198e400
R10: fffff5200198e400 R11: ffffc9000cc72003 R12: 8b4cfffff6208d8b
R13: 48fffff618b58b48 R14: ffff8881b5ea72c0 R15: dffffc0000000000
FS: 000000000279f940(0000) GS:ffff8881dad00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000072c000 CR3: 00000001c031f000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__list_del_entry include/linux/list.h:117 [inline]
list_del include/linux/list.h:125 [inline]
unlink_queue ipc/sem.c:786 [inline]
freeary+0xe72/0x1a40 ipc/sem.c:1164
configfs_dir_cache 0KB 4KB
file_lock_cache 0KB 3KB
file_lock_ctx 0KB 3KB
fsnotify_mark_connector 43KB 55KB
free_ipcs+0x9f/0x1c0 ipc/namespace.c:112
sem_exit_ns+0x20/0x40 ipc/sem.c:237
free_ipc_ns ipc/namespace.c:120 [inline]
put_ipc_ns+0x66/0x180 ipc/namespace.c:152
net_namespace 52KB 52KB
free_nsproxy+0xcf/0x220 kernel/nsproxy.c:180
switch_task_namespaces+0xb3/0xd0 kernel/nsproxy.c:229
exit_task_namespaces+0x17/0x20 kernel/nsproxy.c:234
do_exit+0x1a48/0x2620 kernel/exit.c:866
shmem_inode_cache 5754KB 6042KB
task_delay_info 112KB 484KB
taskstats 152KB 163KB
proc_dir_entry 578KB 581KB
do_group_exit+0x177/0x440 kernel/exit.c:970
get_signal+0x8b0/0x1980 kernel/signal.c:2515
pde_opener 0KB 3KB
do_signal+0x9c/0x21c0 arch/x86/kernel/signal.c:816
seq_file 282KB 342KB
sigqueue 39KB 208KB
kernfs_node_cache 11484KB 11489KB
mnt_cache 5951KB 6436KB
exit_to_usermode_loop+0x2e5/0x380 arch/x86/entry/common.c:162
prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
filp 3938KB 6761KB
entry_SYSCALL_64_after_hwframe+0x49/0xbe
names_cache 99560KB 99598KB
RIP: 0033:0x459f39
Code: ff 48 85 f6 0f 84 27 8a fb ff 48 83 ee 10 48 89 4e 08 48 89 3e 48 89 d7 4c 89 c2 4d 89 c8 4c 8b 54 24 08 b8 38 00 00 00 0f 05 <48> 85 c0 0f 8c fe 89 fb ff 74 01 c3 31 ed 48 f7 c7 00 00 01 00 75
RSP: 002b:00007ffd923f9ef8 EFLAGS: 00000202 ORIG_RAX: 0000000000000038
RAX: fffffffffffffff4 RBX: 00007f99b9efc700 RCX: 0000000000459f39
RDX: 00007f99b9efc9d0 RSI: 00007f99b9efbdb0 RDI: 00000000003d0f00
iint_cache 87KB 91KB
RBP: 00007ffd923fa100 R08: 00007f99b9efc700 R09: 00007f99b9efc700
R10: 00007f99b9efc9d0 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffd923f9faf R14: 00007f99b9efc9c0 R15: 0000000000000001
Modules linked in:
---[ end trace 984887003f1a69a9 ]---
RIP: 0010:__list_del_entry_valid+0x84/0x100 lib/list_debug.c:51
key_jar 3KB 7KB
Code: 0f 84 60 01 00 00 48 b8 00 02 00 00 00 00 ad de 49 39 c4 0f 84 39 01 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1 ea 03 <80> 3c 02 00 75 5f 49 8b 14 24 48 39 da 0f 85 4e 01 00 00 49 8d 7d
RSP: 0018:ffff8881b5ea6ec0 EFLAGS: 00010a06
RAX: dffffc0000000000 RBX: ffffffff87dd7df8 RCX: ffffffff8341d7fe
RDX: 11699ffffec411b1 RSI: ffffffff8341d556 RDI: ffffffff87dd7e00
RBP: ffff8881b5ea6ed8 R08: ffff8881baf76300 R09: fffff5200198e400
uts_namespace 2KB 7KB
R10: fffff5200198e400 R11: ffffc9000cc72003 R12: 8b4cfffff6208d8b
R13: 48fffff618b58b48 R14: ffff8881b5ea72c0 R15: dffffc0000000000
FS: 000000000279f940(0000) GS:ffff8881dad00000(0000) knlGS:0000000000000000
nsproxy 63KB 75KB
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000072c000 CR3: 00000001c031f000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxxx

syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with syzbot.
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches