syzbot


general protection fault in proc_flush_task

Status: fixed on 2018/01/27 14:55
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+d97f673cce9cfcac0a53a46127f5349b57d7ad3f@syzkaller.appspotmail.com
Fix commit: c0ee554906c3 pid: Handle failure to allocate the first pid in a pid namespace
First crash: 2397d, last: 2374d

Sample crash report:
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 3164 Comm: syz-executor2 Not tainted 4.15.0-rc3+ #224
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:proc_flush_task_mnt fs/proc/base.c:3027 [inline]
RIP: 0010:proc_flush_task+0x282/0x680 fs/proc/base.c:3099
RSP: 0018:ffff8801c93ff3f8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 0000000000000007 RSI: dffffc0000000000 RDI: ffff8801c93ff4ac
RBP: ffff8801c93ff510 R08: 0000000000000000 R09: 1ffff1003927fe12
R10: 0000000000000500 R11: 0000000000000000 R12: ffff8801c93ff4a8
R13: 0000000000000000 R14: ffff8801c0c12900 R15: ffff8801c93ff4e8
FS:  0000000002896940(0000) GS:ffff8801db500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff48f9d158 CR3: 00000001c7e91005 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
 release_task+0x258/0x1a40 kernel/exit.c:195
 wait_task_zombie kernel/exit.c:1161 [inline]
 wait_consider_task+0x2a10/0x3420 kernel/exit.c:1388
 do_wait_thread kernel/exit.c:1451 [inline]
 do_wait+0x427/0xa70 kernel/exit.c:1522
 kernel_wait4+0x1f5/0x370 kernel/exit.c:1665
 SYSC_wait4+0x134/0x140 kernel/exit.c:1677
 SyS_wait4+0x2c/0x40 kernel/exit.c:1673
 entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x40cdba
RSP: 002b:00007fff48f9d148 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: ffffffffffffffda RBX: 0000000002896914 RCX: 000000000040cdba
RDX: 0000000040000001 RSI: 00007fff48f9d16c RDI: ffffffffffffffff
RBP: 0000000000004fe3 R08: 0000000000000001 R09: 0000000002896940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000004fe3
R13: 000000000000000d R14: 00000000000f83c4 R15: 0000000000000001
Code: 48 89 fa 48 c1 ea 03 0f b6 0c 1a 48 89 fa 83 e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85 7b 03 00 00 41 89 47 c4 4c 89 e8 48 c1 e8 03 <80> 3c 18 00 0f 85 59 03 00 00 49 8b 7d 00 4c 89 e6 e8 88 95 e7 
RIP: proc_flush_task_mnt fs/proc/base.c:3027 [inline] RSP: ffff8801c93ff3f8
RIP: proc_flush_task+0x282/0x680 fs/proc/base.c:3099 RSP: ffff8801c93ff3f8
general protection fault: 0000 [#2] SMP KASAN
---[ end trace 29874269c9d5c326 ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 3152 Comm: syz-executor4 Tainted: G      D          4.15.0-rc3+ #224
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:proc_flush_task_mnt fs/proc/base.c:3027 [inline]
RIP: 0010:proc_flush_task+0x282/0x680 fs/proc/base.c:3099
RSP: 0018:ffff8801c7f373f8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 0000000000000007 RSI: dffffc0000000000 RDI: ffff8801c7f374ac
RBP: ffff8801c7f37510 R08: 0000000000000000 R09: 1ffff10038fe6e12
R10: 0000000000000500 R11: 0000000000000000 R12: ffff8801c7f374a8
R13: 0000000000000000 R14: ffff8801cab05700 R15: ffff8801c7f374e8
FS:  0000000001332940(0000) GS:ffff8801db400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffeef0049b8 CR3: 00000001cf1d0004 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 release_task+0x258/0x1a40 kernel/exit.c:195
 wait_task_zombie kernel/exit.c:1161 [inline]
 wait_consider_task+0x2a10/0x3420 kernel/exit.c:1388
 do_wait_thread kernel/exit.c:1451 [inline]
 do_wait+0x427/0xa70 kernel/exit.c:1522
 kernel_wait4+0x1f5/0x370 kernel/exit.c:1665
 SYSC_wait4+0x134/0x140 kernel/exit.c:1677
 SyS_wait4+0x2c/0x40 kernel/exit.c:1673
 entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x40cdba
RSP: 002b:00007ffeef0049a8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: ffffffffffffffda RBX: 0000000001332914 RCX: 000000000040cdba
RDX: 0000000040000001 RSI: 00007ffeef0049cc RDI: ffffffffffffffff
RBP: 0000000000004ffc R08: 0000000000000001 R09: 0000000001332940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000004ffc
R13: 000000000000000d R14: 00000000000f844c R15: 0000000000000001
Code: 48 89 fa 48 c1 ea 03 0f b6 0c 1a 48 89 fa 83 e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85 7b 03 00 00 41 89 47 c4 4c 89 e8 48 c1 e8 03 <80> 3c 18 00 0f 85 59 03 00 00 49 8b 7d 00 4c 89 e6 e8 88 95 e7 
RIP: proc_flush_task_mnt fs/proc/base.c:3027 [inline] RSP: ffff8801c7f373f8
RIP: proc_flush_task+0x282/0x680 fs/proc/base.c:3099 RSP: ffff8801c7f373f8
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2017/12/16 20:22 upstream f6f3732162b5 b6f0c91b .config console log report syz ci-upstream-kasan-gce
2017/11/23 05:04 net-next-old 0c86a6bd85ff ddf7b3e0 .config console log report syz ci-upstream-kasan-gce-386
* Struck through repros no longer work on HEAD.