syzbot


BUG: unable to handle kernel paging request in locks_remove_file

Status: closed as dup on 2018/11/16 20:43
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+1d200d0b1db9c9f449d0@syzkaller.appspotmail.com
First crash: 2237d, last: 2236d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
KASAN: use-after-free Read in locks_delete_block fs syz 4 2208d 2231d
Discussions (1)
Title Replies (including bot) Last reply
BUG: unable to handle kernel paging request in locks_remove_file 1 (2) 2018/11/16 20:42

Sample crash report:
kernel tried to execute NX-protected page - exploit attempt? (uid: 0)
BUG: unable to handle kernel paging request at ffff8801874af820
PGD be01067 P4D be01067 PUD 1cdce5063 PMD 1c1301063 PTE 80000001874af163
Oops: 0011 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 25895 Comm: syz-executor2 Not tainted 4.20.0-rc1-next-20181107+ #107
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:0xffff8801874af820
Code: 81 64 80 7a 25 bf 01 88 ff ff 1e 80 1d 08 00 00 00 00 fc 7a 25 bf 01 88 ff ff 1a 5f e9 30 00 f1 ff 1f b0 97 68 cc 01 88 ff ff <38> f9 4a 87 01 88 ff ff e0 ab cf 81 ff ff ff ff 98 7a 25 bf 01 88
RSP: 0018:ffff8801874af508 EFLAGS: 00010216
RAX: 0000000000040000 RBX: ffff8801874af820 RCX: ffffc90006782000
RDX: 00000000000004e2 RSI: ffffffff81ed5c9e RDI: ffff8801874af588
RBP: ffff8801874af6f0 R08: ffff88017da1a680 R09: ffffed003b5c5b67
R10: ffffed003b5c5b67 R11: ffff8801dae2db3b R12: ffff8801bf257a80
R13: ffff8801874af588 R14: 1ffff10030e95ea5 R15: dffffc0000000000
FS:  00007f0547a61700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff8801874af820 CR3: 00000001b79b2000 CR4: 00000000001426f0
Call Trace:
 locks_remove_file+0x148/0x5c0 fs/locks.c:2607
 __fput+0x2f0/0xa70 fs/file_table.c:271
 ____fput+0x15/0x20 fs/file_table.c:312
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 get_signal+0x1550/0x1970 kernel/signal.c:2347
 do_signal+0x9c/0x21c0 arch/x86/kernel/signal.c:816
 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
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457569
Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f0547a60c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000457569
RDX: 0000000020000100 RSI: 0000000040086602 RDI: 0000000000000003
RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0547a616d4
R13: 00000000004bf999 R14: 00000000004cfb48 R15: 00000000ffffffff
Modules linked in:
CR2: ffff8801874af820
---[ end trace a084de52bcce3aa4 ]---
RIP: 0010:0xffff8801874af820
Code: 81 64 80 7a 25 bf 01 88 ff ff 1e 80 1d 08 00 00 00 00 fc 7a 25 bf 01 88 ff ff 1a 5f e9 30 00 f1 ff 1f b0 97 68 cc 01 88 ff ff <38> f9 4a 87 01 88 ff ff e0 ab cf 81 ff ff ff ff 98 7a 25 bf 01 88
RSP: 0018:ffff8801874af508 EFLAGS: 00010216
RAX: 0000000000040000 RBX: ffff8801874af820 RCX: ffffc90006782000
RDX: 00000000000004e2 RSI: ffffffff81ed5c9e RDI: ffff8801874af588
RBP: ffff8801874af6f0 R08: ffff88017da1a680 R09: ffffed003b5c5b67
R10: ffffed003b5c5b67 R11: ffff8801dae2db3b R12: ffff8801bf257a80
R13: ffff8801874af588 R14: 1ffff10030e95ea5 R15: dffffc0000000000
FS:  00007f0547a61700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff8801874af820 CR3: 00000001b79b2000 CR4: 00000000001426f0

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/11/08 02:28 linux-next d881de30d29e e85d2a61 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/11/07 19:06 linux-next d881de30d29e e85d2a61 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/11/07 05:20 linux-next d881de30d29e 8bd6bd63 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/11/07 04:01 linux-next d881de30d29e 8bd6bd63 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.