syzbot


possible deadlock in process_measurement

Status: upstream: reported C repro on 2023/09/04 07:52
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+797f2199fb8d6d24883b@syzkaller.appspotmail.com
First crash: 269d, last: 194d
Fix commit to backport (bisect log) :
tree: upstream
commit a0e6a017ab56936c0405fe914a793b241ed25ee0
Author: MaΓ­ra Canal <mcanal@igalia.com>
Date: Tue May 23 12:32:08 2023 +0000

  drm/vkms: Fix race-condition between the hrtimer and the atomic commit

  
Bug presence (2)
Date Name Commit Repro Result
2023/09/04 linux-5.15.y (ToT) 8f790700c974 C [report] possible deadlock in mnt_want_write
2023/09/04 upstream (ToT) 708283abf896 C Didn't crash
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream possible deadlock in process_measurement (2) integrity lsm C done done 56 1273d 1640d 15/26 fixed on 2021/01/06 01:14
upstream possible deadlock in process_measurement (3) overlayfs C error 223 209d 1116d 0/26 closed as dup on 2023/06/06 09:59
linux-4.19 possible deadlock in process_measurement 156 624d 1596d 0/1 auto-obsoleted due to no activity on 2023/01/11 22:20
upstream possible deadlock in process_measurement lsm integrity C 51 1821d 2054d 0/26 closed as invalid on 2019/07/15 16:35
linux-6.1 possible deadlock in process_measurement origin:lts-only C unreliable 8 194d 271d 0/3 upstream: reported C repro on 2023/09/02 00:54
Fix bisection attempts (1)
Created Duration User Patch Repo Result
2023/09/05 09:13 6h35m fix candidate upstream job log (1)

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
5.15.130-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor298/3684 is trying to acquire lock:
ffff8880198e6740 (
&iint->mutex){+.+.}-{3:3}, at: process_measurement+0x733/0x1d60 security/integrity/ima/ima_main.c:260

but task is already holding lock:
ffff888023a72460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (sb_writers#5){.+.+}-{0:0}:
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1742 [inline]
       sb_start_write+0x4f/0x1c0 include/linux/fs.h:1812
       mnt_want_write+0x3b/0x80 fs/namespace.c:377
       ovl_maybe_copy_up+0x111/0x180 fs/overlayfs/copy_up.c:1076
       ovl_open+0xa4/0x200 fs/overlayfs/file.c:150
       do_dentry_open+0x807/0xfb0 fs/open.c:826
       vfs_open fs/open.c:956 [inline]
       dentry_open+0xc6/0x120 fs/open.c:972
       ima_calc_file_hash+0x15f/0x1c00 security/integrity/ima/ima_crypto.c:558
       ima_collect_measurement+0x293/0x530 security/integrity/ima/ima_api.c:254
       process_measurement+0x1038/0x1d60 security/integrity/ima/ima_main.c:337
       ima_file_check+0xf3/0x180 security/integrity/ima/ima_main.c:519
       do_open fs/namei.c:3540 [inline]
       path_openat+0x2745/0x2f20 fs/namei.c:3672
       do_filp_open+0x21c/0x460 fs/namei.c:3699
       do_sys_openat2+0x13b/0x500 fs/open.c:1211
       do_sys_open fs/open.c:1227 [inline]
       __do_sys_open fs/open.c:1235 [inline]
       __se_sys_open fs/open.c:1231 [inline]
       __x64_sys_open+0x221/0x270 fs/open.c:1231
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x61/0xcb

-> #0 (&iint->mutex){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain+0x1646/0x58b0 kernel/locking/lockdep.c:3787
       __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5011
       lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
       __mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
       __mutex_lock kernel/locking/mutex.c:729 [inline]
       mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
       process_measurement+0x733/0x1d60 security/integrity/ima/ima_main.c:260
       ima_file_check+0xf3/0x180 security/integrity/ima/ima_main.c:519
       do_open fs/namei.c:3540 [inline]
       path_openat+0x2745/0x2f20 fs/namei.c:3672
       do_filp_open+0x21c/0x460 fs/namei.c:3699
       do_sys_openat2+0x13b/0x500 fs/open.c:1211
       do_sys_open fs/open.c:1227 [inline]
       __do_sys_openat fs/open.c:1243 [inline]
       __se_sys_openat fs/open.c:1238 [inline]
       __x64_sys_openat+0x243/0x290 fs/open.c:1238
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x61/0xcb

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(sb_writers#5);
                               lock(&iint->mutex);
                               lock(sb_writers#5);
  lock(&iint->mutex);

 *** DEADLOCK ***

1 lock held by syz-executor298/3684:
 #0: ffff888023a72460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377

stack backtrace:
CPU: 1 PID: 3684 Comm: syz-executor298 Not tainted 5.15.130-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133
 check_prev_add kernel/locking/lockdep.c:3053 [inline]
 check_prevs_add kernel/locking/lockdep.c:3172 [inline]
 validate_chain+0x1646/0x58b0 kernel/locking/lockdep.c:3787
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5011
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5622
 __mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 process_measurement+0x733/0x1d60 security/integrity/ima/ima_main.c:260
 ima_file_check+0xf3/0x180 security/integrity/ima/ima_main.c:519
 do_open fs/namei.c:3540 [inline]
 path_openat+0x2745/0x2f20 fs/namei.c:3672
 do_filp_open+0x21c/0x460 fs/namei.c:3699
 do_sys_openat2+0x13b/0x500 fs/open.c:1211
 do_sys_open fs/open.c:1227 [inline]
 __do_sys_openat fs/open.c:1243 [inline]
 __se_sys_openat fs/open.c:1238 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1238
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fde8d9cf5b9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 18 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fde8656a218 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fde8da5d6b8 RCX: 00007fde8d9cf5b9
RDX: 000000000000275a RSI: 0000000020000080 RDI: 00000000ffffff9c
RBP: 00007fde8da5d6b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fde8da298e0
R13: 0031656c69662f2e R14: 6e6f3d7865646e69 R15: 0079616c7265766f
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/09/04 09:46 linux-5.15.y 8f790700c974 696ea0d2 .config console log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan possible deadlock in process_measurement
2023/11/18 14:06 linux-5.15.y 80529b4968a8 cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in process_measurement
2023/09/05 09:35 linux-5.15.y 8f790700c974 0b6286dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in process_measurement
2023/09/04 07:52 linux-5.15.y 8f790700c974 696ea0d2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan possible deadlock in process_measurement
* Struck through repros no longer work on HEAD.