bisecting fixing commit since f6d5cb9e2c06f7d583dd9f4f7cca21d13d78c32a
building syzkaller on abf9ba4fc75d9b29af15625d44dcfc1360fad3b7
testing commit f6d5cb9e2c06f7d583dd9f4f7cca21d13d78c32a with gcc (GCC) 8.1.0
kernel signature: 5578b5470d306eb8b71ef8a2ea9ee8a34b26cb85c90589bc2585877838a236af
run #0: crashed: KASAN: use-after-free Read in debugfs_remove
run #1: crashed: KASAN: use-after-free Read in debugfs_remove
run #2: crashed: KASAN: use-after-free Read in debugfs_remove
run #3: crashed: KASAN: use-after-free Read in debugfs_remove
run #4: crashed: general protection fault in debugfs_remove
run #5: crashed: KASAN: use-after-free Read in debugfs_remove
run #6: crashed: KASAN: use-after-free Read in debugfs_remove
run #7: crashed: KASAN: use-after-free Read in debugfs_remove
run #8: crashed: KASAN: use-after-free Read in debugfs_remove
run #9: crashed: KASAN: use-after-free Read in debugfs_remove
testing current HEAD f5d8eef067acee3fda37137f4a08c0d3f6427a8e
testing commit f5d8eef067acee3fda37137f4a08c0d3f6427a8e with gcc (GCC) 8.1.0
kernel signature: 267b8e049a4c7dc8b81a30d65768be620e8c78169b85d3d0a7b3301ebe329973
run #0: crashed: general protection fault in debugfs_remove
run #1: crashed: KASAN: use-after-free Read in debugfs_remove
run #2: crashed: KASAN: use-after-free Read in debugfs_remove
run #3: crashed: KASAN: use-after-free Read in debugfs_remove
run #4: crashed: KASAN: use-after-free Read in debugfs_remove
run #5: crashed: KASAN: use-after-free Read in debugfs_remove
run #6: crashed: KASAN: use-after-free Read in debugfs_remove
run #7: crashed: KASAN: use-after-free Read in debugfs_remove
run #8: crashed: KASAN: use-after-free Read in debugfs_remove
run #9: crashed: general protection fault in debugfs_remove
revisions tested: 2, total time: 24m24.584941548s (build: 17m37.206353164s, test: 6m11.204265066s)
the crash still happens on HEAD
commit msg: Linux 4.19.154
crash: general protection fault in debugfs_remove
blktrace: Concurrent blktraces are not allowed on loop0
blktrace: Concurrent blktraces are not allowed on loop0
blktrace: Concurrent blktraces are not allowed on loop0
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 7839 Comm: kworker/0:3 Not tainted 4.19.154-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events __blk_release_queue
RIP: 0010:__lock_acquire+0x220/0x47c0 kernel/locking/lockdep.c:3294
Code: 28 00 00 00 0f 85 d1 2d 00 00 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 a3 2f 00 00 49 81 7d 00 20 95 5c 89 0f 84 4a ff
RSP: 0018:ffff8880911bfa10 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: ffff8880a4fd0640 RCX: 0000000000000000
RDX: 0000000000000027 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffff8880911bfbf8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff8858f0cf R12: 0000000000000000
R13: 0000000000000138 R14: ffff8880a4fd0640 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880ba600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa2bd6cedb8 CR3: 000000009d099000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 lock_acquire+0x180/0x3a0 kernel/locking/lockdep.c:3907
 down_write+0x38/0x90 kernel/locking/rwsem.c:70
 inode_lock include/linux/fs.h:748 [inline]
 debugfs_remove+0x72/0xf0 fs/debugfs/inode.c:688
 blk_trace_free+0x30/0x130 kernel/trace/blktrace.c:315
 blk_trace_cleanup kernel/trace/blktrace.c:343 [inline]
 __blk_trace_remove+0x5c/0x80 kernel/trace/blktrace.c:356
 blk_trace_shutdown+0x67/0xc0 kernel/trace/blktrace.c:780
 __blk_release_queue+0x1f6/0x490 block/blk-sysfs.c:855
 process_one_work+0x7b9/0x15a0 kernel/workqueue.c:2155
 worker_thread+0x85/0xb60 kernel/workqueue.c:2298
 kthread+0x347/0x410 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Modules linked in:
---[ end trace cffb9599fda9d383 ]---
RIP: 0010:__lock_acquire+0x220/0x47c0 kernel/locking/lockdep.c:3294
Code: 28 00 00 00 0f 85 d1 2d 00 00 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 <80> 3c 02 00 0f 85 a3 2f 00 00 49 81 7d 00 20 95 5c 89 0f 84 4a ff
RSP: 0018:ffff8880911bfa10 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: ffff8880a4fd0640 RCX: 0000000000000000
RDX: 0000000000000027 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffff8880911bfbf8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff8858f0cf R12: 0000000000000000
R13: 0000000000000138 R14: ffff8880a4fd0640 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880ba600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa2bd6cedb8 CR3: 000000009d099000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400