syzbot has found a reproducer for the following issue on: HEAD commit: ce4c854ee868 Merge tag 'for-5.18-rc1-tag' of git://git.ker.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=16258680f00000 kernel config: https://syzkaller.appspot.com/x/.config?x=595bcd2109a73f9c dashboard link: https://syzkaller.appspot.com/bug?extid=17404da5afdf21e8d612 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13b7765b700000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16de6637700000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+17404da5afdf21e8d612@xxxxxxxxxxxxxxxxxxxxxxxxx general protection fault, probably for non-canonical address 0xdffffc000000002a: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000150-0x0000000000000157] CPU: 1 PID: 3623 Comm: udevd Not tainted 5.18.0-rc1-syzkaller-00009-gce4c854ee868 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_acquire+0xd85/0x56c0 kernel/locking/lockdep.c:4899 Code: 1a 0e 41 be 01 00 00 00 0f 86 c8 00 00 00 89 05 21 8d 1a 0e e9 bd 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 15 31 00 00 48 81 3b 20 d4 22 8f 0f 84 4f f3 ff RSP: 0018:ffffc90003b5f9f0 EFLAGS: 00010002 RAX: dffffc0000000000 RBX: 0000000000000150 RCX: 0000000000000000 RDX: 000000000000002a RSI: 0000000000000000 RDI: 0000000000000150 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: ffff888079c50000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007faa8035a840(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000561474c18580 CR3: 0000000019f83000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> lock_acquire kernel/locking/lockdep.c:5641 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5606 down_write+0x90/0x150 kernel/locking/rwsem.c:1514 inode_lock include/linux/fs.h:748 [inline] simple_recursive_removal+0x171/0x830 fs/libfs.c:276 debugfs_remove fs/debugfs/inode.c:742 [inline] debugfs_remove+0x59/0x80 fs/debugfs/inode.c:736 blk_mq_debugfs_unregister_queue_rqos+0x34/0x70 block/blk-mq-debugfs.c:840 rq_qos_exit+0x1e/0xf0 block/blk-rq-qos.c:297 disk_release_mq block/genhd.c:1142 [inline] disk_release+0x191/0x420 block/genhd.c:1168 device_release+0x9f/0x240 drivers/base/core.c:2229 kobject_cleanup lib/kobject.c:705 [inline] kobject_release lib/kobject.c:736 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1c8/0x540 lib/kobject.c:753 put_device+0x1b/0x30 drivers/base/core.c:3512 blkdev_close+0x64/0x80 block/fops.c:512 __fput+0x277/0x9d0 fs/file_table.c:317 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:169 [inline] exit_to_user_mode_prepare+0x23c/0x250 kernel/entry/common.c:201 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:294 do_syscall_64+0x42/0x80 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7faa7ff25fc3 Code: 48 ff ff ff b8 ff ff ff ff e9 3e ff ff ff 66 0f 1f 84 00 00 00 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 RSP: 002b:00007fff33290db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 00007faa8035a6a8 RCX: 00007faa7ff25fc3 RDX: 000000000000001c RSI: 00007fff332905b8 RDI: 0000000000000008 RBP: 0000561474c196f0 R08: 0000000000000007 R09: 0000561474c22c30 R10: 00007faa7ffb4fc0 R11: 0000000000000246 R12: 0000000000000002 R13: 0000561474bf8aa0 R14: 0000000000000008 R15: 0000561474bef910 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__lock_acquire+0xd85/0x56c0 kernel/locking/lockdep.c:4899 Code: 1a 0e 41 be 01 00 00 00 0f 86 c8 00 00 00 89 05 21 8d 1a 0e e9 bd 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 15 31 00 00 48 81 3b 20 d4 22 8f 0f 84 4f f3 ff RSP: 0018:ffffc90003b5f9f0 EFLAGS: 00010002 RAX: dffffc0000000000 RBX: 0000000000000150 RCX: 0000000000000000 RDX: 000000000000002a RSI: 0000000000000000 RDI: 0000000000000150 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: ffff888079c50000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007faa8035a840(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000561474c18580 CR3: 0000000019f83000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 1a 0e sbb (%rsi),%cl 2: 41 be 01 00 00 00 mov $0x1,%r14d 8: 0f 86 c8 00 00 00 jbe 0xd6 e: 89 05 21 8d 1a 0e mov %eax,0xe1a8d21(%rip) # 0xe1a8d35 14: e9 bd 00 00 00 jmpq 0xd6 19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 20: fc ff df 23: 48 89 da mov %rbx,%rdx 26: 48 c1 ea 03 shr $0x3,%rdx * 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2e: 0f 85 15 31 00 00 jne 0x3149 34: 48 81 3b 20 d4 22 8f cmpq $0xffffffff8f22d420,(%rbx) 3b: 0f .byte 0xf 3c: 84 4f f3 test %cl,-0xd(%rdi) 3f: ff .byte 0xff
