syz-executor.2 (10443) used greatest stack depth: 23408 bytes left audit: type=1800 audit(1673586707.024:17): pid=10408 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.4" name="bus" dev="sda1" ino=13991 res=0 ====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.5/10356 is trying to acquire lock: 00000000cb1b16fa (&fs_info->qgroup_ioctl_lock){+.+.}, at: btrfs_qgroup_inherit+0xde/0x1c60 fs/btrfs/qgroup.c:2284 but task is already holding lock: 00000000a9a0b4f5 (sb_internal#2){.+.+}, at: sb_start_intwrite include/linux/fs.h:1626 [inline] 00000000a9a0b4f5 (sb_internal#2){.+.+}, at: start_transaction+0xa37/0xf90 fs/btrfs/transaction.c:528 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: audit: type=1804 audit(1673586707.104:18): pid=10426 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.2" name="/root/syzkaller-testdir361288564/syzkaller.SvgxpE/14/bus" dev="sda1" ino=13995 res=1 -> #1 (sb_internal#2){.+.+}: sb_start_intwrite include/linux/fs.h:1626 [inline] start_transaction+0xa37/0xf90 fs/btrfs/transaction.c:528 btrfs_quota_enable+0x169/0x10b0 fs/btrfs/qgroup.c:905 btrfs_ioctl_quota_ctl fs/btrfs/ioctl.c:5233 [inline] btrfs_ioctl+0x622c/0x76d0 fs/btrfs/ioctl.c:6021 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&fs_info->qgroup_ioctl_lock){+.+.}: __mutex_lock_common kernel/locking/mutex.c:937 [inline] __mutex_lock+0xd7/0x1190 kernel/locking/mutex.c:1078 btrfs_qgroup_inherit+0xde/0x1c60 fs/btrfs/qgroup.c:2284 create_subvol+0x3aa/0x1850 fs/btrfs/ioctl.c:617 btrfs_mksubvol+0xe1d/0x1160 fs/btrfs/ioctl.c:1007 btrfs_ioctl_snap_create_transid+0x2a7/0x430 fs/btrfs/ioctl.c:1771 btrfs_ioctl_snap_create_v2+0x2db/0x5d0 fs/btrfs/ioctl.c:1885 btrfs_ioctl+0x26f6/0x76d0 fs/btrfs/ioctl.c:5934 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 audit: type=1804 audit(1673586707.104:19): pid=10427 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.2" name="/root/syzkaller-testdir361288564/syzkaller.SvgxpE/14/bus" dev="sda1" ino=13995 res=1 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sb_internal#2); lock(&fs_info->qgroup_ioctl_lock); lock(sb_internal#2); lock(&fs_info->qgroup_ioctl_lock); *** DEADLOCK *** 4 locks held by syz-executor.5/10356: #0: 0000000090e92703 (sb_writers#16){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline] #0: 0000000090e92703 (sb_writers#16){.+.+}, at: mnt_want_write_file+0x63/0x1d0 fs/namespace.c:418 #1: 00000000349990af (&type->i_mutex_dir_key#8/1){+.+.}, at: btrfs_mksubvol+0x156/0x1160 fs/btrfs/ioctl.c:975 #2: 0000000054d6718d (&fs_info->subvol_sem){++++}, at: btrfs_mksubvol+0x35b/0x1160 fs/btrfs/ioctl.c:998 #3: 00000000a9a0b4f5 (sb_internal#2){.+.+}, at: sb_start_intwrite include/linux/fs.h:1626 [inline] #3: 00000000a9a0b4f5 (sb_internal#2){.+.+}, at: start_transaction+0xa37/0xf90 fs/btrfs/transaction.c:528 stack backtrace: CPU: 0 PID: 10356 Comm: syz-executor.5 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1222 check_prev_add kernel/locking/lockdep.c:1866 [inline] check_prevs_add kernel/locking/lockdep.c:1979 [inline] validate_chain kernel/locking/lockdep.c:2420 [inline] __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3416 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3908 __mutex_lock_common kernel/locking/mutex.c:937 [inline] __mutex_lock+0xd7/0x1190 kernel/locking/mutex.c:1078 btrfs_qgroup_inherit+0xde/0x1c60 fs/btrfs/qgroup.c:2284 create_subvol+0x3aa/0x1850 fs/btrfs/ioctl.c:617 btrfs_mksubvol+0xe1d/0x1160 fs/btrfs/ioctl.c:1007 btrfs_ioctl_snap_create_transid+0x2a7/0x430 fs/btrfs/ioctl.c:1771 btrfs_ioctl_snap_create_v2+0x2db/0x5d0 fs/btrfs/ioctl.c:1885 btrfs_ioctl+0x26f6/0x76d0 fs/btrfs/ioctl.c:5934 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fbbf8af50c9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fbbf7067168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fbbf8c14f80 RCX: 00007fbbf8af50c9 RDX: 0000000020002540 RSI: 0000000050009418 RDI: 0000000000000004 RBP: 00007fbbf8b50ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc2c36bb0f R14: 00007fbbf7067300 R15: 0000000000022000 EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue EXT4-fs (loop3): mounted filesystem without journal. Opts: ,errors=continue netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'. device batadv1 entered promiscuous mode 8021q: adding VLAN 0 to HW filter on device batadv1 EXT4-fs (loop2): mounted filesystem without journal. Opts: ,errors=continue netlink: 4 bytes leftover after parsing attributes in process `syz-executor.3'. device batadv1 entered promiscuous mode 8021q: adding VLAN 0 to HW filter on device batadv1 netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'. kauditd_printk_skb: 51 callbacks suppressed audit: type=1804 audit(1673586712.434:71): pid=10778 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir1809712273/syzkaller.Fau6IO/20/bus" dev="sda1" ino=14030 res=1 wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'. wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 audit: type=1800 audit(1673586712.474:72): pid=10778 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.4" name="bus" dev="sda1" ino=14030 res=0 audit: type=1804 audit(1673586712.784:73): pid=10735 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.4" name="/root/syzkaller-testdir1809712273/syzkaller.Fau6IO/20/bus" dev="sda1" ino=14030 res=1 audit: type=1804 audit(1673586712.814:74): pid=10735 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.4" name="/root/syzkaller-testdir1809712273/syzkaller.Fau6IO/20/bus" dev="sda1" ino=14030 res=1 audit: type=1804 audit(1673586712.924:75): pid=10795 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir1809712273/syzkaller.Fau6IO/21/bus" dev="sda1" ino=14030 res=1 netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'. audit: type=1800 audit(1673586712.924:76): pid=10795 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.4" name="bus" dev="sda1" ino=14030 res=0 audit: type=1804 audit(1673586712.954:77): pid=10795 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.4" name="/root/syzkaller-testdir1809712273/syzkaller.Fau6IO/21/bus" dev="sda1" ino=14030 res=1 audit: type=1804 audit(1673586712.954:78): pid=10795 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.4" name="/root/syzkaller-testdir1809712273/syzkaller.Fau6IO/21/bus" dev="sda1" ino=14030 res=1 audit: type=1804 audit(1673586713.174:79): pid=10836 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.4" name="/root/syzkaller-testdir1809712273/syzkaller.Fau6IO/22/bus" dev="sda1" ino=14030 res=1 wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50 audit: type=1800 audit(1673586713.174:80): pid=10836 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.4" name="bus" dev="sda1" ino=14030 res=0 wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50 wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50