====================================================== WARNING: possible circular locking dependency detected 4.14.215-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/10787 is trying to acquire lock: (sb_writers#3){.+.+}, at: [] sb_start_write include/linux/fs.h:1549 [inline] (sb_writers#3){.+.+}, at: [] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 but task is already holding lock: (&ovl_i_mutex_dir_key[depth]){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] (&ovl_i_mutex_dir_key[depth]){++++}, at: [] do_last fs/namei.c:3331 [inline] (&ovl_i_mutex_dir_key[depth]){++++}, at: [] path_openat+0xde2/0x2970 fs/namei.c:3569 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&ovl_i_mutex_dir_key[depth]){++++}: down_write_killable+0x37/0xb0 kernel/locking/rwsem.c:68 iterate_dir+0x387/0x5e0 fs/readdir.c:43 ovl_dir_read fs/overlayfs/readdir.c:306 [inline] ovl_dir_read_merged+0x2c5/0x430 fs/overlayfs/readdir.c:365 ovl_check_empty_dir+0x6e/0x200 fs/overlayfs/readdir.c:870 ovl_check_empty_and_clear+0x72/0xe0 fs/overlayfs/dir.c:306 ovl_remove_and_whiteout fs/overlayfs/dir.c:647 [inline] ovl_do_remove+0x565/0xb90 fs/overlayfs/dir.c:775 vfs_rmdir.part.0+0x144/0x390 fs/namei.c:3908 vfs_rmdir fs/namei.c:3893 [inline] do_rmdir+0x334/0x3c0 fs/namei.c:3968 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb -> #0 (sb_writers#3){.+.+}: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x64/0x260 fs/super.c:1342 sb_start_write include/linux/fs.h:1549 [inline] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 ovl_create_object+0x75/0x1d0 fs/overlayfs/dir.c:538 lookup_open+0x77a/0x1750 fs/namei.c:3241 do_last fs/namei.c:3334 [inline] path_openat+0xe08/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ovl_i_mutex_dir_key[depth]); lock(sb_writers#3); lock(&ovl_i_mutex_dir_key[depth]); lock(sb_writers#3); *** DEADLOCK *** 2 locks held by syz-executor.2/10787: #0: (sb_writers#14){.+.+}, at: [] sb_start_write include/linux/fs.h:1549 [inline] #0: (sb_writers#14){.+.+}, at: [] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 #1: (&ovl_i_mutex_dir_key[depth]){++++}, at: [] inode_lock include/linux/fs.h:719 [inline] #1: (&ovl_i_mutex_dir_key[depth]){++++}, at: [] do_last fs/namei.c:3331 [inline] #1: (&ovl_i_mutex_dir_key[depth]){++++}, at: [] path_openat+0xde2/0x2970 fs/namei.c:3569 stack backtrace: CPU: 1 PID: 10787 Comm: syz-executor.2 Not tainted 4.14.215-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x283 lib/dump_stack.c:58 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1258 check_prev_add kernel/locking/lockdep.c:1905 [inline] check_prevs_add kernel/locking/lockdep.c:2022 [inline] validate_chain kernel/locking/lockdep.c:2464 [inline] __lock_acquire+0x2e0e/0x3f20 kernel/locking/lockdep.c:3491 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:36 [inline] percpu_down_read include/linux/percpu-rwsem.h:59 [inline] __sb_start_write+0x64/0x260 fs/super.c:1342 sb_start_write include/linux/fs.h:1549 [inline] mnt_want_write+0x3a/0xb0 fs/namespace.c:386 ovl_create_object+0x75/0x1d0 fs/overlayfs/dir.c:538 lookup_open+0x77a/0x1750 fs/namei.c:3241 do_last fs/namei.c:3334 [inline] path_openat+0xe08/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45e219 RSP: 002b:00007ff0e0c19c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045e219 RDX: 000000000000275a RSI: 0000000020000080 RDI: 0000000000000004 RBP: 000000000119bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffd4e71021f R14: 00007ff0e0c1a9c0 R15: 000000000119bf8c overlayfs: upperdir is in-use by another mount, mount with '-o index=off' to override exclusive upperdir protection. ADFS-fs error (device loop5): adfs_fill_super: unable to read superblock ADFS-fs error (device loop5): adfs_fill_super: unable to read superblock ADFS-fs error (device loop5): adfs_fill_super: unable to read superblock ADFS-fs error (device loop5): adfs_fill_super: unable to read superblock ADFS-fs error (device loop5): adfs_fill_super: unable to read superblock input: syz1 as /devices/virtual/input/input7 input: syz1 as /devices/virtual/input/input9 input: syz1 as /devices/virtual/input/input10 input: syz1 as /devices/virtual/input/input11 input: syz1 as /devices/virtual/input/input12 input: syz1 as /devices/virtual/input/input13 input: syz1 as /devices/virtual/input/input14 audit: type=1800 audit(1610883685.426:2): pid=11112 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.3" name="file0" dev="sda1" ino=15862 res=0 TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. audit: type=1800 audit(1610883685.836:3): pid=11133 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.3" name="file0" dev="sda1" ino=15862 res=0 audit: type=1800 audit(1610883685.876:4): pid=11137 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.1" name="file0" dev="sda1" ino=15863 res=0 TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. audit: type=1800 audit(1610883686.096:5): pid=11158 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.3" name="file0" dev="sda1" ino=15862 res=0 TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. audit: type=1800 audit(1610883686.166:6): pid=11163 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.1" name="file0" dev="sda1" ino=15863 res=0 audit: type=1800 audit(1610883686.776:7): pid=11180 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.3" name="file0" dev="sda1" ino=15862 res=0 TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. audit: type=1800 audit(1610883686.806:8): pid=11181 uid=0 auid=0 ses=4 op="collect_data" cause="failed(directio)" comm="syz-executor.1" name="file0" dev="sda1" ino=15863 res=0 EXT4-fs (loop1): ext4_check_descriptors: Checksum for group 0 failed (60935!=0) EXT4-fs (loop1): orphan cleanup on readonly fs EXT4-fs error (device loop1): ext4_free_inode:286: comm syz-executor.1: reserved or nonexistent inode 3 EXT4-fs warning (device loop1): ext4_enable_quotas:5755: Failed to enable quota tracking (type=-1, err=-13). Please run e2fsck to fix. EXT4-fs (loop1): Cannot turn on quotas: error -13 EXT4-fs (loop1): mounted filesystem without journal. Opts: ,errors=continue hid-generic 0000:0000:0000.0001: item fetching failed at offset 0/1 UHID_CREATE from different security context by process 128 (syz-executor.3), this is not allowed. hid-generic: probe of 0000:0000:0000.0001 failed with error -22 hid-generic 0000:0000:0000.0002: item fetching failed at offset 0/1 hid-generic: probe of 0000:0000:0000.0002 failed with error -22 hid-generic 0000:0000:0000.0003: item fetching failed at offset 0/1 hid-generic 0000:0000:0000.0004: item fetching failed at offset 0/1 hid-generic: probe of 0000:0000:0000.0003 failed with error -22 hid-generic: probe of 0000:0000:0000.0004 failed with error -22 hid-generic 0000:0000:0000.0005: item fetching failed at offset 0/1 hid-generic 0000:0000:0000.0006: item fetching failed at offset 0/1 hid-generic: probe of 0000:0000:0000.0005 failed with error -22 hid-generic: probe of 0000:0000:0000.0006 failed with error -22 hid-generic 0000:0000:0000.0007: item fetching failed at offset 0/1 hid-generic: probe of 0000:0000:0000.0007 failed with error -22 hid-generic 0000:0000:0000.0008: item fetching failed at offset 0/1 hid-generic: probe of 0000:0000:0000.0008 failed with error -22 audit: type=1804 audit(1610883688.026:9): pid=11319 uid=0 auid=0 ses=4 op="invalid_pcr" cause="ToMToU" comm="syz-executor.3" name="/root/syzkaller-testdir350348420/syzkaller.e7tflB/46/file0" dev="sda1" ino=15872 res=1