WARNING: possible circular locking dependency detected
4.19.136-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.2/22332 is trying to acquire lock:
000000006d6b8924 (&sig->cred_guard_mutex){+.+.}, at: lock_trace fs/proc/base.c:402 [inline]
000000006d6b8924 (&sig->cred_guard_mutex){+.+.}, at: proc_pid_personality+0x4a/0x170 fs/proc/base.c:2926

but task is already holding lock:
00000000ead85456 (&p->lock){+.+.}, at: seq_read+0x6b/0x1160 fs/seq_file.c:161

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&p->lock){+.+.}:
       seq_read+0x6b/0x1160 fs/seq_file.c:161
       do_loop_readv_writev fs/read_write.c:701 [inline]
       do_loop_readv_writev fs/read_write.c:688 [inline]
       do_iter_read+0x471/0x630 fs/read_write.c:925
       vfs_readv+0xe5/0x150 fs/read_write.c:987
       kernel_readv fs/splice.c:362 [inline]
       default_file_splice_read+0x457/0xa00 fs/splice.c:417
       do_splice_to+0x10e/0x160 fs/splice.c:881
       splice_direct_to_actor+0x2b9/0x8d0 fs/splice.c:959
       do_splice_direct+0x1a7/0x270 fs/splice.c:1068
       do_sendfile+0x550/0xc30 fs/read_write.c:1447
       __do_sys_sendfile64 fs/read_write.c:1508 [inline]
       __se_sys_sendfile64+0x147/0x160 fs/read_write.c:1494
       do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
       entry_SYSCALL_64_after_hwframe+0x49/0xbe

-> #2 (sb_writers#3){.+.+}:
       sb_start_write include/linux/fs.h:1579 [inline]
       mnt_want_write+0x3a/0xb0 fs/namespace.c:360
       ovl_create_object+0x96/0x290 fs/overlayfs/dir.c:600
       lookup_open+0x893/0x1a20 fs/namei.c:3235
       do_last fs/namei.c:3327 [inline]
       path_openat+0x1094/0x2df0 fs/namei.c:3537
       do_filp_open+0x18c/0x3f0 fs/namei.c:3567
       do_sys_open+0x3b3/0x520 fs/open.c:1085
       do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
       entry_SYSCALL_64_after_hwframe+0x49/0xbe

-> #1 (&ovl_i_mutex_dir_key[depth]#2){++++}:
       inode_lock_shared include/linux/fs.h:758 [inline]
       do_last fs/namei.c:3326 [inline]
       path_openat+0x17ec/0x2df0 fs/namei.c:3537
       do_filp_open+0x18c/0x3f0 fs/namei.c:3567
       do_open_execat+0x11d/0x5b0 fs/exec.c:853
       __do_execve_file+0x1a8b/0x2360 fs/exec.c:1757
       do_execveat_common fs/exec.c:1866 [inline]
       do_execve+0x35/0x50 fs/exec.c:1883
       __do_sys_execve fs/exec.c:1964 [inline]
       __se_sys_execve fs/exec.c:1959 [inline]
       __x64_sys_execve+0x7c/0xa0 fs/exec.c:1959
       do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
       entry_SYSCALL_64_after_hwframe+0x49/0xbe

-> #0 (&sig->cred_guard_mutex){+.+.}:
       __mutex_lock_common kernel/locking/mutex.c:925 [inline]
       __mutex_lock+0xd7/0x1260 kernel/locking/mutex.c:1072
       lock_trace fs/proc/base.c:402 [inline]
       proc_pid_personality+0x4a/0x170 fs/proc/base.c:2926
       proc_single_show+0xeb/0x170 fs/proc/base.c:755
       seq_read+0x4be/0x1160 fs/seq_file.c:229
       do_loop_readv_writev fs/read_write.c:701 [inline]
       do_loop_readv_writev fs/read_write.c:688 [inline]
       do_iter_read+0x471/0x630 fs/read_write.c:925
       vfs_readv+0xe5/0x150 fs/read_write.c:987
       kernel_readv fs/splice.c:362 [inline]
       default_file_splice_read+0x457/0xa00 fs/splice.c:417
       do_splice_to+0x10e/0x160 fs/splice.c:881
       splice_direct_to_actor+0x2b9/0x8d0 fs/splice.c:959
       do_splice_direct+0x1a7/0x270 fs/splice.c:1068
       do_sendfile+0x550/0xc30 fs/read_write.c:1447
       __do_sys_sendfile64 fs/read_write.c:1508 [inline]
       __se_sys_sendfile64+0x147/0x160 fs/read_write.c:1494
       do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
       entry_SYSCALL_64_after_hwframe+0x49/0xbe

other info that might help us debug this:

Chain exists of:
  &sig->cred_guard_mutex --> sb_writers#3 --> &p->lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&p->lock);
                               lock(sb_writers#3);
                               lock(&p->lock);
  lock(&sig->cred_guard_mutex);

 *** DEADLOCK ***

1 lock held by syz-executor.2/22332:
 #0: 00000000ead85456 (&p->lock){+.+.}, at: seq_read+0x6b/0x1160 fs/seq_file.c:161

stack backtrace:
CPU: 1 PID: 22332 Comm: syz-executor.2 Not tainted 4.19.136-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2fe lib/dump_stack.c:118
 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1221
 check_prev_add kernel/locking/lockdep.c:1865 [inline]
 check_prevs_add kernel/locking/lockdep.c:1978 [inline]
 validate_chain kernel/locking/lockdep.c:2419 [inline]
 __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3415
 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3907
 __mutex_lock_common kernel/locking/mutex.c:925 [inline]
 __mutex_lock+0xd7/0x1260 kernel/locking/mutex.c:1072
 lock_trace fs/proc/base.c:402 [inline]
 proc_pid_personality+0x4a/0x170 fs/proc/base.c:2926
 proc_single_show+0xeb/0x170 fs/proc/base.c:755
 seq_read+0x4be/0x1160 fs/seq_file.c:229
 do_loop_readv_writev fs/read_write.c:701 [inline]
 do_loop_readv_writev fs/read_write.c:688 [inline]
 do_iter_read+0x471/0x630 fs/read_write.c:925
 vfs_readv+0xe5/0x150 fs/read_write.c:987
 kernel_readv fs/splice.c:362 [inline]
 default_file_splice_read+0x457/0xa00 fs/splice.c:417
 do_splice_to+0x10e/0x160 fs/splice.c:881
 splice_direct_to_actor+0x2b9/0x8d0 fs/splice.c:959
 do_splice_direct+0x1a7/0x270 fs/splice.c:1068
 do_sendfile+0x550/0xc30 fs/read_write.c:1447
 __do_sys_sendfile64 fs/read_write.c:1508 [inline]
 __se_sys_sendfile64+0x147/0x160 fs/read_write.c:1494
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45cc79
Code: 2d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 fb b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f6f735d8c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000026b80 RCX: 000000000045cc79
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000005
RBP: 000000000078bf48 R08: 0000000000000000 R09: 0000000000000000
R10: 0800000080004103 R11: 0000000000000246 R12: 000000000078bf0c
R13: 00007ffef7829a1f R14: 00007f6f735d99c0 R15: 000000000078bf0c
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
platform regulatory.0: Direct firmware load for regulatory.db failed with error -2
sg_write: process 4829 (syz-executor.5) changed security contexts after opening file descriptor, this is not allowed.
platform regulatory.0: Direct firmware load for regulatory.db failed with error -2
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg0] tag#361 FAILED Result: hostbyte=DID_ABORT driverbyte=DRIVER_OK
sd 0:0:1:0: [sg0] tag#361 CDB: Xdwrite
sd 0:0:1:0: [sg0] tag#361 CDB[00]: 50 c5 77 e7 d2 16 0a 54 76 fc cd af ad a8 6a 3e
sd 0:0:1:0: [sg0] tag#361 CDB[10]: 63 0b f3 bd 6b c0 5e a0 dd 9e 42 bf d4 2f 21 75
sd 0:0:1:0: [sg0] tag#361 CDB[20]: e9 e7 7c 8b 0f bc f2 61 30 3b c9 96 19 35 5e f4
sd 0:0:1:0: [sg0] tag#361 CDB[30]: ae 4f 9a c1 3b 7d 81 3f b8 c3 d5 a7 2b 8b 12 0c
sd 0:0:1:0: [sg0] tag#361 CDB[40]: 65 cc d3 4e b5 e5 2f 02 98 c2 8b 5d 95 a7 fe 18
sd 0:0:1:0: [sg0] tag#361 CDB[50]: 47 87 b7 15 01 96 52 42 3a 8f 19 79 54 71 7a 95
sd 0:0:1:0: [sg0] tag#361 CDB[60]: f6
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg0] tag#373 FAILED Result: hostbyte=DID_ABORT driverbyte=DRIVER_OK
sd 0:0:1:0: [sg0] tag#373 CDB: Xdwrite
sd 0:0:1:0: [sg0] tag#373 CDB[00]: 50 c5 77 e7 d2 16 0a 54 76 fc cd af ad a8 6a 3e
sd 0:0:1:0: [sg0] tag#373 CDB[10]: 63 0b f3 bd 6b c0 5e a0 dd 9e 42 bf d4 2f 21 75
sd 0:0:1:0: [sg0] tag#373 CDB[20]: e9 e7 7c 8b 0f bc f2 61 30 3b c9 96 19 35 5e f4
sd 0:0:1:0: [sg0] tag#373 CDB[30]: ae
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'.
device bridge1 entered promiscuous mode
bridge1: port 1(bridge_slave_0) entered blocking state
bridge1: port 1(bridge_slave_0) entered disabled state
device bridge_slave_0 entered promiscuous mode
bridge1: port 1(bridge_slave_0) entered blocking state
bridge1: port 1(bridge_slave_0) entered forwarding state
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
netlink: 4 bytes leftover after parsing attributes in process `syz-executor.5'.
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sd 0:0:1:0: [sg_rq_end_io] Sense Key : Illegal Request [current] 
sd 0:0:1:0: [sg_rq_end_io] Add. Sense: Invalid command operation code
sg_write: data in/out 167162/30 bytes for SCSI command 0xff-- guessing data in;
   program syz-executor.5 not setting count and/or reply_len properly