validate_nla: 63 callbacks suppressed netlink: 'syz-executor.2': attribute type 4 has an invalid length. overlayfs: unrecognized mount option "subj_user=^" or missing value ====================================================== WARNING: possible circular locking dependency detected 4.19.211-syzkaller #0 Not tainted ------------------------------------------------------ Started in network mode syz-executor.4/20949 is trying to acquire lock: 0000000035dc509b (&ovl_i_mutex_dir_key[depth]){++++}, at: inode_lock_shared include/linux/fs.h:758 [inline] 0000000035dc509b (&ovl_i_mutex_dir_key[depth]){++++}, at: lookup_slow fs/namei.c:1688 [inline] 0000000035dc509b (&ovl_i_mutex_dir_key[depth]){++++}, at: walk_component+0x798/0xda0 fs/namei.c:1811 but task is already holding lock: 0000000078d6f35f (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds fs/exec.c:1419 [inline] 0000000078d6f35f (&sig->cred_guard_mutex){+.+.}, at: __do_execve_file+0x38c/0x2360 fs/exec.c:1762 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: Own node identity aaaaaaaaaa32, cluster identity 4711 -> #3 (&sig->cred_guard_mutex){+.+.}: lock_trace fs/proc/base.c:402 [inline] proc_pid_personality+0x4a/0x170 fs/proc/base.c:2938 Enabled bearer , priority 0 proc_single_show+0xeb/0x170 fs/proc/base.c:755 seq_read+0x4e0/0x11c0 fs/seq_file.c:232 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 do_preadv fs/read_write.c:1071 [inline] __do_sys_preadv fs/read_write.c:1121 [inline] __se_sys_preadv fs/read_write.c:1116 [inline] __x64_sys_preadv+0x22b/0x310 fs/read_write.c:1116 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #2 (&p->lock){+.+.}: seq_read+0x6b/0x11c0 fs/seq_file.c:164 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 -> #1 (sb_writers#7){.+.+}: 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:602 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 -> #0 (&ovl_i_mutex_dir_key[depth]){++++}: down_read+0x36/0x80 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:758 [inline] lookup_slow fs/namei.c:1688 [inline] walk_component+0x798/0xda0 fs/namei.c:1811 link_path_walk.part.0+0x901/0x1230 fs/namei.c:2142 link_path_walk fs/namei.c:2073 [inline] path_openat+0x1db/0x2df0 fs/namei.c:3536 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:1770 do_execveat_common fs/exec.c:1879 [inline] do_execve+0x35/0x50 fs/exec.c:1896 __do_sys_execve fs/exec.c:1977 [inline] __se_sys_execve fs/exec.c:1972 [inline] __x64_sys_execve+0x7c/0xa0 fs/exec.c:1972 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: &ovl_i_mutex_dir_key[depth] --> &p->lock --> &sig->cred_guard_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sig->cred_guard_mutex); lock(&p->lock); lock(&sig->cred_guard_mutex); lock(&ovl_i_mutex_dir_key[depth]); *** DEADLOCK *** 1 lock held by syz-executor.4/20949: #0: 0000000078d6f35f (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds fs/exec.c:1419 [inline] #0: 0000000078d6f35f (&sig->cred_guard_mutex){+.+.}, at: __do_execve_file+0x38c/0x2360 fs/exec.c:1762 stack backtrace: CPU: 0 PID: 20949 Comm: syz-executor.4 Not tainted 4.19.211-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/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 down_read+0x36/0x80 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:758 [inline] lookup_slow fs/namei.c:1688 [inline] walk_component+0x798/0xda0 fs/namei.c:1811 link_path_walk.part.0+0x901/0x1230 fs/namei.c:2142 link_path_walk fs/namei.c:2073 [inline] path_openat+0x1db/0x2df0 fs/namei.c:3536 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:1770 do_execveat_common fs/exec.c:1879 [inline] do_execve+0x35/0x50 fs/exec.c:1896 __do_sys_execve fs/exec.c:1977 [inline] __se_sys_execve fs/exec.c:1972 [inline] __x64_sys_execve+0x7c/0xa0 fs/exec.c:1972 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f43ca743fe9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f43c9098168 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 00007f43ca857030 RCX: 00007f43ca743fe9 RDX: 0000000020000900 RSI: 00000000200008c0 RDI: 0000000020000780 RBP: 00007f43ca79e08d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe73e06b6f R14: 00007f43c9098300 R15: 0000000000022000 overlayfs: unrecognized mount option "subj_user=^" or missing value netlink: 'syz-executor.2': attribute type 4 has an invalid length. Started in network mode Own node identity aaaaaaaaaa32, cluster identity 4711 Enabled bearer , priority 0 32-bit node address hash set to aaaa9800 Enabling of bearer rejected, already enabled Enabling of bearer rejected, already enabled 32-bit node address hash set to aaaa9800 UDF-fs: bad mount option "seclabel" or missing value UDF-fs: bad mount option "seclabel" or missing value UDF-fs: bad mount option "seclabel" or missing value UDF-fs: bad mount option "seclabel" or missing value UDF-fs: bad mount option "seclabel" or missing value UDF-fs: bad mount option "seclabel" or missing value UDF-fs: bad mount option "seclabel" or missing value UDF-fs: bad mount option "seclabel" or missing value UDF-fs: bad mount option "seclabel" or missing value UDF-fs: bad mount option "seclabel" or missing value UDF-fs: bad mount option "seclabel" or missing value UDF-fs: bad mount option "seclabel" or missing value UDF-fs: bad mount option "seclabel" or missing value UDF-fs: bad mount option "seclabel" or missing value EXT4-fs (loop3): mounted filesystem without journal. Opts: ,errors=continue overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value kauditd_printk_skb: 125 callbacks suppressed audit: type=1804 audit(1642496060.326:1204): pid=21369 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.2" name="/root/syzkaller-testdir438482045/syzkaller.k75SrM/1052/bus" dev="sda1" ino=14418 res=1 overlayfs: unrecognized mount option "" or missing value audit: type=1800 audit(1642496060.356:1205): pid=21369 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="bus" dev="sda1" ino=14418 res=0 overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value hub 9-0:1.0: USB hub found hub 9-0:1.0: 8 ports detected overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value audit: type=1804 audit(1642496061.316:1206): pid=21446 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.2" name="/root/syzkaller-testdir438482045/syzkaller.k75SrM/1053/bus" dev="sda1" ino=14762 res=1 audit: type=1800 audit(1642496061.316:1207): pid=21446 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="bus" dev="sda1" ino=14762 res=0 audit: type=1804 audit(1642496061.406:1208): pid=21449 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=ToMToU comm="syz-executor.2" name="/root/syzkaller-testdir438482045/syzkaller.k75SrM/1053/bus" dev="sda1" ino=14762 res=1 overlayfs: unrecognized mount option "" or missing value audit: type=1804 audit(1642496061.406:1209): pid=21446 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.2" name="/root/syzkaller-testdir438482045/syzkaller.k75SrM/1053/bus" dev="sda1" ino=14762 res=1 overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value audit: type=1800 audit(1642496061.406:1210): pid=21446 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="bus" dev="sda1" ino=14762 res=0 audit: type=1804 audit(1642496061.586:1211): pid=21470 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.2" name="/root/syzkaller-testdir438482045/syzkaller.k75SrM/1054/bus" dev="sda1" ino=14773 res=1 overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value audit: type=1800 audit(1642496061.586:1212): pid=21470 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="bus" dev="sda1" ino=14773 res=0 overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value hub 9-0:1.0: USB hub found hub 9-0:1.0: 8 ports detected hub 9-0:1.0: USB hub found hub 9-0:1.0: 8 ports detected overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value audit: type=1800 audit(1642496062.536:1213): pid=21534 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="syz-executor.2" name="bus" dev="sda1" ino=14777 res=0 overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value hub 9-0:1.0: USB hub found overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value hub 9-0:1.0: 8 ports detected overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value hub 9-0:1.0: USB hub found hub 9-0:1.0: 8 ports detected overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value hub 9-0:1.0: USB hub found hub 9-0:1.0: 8 ports detected overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value overlayfs: unrecognized mount option "" or missing value hub 9-0:1.0: USB hub found hub 9-0:1.0: 8 ports detected