binder: 18594:18596 ioctl 40046207 0 returned -16 input: syz1 as /devices/virtual/input/input13 audit: type=1400 audit(1591045805.839:190): avc: denied { dac_override } for pid=18628 comm="syz-executor.2" capability=1 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=cap_userns permissive=1 ====================================================== WARNING: possible circular locking dependency detected 4.14.182-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/18622 is trying to acquire lock: (&sig->cred_guard_mutex){+.+.}, at: [] lock_trace+0x3f/0xc0 fs/proc/base.c:407 but task is already holding lock: (&p->lock){+.+.}, at: [] seq_read+0xba/0x1130 fs/seq_file.c:165 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&p->lock){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xe8/0x1430 kernel/locking/mutex.c:893 seq_read+0xba/0x1130 fs/seq_file.c:165 proc_reg_read+0xf2/0x160 fs/proc/inode.c:217 do_loop_readv_writev fs/read_write.c:695 [inline] do_loop_readv_writev fs/read_write.c:682 [inline] do_iter_read+0x3e3/0x5a0 fs/read_write.c:919 vfs_readv+0xd3/0x130 fs/read_write.c:981 kernel_readv fs/splice.c:361 [inline] default_file_splice_read+0x41d/0x870 fs/splice.c:416 do_splice_to+0xfb/0x150 fs/splice.c:880 splice_direct_to_actor+0x20a/0x730 fs/splice.c:952 do_splice_direct+0x164/0x210 fs/splice.c:1061 do_sendfile+0x469/0xaf0 fs/read_write.c:1441 SYSC_sendfile64 fs/read_write.c:1502 [inline] SyS_sendfile64+0xff/0x110 fs/read_write.c:1488 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb -> #2 (sb_writers#3){.+.+}: 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+0x1a1/0x2e0 fs/super.c:1363 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+0x756/0x1700 fs/namei.c:3241 do_last fs/namei.c:3334 [inline] path_openat+0xddf/0x2aa0 fs/namei.c:3569 do_filp_open+0x18e/0x250 fs/namei.c:3603 do_sys_open+0x292/0x3e0 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb -> #1 (&ovl_i_mutex_dir_key[depth]#2){++++}: down_read+0x37/0xa0 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:729 [inline] do_last fs/namei.c:3333 [inline] path_openat+0x148c/0x2aa0 fs/namei.c:3569 do_filp_open+0x18e/0x250 fs/namei.c:3603 do_open_execat+0xda/0x440 fs/exec.c:849 do_execveat_common.isra.0+0x680/0x1c50 fs/exec.c:1742 do_execve fs/exec.c:1847 [inline] SYSC_execve fs/exec.c:1928 [inline] SyS_execve+0x34/0x40 fs/exec.c:1923 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb -> #0 (&sig->cred_guard_mutex){+.+.}: lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xe8/0x1430 kernel/locking/mutex.c:893 lock_trace+0x3f/0xc0 fs/proc/base.c:407 proc_pid_syscall+0x81/0x1f0 fs/proc/base.c:639 proc_single_show+0xe7/0x150 fs/proc/base.c:761 seq_read+0x4d2/0x1130 fs/seq_file.c:237 do_loop_readv_writev fs/read_write.c:695 [inline] do_loop_readv_writev fs/read_write.c:682 [inline] do_iter_read+0x3e3/0x5a0 fs/read_write.c:919 vfs_readv+0xd3/0x130 fs/read_write.c:981 do_preadv+0x161/0x200 fs/read_write.c:1065 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: 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.2/18622: #0: (&p->lock){+.+.}, at: [] seq_read+0xba/0x1130 fs/seq_file.c:165 stack backtrace: CPU: 0 PID: 18622 Comm: syz-executor.2 Not tainted 4.14.182-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.isra.0.cold+0x2dc/0x425 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+0x3057/0x42a0 kernel/locking/lockdep.c:3491 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xe8/0x1430 kernel/locking/mutex.c:893 lock_trace+0x3f/0xc0 fs/proc/base.c:407 proc_pid_syscall+0x81/0x1f0 fs/proc/base.c:639 proc_single_show+0xe7/0x150 fs/proc/base.c:761 seq_read+0x4d2/0x1130 fs/seq_file.c:237 do_loop_readv_writev fs/read_write.c:695 [inline] do_loop_readv_writev fs/read_write.c:682 [inline] do_iter_read+0x3e3/0x5a0 fs/read_write.c:919 vfs_readv+0xd3/0x130 fs/read_write.c:981 do_preadv+0x161/0x200 fs/read_write.c:1065 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45ca69 RSP: 002b:00007f169f3f2c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 00000000004fa700 RCX: 000000000045ca69 RDX: 000000000000037d RSI: 0000000020000500 RDI: 0000000000000003 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000862 R14: 00000000004cb47c R15: 00007f169f3f36d4 nla_parse: 5 callbacks suppressed netlink: 4 bytes leftover after parsing attributes in process `syz-executor.0'. 9pnet_virtio: no channels available for device 127.0.0.1 overlayfs: option "workdir=./file1" is useless in a non-upper mount, ignore overlayfs: at least 2 lowerdir are needed while upperdir nonexistent 9pnet_virtio: no channels available for device 127.0.0.1 overlayfs: option "workdir=./file1" is useless in a non-upper mount, ignore overlayfs: at least 2 lowerdir are needed while upperdir nonexistent audit: type=1400 audit(1591045807.619:191): avc: denied { sys_ptrace } for pid=18618 comm="syz-executor.2" capability=19 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=cap_userns permissive=1 device macsec0 entered promiscuous mode IPv6: ADDRCONF(NETDEV_UP): macsec0: link is not ready ip6gre0: Cannot use loopback or non-ethernet device as HSR slave. nbd_handle_cmd: 16 callbacks suppressed block nbd5: Attempted send on invalid socket block nbd5: Attempted send on invalid socket print_req_error: 17 callbacks suppressed print_req_error: I/O error, dev nbd5, sector 120 ip6gre0: Cannot use loopback or non-ethernet device as HSR slave. block nbd5: Attempted send on invalid socket print_req_error: I/O error, dev nbd5, sector 64 block nbd5: Attempted send on invalid socket print_req_error: I/O error, dev nbd5, sector 120 netlink: 12 bytes leftover after parsing attributes in process `syz-executor.3'. overlayfs: filesystem on './file0' not supported as upperdir netlink: 12 bytes leftover after parsing attributes in process `syz-executor.3'. block nbd4: Attempted send on invalid socket print_req_error: I/O error, dev nbd4, sector 64 block nbd4: Attempted send on invalid socket print_req_error: I/O error, dev nbd4, sector 120 ip6gre0: Cannot use loopback or non-ethernet device as HSR slave. overlayfs: unrecognized mount option "kq[*E|Ĺ:49" or missing value block nbd5: Attempted send on invalid socket block nbd4: Attempted send on invalid socket print_req_error: I/O error, dev nbd5, sector 64 print_req_error: I/O error, dev nbd4, sector 64 block nbd5: Attempted send on invalid socket block nbd4: Attempted send on invalid socket print_req_error: I/O error, dev nbd5, sector 120 print_req_error: I/O error, dev nbd4, sector 120 overlayfs: unrecognized mount option "kq[*E|Ĺ:49" or missing value audit: type=1804 audit(1591045809.959:192): pid=18871 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="open_writers" comm="syz-executor.3" name="/root/syzkaller-testdir070619204/syzkaller.vm2165/209/bus" dev="sda1" ino=16001 res=1 audit: type=1804 audit(1591045809.959:193): pid=18871 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="open_writers" comm="syz-executor.3" name="/root/syzkaller-testdir070619204/syzkaller.vm2165/209/bus" dev="sda1" ino=16001 res=1 print_req_error: I/O error, dev nbd4, sector 64 ip6gre0: Cannot use loopback or non-ethernet device as HSR slave. audit: type=1804 audit(1591045810.939:194): pid=18937 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="open_writers" comm="syz-executor.1" name="/root/syzkaller-testdir890337808/syzkaller.3hQHKW/211/bus" dev="sda1" ino=16389 res=1 audit: type=1804 audit(1591045811.049:195): pid=18947 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="open_writers" comm="syz-executor.1" name="/root/syzkaller-testdir890337808/syzkaller.3hQHKW/211/bus" dev="sda1" ino=16389 res=1 overlayfs: filesystem on './file0' not supported as upperdir device macsec0 left promiscuous mode gfs2: gfs2 mount does not exist gfs2: gfs2 mount does not exist overlayfs: upperdir is in-use by another mount, mount with '-o index=off' to override exclusive upperdir protection. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.3'. TCP: request_sock_TCP: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.3'. TCP: request_sock_TCP: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. nbd_handle_cmd: 20 callbacks suppressed block nbd4: Attempted send on invalid socket print_req_error: 19 callbacks suppressed print_req_error: I/O error, dev nbd4, sector 64 block nbd4: Attempted send on invalid socket print_req_error: I/O error, dev nbd4, sector 120 audit: type=1804 audit(1591045814.119:196): pid=19148 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="open_writers" comm="syz-executor.5" name="/root/syzkaller-testdir948800450/syzkaller.XgqNi4/368/bus" dev="sda1" ino=16105 res=1 audit: type=1804 audit(1591045814.199:197): pid=19148 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir948800450/syzkaller.XgqNi4/368/bus" dev="sda1" ino=16105 res=1 audit: type=1804 audit(1591045814.279:198): pid=19156 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir948800450/syzkaller.XgqNi4/368/bus" dev="sda1" ino=16105 res=1 audit: type=1804 audit(1591045814.339:199): pid=19148 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir948800450/syzkaller.XgqNi4/368/bus" dev="sda1" ino=16105 res=1 netlink: 12 bytes leftover after parsing attributes in process `syz-executor.3'. TCP: request_sock_TCP: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. audit: type=1804 audit(1591045814.409:200): pid=19148 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir948800450/syzkaller.XgqNi4/368/bus" dev="sda1" ino=16105 res=1 audit: type=1804 audit(1591045814.499:201): pid=19156 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir948800450/syzkaller.XgqNi4/368/bus" dev="sda1" ino=16105 res=1 block nbd4: Attempted send on invalid socket print_req_error: I/O error, dev nbd4, sector 64 block nbd4: Attempted send on invalid socket print_req_error: I/O error, dev nbd4, sector 120 netlink: 12 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.0'. block nbd4: Attempted send on invalid socket print_req_error: I/O error, dev nbd4, sector 64 block nbd4: Attempted send on invalid socket print_req_error: I/O error, dev nbd4, sector 120 netlink: 12 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.3'. kauditd_printk_skb: 4 callbacks suppressed audit: type=1804 audit(1591045815.299:206): pid=19207 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="open_writers" comm="syz-executor.5" name="/root/syzkaller-testdir948800450/syzkaller.XgqNi4/370/bus" dev="sda1" ino=15986 res=1 TCP: request_sock_TCP: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. audit: type=1804 audit(1591045815.379:207): pid=19207 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir948800450/syzkaller.XgqNi4/370/bus" dev="sda1" ino=15986 res=1 audit: type=1804 audit(1591045815.459:208): pid=19221 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir948800450/syzkaller.XgqNi4/370/bus" dev="sda1" ino=15986 res=1 audit: type=1804 audit(1591045815.789:209): pid=19239 uid=0 auid=0 ses=4 subj=system_u:system_r:kernel_t:s0 op="invalid_pcr" cause="open_writers" comm="syz-executor.5" name="/root/syzkaller-testdir948800450/syzkaller.XgqNi4/371/bus" dev="sda1" ino=16060 res=1