====================================================== WARNING: possible circular locking dependency detected 4.14.229-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.5/3489 is trying to acquire lock: (&sig->cred_guard_mutex){+.+.}, at: [] lock_trace fs/proc/base.c:407 [inline] (&sig->cred_guard_mutex){+.+.}, at: [] proc_pid_syscall+0xa7/0x2a0 fs/proc/base.c:639 but task is already holding lock: (&p->lock){+.+.}, at: [] seq_read+0xba/0x1120 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+0xc4/0x1310 kernel/locking/mutex.c:893 seq_read+0xba/0x1120 fs/seq_file.c:165 proc_reg_read+0xee/0x1a0 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+0x3eb/0x5b0 fs/read_write.c:919 vfs_readv+0xc8/0x120 fs/read_write.c:981 kernel_readv fs/splice.c:361 [inline] default_file_splice_read+0x418/0x910 fs/splice.c:416 do_splice_to+0xfb/0x140 fs/splice.c:880 splice_direct_to_actor+0x207/0x730 fs/splice.c:952 do_splice_direct+0x164/0x210 fs/splice.c:1061 do_sendfile+0x47f/0xb30 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+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 -> #1 (&ovl_i_mutex_dir_key[depth]){++++}: down_read+0x36/0x80 kernel/locking/rwsem.c:24 inode_lock_shared include/linux/fs.h:729 [inline] do_last fs/namei.c:3333 [inline] path_openat+0x149b/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_open_execat+0xd3/0x450 fs/exec.c:849 do_execveat_common+0x711/0x1f30 fs/exec.c:1755 do_execve fs/exec.c:1860 [inline] SYSC_execve fs/exec.c:1941 [inline] SyS_execve+0x3b/0x50 fs/exec.c:1936 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+0xc4/0x1310 kernel/locking/mutex.c:893 lock_trace fs/proc/base.c:407 [inline] proc_pid_syscall+0xa7/0x2a0 fs/proc/base.c:639 proc_single_show+0xe7/0x150 fs/proc/base.c:761 seq_read+0x4cf/0x1120 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+0x3eb/0x5b0 fs/read_write.c:919 vfs_readv+0xc8/0x120 fs/read_write.c:981 do_preadv fs/read_write.c:1065 [inline] SYSC_preadv fs/read_write.c:1115 [inline] SyS_preadv+0x15a/0x200 fs/read_write.c:1110 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.5/3489: #0: (&p->lock){+.+.}, at: [] seq_read+0xba/0x1120 fs/seq_file.c:165 stack backtrace: CPU: 0 PID: 3489 Comm: syz-executor.5 Not tainted 4.14.229-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+0x1b2/0x281 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 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xc4/0x1310 kernel/locking/mutex.c:893 lock_trace fs/proc/base.c:407 [inline] proc_pid_syscall+0xa7/0x2a0 fs/proc/base.c:639 proc_single_show+0xe7/0x150 fs/proc/base.c:761 seq_read+0x4cf/0x1120 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+0x3eb/0x5b0 fs/read_write.c:919 vfs_readv+0xc8/0x120 fs/read_write.c:981 do_preadv fs/read_write.c:1065 [inline] SYSC_preadv fs/read_write.c:1115 [inline] SyS_preadv+0x15a/0x200 fs/read_write.c:1110 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x466459 RSP: 002b:00007fcbbf8a8188 EFLAGS: 00000246 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 00000000000001a1 RSI: 00000000200017c0 RDI: 0000000000000004 RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffc4ee36f9f R14: 00007fcbbf8a8300 R15: 0000000000022000 netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. Bluetooth: hci0 command 0x040f tx timeout Dev loop5: unable to read RDB block 1 loop5: unable to read partition table loop5: partition table beyond EOD, truncated loop_reread_partitions: partition scan of loop5 () failed (rc=-5) MTD: Attempt to mount non-MTD device "/dev/loop4" romfs: VFS: Can't find a romfs filesystem on dev loop4. Dev loop5: unable to read RDB block 8 loop5: unable to read partition table loop5: partition table beyond EOD, truncated loop_reread_partitions: partition scan of loop5 () failed (rc=-5) Dev loop5: unable to read RDB block 8 loop5: unable to read partition table netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. loop5: partition table beyond EOD, truncated netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. loop_reread_partitions: partition scan of loop5 () failed (rc=-5) print_req_error: I/O error, dev loop5, sector 0 Buffer I/O error on dev loop5, logical block 0, async page read ldm_validate_partition_table(): Disk read failed. Dev loop5: unable to read RDB block 0 loop5: unable to read partition table loop5: partition table beyond EOD, truncated Dev loop5: unable to read RDB block 1 loop5: unable to read partition table loop5: partition table beyond EOD, truncated loop_reread_partitions: partition scan of loop5 () failed (rc=-5) Dev loop5: unable to read RDB block 8 loop5: unable to read partition table loop5: partition table beyond EOD, truncated loop_reread_partitions: partition scan of loop5 () failed (rc=-5) Bluetooth: hci0 command 0x0419 tx timeout netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.2'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.3'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.3'. FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 0 PID: 4423 Comm: syz-executor.0 Not tainted 4.14.229-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+0x1b2/0x281 lib/dump_stack.c:58 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0x10a/0x149 lib/fault-inject.c:149 should_failslab+0xd6/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] kmem_cache_alloc+0x28e/0x3c0 mm/slab.c:3550 getname_flags+0xc8/0x550 fs/namei.c:138 do_sys_open+0x1ce/0x410 fs/open.c:1075 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x466459 RSP: 002b:00007fe7fbc7b188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007fe7fbc7b1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fff5f98d03f R14: 00007fe7fbc7b300 R15: 0000000000022000 FAULT_INJECTION: forcing a failure. name fail_page_alloc, interval 1, probability 0, space 0, times 0 CPU: 0 PID: 4440 Comm: syz-executor.0 Not tainted 4.14.229-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+0x1b2/0x281 lib/dump_stack.c:58 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0x10a/0x149 lib/fault-inject.c:149 should_fail_alloc_page mm/page_alloc.c:2898 [inline] prepare_alloc_pages mm/page_alloc.c:4131 [inline] __alloc_pages_nodemask+0x22c/0x2720 mm/page_alloc.c:4179 __alloc_pages include/linux/gfp.h:484 [inline] __alloc_pages_node include/linux/gfp.h:497 [inline] kmem_getpages mm/slab.c:1419 [inline] cache_grow_begin+0x91/0x700 mm/slab.c:2676 cache_alloc_refill+0x273/0x350 mm/slab.c:3043 ____cache_alloc mm/slab.c:3125 [inline] __do_cache_alloc mm/slab.c:3347 [inline] slab_alloc mm/slab.c:3382 [inline] kmem_cache_alloc+0x333/0x3c0 mm/slab.c:3550 getname_flags+0xc8/0x550 fs/namei.c:138 do_sys_open+0x1ce/0x410 fs/open.c:1075 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x466459 RSP: 002b:00007fe7fbc7b188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007fe7fbc7b1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fff5f98d03f R14: 00007fe7fbc7b300 R15: 0000000000022000 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 PID: 4495 Comm: syz-executor.0 Not tainted 4.14.229-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+0x1b2/0x281 lib/dump_stack.c:58 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0x10a/0x149 lib/fault-inject.c:149 should_failslab+0xd6/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] kmem_cache_alloc+0x28e/0x3c0 mm/slab.c:3550 kmem_cache_zalloc include/linux/slab.h:651 [inline] get_empty_filp+0x86/0x3e0 fs/file_table.c:123 path_openat+0x84/0x2970 fs/namei.c:3545 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: 0033:0x466459 RSP: 002b:00007fe7fbc7b188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007fe7fbc7b1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fff5f98d03f R14: 00007fe7fbc7b300 R15: 0000000000022000 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 PID: 4515 Comm: syz-executor.0 Not tainted 4.14.229-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+0x1b2/0x281 lib/dump_stack.c:58 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0x10a/0x149 lib/fault-inject.c:149 should_failslab+0xd6/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] kmem_cache_alloc_trace+0x29a/0x3d0 mm/slab.c:3616 kmalloc include/linux/slab.h:488 [inline] kzalloc include/linux/slab.h:661 [inline] aa_alloc_file_ctx security/apparmor/include/file.h:60 [inline] apparmor_file_alloc_security+0x129/0x800 security/apparmor/lsm.c:431 security_file_alloc+0x66/0xa0 security/security.c:874 get_empty_filp+0x15c/0x3e0 fs/file_table.c:129 path_openat+0x84/0x2970 fs/namei.c:3545 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: 0033:0x466459 RSP: 002b:00007fe7fbc7b188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007fe7fbc7b1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fff5f98d03f R14: 00007fe7fbc7b300 R15: 0000000000022000 FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. CPU: 0 PID: 4552 Comm: syz-executor.0 Not tainted 4.14.229-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+0x1b2/0x281 lib/dump_stack.c:58 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0x10a/0x149 lib/fault-inject.c:149 should_failslab+0xd6/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] kmem_cache_alloc_trace+0x29a/0x3d0 mm/slab.c:3616 kmalloc include/linux/slab.h:488 [inline] kzalloc include/linux/slab.h:661 [inline] simple_attr_open+0x53/0x1d0 fs/libfs.c:805 full_proxy_open+0x3ff/0x720 fs/debugfs/file.c:260 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 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: 0033:0x466459 RSP: 002b:00007fe7fbc7b188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007fe7fbc7b1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fff5f98d03f R14: 00007fe7fbc7b300 R15: 0000000000022000 netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. FAULT_INJECTION: forcing a failure. name failslab, interval 1, probability 0, space 0, times 0 CPU: 1 PID: 4608 Comm: syz-executor.0 Not tainted 4.14.229-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+0x1b2/0x281 lib/dump_stack.c:58 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold+0x10a/0x149 lib/fault-inject.c:149 should_failslab+0xd6/0x130 mm/failslab.c:32 slab_pre_alloc_hook mm/slab.h:421 [inline] slab_alloc mm/slab.c:3376 [inline] kmem_cache_alloc_trace+0x29a/0x3d0 mm/slab.c:3616 kmalloc include/linux/slab.h:488 [inline] kzalloc include/linux/slab.h:661 [inline] simple_attr_open+0x53/0x1d0 fs/libfs.c:805 full_proxy_open+0x3ff/0x720 fs/debugfs/file.c:260 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 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: 0033:0x466459 RSP: 002b:00007fe7fbc7b188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000002 RSI: 0000000020000080 RDI: ffffffffffffff9c RBP: 00007fe7fbc7b1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fff5f98d03f R14: 00007fe7fbc7b300 R15: 0000000000022000 netlink: 24 bytes leftover after parsing attributes in process `syz-executor.0'.