====================================================== WARNING: possible circular locking dependency detected 4.14.227-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.1/17234 is trying to acquire lock: (&p->lock){+.+.}, at: [] seq_read+0xba/0x1120 fs/seq_file.c:165 but task is already holding lock: (sb_writers#6){.+.+}, at: [] file_start_write include/linux/fs.h:2712 [inline] (sb_writers#6){.+.+}, at: [] do_sendfile+0x84f/0xb30 fs/read_write.c:1440 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (sb_writers#6){.+.+}: 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 -> #2 (&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 -> #1 (&sig->cred_guard_mutex){+.+.}: __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 -> #0 (&p->lock){+.+.}: 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 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 other info that might help us debug this: Chain exists of: &p->lock --> &ovl_i_mutex_dir_key[depth] --> sb_writers#6 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sb_writers#6); lock(&ovl_i_mutex_dir_key[depth]); lock(sb_writers#6); lock(&p->lock); *** DEADLOCK *** 1 lock held by syz-executor.1/17234: #0: (sb_writers#6){.+.+}, at: [] file_start_write include/linux/fs.h:2712 [inline] #0: (sb_writers#6){.+.+}, at: [] do_sendfile+0x84f/0xb30 fs/read_write.c:1440 stack backtrace: CPU: 0 PID: 17234 Comm: syz-executor.1 Not tainted 4.14.227-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 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 RIP: 0033:0x466459 RSP: 002b:00007fee9fb5d188 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000004 RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000 R10: 00008080fffffffe R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffc32b4d66f R14: 00007fee9fb5d300 R15: 0000000000022000 CUSE: unknown device info "" CUSE: unknown device info "* 2ՖI?" CUSE: unknown device info "&*e/4nhIJ[5M9{/d-skj/XPQ(ڡmtCohp)"_t}#(92|6\Qհe5]2Dni!8v[D`zkHu,g5_x!b 2$AOa׌z" netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. CUSE: unknown device info "V" CUSE: DEVNAME unspecified CUSE: unknown device info "" netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. CUSE: unknown device info "* 2ՖI?" CUSE: unknown device info "&*e/4nhIJ[5M9{/d-skj/XPQ(ڡmtCohp)"_t}#(92|6\Qհe5]2Dni!8v[D`zkHu,g5_x!b 2$AOa׌z" CUSE: unknown device info "V" CUSE: DEVNAME unspecified audit: type=1804 audit(1616761185.364:15763): pid=17337 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.5" name="/root/syzkaller-testdir965620803/syzkaller.lgSxbR/244/bus" dev="sda1" ino=14145 res=1 audit: type=1804 audit(1616761185.414:15764): pid=17338 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir965620803/syzkaller.lgSxbR/244/bus" dev="sda1" ino=14145 res=1 Bluetooth: hci5 command 0x0406 tx timeout netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. CUSE: unknown device info "" CUSE: unknown device info "* 2ՖI?" CUSE: unknown device info "&*e/4nhIJ[5M9{/d-skj/XPQ(ڡmtCohp)"_t}#(92|6\Qհe5]2Dni!8v[D`zkHu,g5_x!b 2$AOa׌z" CUSE: unknown device info "V" CUSE: DEVNAME unspecified CUSE: unknown device info "" CUSE: unknown device info "* 2ՖI?" CUSE: unknown device info "&*e/4nhIJ[5M9{/d-skj/XPQ(ڡmtCohp)"_t}#(92|6\Qհe5]2Dni!8v[D`zkHu,g5_x!b 2$AOa׌z" CUSE: unknown device info "V" CUSE: DEVNAME unspecified netlink: 24 bytes leftover after parsing attributes in process `syz-executor.4'. CUSE: unknown device info "" CUSE: unknown device info "* 2ՖI?" CUSE: unknown device info "&*e/4nhIJ[5M9{/d-skj/XPQ(ڡmtCohp)"_t}#(92|6\Qհe5]2Dni!8v[D`zkHu,g5_x!b 2$AOa׌z" CUSE: unknown device info "V" CUSE: DEVNAME unspecified audit: type=1804 audit(1616761186.284:15765): pid=17400 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.5" name="/root/syzkaller-testdir965620803/syzkaller.lgSxbR/245/bus" dev="sda1" ino=14193 res=1 audit: type=1804 audit(1616761186.364:15766): pid=17404 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir965620803/syzkaller.lgSxbR/245/bus" dev="sda1" ino=14193 res=1 CUSE: unknown device info "" CUSE: unknown device info "* 2ՖI?" CUSE: unknown device info "&*e/4nhIJ[5M9{/d-skj/XPQ(ڡmtCohp)"_t}#(92|6\Qհe5]2Dni!8v[D`zkHu,g5_x!b 2$AOa׌z" CUSE: unknown device info "V" CUSE: DEVNAME unspecified CUSE: unknown device info "" CUSE: unknown device info "* 2ՖI?" CUSE: unknown device info "&*e/4nhIJ[5M9{/d-skj/XPQ(ڡmtCohp)"_t}#(92|6\Qհe5]2Dni!8v[D`zkHu,g5_x!b 2$AOa׌z" audit: type=1804 audit(1616761186.714:15767): pid=17430 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.3" name="/root/syzkaller-testdir567304045/syzkaller.IUzABX/250/bus" dev="sda1" ino=14742 res=1 audit: type=1804 audit(1616761186.794:15768): pid=17435 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.3" name="/root/syzkaller-testdir567304045/syzkaller.IUzABX/250/bus" dev="sda1" ino=14742 res=1 CUSE: unknown device info "V" CUSE: DEVNAME unspecified audit: type=1804 audit(1616761187.154:15769): pid=17457 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.5" name="/root/syzkaller-testdir965620803/syzkaller.lgSxbR/246/bus" dev="sda1" ino=14145 res=1 audit: type=1804 audit(1616761187.234:15770): pid=17458 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.5" name="/root/syzkaller-testdir965620803/syzkaller.lgSxbR/246/bus" dev="sda1" ino=14145 res=1 audit: type=1804 audit(1616761187.574:15771): pid=17465 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="open_writers" comm="syz-executor.3" name="/root/syzkaller-testdir567304045/syzkaller.IUzABX/251/bus" dev="sda1" ino=14276 res=1 audit: type=1804 audit(1616761187.624:15772): pid=17466 uid=0 auid=4294967295 ses=4294967295 op="invalid_pcr" cause="ToMToU" comm="syz-executor.3" name="/root/syzkaller-testdir567304045/syzkaller.IUzABX/251/bus" dev="sda1" ino=14276 res=1 JFS: r is an invalid error handler netlink: 44 bytes leftover after parsing attributes in process `syz-executor.4'. JFS: r is an invalid error handler netlink: 44 bytes leftover after parsing attributes in process `syz-executor.4'. overlayfs: unrecognized mount option "appraise" or missing value REISERFS (device loop0): found reiserfs format "3.6" with non-standard journal REISERFS (device loop0): using ordered data mode netlink: 44 bytes leftover after parsing attributes in process `syz-executor.4'. overlayfs: unrecognized mount option "appraise" or missing value reiserfs: using flush barriers REISERFS (device loop0): journal params: device loop0, size 8192, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30 netlink: 44 bytes leftover after parsing attributes in process `syz-executor.4'. REISERFS (device loop0): checking transaction log (loop0) netlink: 12 bytes leftover after parsing attributes in process `syz-executor.4'. REISERFS (device loop0): Using rupasov hash to sort names REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.4'. FAT-fs (loop5): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop5): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) netlink: 12 bytes leftover after parsing attributes in process `syz-executor.4'. netlink: 12 bytes leftover after parsing attributes in process `syz-executor.4'. FAT-fs (loop5): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop5): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) REISERFS (device loop0): found reiserfs format "3.6" with non-standard journal REISERFS (device loop0): using ordered data mode reiserfs: using flush barriers REISERFS (device loop0): journal params: device loop0, size 8192, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30 REISERFS (device loop0): checking transaction log (loop0) REISERFS (device loop0): Using rupasov hash to sort names REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage. FAT-fs (loop5): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop5): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop5): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) FAT-fs (loop5): Invalid FSINFO signature: 0x00000000, 0x00000000 (sector = 1) REISERFS (device loop0): found reiserfs format "3.6" with non-standard journal REISERFS (device loop0): using ordered data mode reiserfs: using flush barriers REISERFS (device loop0): journal params: device loop0, size 8192, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30 REISERFS (device loop0): checking transaction log (loop0) REISERFS (device loop0): Using rupasov hash to sort names REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage. vhci_hcd: USB_PORT_FEAT_LINK_STATE req not supported for USB 2.0 roothub bridge0: port 2(bridge_slave_1) entered disabled state bridge0: port 1(bridge_slave_0) entered disabled state vhci_hcd: USB_PORT_FEAT_LINK_STATE req not supported for USB 2.0 roothub vhci_hcd: USB_PORT_FEAT_LINK_STATE req not supported for USB 2.0 roothub vhci_hcd: USB_PORT_FEAT_LINK_STATE req not supported for USB 2.0 roothub batman_adv: batadv0: Interface deactivated: batadv_slave_0 batman_adv: batadv0: Interface deactivated: batadv_slave_1 REISERFS (device loop0): found reiserfs format "3.6" with non-standard journal REISERFS (device loop0): using ordered data mode reiserfs: using flush barriers REISERFS (device loop0): journal params: device loop0, size 8192, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30 REISERFS (device loop0): checking transaction log (loop0) IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready IPv6: ADDRCONF(NETDEV_CHANGE): vcan0: link becomes ready 8021q: adding VLAN 0 to HW filter on device bond0 IPv6: ADDRCONF(NETDEV_UP): team0: link is not ready 8021q: adding VLAN 0 to HW filter on device team0 chnl_net:chnl_net_open(): err: Unable to register and open device, Err:-19 caif:caif_disconnect_client(): nothing to disconnect chnl_net:chnl_flowctrl_cb(): NET flowctrl func called flow: CLOSE/DEINIT chnl_net:chnl_net_open(): state disconnected A link change request failed with some changes committed already. Interface caif0 may have been left with an inconsistent configuration, please check. REISERFS (device loop0): Using rupasov hash to sort names REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage.