audit: type=1401 audit(1574728322.152:503): op=setxattr invalid_context=73797374656D5F753A6F626A6563745F723A7661725F73706F6F6C5F743A73303A000039D587DB272011B2708A5FCCC3864E1865A3134B2431970C3FBA39C805AD1CF34A5C27FCF60F1A
audit: type=1401 audit(1574728322.162:504): op=setxattr invalid_context=73797374656D5F753A6F626A6563745F723A7661725F73706F6F6C5F743A73303A000039D587DB272011B2708A5FCCC3864E1865A3134B2431970C3FBA39C805AD1CF34A5C27FCF60F1A
======================================================
[ INFO: possible circular locking dependency detected ]
4.9.141+ #1 Not tainted
-------------------------------------------------------
syz-executor.0/21400 is trying to acquire lock:
(&sig->cred_guard_mutex){+.+.+.}, at: [<ffffffff8166030b>] do_io_accounting+0x1fb/0x7e0 fs/proc/base.c:2690
but task is already holding lock:
(&p->lock){+.+.+.}, at: [<ffffffff8158080d>] seq_read+0xdd/0x12d0 fs/seq_file.c:178
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756
__mutex_lock_common kernel/locking/mutex.c:521 [inline]
mutex_lock_nested+0xc0/0x900 kernel/locking/mutex.c:621
seq_read+0xdd/0x12d0 fs/seq_file.c:178
proc_reg_read+0xfd/0x180 fs/proc/inode.c:203
do_loop_readv_writev.part.1+0xd5/0x280 fs/read_write.c:718
do_loop_readv_writev fs/read_write.c:707 [inline]
do_readv_writev+0x56e/0x7b0 fs/read_write.c:873
vfs_readv+0x84/0xc0 fs/read_write.c:897
kernel_readv fs/splice.c:363 [inline]
default_file_splice_read+0x451/0x7f0 fs/splice.c:435
do_splice_to+0x10c/0x170 fs/splice.c:899
do_splice fs/splice.c:1192 [inline]
SYSC_splice fs/splice.c:1416 [inline]
SyS_splice+0x10d2/0x14d0 fs/splice.c:1399
do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
entry_SYSCALL_64_after_swapgs+0x5d/0xdb
lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756
__mutex_lock_common kernel/locking/mutex.c:521 [inline]
mutex_lock_nested+0xc0/0x900 kernel/locking/mutex.c:621
__pipe_lock fs/pipe.c:87 [inline]
fifo_open+0x15c/0x9e0 fs/pipe.c:921
do_dentry_open+0x3ef/0xc90 fs/open.c:766
vfs_open+0x11c/0x210 fs/open.c:879
do_last fs/namei.c:3410 [inline]
path_openat+0x542/0x2790 fs/namei.c:3534
do_filp_open+0x197/0x270 fs/namei.c:3568
do_open_execat+0x10f/0x640 fs/exec.c:844
do_execveat_common.isra.14+0x687/0x1ed0 fs/exec.c:1723
do_execve fs/exec.c:1829 [inline]
SYSC_execve fs/exec.c:1910 [inline]
SyS_execve+0x42/0x50 fs/exec.c:1905
do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
entry_SYSCALL_64_after_swapgs+0x5d/0xdb
check_prev_add kernel/locking/lockdep.c:1828 [inline]
check_prevs_add kernel/locking/lockdep.c:1938 [inline]
validate_chain kernel/locking/lockdep.c:2265 [inline]
__lock_acquire+0x3189/0x4a10 kernel/locking/lockdep.c:3345
lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756
__mutex_lock_common kernel/locking/mutex.c:521 [inline]
mutex_lock_killable_nested+0xcc/0x9f0 kernel/locking/mutex.c:641
do_io_accounting+0x1fb/0x7e0 fs/proc/base.c:2690
proc_tgid_io_accounting+0x22/0x30 fs/proc/base.c:2739
proc_single_show+0xfd/0x170 fs/proc/base.c:785
seq_read+0x4b6/0x12d0 fs/seq_file.c:240
do_loop_readv_writev.part.1+0xd5/0x280 fs/read_write.c:718
do_loop_readv_writev fs/read_write.c:707 [inline]
do_readv_writev+0x56e/0x7b0 fs/read_write.c:873
vfs_readv+0x84/0xc0 fs/read_write.c:897
do_preadv+0x197/0x240 fs/read_write.c:974
SYSC_preadv fs/read_write.c:1024 [inline]
SyS_preadv+0x30/0x40 fs/read_write.c:1019
do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
entry_SYSCALL_64_after_swapgs+0x5d/0xdb
other info that might help us debug this:
Chain exists of:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&p->lock);
lock(&pipe->mutex/1);
lock(&p->lock);
lock(&sig->cred_guard_mutex);
*** DEADLOCK ***
1 lock held by syz-executor.0/21400:
#0: (&p->lock){+.+.+.}, at: [<ffffffff8158080d>] seq_read+0xdd/0x12d0 fs/seq_file.c:178
stack backtrace:
CPU: 0 PID: 21400 Comm: syz-executor.0 Not tainted 4.9.141+ #1
ffff8800ba787528 ffffffff81b42e79 ffffffff83caa290 ffffffff83ca4fe0
ffffffff83ca2fd0 ffff88012d65d010 ffff88012d65c740 ffff8800ba787570
ffffffff813fee40 0000000000000001 000000002d65cff0 0000000000000001
Call Trace:
[<ffffffff81b42e79>] __dump_stack lib/dump_stack.c:15 [inline]
[<ffffffff81b42e79>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
[<ffffffff813fee40>] print_circular_bug.cold.36+0x2f7/0x432 kernel/locking/lockdep.c:1202
[<ffffffff8120a539>] check_prev_add kernel/locking/lockdep.c:1828 [inline]
[<ffffffff8120a539>] check_prevs_add kernel/locking/lockdep.c:1938 [inline]
[<ffffffff8120a539>] validate_chain kernel/locking/lockdep.c:2265 [inline]
[<ffffffff8120a539>] __lock_acquire+0x3189/0x4a10 kernel/locking/lockdep.c:3345
[<ffffffff8120c8d0>] lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756
[<ffffffff8280c45c>] __mutex_lock_common kernel/locking/mutex.c:521 [inline]
[<ffffffff8280c45c>] mutex_lock_killable_nested+0xcc/0x9f0 kernel/locking/mutex.c:641
[<ffffffff8166030b>] do_io_accounting+0x1fb/0x7e0 fs/proc/base.c:2690
[<ffffffff81660912>] proc_tgid_io_accounting+0x22/0x30 fs/proc/base.c:2739
[<ffffffff8165e66d>] proc_single_show+0xfd/0x170 fs/proc/base.c:785
[<ffffffff81580be6>] seq_read+0x4b6/0x12d0 fs/seq_file.c:240
[<ffffffff81509df5>] do_loop_readv_writev.part.1+0xd5/0x280 fs/read_write.c:718
[<ffffffff8150b49e>] do_loop_readv_writev fs/read_write.c:707 [inline]
[<ffffffff8150b49e>] do_readv_writev+0x56e/0x7b0 fs/read_write.c:873
[<ffffffff8150b764>] vfs_readv+0x84/0xc0 fs/read_write.c:897
[<ffffffff8150bb97>] do_preadv+0x197/0x240 fs/read_write.c:974
[<ffffffff8150f150>] SYSC_preadv fs/read_write.c:1024 [inline]
[<ffffffff8150f150>] SyS_preadv+0x30/0x40 fs/read_write.c:1019
[<ffffffff810056ef>] do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
[<ffffffff82817893>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready
netlink: 27 bytes leftover after parsing attributes in process `syz-executor.2'.
qtaguid: iface_stat: create6(lo): no inet dev
netlink: 27 bytes leftover after parsing attributes in process `syz-executor.2'.
netlink: 27 bytes leftover after parsing attributes in process `syz-executor.2'.
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
netlink: 27 bytes leftover after parsing attributes in process `syz-executor.2'.
netlink: 27 bytes leftover after parsing attributes in process `syz-executor.2'.
IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready
qtaguid: iface_stat: create6(lo): no inet dev
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready
netlink: 27 bytes leftover after parsing attributes in process `syz-executor.2'.
netlink: 27 bytes leftover after parsing attributes in process `syz-executor.2'.
qtaguid: iface_stat: create6(lo): no inet dev
IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): ip_vti0: link becomes ready
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
IPv6: ADDRCONF(NETDEV_CHANGE): vti27: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vti28: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vti29: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vti30: link becomes ready
device sit74 left promiscuous mode
IPv6: ADDRCONF(NETDEV_CHANGE): sit74: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): sit74: link becomes ready
device sit75 left promiscuous mode
IPv6: ADDRCONF(NETDEV_CHANGE): sit75: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): sit75: link becomes ready
device sit76 left promiscuous mode
IPv6: ADDRCONF(NETDEV_CHANGE): sit76: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): sit76: link becomes ready
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready
qtaguid: iface_stat: create6(lo): no inet dev
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): ip_vti0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vti27: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vti28: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vti29: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vti30: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): sit74: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): sit75: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): sit76: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready
qtaguid: iface_stat: create6(lo): no inet dev
IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
IPv6: ADDRCONF(NETDEV_CHANGE): ip_vti0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vti27: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vti28: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vti29: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): vti30: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): sit74: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): sit75: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): sit76: link becomes ready
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21613 comm=syz-executor.5
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21649 comm=syz-executor.5
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21664 comm=syz-executor.5
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21668 comm=syz-executor.1
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21669 comm=syz-executor.2
selinux_nlmsg_perm: 1 callbacks suppressed
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21704 comm=syz-executor.5
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21705 comm=syz-executor.0
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21712 comm=syz-executor.3
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21731 comm=syz-executor.2
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21734 comm=syz-executor.1
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21735 comm=syz-executor.4
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21750 comm=syz-executor.4
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21756 comm=syz-executor.3
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21762 comm=syz-executor.0
SELinux: unrecognized netlink message: protocol=0 nlmsg_type=12152 sclass=netlink_route_socket pig=21769 comm=syz-executor.5