kauditd_printk_skb: 440 callbacks suppressed audit: type=1400 audit(1551197462.161:48015): avc: denied { map } for pid=8051 comm="modprobe" path="/bin/kmod" dev="sda1" ino=1440 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 ====================================================== WARNING: possible circular locking dependency detected 4.14.103+ #20 Not tainted ------------------------------------------------------ syz-executor.4/8056 is trying to acquire lock: (&sig->cred_guard_mutex){+.+.}, at: [] proc_pid_attr_write+0x152/0x280 fs/proc/base.c:2590 but task is already holding lock: (&pipe->mutex/1){+.+.}, at: [] pipe_lock_nested fs/pipe.c:67 [inline] (&pipe->mutex/1){+.+.}, at: [] pipe_lock+0x58/0x70 fs/pipe.c:75 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&pipe->mutex/1){+.+.}: -> #0 (&sig->cred_guard_mutex){+.+.}: other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&pipe->mutex/1); lock(&sig->cred_guard_mutex); lock(&pipe->mutex/1); lock(&sig->cred_guard_mutex); *** DEADLOCK *** 2 locks held by syz-executor.4/8056: #0: (sb_writers#7){.+.+}, at: [] file_start_write include/linux/fs.h:2726 [inline] #0: (sb_writers#7){.+.+}, at: [] do_splice fs/splice.c:1146 [inline] #0: (sb_writers#7){.+.+}, at: [] SYSC_splice fs/splice.c:1402 [inline] #0: (sb_writers#7){.+.+}, at: [] SyS_splice+0xec1/0x12d0 fs/splice.c:1382 #1: (&pipe->mutex/1){+.+.}, at: [] pipe_lock_nested fs/pipe.c:67 [inline] #1: (&pipe->mutex/1){+.+.}, at: [] pipe_lock+0x58/0x70 fs/pipe.c:75 stack backtrace: CPU: 0 PID: 8056 Comm: syz-executor.4 Not tainted 4.14.103+ #20 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xb9/0x10e lib/dump_stack.c:53 print_circular_bug.isra.0.cold+0x2dc/0x425 kernel/locking/lockdep.c:1258 audit: type=1400 audit(1551197462.211:48016): avc: denied { map } for pid=8051 comm="modprobe" path="/bin/kmod" dev="sda1" ino=1440 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(1551197462.211:48017): avc: denied { map } for pid=8051 comm="modprobe" path="/lib/x86_64-linux-gnu/ld-2.13.so" dev="sda1" ino=2668 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(1551197462.251:48018): avc: denied { bind } for pid=8044 comm="syz-executor.2" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1 audit: type=1400 audit(1551197462.261:48019): avc: denied { connect } for pid=8044 comm="syz-executor.2" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1 audit: audit_backlog=65 > audit_backlog_limit=64 audit: audit_backlog=65 > audit_backlog_limit=64 audit: audit_backlog=65 > audit_backlog_limit=64 audit: audit_backlog=65 > audit_backlog_limit=64 audit: audit_backlog=65 > audit_backlog_limit=64 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=8211 comm=syz-executor.3 kauditd_printk_skb: 584 callbacks suppressed audit: type=1400 audit(1551197467.171:48585): avc: denied { map } for pid=8231 comm="blkid" path="/lib/x86_64-linux-gnu/libblkid.so.1.1.0" dev="sda1" ino=2825 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=34152 sclass=netlink_route_socket pig=8240 comm=syz-executor.0 audit: type=1400 audit(1551197467.181:48586): avc: denied { map } for pid=8234 comm="modprobe" path="/etc/ld.so.cache" dev="sda1" ino=2503 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=34152 sclass=netlink_route_socket pig=8243 comm=syz-executor.0 audit: type=1400 audit(1551197467.181:48587): avc: denied { map } for pid=8237 comm="blkid" path="/lib/x86_64-linux-gnu/ld-2.13.so" dev="sda1" ino=2668 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(1551197467.191:48588): avc: denied { map } for pid=8237 comm="blkid" path="/lib/x86_64-linux-gnu/ld-2.13.so" dev="sda1" ino=2668 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: audit_backlog=65 > audit_backlog_limit=64 audit: audit_backlog=65 > audit_backlog_limit=64 audit: audit_backlog=65 > audit_backlog_limit=64 audit: audit_backlog=65 > audit_backlog_limit=64 audit: audit_lost=738 audit_rate_limit=0 audit_backlog_limit=64 audit: audit_lost=739 audit_rate_limit=0 audit_backlog_limit=64 SELinux: unrecognized netlink message: protocol=9 nlmsg_type=30 sclass=netlink_audit_socket pig=8259 comm=syz-executor.0 binder: BINDER_SET_CONTEXT_MGR already set binder: 8322:8339 ioctl 40046207 0 returned -16 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=48427 sclass=netlink_route_socket pig=8355 comm=syz-executor.3 kauditd_printk_skb: 701 callbacks suppressed audit: type=1400 audit(1551197472.181:49240): avc: denied { map } for pid=8402 comm="getty" path="/lib/x86_64-linux-gnu/libutil-2.13.so" dev="sda1" ino=2681 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1