====================================================== WARNING: possible circular locking dependency detected 4.14.85+ #15 Not tainted ------------------------------------------------------ : renamed from eql syz-executor0/22383 is trying to acquire lock: (&sig->cred_guard_mutex){+.+.}, at: [] do_io_accounting+0x1d7/0x770 fs/proc/base.c:2731 but task is already holding lock: (&p->lock){+.+.}, at: [] seq_read+0xd4/0x11d0 fs/seq_file.c:165 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&p->lock){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xf5/0x1480 kernel/locking/mutex.c:893 seq_read+0xd4/0x11d0 fs/seq_file.c:165 proc_reg_read+0xef/0x170 fs/proc/inode.c:217 do_loop_readv_writev fs/read_write.c:698 [inline] do_iter_read+0x3cc/0x580 fs/read_write.c:922 vfs_readv+0xe6/0x150 fs/read_write.c:984 kernel_readv fs/splice.c:361 [inline] default_file_splice_read+0x495/0x860 fs/splice.c:416 do_splice_to+0x102/0x150 fs/splice.c:880 do_splice fs/splice.c:1173 [inline] SYSC_splice fs/splice.c:1402 [inline] SyS_splice+0xf4d/0x12a0 fs/splice.c:1382 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> #1 (&pipe->mutex/1){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xf5/0x1480 kernel/locking/mutex.c:893 __pipe_lock fs/pipe.c:88 [inline] fifo_open+0x156/0x9d0 fs/pipe.c:921 do_dentry_open+0x426/0xda0 fs/open.c:764 vfs_open+0x11c/0x210 fs/open.c:878 do_last fs/namei.c:3455 [inline] path_openat+0x5f9/0x2930 fs/namei.c:3597 do_filp_open+0x197/0x270 fs/namei.c:3631 do_open_execat+0x10d/0x5b0 fs/exec.c:849 do_execveat_common.isra.14+0x6cb/0x1d60 fs/exec.c:1740 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+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> #0 (&sig->cred_guard_mutex){+.+.}: lock_acquire+0x10f/0x380 kernel/locking/lockdep.c:3991 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xf5/0x1480 kernel/locking/mutex.c:893 do_io_accounting+0x1d7/0x770 fs/proc/base.c:2731 proc_single_show+0xf1/0x160 fs/proc/base.c:762 traverse+0x32b/0x8a0 fs/seq_file.c:111 seq_read+0xc94/0x11d0 fs/seq_file.c:192 __vfs_read+0xf4/0x5b0 fs/read_write.c:411 vfs_read+0x11e/0x330 fs/read_write.c:447 SYSC_pread64 fs/read_write.c:615 [inline] SyS_pread64+0x136/0x160 fs/read_write.c:602 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 other info that might help us debug this: Chain exists of: &sig->cred_guard_mutex --> &pipe->mutex/1 --> &p->lock 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-executor0/22383: #0: (&p->lock){+.+.}, at: [] seq_read+0xd4/0x11d0 fs/seq_file.c:165 stack backtrace: CPU: 1 PID: 22383 Comm: syz-executor0 Not tainted 4.14.85+ #15 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xb9/0x11b lib/dump_stack.c:53 print_circular_bug.isra.18.cold.43+0x2d3/0x40c kernel/locking/lockdep.c:1258 check_prev_add kernel/locking/lockdep.c:1901 [inline] check_prevs_add kernel/locking/lockdep.c:2018 [inline] validate_chain kernel/locking/lockdep.c:2460 [inline] __lock_acquire+0x2ff9/0x4320 kernel/locking/lockdep.c:3487 lock_acquire+0x10f/0x380 kernel/locking/lockdep.c:3991 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xf5/0x1480 kernel/locking/mutex.c:893 do_io_accounting+0x1d7/0x770 fs/proc/base.c:2731 proc_single_show+0xf1/0x160 fs/proc/base.c:762 traverse+0x32b/0x8a0 fs/seq_file.c:111 seq_read+0xc94/0x11d0 fs/seq_file.c:192 __vfs_read+0xf4/0x5b0 fs/read_write.c:411 vfs_read+0x11e/0x330 fs/read_write.c:447 SYSC_pread64 fs/read_write.c:615 [inline] SyS_pread64+0x136/0x160 fs/read_write.c:602 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x457569 RSP: 002b:00007fb67ad1fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000011 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000040000000004 R11: 0000000000000246 R12: 00007fb67ad206d4 R13: 00000000004c37d2 R14: 00000000004d59c0 R15: 00000000ffffffff kauditd_printk_skb: 695 callbacks suppressed audit: type=1400 audit(1543958831.790:58316): avc: denied { search } for pid=22421 comm="blkid" name="/" dev="sysfs" ino=1 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:zero_device_t:s0 tclass=dir permissive=1 audit: type=1400 audit(1543958831.790:58317): avc: denied { search } for pid=190 comm="udevd" name="/" dev="sysfs" ino=1 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:zero_device_t:s0 tclass=dir permissive=1 audit: type=1400 audit(1543958831.800:58318): avc: denied { map } for pid=22435 comm="blkid" path="/sbin/blkid" dev="sda1" ino=16128 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(1543958831.800:58319): avc: denied { map } for pid=22435 comm="blkid" path="/sbin/blkid" dev="sda1" ino=16128 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(1543958831.800:58320): avc: denied { search } for pid=190 comm="udevd" name="/" dev="sysfs" ino=1 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:zero_device_t:s0 tclass=dir permissive=1 audit: type=1400 audit(1543958831.820:58321): avc: denied { map } for pid=22435 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(1543958831.830:58322): avc: denied { search } for pid=190 comm="udevd" name="/" dev="sysfs" ino=1 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:zero_device_t:s0 tclass=dir permissive=1 audit: type=1400 audit(1543958831.830:58323): avc: denied { search } for pid=22421 comm="blkid" name="/" dev="sysfs" ino=1 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:zero_device_t:s0 tclass=dir permissive=1 audit: type=1400 audit(1543958831.830:58324): avc: denied { map } for pid=22424 comm="blkid" path="/lib/x86_64-linux-gnu/libuuid.so.1.3.0" dev="sda1" ino=2819 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(1543958831.840:58325): avc: denied { search } for pid=15132 comm="udevd" name="/" dev="sysfs" ino=1 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:zero_device_t:s0 tclass=dir permissive=1 kauditd_printk_skb: 606 callbacks suppressed audit: type=1400 audit(1543958836.800:58932): avc: denied { search } for pid=19264 comm="udevd" name="/" dev="sysfs" ino=1 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:zero_device_t:s0 tclass=dir permissive=1 binder_alloc: 22577: binder_alloc_buf size 4294967328 failed, no address space binder_alloc: allocated: 0 (num: 0 largest: 0), free: 8192 (num: 1 largest: 8192) audit: type=1400 audit(1543958836.860:58933): avc: denied { map } for pid=22579 comm="blkid" 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 binder: 22577:22583 transaction failed 29201/-28, size 40-4294967281 line 3135 binder_alloc: binder_alloc_mmap_handler: 22577 20000000-20002000 already mapped failed -16 binder: BINDER_SET_CONTEXT_MGR already set binder: 22577:22580 ioctl 40046207 0 returned -16 audit: type=1400 audit(1543958836.870:58934): avc: denied { set_context_mgr } for pid=22577 comm="syz-executor0" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=binder permissive=1 binder_alloc: 22577: binder_alloc_buf, no vma binder: undelivered TRANSACTION_ERROR: 29201 binder: 22577:22595 transaction failed 29189/-3, size 40-4294967281 line 3135 audit: type=1400 audit(1543958836.870:58935): avc: denied { search } for pid=190 comm="udevd" name="/" dev="sysfs" ino=1 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:zero_device_t:s0 tclass=dir permissive=1 binder: undelivered TRANSACTION_ERROR: 29189 audit: audit_backlog=65 > audit_backlog_limit=64 audit: audit_backlog=65 > audit_backlog_limit=64 audit: audit_lost=1790 audit_rate_limit=0 audit_backlog_limit=64 audit: backlog limit exceeded audit: audit_backlog=65 > audit_backlog_limit=64 audit: audit_lost=1791 audit_rate_limit=0 audit_backlog_limit=64 netlink: 8 bytes leftover after parsing attributes in process `syz-executor4'. syz-executor4: vmalloc: allocation failure: 0 bytes, mode:0x14000c0(GFP_KERNEL), nodemask=(null) CPU: 0 PID: 22656 Comm: syz-executor4 Not tainted 4.14.85+ #15 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xb9/0x11b lib/dump_stack.c:53 warn_alloc.cold.35+0x9d/0x1b7 mm/page_alloc.c:3260 __vmalloc_node_range+0x390/0x680 mm/vmalloc.c:1776 __vmalloc_node mm/vmalloc.c:1805 [inline] __vmalloc_node_flags mm/vmalloc.c:1819 [inline] vmalloc+0x63/0x80 mm/vmalloc.c:1841 sel_write_load+0x1b5/0x1000 security/selinux/selinuxfs.c:495 __vfs_write+0xf4/0x5c0 fs/read_write.c:482 vfs_write+0x17f/0x4d0 fs/read_write.c:546 SYSC_write fs/read_write.c:593 [inline] SyS_write+0xc2/0x1a0 fs/read_write.c:585 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x457569 RSP: 002b:00007f28dbf4dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000005 RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f28dbf4e6d4 R13: 00000000004c5c5f R14: 00000000004d9e90 R15: 00000000ffffffff netlink: 8 bytes leftover after parsing attributes in process `syz-executor4'. warn_alloc_show_mem: 1 callbacks suppressed Mem-Info: active_anon:88961 inactive_anon:48655 isolated_anon:0 active_file:27571 inactive_file:14815 isolated_file:0 unevictable:0 dirty:436 writeback:13 unstable:0 slab_reclaimable:6213 slab_unreclaimable:61906 mapped:58189 shmem:2933 pagetables:3995 bounce:0 free:1324948 free_pcp:422 free_cma:0 Node 0 active_anon:355944kB inactive_anon:194620kB active_file:110284kB inactive_file:59260kB unevictable:0kB isolated(anon):0kB isolated(file):0kB mapped:232756kB dirty:1744kB writeback:52kB shmem:11732kB writeback_tmp:0kB unstable:0kB all_unreclaimable? no DMA32 free:3011412kB min:4684kB low:7692kB high:10700kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:3145324kB managed:3012140kB mlocked:0kB kernel_stack:0kB pagetables:0kB bounce:0kB free_pcp:728kB local_pcp:28kB free_cma:0kB lowmem_reserve[]: 0 3505 3505 Normal free:2288192kB min:5588kB low:9176kB high:12764kB active_anon:356044kB inactive_anon:194620kB active_file:110284kB inactive_file:59260kB unevictable:0kB writepending:1712kB present:4718592kB managed:3589236kB mlocked:0kB kernel_stack:8864kB pagetables:15980kB bounce:0kB free_pcp:952kB local_pcp:428kB free_cma:0kB lowmem_reserve[]: 0 0 0 DMA32: 5*4kB (UM) 0*8kB 2*16kB (M) 3*32kB (UM) 5*64kB (UM) 3*128kB (UM) 4*256kB (UM) 2*512kB (M) 2*1024kB (UM) 4*2048kB (UM) 732*4096kB (M) = 3011412kB Normal: 245*4kB (U) 202*8kB (U) 152*16kB (U) 324*32kB (UM) 354*64kB (UM) 257*128kB (UME) 163*256kB (UM) 139*512kB (UME) 93*1024kB (UME) 57*2048kB (UME) 462*4096kB (UM) = 2288164kB 45337 total pagecache pages 0 pages in swap cache Swap cache stats: add 0, delete 0, find 0/0 Free swap = 0kB Total swap = 0kB 1965979 pages RAM 0 pages HighMem/MovableOnly 315635 pages reserved syz-executor4: vmalloc: allocation failure: 0 bytes, mode:0x14000c0(GFP_KERNEL), nodemask=(null) CPU: 1 PID: 22676 Comm: syz-executor4 Not tainted 4.14.85+ #15 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xb9/0x11b lib/dump_stack.c:53 warn_alloc.cold.35+0x9d/0x1b7 mm/page_alloc.c:3260 __vmalloc_node_range+0x390/0x680 mm/vmalloc.c:1776 __vmalloc_node mm/vmalloc.c:1805 [inline] __vmalloc_node_flags mm/vmalloc.c:1819 [inline] vmalloc+0x63/0x80 mm/vmalloc.c:1841 sel_write_load+0x1b5/0x1000 security/selinux/selinuxfs.c:495 __vfs_write+0xf4/0x5c0 fs/read_write.c:482 vfs_write+0x17f/0x4d0 fs/read_write.c:546 SYSC_write fs/read_write.c:593 [inline] SyS_write+0xc2/0x1a0 fs/read_write.c:585 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x457569