[ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.10' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 50.585243][ T8626] [ 50.587604][ T8626] ====================================================== [ 50.594615][ T8626] WARNING: possible circular locking dependency detected [ 50.601624][ T8626] 5.14.0-rc2-syzkaller #0 Not tainted [ 50.606986][ T8626] ------------------------------------------------------ [ 50.613996][ T8626] syz-executor919/8626 is trying to acquire lock: [ 50.620404][ T8626] ffff8880141ed068 (&pipe->mutex/1){+.+.}-{3:3}, at: iter_file_splice_write+0x257/0xf30 [ 50.630171][ T8626] [ 50.630171][ T8626] but task is already holding lock: [ 50.637512][ T8626] ffff888029aac460 (sb_writers#5){.+.+}-{0:0}, at: __se_sys_splice+0x32c/0x430 [ 50.646447][ T8626] [ 50.646447][ T8626] which lock already depends on the new lock. [ 50.646447][ T8626] [ 50.656821][ T8626] [ 50.656821][ T8626] the existing dependency chain (in reverse order) is: [ 50.665808][ T8626] [ 50.665808][ T8626] -> #2 (sb_writers#5){.+.+}-{0:0}: [ 50.673164][ T8626] lock_acquire+0x182/0x4a0 [ 50.678167][ T8626] file_start_write+0xc7/0x230 [ 50.683427][ T8626] ovl_write_iter+0x81d/0xdb0 [ 50.688601][ T8626] do_iter_readv_writev+0x566/0x770 [ 50.694297][ T8626] do_iter_write+0x16c/0x5f0 [ 50.699384][ T8626] iter_file_splice_write+0x7c1/0xf30 [ 50.705249][ T8626] do_splice+0xe8e/0x17e0 [ 50.710070][ T8626] __se_sys_splice+0x32c/0x430 [ 50.715327][ T8626] do_syscall_64+0x3d/0xb0 [ 50.720250][ T8626] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 50.726641][ T8626] [ 50.726641][ T8626] -> #1 (&ovl_i_mutex_key[depth]){+.+.}-{3:3}: [ 50.734949][ T8626] lock_acquire+0x182/0x4a0 [ 50.739969][ T8626] down_write+0x97/0x170 [ 50.744710][ T8626] ovl_write_iter+0x132/0xdb0 [ 50.749883][ T8626] do_iter_readv_writev+0x566/0x770 [ 50.755596][ T8626] do_iter_write+0x16c/0x5f0 [ 50.760769][ T8626] iter_file_splice_write+0x7c1/0xf30 [ 50.766633][ T8626] do_splice+0xe8e/0x17e0 [ 50.771462][ T8626] __se_sys_splice+0x32c/0x430 [ 50.776749][ T8626] do_syscall_64+0x3d/0xb0 [ 50.781663][ T8626] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 50.788050][ T8626] [ 50.788050][ T8626] -> #0 (&pipe->mutex/1){+.+.}-{3:3}: [ 50.795594][ T8626] check_prevs_add+0x4f9/0x5b30 [ 50.800944][ T8626] __lock_acquire+0x4476/0x6100 [ 50.806475][ T8626] lock_acquire+0x182/0x4a0 [ 50.811487][ T8626] __mutex_lock_common+0x1ad/0x3770 [ 50.817180][ T8626] mutex_lock_nested+0x1a/0x20 [ 50.822441][ T8626] iter_file_splice_write+0x257/0xf30 [ 50.828310][ T8626] do_splice+0xe8e/0x17e0 [ 50.833133][ T8626] __se_sys_splice+0x32c/0x430 [ 50.838391][ T8626] do_syscall_64+0x3d/0xb0 [ 50.843310][ T8626] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 50.849696][ T8626] [ 50.849696][ T8626] other info that might help us debug this: [ 50.849696][ T8626] [ 50.859897][ T8626] Chain exists of: [ 50.859897][ T8626] &pipe->mutex/1 --> &ovl_i_mutex_key[depth] --> sb_writers#5 [ 50.859897][ T8626] [ 50.873249][ T8626] Possible unsafe locking scenario: [ 50.873249][ T8626] [ 50.880670][ T8626] CPU0 CPU1 [ 50.886016][ T8626] ---- ---- [ 50.891353][ T8626] lock(sb_writers#5); [ 50.895489][ T8626] lock(&ovl_i_mutex_key[depth]); [ 50.903092][ T8626] lock(sb_writers#5); [ 50.909746][ T8626] lock(&pipe->mutex/1); [ 50.914099][ T8626] [ 50.914099][ T8626] *** DEADLOCK *** [ 50.914099][ T8626] [ 50.922217][ T8626] 1 lock held by syz-executor919/8626: [ 50.927735][ T8626] #0: ffff888029aac460 (sb_writers#5){.+.+}-{0:0}, at: __se_sys_splice+0x32c/0x430 [ 50.937112][ T8626] [ 50.937112][ T8626] stack backtrace: [ 50.942971][ T8626] CPU: 0 PID: 8626 Comm: syz-executor919 Not tainted 5.14.0-rc2-syzkaller #0 [ 50.951703][ T8626] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.961747][ T8626] Call Trace: [ 50.965014][ T8626] dump_stack_lvl+0x1ae/0x29f [ 50.969713][ T8626] ? show_regs_print_info+0x12/0x12 [ 50.974898][ T8626] ? log_buf_vmcoreinfo_setup+0x498/0x498 [ 50.980593][ T8626] ? save_trace+0x5a/0x9f0 [ 50.984989][ T8626] print_circular_bug+0xb17/0xdc0 [ 50.989989][ T8626] ? hlock_conflict+0x1f0/0x1f0 [ 50.994811][ T8626] ? __bfs+0x369/0x700 [ 50.998867][ T8626] ? check_path+0x40/0x40 [ 51.003189][ T8626] ? noop_count+0x30/0x30 [ 51.007494][ T8626] ? save_trace+0x5a/0x9f0 [ 51.011885][ T8626] check_noncircular+0x2cc/0x390 [ 51.016798][ T8626] ? add_chain_block+0x850/0x850 [ 51.021709][ T8626] ? noop_count+0x30/0x30 [ 51.026011][ T8626] ? mark_lock+0x199/0x1eb0 [ 51.030489][ T8626] check_prevs_add+0x4f9/0x5b30 [ 51.035323][ T8626] ? check_prevs_add+0x1c41/0x5b30 [ 51.040414][ T8626] ? reacquire_held_locks+0x5f0/0x5f0 [ 51.045760][ T8626] ? mark_lock+0x199/0x1eb0 [ 51.050241][ T8626] ? __bfs+0x700/0x700 [ 51.054284][ T8626] ? reacquire_held_locks+0x5f0/0x5f0 [ 51.059641][ T8626] ? __lock_acquire+0x145b/0x6100 [ 51.064736][ T8626] ? __lock_acquire+0x145b/0x6100 [ 51.069763][ T8626] ? __lock_acquire+0x1385/0x6100 [ 51.074857][ T8626] ? mark_lock+0x199/0x1eb0 [ 51.079336][ T8626] ? __bfs+0x700/0x700 [ 51.083386][ T8626] ? trace_lock_acquire+0x190/0x190 [ 51.088571][ T8626] ? mark_lock+0x199/0x1eb0 [ 51.093049][ T8626] ? __bfs+0x700/0x700 [ 51.097095][ T8626] ? lockdep_lock+0x102/0x2c0 [ 51.101748][ T8626] ? lockdep_count_forward_deps+0x240/0x240 [ 51.107620][ T8626] __lock_acquire+0x4476/0x6100 [ 51.112445][ T8626] ? rcu_lock_release+0x5/0x20 [ 51.117190][ T8626] ? stack_trace_save+0x1e0/0x1e0 [ 51.122192][ T8626] ? rcu_read_lock_sched_held+0x87/0x110 [ 51.127805][ T8626] ? trace_lock_acquire+0x190/0x190 [ 51.132987][ T8626] ? rcu_lock_release+0x5/0x20 [ 51.137731][ T8626] ? __lock_acquire+0x6100/0x6100 [ 51.142736][ T8626] ? stack_trace_save+0x1e0/0x1e0 [ 51.147735][ T8626] ? stack_trace_save+0x1e0/0x1e0 [ 51.152734][ T8626] ? is_bpf_text_address+0x253/0x270 [ 51.157996][ T8626] ? rcu_read_lock_sched_held+0x87/0x110 [ 51.163607][ T8626] ? __bpf_trace_rcu_stall_warning+0x10/0x10 [ 51.169589][ T8626] lock_acquire+0x182/0x4a0 [ 51.174068][ T8626] ? iter_file_splice_write+0x257/0xf30 [ 51.179591][ T8626] ? read_lock_is_recursive+0x10/0x10 [ 51.184937][ T8626] ? ____kasan_kmalloc+0xdb/0xf0 [ 51.189849][ T8626] ? kmalloc_array+0x2d/0x40 [ 51.194410][ T8626] ? iter_file_splice_write+0x223/0xf30 [ 51.199930][ T8626] ? __might_sleep+0x100/0x100 [ 51.204693][ T8626] ? entry_SYSCALL_64_after_hwframe+0x44/0xae [ 51.210742][ T8626] __mutex_lock_common+0x1ad/0x3770 [ 51.215920][ T8626] ? iter_file_splice_write+0x257/0xf30 [ 51.221446][ T8626] ? kmalloc_array+0x2d/0x40 [ 51.226014][ T8626] ? iter_file_splice_write+0x257/0xf30 [ 51.231545][ T8626] ? __bpf_trace_rcu_stall_warning+0x10/0x10 [ 51.237512][ T8626] ? mutex_lock_io_nested+0x60/0x60 [ 51.242701][ T8626] ? kmalloc_array+0x2d/0x40 [ 51.247274][ T8626] ? __kmalloc+0xb4/0x390 [ 51.251591][ T8626] mutex_lock_nested+0x1a/0x20 [ 51.256335][ T8626] iter_file_splice_write+0x257/0xf30 [ 51.261696][ T8626] ? splice_from_pipe+0x200/0x200 [ 51.266704][ T8626] ? rcu_read_lock_any_held+0xb1/0x130 [ 51.272153][ T8626] ? rcu_read_lock_bh_held+0xf0/0xf0 [ 51.277425][ T8626] ? rw_verify_area+0x1b8/0x370 [ 51.282257][ T8626] ? splice_from_pipe+0x200/0x200 [ 51.287263][ T8626] do_splice+0xe8e/0x17e0 [ 51.291594][ T8626] ? __fget_files+0x35a/0x390 [ 51.296248][ T8626] ? splice_file_to_pipe+0x660/0x660 [ 51.301515][ T8626] ? __fdget+0x183/0x210 [ 51.305752][ T8626] __se_sys_splice+0x32c/0x430 [ 51.310495][ T8626] ? __x64_sys_splice+0xf0/0xf0 [ 51.315322][ T8626] ? syscall_enter_from_user_mode+0x2e/0x1b0 [ 51.321383][ T8626] ? lockdep_hardirqs_on+0x8d/0x130 [ 51.326555][ T8626] ? __x64_sys_splice+0x1d/0xf0 [ 51.331380][ T8626] do_syscall_64+0x3d/0xb0 [ 51.335777][ T8626] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 51.341651][ T8626] RIP: 0033:0x4461b9 [ 51.345536][ T8626] Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 15 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 [ 51.365119][ T8626] RSP: 002b:00007f7b06be32e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 [ 51.373519][ T8626] RAX: ffffffffffffffda RBX: 00000000004cb4f0 RCX: 00000000004461b9 executing program executing program [ 51.381500][ T8626] RDX: 0000000000000005 RSI: 0000000000000000 RDI: 0000000000000003 [ 51.389545][ T8626] RBP: 000000000049b06c R08: 000000000004ffdc R09: 0000000000000000 [ 51.397494][ T8626] R10: 0000000000000000 R11: 0000000000000246 R12: 3d72696472657070 [ 51.405442][ T8626] R13: 0079616c7265766f R14: 69662f7375622f2e R15: 00000000004cb4f8 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program