audit: type=1400 audit(1663770776.254:9): avc: denied { kernel } for pid=3936 comm="syz-executor.1" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=perf_event permissive=1 ------------[ cut here ]------------ ====================================================== WARNING: possible circular locking dependency detected 6.0.0-rc6-next-20220921 #1 Not tainted ------------------------------------------------------ syz-executor.1/3937 is trying to acquire lock: ffffffff853faab8 ((console_sem).lock){....}-{2:2}, at: down_trylock+0xe/0x70 but task is already holding lock: ffff88800d06f420 (&ctx->lock){....}-{2:2}, at: __perf_event_task_sched_out+0x53b/0x18d0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&ctx->lock){....}-{2:2}: _raw_spin_lock+0x2a/0x40 __perf_event_task_sched_out+0x53b/0x18d0 __schedule+0xedd/0x2470 schedule+0xda/0x1b0 exit_to_user_mode_prepare+0x114/0x1a0 syscall_exit_to_user_mode+0x19/0x40 do_syscall_64+0x48/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #2 (&rq->__lock){-.-.}-{2:2}: _raw_spin_lock_nested+0x30/0x40 raw_spin_rq_lock_nested+0x1e/0x30 task_fork_fair+0x63/0x4d0 sched_cgroup_fork+0x3d0/0x540 copy_process+0x4183/0x6e20 kernel_clone+0xe7/0x890 user_mode_thread+0xad/0xf0 rest_init+0x24/0x250 arch_call_rest_init+0xf/0x14 start_kernel+0x4c1/0x4e6 secondary_startup_64_no_verify+0xe0/0xeb -> #1 (&p->pi_lock){-.-.}-{2:2}: _raw_spin_lock_irqsave+0x39/0x60 try_to_wake_up+0xab/0x1930 up+0x75/0xb0 __up_console_sem+0x6e/0x80 console_unlock+0x46a/0x590 do_con_write+0xc05/0x1d50 con_write+0x21/0x40 n_tty_write+0x4d4/0xfe0 file_tty_write.constprop.0+0x49c/0x8f0 vfs_write+0x9c3/0xd90 ksys_write+0x127/0x250 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 ((console_sem).lock){....}-{2:2}: __lock_acquire+0x2a02/0x5e70 lock_acquire+0x1a2/0x530 _raw_spin_lock_irqsave+0x39/0x60 down_trylock+0xe/0x70 __down_trylock_console_sem+0x3b/0xd0 vprintk_emit+0x16b/0x560 vprintk+0x84/0xa0 _printk+0xba/0xf1 report_bug.cold+0x72/0xab handle_bug+0x3c/0x70 exc_invalid_op+0x14/0x50 asm_exc_invalid_op+0x16/0x20 group_sched_out.part.0+0x2c7/0x460 ctx_sched_out+0x8f1/0xc10 __perf_event_task_sched_out+0x6d0/0x18d0 __schedule+0xedd/0x2470 schedule+0xda/0x1b0 exit_to_user_mode_prepare+0x114/0x1a0 syscall_exit_to_user_mode+0x19/0x40 do_syscall_64+0x48/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: (console_sem).lock --> &rq->__lock --> &ctx->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ctx->lock); lock(&rq->__lock); lock(&ctx->lock); lock((console_sem).lock); *** DEADLOCK *** 2 locks held by syz-executor.1/3937: #0: ffff88806ce37d18 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x1cf/0x2470 #1: ffff88800d06f420 (&ctx->lock){....}-{2:2}, at: __perf_event_task_sched_out+0x53b/0x18d0 stack backtrace: CPU: 0 PID: 3937 Comm: syz-executor.1 Not tainted 6.0.0-rc6-next-20220921 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack_lvl+0x8b/0xb3 check_noncircular+0x263/0x2e0 __lock_acquire+0x2a02/0x5e70 lock_acquire+0x1a2/0x530 _raw_spin_lock_irqsave+0x39/0x60 down_trylock+0xe/0x70 __down_trylock_console_sem+0x3b/0xd0 vprintk_emit+0x16b/0x560 vprintk+0x84/0xa0 _printk+0xba/0xf1 report_bug.cold+0x72/0xab handle_bug+0x3c/0x70 exc_invalid_op+0x14/0x50 asm_exc_invalid_op+0x16/0x20 RIP: 0010:group_sched_out.part.0+0x2c7/0x460 Code: 5e 41 5f e9 9b b9 ef ff e8 96 b9 ef ff 65 8b 1d 2b 12 ac 7e 31 ff 89 de e8 36 b6 ef ff 85 db 0f 84 8a 00 00 00 e8 79 b9 ef ff <0f> 0b e9 a5 fe ff ff e8 6d b9 ef ff 48 8d 7d 10 48 b8 00 00 00 00 RSP: 0018:ffff8880411b7c48 EFLAGS: 00010006 RAX: 0000000040000002 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88802eec3580 RSI: ffffffff815663a7 RDI: 0000000000000005 RBP: ffff8880086685c8 R08: 0000000000000005 R09: 0000000000000001 R10: 0000000000000000 R11: ffffffff865b001b R12: ffff88800d06f400 R13: ffff88806ce3d140 R14: ffffffff8547cf80 R15: 0000000000000002 ctx_sched_out+0x8f1/0xc10 __perf_event_task_sched_out+0x6d0/0x18d0 __schedule+0xedd/0x2470 schedule+0xda/0x1b0 exit_to_user_mode_prepare+0x114/0x1a0 syscall_exit_to_user_mode+0x19/0x40 do_syscall_64+0x48/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f5898916b19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5895e8c218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007f5898a29f68 RCX: 00007f5898916b19 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f5898a29f6c RBP: 00007f5898a29f60 R08: 000000000000000e R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 00007f5898a29f6c R13: 00007ffd756033ff R14: 00007f5895e8c300 R15: 0000000000022000 WARNING: CPU: 0 PID: 3937 at kernel/events/core.c:2309 group_sched_out.part.0+0x2c7/0x460 Modules linked in: CPU: 0 PID: 3937 Comm: syz-executor.1 Not tainted 6.0.0-rc6-next-20220921 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 RIP: 0010:group_sched_out.part.0+0x2c7/0x460 Code: 5e 41 5f e9 9b b9 ef ff e8 96 b9 ef ff 65 8b 1d 2b 12 ac 7e 31 ff 89 de e8 36 b6 ef ff 85 db 0f 84 8a 00 00 00 e8 79 b9 ef ff <0f> 0b e9 a5 fe ff ff e8 6d b9 ef ff 48 8d 7d 10 48 b8 00 00 00 00 RSP: 0018:ffff8880411b7c48 EFLAGS: 00010006 RAX: 0000000040000002 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88802eec3580 RSI: ffffffff815663a7 RDI: 0000000000000005 RBP: ffff8880086685c8 R08: 0000000000000005 R09: 0000000000000001 R10: 0000000000000000 R11: ffffffff865b001b R12: ffff88800d06f400 R13: ffff88806ce3d140 R14: ffffffff8547cf80 R15: 0000000000000002 FS: 00007f5895e8c700(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6becc094a1 CR3: 00000000182aa000 CR4: 0000000000350ef0 Call Trace: ctx_sched_out+0x8f1/0xc10 __perf_event_task_sched_out+0x6d0/0x18d0 __schedule+0xedd/0x2470 schedule+0xda/0x1b0 exit_to_user_mode_prepare+0x114/0x1a0 syscall_exit_to_user_mode+0x19/0x40 do_syscall_64+0x48/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f5898916b19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5895e8c218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007f5898a29f68 RCX: 00007f5898916b19 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f5898a29f6c RBP: 00007f5898a29f60 R08: 000000000000000e R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 00007f5898a29f6c R13: 00007ffd756033ff R14: 00007f5895e8c300 R15: 0000000000022000 irq event stamp: 774 hardirqs last enabled at (773): [] exit_to_user_mode_prepare+0x109/0x1a0 hardirqs last disabled at (774): [] __schedule+0x1225/0x2470 softirqs last enabled at (528): [] __irq_exit_rcu+0x11b/0x180 softirqs last disabled at (403): [] __irq_exit_rcu+0x11b/0x180 ---[ end trace 0000000000000000 ]--- Zero length message leads to an empty skb syz-executor.5 (3941) used greatest stack depth: 24472 bytes left tmpfs: Bad value for 'nr_blocks' tmpfs: Bad value for 'nr_blocks' syz-executor.5 (3993) used greatest stack depth: 24152 bytes left hrtimer: interrupt took 18324 ns Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed Process accounting resumed ======================================================= WARNING: The mand mount option has been deprecated and and is ignored by this kernel. Remove the mand option from the mount to silence this warning. ======================================================= Process accounting resumed audit: type=1400 audit(1663770782.127:10): avc: denied { write } for pid=4241 comm="syz-executor.7" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=perf_event permissive=1 Process accounting resumed EXT4-fs (sda): re-mounted. Quota mode: none. EXT4-fs (sda): re-mounted. Quota mode: none. loop5: detected capacity change from 0 to 256 loop5: detected capacity change from 0 to 256 loop0: detected capacity change from 0 to 256 loop4: detected capacity change from 0 to 256 loop6: detected capacity change from 0 to 40 syz-executor.6: attempt to access beyond end of device loop6: rw=2049, sector=124, nr_sectors = 4 limit=40 Buffer I/O error on dev loop6, logical block 31, lost async page write loop0: detected capacity change from 0 to 256 syz-executor.6: attempt to access beyond end of device loop6: rw=2049, sector=124, nr_sectors = 4 limit=40 Buffer I/O error on dev loop6, logical block 31, lost async page write loop6: detected capacity change from 0 to 40 loop5: detected capacity change from 0 to 256 loop3: detected capacity change from 0 to 40 loop0: detected capacity change from 0 to 256 syz-executor.6: attempt to access beyond end of device loop6: rw=2049, sector=124, nr_sectors = 4 limit=40 Buffer I/O error on dev loop6, logical block 31, lost async page write loop6: detected capacity change from 0 to 40 loop4: detected capacity change from 0 to 256 syz-executor.6: attempt to access beyond end of device loop6: rw=2049, sector=124, nr_sectors = 4 limit=40 Buffer I/O error on dev loop6, logical block 31, lost async page write loop5: detected capacity change from 0 to 256