====================================================== WARNING: possible circular locking dependency detected 6.9.0-rc7-syzkaller-00023-g6d7ddd805123 #0 Not tainted ------------------------------------------------------ syz-executor.1/24286 is trying to acquire lock: ffff888025541290 (&psock->link_lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888025541290 (&psock->link_lock){+...}-{2:2}, at: sock_map_add_link net/core/sock_map.c:134 [inline] ffff888025541290 (&psock->link_lock){+...}-{2:2}, at: sock_hash_update_common+0x422/0xa60 net/core/sock_map.c:1029 but task is already holding lock: ffff888046786e68 (&htab->buckets[i].lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888046786e68 (&htab->buckets[i].lock){+.-.}-{2:2}, at: sock_hash_update_common+0x1fe/0xa60 net/core/sock_map.c:1013 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&htab->buckets[i].lock){+.-.}-{2:2}: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] sock_hash_delete_elem+0xeb/0x290 net/core/sock_map.c:945 ___bpf_prog_run+0x3e51/0xabd0 kernel/bpf/core.c:1997 __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2236 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline] __bpf_prog_run include/linux/filter.h:657 [inline] bpf_prog_run include/linux/filter.h:664 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline] bpf_trace_run2+0x151/0x420 kernel/trace/bpf_trace.c:2420 trace_kfree include/trace/events/kmem.h:94 [inline] kfree+0x225/0x3a0 mm/slub.c:4383 sk_psock_free_link include/linux/skmsg.h:421 [inline] sock_map_del_link net/core/sock_map.c:158 [inline] sock_map_unref+0x392/0x6e0 net/core/sock_map.c:180 __sock_map_delete+0x88/0xe0 net/core/sock_map.c:423 sock_map_delete_elem+0xb5/0x100 net/core/sock_map.c:449 ___bpf_prog_run+0x3e51/0xabd0 kernel/bpf/core.c:1997 __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2236 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline] __bpf_prog_run include/linux/filter.h:657 [inline] bpf_prog_run include/linux/filter.h:664 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline] bpf_trace_run1+0x149/0x410 kernel/trace/bpf_trace.c:2419 __bpf_trace_scsi_dispatch_cmd_start+0x98/0xd0 include/trace/events/scsi.h:156 trace_scsi_dispatch_cmd_start include/trace/events/scsi.h:156 [inline] scsi_dispatch_cmd drivers/scsi/scsi_lib.c:1608 [inline] scsi_queue_rq+0x26d5/0x36a0 drivers/scsi/scsi_lib.c:1851 blk_mq_dispatch_rq_list+0x452/0x2030 block/blk-mq.c:2053 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:170 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline] __blk_mq_sched_dispatch_requests+0xcdf/0x1620 block/blk-mq-sched.c:309 blk_mq_sched_dispatch_requests+0xd4/0x150 block/blk-mq-sched.c:331 blk_mq_run_hw_queue+0x645/0x9a0 block/blk-mq.c:2268 blk_mq_dispatch_plug_list block/blk-mq.c:2769 [inline] blk_mq_flush_plug_list.part.0+0x611/0x1d90 block/blk-mq.c:2817 blk_mq_flush_plug_list+0x62/0x80 block/blk-mq.c:2787 __blk_flush_plug+0x2c5/0x4b0 block/blk-core.c:1190 blk_finish_plug block/blk-core.c:1217 [inline] blk_finish_plug+0x53/0xa0 block/blk-core.c:1214 ext4_do_writepages+0x1f9a/0x3250 fs/ext4/inode.c:2730 ext4_writepages+0x303/0x730 fs/ext4/inode.c:2768 do_writepages+0x1a3/0x7f0 mm/page-writeback.c:2612 filemap_fdatawrite_wbc mm/filemap.c:397 [inline] filemap_fdatawrite_wbc+0x148/0x1c0 mm/filemap.c:387 __filemap_fdatawrite_range+0xba/0x100 mm/filemap.c:430 file_write_and_wait_range+0xd0/0x140 mm/filemap.c:788 ext4_sync_file+0x296/0xf30 fs/ext4/fsync.c:158 vfs_fsync_range+0x141/0x230 fs/sync.c:188 generic_write_sync include/linux/fs.h:2795 [inline] ext4_buffered_write_iter+0x2e6/0x3d0 fs/ext4/file.c:305 ext4_file_write_iter+0x874/0x1a40 fs/ext4/file.c:698 call_write_iter include/linux/fs.h:2110 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0x6db/0x1100 fs/read_write.c:590 ksys_write+0x12f/0x260 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&psock->link_lock){+...}-{2:2}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] sock_map_add_link net/core/sock_map.c:134 [inline] sock_hash_update_common+0x422/0xa60 net/core/sock_map.c:1029 sock_map_update_elem_sys+0x280/0x570 net/core/sock_map.c:584 bpf_map_update_value+0x36c/0x6c0 kernel/bpf/syscall.c:172 map_update_elem+0x623/0x910 kernel/bpf/syscall.c:1641 __sys_bpf+0xab9/0x4b40 kernel/bpf/syscall.c:5648 __do_sys_bpf kernel/bpf/syscall.c:5767 [inline] __se_sys_bpf kernel/bpf/syscall.c:5765 [inline] __x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:5765 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&htab->buckets[i].lock); lock(&psock->link_lock); lock(&htab->buckets[i].lock); lock(&psock->link_lock); *** DEADLOCK *** 3 locks held by syz-executor.1/24286: #0: ffff88801ebdd258 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1673 [inline] #0: ffff88801ebdd258 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sock_map_sk_acquire net/core/sock_map.c:117 [inline] #0: ffff88801ebdd258 (sk_lock-AF_UNIX){+.+.}-{0:0}, at: sock_map_update_elem_sys+0x1b6/0x570 net/core/sock_map.c:578 #1: ffffffff8d7b0e20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #1: ffffffff8d7b0e20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #1: ffffffff8d7b0e20 (rcu_read_lock){....}-{1:2}, at: sock_map_sk_acquire net/core/sock_map.c:118 [inline] #1: ffffffff8d7b0e20 (rcu_read_lock){....}-{1:2}, at: sock_map_update_elem_sys+0x1d8/0x570 net/core/sock_map.c:578 #2: ffff888046786e68 (&htab->buckets[i].lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #2: ffff888046786e68 (&htab->buckets[i].lock){+.-.}-{2:2}, at: sock_hash_update_common+0x1fe/0xa60 net/core/sock_map.c:1013 stack backtrace: CPU: 2 PID: 24286 Comm: syz-executor.1 Not tainted 6.9.0-rc7-syzkaller-00023-g6d7ddd805123 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] sock_map_add_link net/core/sock_map.c:134 [inline] sock_hash_update_common+0x422/0xa60 net/core/sock_map.c:1029 sock_map_update_elem_sys+0x280/0x570 net/core/sock_map.c:584 bpf_map_update_value+0x36c/0x6c0 kernel/bpf/syscall.c:172 map_update_elem+0x623/0x910 kernel/bpf/syscall.c:1641 __sys_bpf+0xab9/0x4b40 kernel/bpf/syscall.c:5648 __do_sys_bpf kernel/bpf/syscall.c:5767 [inline] __se_sys_bpf kernel/bpf/syscall.c:5765 [inline] __x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:5765 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4278a7dd69 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f42797590c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f4278babf80 RCX: 00007f4278a7dd69 RDX: 0000000000000020 RSI: 0000000020000180 RDI: 0000000000000002 RBP: 00007f4278aca49e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f4278babf80 R15: 00007ffc37afd248