====================================================== WARNING: possible circular locking dependency detected 6.9.0-rc5-syzkaller-00185-g3e9bc0472b91 #0 Not tainted ------------------------------------------------------ syz-executor.2/5404 is trying to acquire lock: ffff88807e158bf0 (clock-AF_UNIX){+...}-{2:2}, at: sk_psock_drop+0x34/0x500 net/core/skmsg.c:837 but task is already holding lock: ffff88807e715200 (&stab->lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88807e715200 (&stab->lock){+.-.}-{2:2}, at: __sock_map_delete net/core/sock_map.c:417 [inline] ffff88807e715200 (&stab->lock){+.-.}-{2:2}, at: sock_map_delete_elem+0x175/0x250 net/core/sock_map.c:449 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&stab->lock){+.-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] __sock_map_delete net/core/sock_map.c:417 [inline] sock_map_delete_elem+0x175/0x250 net/core/sock_map.c:449 bpf_prog_300f72faed0bea10+0x62/0x67 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_run4+0x25a/0x490 kernel/trace/bpf_trace.c:2422 trace_mm_page_alloc include/trace/events/kmem.h:177 [inline] __alloc_pages+0x694/0x6c0 mm/page_alloc.c:4597 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page+0x5f/0x160 mm/slub.c:2175 allocate_slab mm/slub.c:2338 [inline] new_slab+0x84/0x2f0 mm/slub.c:2391 ___slab_alloc+0xc73/0x1260 mm/slub.c:3525 __slab_alloc mm/slub.c:3610 [inline] __slab_alloc_node mm/slub.c:3663 [inline] slab_alloc_node mm/slub.c:3835 [inline] kmalloc_node_trace+0x264/0x3a0 mm/slub.c:4005 kmalloc_node include/linux/slab.h:644 [inline] kzalloc_node include/linux/slab.h:760 [inline] sk_psock_init+0x144/0x750 net/core/skmsg.c:717 sock_map_link+0x76b/0xe40 net/core/sock_map.c:275 sock_hash_update_common+0xd1/0xa30 net/core/sock_map.c:1003 sock_map_update_elem_sys+0x5a4/0x910 net/core/sock_map.c:584 map_update_elem+0x53a/0x6f0 kernel/bpf/syscall.c:1641 __sys_bpf+0x76f/0x810 kernel/bpf/syscall.c:5653 __do_sys_bpf kernel/bpf/syscall.c:5772 [inline] __se_sys_bpf kernel/bpf/syscall.c:5770 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5770 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (clock-AF_UNIX){+...}-{2:2}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_write_lock_bh include/linux/rwlock_api_smp.h:202 [inline] _raw_write_lock_bh+0x35/0x50 kernel/locking/spinlock.c:334 sk_psock_drop+0x34/0x500 net/core/skmsg.c:837 __sock_map_delete net/core/sock_map.c:423 [inline] sock_map_delete_elem+0x1a2/0x250 net/core/sock_map.c:449 bpf_prog_8a405b5ced52e191+0x4a/0x4e bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline] __bpf_prog_run include/linux/filter.h:650 [inline] bpf_prog_run include/linux/filter.h:664 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline] bpf_trace_run4+0x3d7/0x490 kernel/trace/bpf_trace.c:2422 trace_ext4_writepages_result+0x1cc/0x230 include/trace/events/ext4.h:542 ext4_do_writepages+0x372f/0x3d40 fs/ext4/inode.c:2747 ext4_writepages+0x213/0x3c0 fs/ext4/inode.c:2768 do_writepages+0x359/0x870 mm/page-writeback.c:2612 filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:397 __filemap_fdatawrite_range mm/filemap.c:430 [inline] file_write_and_wait_range+0x1aa/0x290 mm/filemap.c:788 ext4_sync_file+0x260/0xb90 fs/ext4/fsync.c:158 generic_write_sync include/linux/fs.h:2795 [inline] ext4_buffered_write_iter+0x286/0x350 fs/ext4/file.c:305 ext4_file_write_iter+0x1de/0x1a10 call_write_iter include/linux/fs.h:2110 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa84/0xcb0 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 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(&stab->lock); lock(clock-AF_UNIX); lock(&stab->lock); lock(clock-AF_UNIX); *** DEADLOCK *** 5 locks held by syz-executor.2/5404: #0: ffff88802dd634c8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x259/0x320 fs/file.c:1191 #1: ffff88807ccdc420 (sb_writers#4){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2855 [inline] #1: ffff88807ccdc420 (sb_writers#4){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586 #2: ffff88807ccdeb98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1769 [inline] #2: ffff88807ccdeb98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1bf/0x3c0 fs/ext4/inode.c:2767 #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline] #3: ffffffff8e334d20 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x16e/0x490 kernel/trace/bpf_trace.c:2422 #4: ffff88807e715200 (&stab->lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #4: ffff88807e715200 (&stab->lock){+.-.}-{2:2}, at: __sock_map_delete net/core/sock_map.c:417 [inline] #4: ffff88807e715200 (&stab->lock){+.-.}-{2:2}, at: sock_map_delete_elem+0x175/0x250 net/core/sock_map.c:449 stack backtrace: CPU: 1 PID: 5404 Comm: syz-executor.2 Not tainted 6.9.0-rc5-syzkaller-00185-g3e9bc0472b91 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 check_noncircular+0x36a/0x4a0 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+0x18cb/0x58e0 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_write_lock_bh include/linux/rwlock_api_smp.h:202 [inline] _raw_write_lock_bh+0x35/0x50 kernel/locking/spinlock.c:334 sk_psock_drop+0x34/0x500 net/core/skmsg.c:837 __sock_map_delete net/core/sock_map.c:423 [inline] sock_map_delete_elem+0x1a2/0x250 net/core/sock_map.c:449 bpf_prog_8a405b5ced52e191+0x4a/0x4e bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline] __bpf_prog_run include/linux/filter.h:650 [inline] bpf_prog_run include/linux/filter.h:664 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline] bpf_trace_run4+0x3d7/0x490 kernel/trace/bpf_trace.c:2422 trace_ext4_writepages_result+0x1cc/0x230 include/trace/events/ext4.h:542 ext4_do_writepages+0x372f/0x3d40 fs/ext4/inode.c:2747 ext4_writepages+0x213/0x3c0 fs/ext4/inode.c:2768 do_writepages+0x359/0x870 mm/page-writeback.c:2612 filemap_fdatawrite_wbc+0x125/0x180 mm/filemap.c:397 __filemap_fdatawrite_range mm/filemap.c:430 [inline] file_write_and_wait_range+0x1aa/0x290 mm/filemap.c:788 ext4_sync_file+0x260/0xb90 fs/ext4/fsync.c:158 generic_write_sync include/linux/fs.h:2795 [inline] ext4_buffered_write_iter+0x286/0x350 fs/ext4/file.c:305 ext4_file_write_iter+0x1de/0x1a10 call_write_iter include/linux/fs.h:2110 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa84/0xcb0 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f72aaa7dea9 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:00007f72ab82a0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f72aababf80 RCX: 00007f72aaa7dea9 RDX: 0000000000002000 RSI: 0000000020000180 RDI: 0000000000000004 RBP: 00007f72aaaca4a4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f72aababf80 R15: 00007ffdd83d9778