============================================ WARNING: possible recursive locking detected 6.9.0-syzkaller-12124-g96a27ee76f0e #0 Not tainted -------------------------------------------- syz-executor.0/7235 is trying to acquire lock: ffff88806194b260 (&htab->buckets[i].lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88806194b260 (&htab->buckets[i].lock){+.-.}-{2:2}, at: sock_hash_delete_elem+0x17c/0x400 net/core/sock_map.c:957 but task is already holding lock: ffff88804fb15a68 (&htab->buckets[i].lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88804fb15a68 (&htab->buckets[i].lock){+.-.}-{2:2}, at: sock_hash_delete_elem+0x17c/0x400 net/core/sock_map.c:957 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&htab->buckets[i].lock); lock(&htab->buckets[i].lock); *** DEADLOCK *** May be due to missing lock nesting notation 7 locks held by syz-executor.0/7235: #0: ffff88802f7e6420 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:409 #1: ffff88806046ca00 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:791 [inline] #1: ffff88806046ca00 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: open_last_lookups fs/namei.c:3571 [inline] #1: ffff88806046ca00 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: path_openat+0x7d3/0x3280 fs/namei.c:3804 #2: ffff88802f7ea950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x203f/0x22a0 fs/jbd2/transaction.c:463 #3: ffffffff8e333e60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #3: ffffffff8e333e60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #3: ffffffff8e333e60 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2402 [inline] #3: ffffffff8e333e60 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run3+0x24c/0x5a0 kernel/trace/bpf_trace.c:2445 #4: ffff88804fb15a68 (&htab->buckets[i].lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #4: ffff88804fb15a68 (&htab->buckets[i].lock){+.-.}-{2:2}, at: sock_hash_delete_elem+0x17c/0x400 net/core/sock_map.c:957 #5: ffff88807dda52b0 (&psock->link_lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #5: ffff88807dda52b0 (&psock->link_lock){+...}-{2:2}, at: sock_map_del_link net/core/sock_map.c:157 [inline] #5: ffff88807dda52b0 (&psock->link_lock){+...}-{2:2}, at: sock_map_unref+0xcc/0x5e0 net/core/sock_map.c:192 #6: ffffffff8e333e60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #6: ffffffff8e333e60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #6: ffffffff8e333e60 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2402 [inline] #6: ffffffff8e333e60 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run2+0x1fc/0x540 kernel/trace/bpf_trace.c:2444 stack backtrace: CPU: 1 PID: 7235 Comm: syz-executor.0 Not tainted 6.9.0-syzkaller-12124-g96a27ee76f0e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 check_deadlock kernel/locking/lockdep.c:3062 [inline] validate_chain+0x15d3/0x5900 kernel/locking/lockdep.c:3856 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 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_hash_delete_elem+0x17c/0x400 net/core/sock_map.c:957 bpf_prog_9dc0996bccb7470f+0x68/0x6c bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline] __bpf_prog_run include/linux/filter.h:691 [inline] bpf_prog_run include/linux/filter.h:698 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2403 [inline] bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2444 trace_kfree include/trace/events/kmem.h:94 [inline] kfree+0x2bb/0x360 mm/slub.c:4544 sk_psock_free_link include/linux/skmsg.h:423 [inline] sock_map_del_link net/core/sock_map.c:170 [inline] sock_map_unref+0x3ac/0x5e0 net/core/sock_map.c:192 sock_hash_delete_elem+0x392/0x400 net/core/sock_map.c:961 bpf_prog_fa3104b3f5a80c99+0x47/0x5c bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline] __bpf_prog_run include/linux/filter.h:691 [inline] bpf_prog_run include/linux/filter.h:698 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2403 [inline] bpf_trace_run3+0x33a/0x5a0 kernel/trace/bpf_trace.c:2445 trace_ext4_allocate_inode+0x1c1/0x230 include/trace/events/ext4.h:218 __ext4_new_inode+0x36fd/0x4390 fs/ext4/ialloc.c:1351 ext4_create+0x279/0x550 fs/ext4/namei.c:2830 lookup_open fs/namei.c:3505 [inline] open_last_lookups fs/namei.c:3574 [inline] path_openat+0x1425/0x3280 fs/namei.c:3804 do_filp_open+0x235/0x490 fs/namei.c:3834 do_sys_openat2+0x13e/0x1d0 fs/open.c:1405 do_sys_open fs/open.c:1420 [inline] __do_sys_openat fs/open.c:1436 [inline] __se_sys_openat fs/open.c:1431 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1431 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff6dda7cee9 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:00007ff6de8800c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007ff6ddbb4140 RCX: 00007ff6dda7cee9 RDX: 00000000000026e1 RSI: 0000000020000180 RDI: ffffffffffffff9c RBP: 00007ff6ddac947f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007ff6ddbb4140 R15: 00007ffef535d9e8