netlink: 52 bytes leftover after parsing attributes in process `syz.2.302'. ====================================================== WARNING: possible circular locking dependency detected 5.15.173-syzkaller #0 Not tainted ------------------------------------------------------ syz.2.302/5036 is trying to acquire lock: ffff0000e3550ca0 (msk_lock-AF_INET){+.+.}-{0:0}, at: inet_sk_diag_fill+0xcb8/0x17b4 net/ipv4/inet_diag.c:342 but task is already holding lock: ffff0000c5621ee8 (&h->lhash2[i].lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:363 [inline] ffff0000c5621ee8 (&h->lhash2[i].lock){+.+.}-{2:2}, at: mptcp_diag_dump_listeners net/mptcp/mptcp_diag.c:95 [inline] ffff0000c5621ee8 (&h->lhash2[i].lock){+.+.}-{2:2}, at: mptcp_diag_dump+0x7b0/0x10dc net/mptcp/mptcp_diag.c:194 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&h->lhash2[i].lock){+.+.}-{2:2}: __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0xb0/0x10c kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:363 [inline] inet_unhash+0xc4/0x6bc net/ipv4/inet_hashtables.c:658 tcp_set_state+0x590/0xb1c net/ipv4/tcp.c:2632 __tcp_close+0x9c/0x10dc net/ipv4/tcp.c:2757 __mptcp_close_ssk+0x1e8/0x4a0 net/mptcp/protocol.c:2328 __mptcp_destroy_sock+0x37c/0x6a4 net/mptcp/protocol.c:2761 mptcp_close+0x618/0xab0 net/mptcp/protocol.c:2818 inet_release+0x160/0x1d0 net/ipv4/af_inet.c:434 __sock_release net/socket.c:649 [inline] sock_close+0xb8/0x1fc net/socket.c:1336 __fput+0x1c4/0x800 fs/file_table.c:280 ____fput+0x20/0x30 fs/file_table.c:308 task_work_run+0x130/0x1e4 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] do_notify_resume+0x262c/0x32b8 arch/arm64/kernel/signal.c:946 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline] el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:609 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 -> #1 (k-sk_lock-AF_INET/1){+.+.}-{0:0}: lock_sock_fast_nested include/net/sock.h:1718 [inline] mptcp_close+0x2e0/0xab0 net/mptcp/protocol.c:2800 inet_release+0x160/0x1d0 net/ipv4/af_inet.c:434 __sock_release net/socket.c:649 [inline] sock_release+0x84/0x140 net/socket.c:677 mptcp_pm_nl_create_listen_socket net/mptcp/pm_netlink.c:1004 [inline] mptcp_nl_cmd_add_addr+0x978/0xbb0 net/mptcp/pm_netlink.c:1306 genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline] genl_family_rcv_msg net/netlink/genetlink.c:775 [inline] genl_rcv_msg+0xc18/0x1018 net/netlink/genetlink.c:792 netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2504 genl_rcv+0x38/0x50 net/netlink/genetlink.c:803 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x664/0x938 net/netlink/af_netlink.c:1352 netlink_sendmsg+0x844/0xb38 net/netlink/af_netlink.c:1920 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x584/0x870 net/socket.c:2436 ___sys_sendmsg+0x214/0x294 net/socket.c:2490 __sys_sendmsg net/socket.c:2519 [inline] __do_sys_sendmsg net/socket.c:2528 [inline] __se_sys_sendmsg net/socket.c:2526 [inline] __arm64_sys_sendmsg+0x1ac/0x25c net/socket.c:2526 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 -> #0 (msk_lock-AF_INET){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x32d4/0x7638 kernel/locking/lockdep.c:5012 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 lock_sock_fast include/net/sock.h:1710 [inline] mptcp_diag_get_info+0x208/0x8a0 net/mptcp/mptcp_diag.c:224 inet_sk_diag_fill+0xcb8/0x17b4 net/ipv4/inet_diag.c:342 sk_diag_dump net/mptcp/mptcp_diag.c:24 [inline] mptcp_diag_dump_listeners net/mptcp/mptcp_diag.c:122 [inline] mptcp_diag_dump+0xb4c/0x10dc net/mptcp/mptcp_diag.c:194 __inet_diag_dump+0x1e8/0x33c net/ipv4/inet_diag.c:1179 inet_diag_dump_compat+0x17c/0x288 net/ipv4/inet_diag.c:1288 netlink_dump+0x4a8/0xad0 net/netlink/af_netlink.c:2280 __netlink_dump_start+0x474/0x6d4 net/netlink/af_netlink.c:2383 netlink_dump_start include/linux/netlink.h:258 [inline] inet_diag_rcv_msg_compat+0x1c8/0x434 net/ipv4/inet_diag.c:1323 sock_diag_rcv_msg+0x174/0x39c netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2504 sock_diag_rcv+0x3c/0x54 net/core/sock_diag.c:276 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x664/0x938 net/netlink/af_netlink.c:1352 netlink_sendmsg+0x844/0xb38 net/netlink/af_netlink.c:1920 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x584/0x870 net/socket.c:2436 ___sys_sendmsg+0x214/0x294 net/socket.c:2490 __sys_sendmsg net/socket.c:2519 [inline] __do_sys_sendmsg net/socket.c:2528 [inline] __se_sys_sendmsg net/socket.c:2526 [inline] __arm64_sys_sendmsg+0x1ac/0x25c net/socket.c:2526 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 other info that might help us debug this: Chain exists of: msk_lock-AF_INET --> k-sk_lock-AF_INET/1 --> &h->lhash2[i].lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&h->lhash2[i].lock); lock(k-sk_lock-AF_INET/1); lock(&h->lhash2[i].lock); lock(msk_lock-AF_INET); *** DEADLOCK *** 6 locks held by syz.2.302/5036: #0: ffff800016bfdac8 (sock_diag_mutex){+.+.}-{3:3}, at: sock_diag_rcv+0x2c/0x54 net/core/sock_diag.c:275 #1: ffff800016bfd928 (sock_diag_table_mutex){+.+.}-{3:3}, at: sock_diag_rcv_msg+0x15c/0x39c net/core/sock_diag.c:255 #2: ffff0000cda14690 (nlk_cb_mutex-SOCK_DIAG){+.+.}-{3:3}, at: __netlink_dump_start+0x108/0x6d4 net/netlink/af_netlink.c:2349 #3: ffff800016cd6f28 (inet_diag_table_mutex){+.+.}-{3:3}, at: inet_diag_lock_handler net/ipv4/inet_diag.c:63 [inline] #3: ffff800016cd6f28 (inet_diag_table_mutex){+.+.}-{3:3}, at: __inet_diag_dump+0x17c/0x33c net/ipv4/inet_diag.c:1177 #4: ffff800014c922e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:311 #5: ffff0000c5621ee8 (&h->lhash2[i].lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:363 [inline] #5: ffff0000c5621ee8 (&h->lhash2[i].lock){+.+.}-{2:2}, at: mptcp_diag_dump_listeners net/mptcp/mptcp_diag.c:95 [inline] #5: ffff0000c5621ee8 (&h->lhash2[i].lock){+.+.}-{2:2}, at: mptcp_diag_dump+0x7b0/0x10dc net/mptcp/mptcp_diag.c:194 stack backtrace: CPU: 1 PID: 5036 Comm: syz.2.302 Not tainted 5.15.173-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 dump_stack+0x1c/0x58 lib/dump_stack.c:113 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2011 check_noncircular+0x2cc/0x378 kernel/locking/lockdep.c:2133 check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire+0x32d4/0x7638 kernel/locking/lockdep.c:5012 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 lock_sock_fast include/net/sock.h:1710 [inline] mptcp_diag_get_info+0x208/0x8a0 net/mptcp/mptcp_diag.c:224 inet_sk_diag_fill+0xcb8/0x17b4 net/ipv4/inet_diag.c:342 sk_diag_dump net/mptcp/mptcp_diag.c:24 [inline] mptcp_diag_dump_listeners net/mptcp/mptcp_diag.c:122 [inline] mptcp_diag_dump+0xb4c/0x10dc net/mptcp/mptcp_diag.c:194 __inet_diag_dump+0x1e8/0x33c net/ipv4/inet_diag.c:1179 inet_diag_dump_compat+0x17c/0x288 net/ipv4/inet_diag.c:1288 netlink_dump+0x4a8/0xad0 net/netlink/af_netlink.c:2280 __netlink_dump_start+0x474/0x6d4 net/netlink/af_netlink.c:2383 netlink_dump_start include/linux/netlink.h:258 [inline] inet_diag_rcv_msg_compat+0x1c8/0x434 net/ipv4/inet_diag.c:1323 sock_diag_rcv_msg+0x174/0x39c netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2504 sock_diag_rcv+0x3c/0x54 net/core/sock_diag.c:276 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x664/0x938 net/netlink/af_netlink.c:1352 netlink_sendmsg+0x844/0xb38 net/netlink/af_netlink.c:1920 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x584/0x870 net/socket.c:2436 ___sys_sendmsg+0x214/0x294 net/socket.c:2490 __sys_sendmsg net/socket.c:2519 [inline] __do_sys_sendmsg net/socket.c:2528 [inline] __se_sys_sendmsg net/socket.c:2526 [inline] __arm64_sys_sendmsg+0x1ac/0x25c net/socket.c:2526 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 BUG: sleeping function called from invalid context at net/core/sock.c:3282 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 5036, name: syz.2.302 INFO: lockdep is turned off. Preemption disabled at: [] spin_lock include/linux/spinlock.h:363 [inline] [] mptcp_diag_dump_listeners net/mptcp/mptcp_diag.c:95 [inline] [] mptcp_diag_dump+0x7b0/0x10dc net/mptcp/mptcp_diag.c:194 CPU: 1 PID: 5036 Comm: syz.2.302 Not tainted 5.15.173-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 dump_stack+0x1c/0x58 lib/dump_stack.c:113 ___might_sleep+0x380/0x4dc kernel/sched/core.c:9636 __might_sleep+0x98/0xf0 kernel/sched/core.c:9590 __lock_sock_fast+0x3c/0xf0 net/core/sock.c:3282 lock_sock_fast include/net/sock.h:1712 [inline] mptcp_diag_get_info+0x210/0x8a0 net/mptcp/mptcp_diag.c:224 inet_sk_diag_fill+0xcb8/0x17b4 net/ipv4/inet_diag.c:342 sk_diag_dump net/mptcp/mptcp_diag.c:24 [inline] mptcp_diag_dump_listeners net/mptcp/mptcp_diag.c:122 [inline] mptcp_diag_dump+0xb4c/0x10dc net/mptcp/mptcp_diag.c:194 __inet_diag_dump+0x1e8/0x33c net/ipv4/inet_diag.c:1179 inet_diag_dump_compat+0x17c/0x288 net/ipv4/inet_diag.c:1288 netlink_dump+0x4a8/0xad0 net/netlink/af_netlink.c:2280 __netlink_dump_start+0x474/0x6d4 net/netlink/af_netlink.c:2383 netlink_dump_start include/linux/netlink.h:258 [inline] inet_diag_rcv_msg_compat+0x1c8/0x434 net/ipv4/inet_diag.c:1323 sock_diag_rcv_msg+0x174/0x39c netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2504 sock_diag_rcv+0x3c/0x54 net/core/sock_diag.c:276 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline] netlink_unicast+0x664/0x938 net/netlink/af_netlink.c:1352 netlink_sendmsg+0x844/0xb38 net/netlink/af_netlink.c:1920 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x584/0x870 net/socket.c:2436 ___sys_sendmsg+0x214/0x294 net/socket.c:2490 __sys_sendmsg net/socket.c:2519 [inline] __do_sys_sendmsg net/socket.c:2528 [inline] __se_sys_sendmsg net/socket.c:2526 [inline] __arm64_sys_sendmsg+0x1ac/0x25c net/socket.c:2526 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584