================================ WARNING: inconsistent lock state 5.15.167-syzkaller #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. syz.1.177/4560 [HC0[0]:SC1[1]:HE1:SE0] takes: ffff88801fc3d9e0 (&pch->downl){+.?.}-{2:2}, at: spin_lock include/linux/spinlock.h:363 [inline] ffff88801fc3d9e0 (&pch->downl){+.?.}-{2:2}, at: ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2271 [inline] ffff88801fc3d9e0 (&pch->downl){+.?.}-{2:2}, at: ppp_input+0x160/0x980 drivers/net/ppp/ppp_generic.c:2303 {SOFTIRQ-ON-W} state was registered at: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:363 [inline] ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2271 [inline] ppp_input+0x160/0x980 drivers/net/ppp/ppp_generic.c:2303 pppoe_rcv_core+0x109/0x2f0 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv include/net/sock.h:1059 [inline] __release_sock+0x198/0x4b0 net/core/sock.c:2724 release_sock+0x5d/0x1c0 net/core/sock.c:3265 pppoe_sendmsg+0xd1/0x740 drivers/net/ppp/pppoe.c:903 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2431 ___sys_sendmsg+0x252/0x2e0 net/socket.c:2485 __sys_sendmmsg+0x2bf/0x560 net/socket.c:2571 __do_sys_sendmmsg net/socket.c:2600 [inline] __se_sys_sendmmsg net/socket.c:2597 [inline] __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2597 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 irq event stamp: 3996 hardirqs last enabled at (3996): [] __local_bh_enable_ip+0x164/0x1f0 kernel/softirq.c:388 hardirqs last disabled at (3995): [] __local_bh_enable_ip+0x102/0x1f0 kernel/softirq.c:365 softirqs last enabled at (3964): [] pppoe_sendmsg+0xd1/0x740 drivers/net/ppp/pppoe.c:903 softirqs last disabled at (3969): [] __do_softirq kernel/softirq.c:592 [inline] softirqs last disabled at (3969): [] invoke_softirq kernel/softirq.c:432 [inline] softirqs last disabled at (3969): [] __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&pch->downl); lock(&pch->downl); *** DEADLOCK *** 5 locks held by syz.1.177/4560: #0: ffffffff8c91fc60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 #1: ffffffff8c91fc60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:312 #2: ffff8880771f60a0 (slock-AF_PPPOX){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:363 [inline] #2: ffff8880771f60a0 (slock-AF_PPPOX){+.-.}-{2:2}, at: __sk_receive_skb+0x17c/0x9c0 net/core/sock.c:521 #3: ffff8880771f6120 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: __netif_receive_skb_one_core net/core/dev.c:5485 [inline] #3: ffff8880771f6120 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: __netif_receive_skb+0x1c6/0x530 net/core/dev.c:5599 #4: ffffffff8c91fc60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 stack backtrace: CPU: 0 PID: 4560 Comm: syz.1.177 Not tainted 5.15.167-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 valid_state+0x134/0x1c0 kernel/locking/lockdep.c:3932 mark_lock_irq+0xa8/0xba0 kernel/locking/lockdep.c:4135 mark_lock+0x21a/0x340 kernel/locking/lockdep.c:4591 __lock_acquire+0xb9d/0x1ff0 kernel/locking/lockdep.c:4966 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:363 [inline] ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2271 [inline] ppp_input+0x160/0x980 drivers/net/ppp/ppp_generic.c:2303 pppoe_rcv_core+0x109/0x2f0 drivers/net/ppp/pppoe.c:379 sk_backlog_rcv include/net/sock.h:1059 [inline] __sk_receive_skb+0x416/0x9c0 net/core/sock.c:528 __netif_receive_skb_one_core net/core/dev.c:5485 [inline] __netif_receive_skb+0x1c6/0x530 net/core/dev.c:5599 process_backlog+0x363/0x7f0 net/core/dev.c:6476 __napi_poll+0xc7/0x440 net/core/dev.c:7035 napi_poll net/core/dev.c:7102 [inline] net_rx_action+0x617/0xda0 net/core/dev.c:7192 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558 __do_softirq kernel/softirq.c:592 [inline] invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641 irq_exit_rcu+0x5/0x20 kernel/softirq.c:653 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 f2 3e 8c f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 87 87 19 f7 65 8b 05 08 8a c4 75 85 c0 74 3f 48 c7 04 24 0e 36 RSP: 0018:ffffc90003387780 EFLAGS: 00000206 RAX: 6fb13edb15dc1100 RBX: 1ffff92000670ef4 RCX: ffffffff96868f03 RDX: dffffc0000000000 RSI: ffffffff8a8b2b00 RDI: 0000000000000001 RBP: ffffc90003387820 R08: ffffffff8186db50 R09: ffffed100c209635 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff92000670ef0 R14: ffffc900033877a0 R15: 0000000000000246 spin_unlock_irqrestore include/linux/spinlock.h:418 [inline] trie_delete_elem+0x52f/0x690 kernel/bpf/lpm_trie.c:526 bpf_prog_2c29ac5cdc6b1842+0x3a/0x7fc bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline] bpf_trace_run2+0x19e/0x340 kernel/trace/bpf_trace.c:1917 __bpf_trace_kfree+0x6e/0x90 include/trace/events/kmem.h:118 trace_kfree include/trace/events/kmem.h:118 [inline] kfree+0x22f/0x270 mm/slub.c:4549 ___sys_sendmsg+0x27b/0x2e0 net/socket.c:2487 __sys_sendmmsg+0x2bf/0x560 net/socket.c:2571 __do_sys_sendmmsg net/socket.c:2600 [inline] __se_sys_sendmmsg net/socket.c:2597 [inline] __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2597 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f40f2f54f39 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f40f13cd038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f40f310cf80 RCX: 00007f40f2f54f39 RDX: 0400000000000026 RSI: 0000000020001cc0 RDI: 0000000000000004 RBP: 00007f40f2fc7216 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f40f310cf80 R15: 00007ffdc7930f88 ---------------- Code disassembly (best guess): 0: 9c pushf 1: 8f 44 24 20 pop 0x20(%rsp) 5: 42 80 3c 23 00 cmpb $0x0,(%rbx,%r12,1) a: 74 08 je 0x14 c: 4c 89 f7 mov %r14,%rdi f: e8 f2 3e 8c f7 call 0xf78c3f06 14: f6 44 24 21 02 testb $0x2,0x21(%rsp) 19: 75 4e jne 0x69 1b: 41 f7 c7 00 02 00 00 test $0x200,%r15d 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 87 87 19 f7 call 0xf71987b6 <-- trapping instruction 2f: 65 8b 05 08 8a c4 75 mov %gs:0x75c48a08(%rip),%eax # 0x75c48a3e 36: 85 c0 test %eax,%eax 38: 74 3f je 0x79 3a: 48 rex.W 3b: c7 .byte 0xc7 3c: 04 24 add $0x24,%al 3e: 0e (bad) 3f: 36 ss