general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 PID: 8419 Comm: syz-executor210 Not tainted 5.14.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:dequeue_head net/sched/sch_fq_codel.c:120 [inline] RIP: 0010:fq_codel_drop net/sched/sch_fq_codel.c:168 [inline] RIP: 0010:fq_codel_enqueue+0xcf0/0x1560 net/sched/sch_fq_codel.c:230 Code: 8b 84 24 88 00 00 00 42 80 3c 20 00 48 8b 5c 24 40 74 08 48 89 df e8 ef 53 a4 f9 44 89 74 24 20 4c 8b 2b 4d 89 ef 49 c1 ef 03 <43> 80 3c 27 00 74 08 4c 89 ef e8 d1 53 a4 f9 4d 8b 75 00 4c 89 e3 RSP: 0018:ffffc9000ac96f40 EFLAGS: 00010246 RAX: 1ffff11007604000 RBX: ffff88803b020000 RCX: ffff88803b020000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000ac970d0 R08: ffffffff88252d1b R09: fffffbfff1f5e7d2 R10: fffffbfff1f5e7d2 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000001954300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f334775e6c0 CR3: 00000000345d7000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: dev_qdisc_enqueue net/core/dev.c:3854 [inline] __dev_xmit_skb net/core/dev.c:3938 [inline] __dev_queue_xmit+0xcaa/0x34b0 net/core/dev.c:4253 __bpf_tx_skb net/core/filter.c:2113 [inline] __bpf_redirect_common net/core/filter.c:2152 [inline] __bpf_redirect+0x9a0/0xe00 net/core/filter.c:2159 ____bpf_clone_redirect net/core/filter.c:2445 [inline] bpf_clone_redirect+0x243/0x350 net/core/filter.c:2417 bpf_prog_cc75667d52cf7bb0+0x56/0x528 bpf_dispatcher_nop_func include/linux/bpf.h:687 [inline] bpf_test_run+0x506/0xa60 net/bpf/test_run.c:118 bpf_prog_test_run_skb+0xa45/0x1df0 net/bpf/test_run.c:657 bpf_prog_test_run kernel/bpf/syscall.c:3207 [inline] __sys_bpf+0x5301/0x11d60 kernel/bpf/syscall.c:4487 __do_sys_bpf kernel/bpf/syscall.c:4573 [inline] __se_sys_bpf kernel/bpf/syscall.c:4571 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:4571 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x43f349 Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc0a371788 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043f349 RDX: 0000000000000048 RSI: 0000000020000140 RDI: 000000000000000a RBP: 0000000000403330 R08: 0000000000400488 R09: 0000000000400488 R10: 0000000000400488 R11: 0000000000000246 R12: 00000000004033c0 R13: 0000000000000000 R14: 00000000004ad018 R15: 0000000000400488 Modules linked in: ---[ end trace 801b0b210233ddfe ]--- RIP: 0010:dequeue_head net/sched/sch_fq_codel.c:120 [inline] RIP: 0010:fq_codel_drop net/sched/sch_fq_codel.c:168 [inline] RIP: 0010:fq_codel_enqueue+0xcf0/0x1560 net/sched/sch_fq_codel.c:230 Code: 8b 84 24 88 00 00 00 42 80 3c 20 00 48 8b 5c 24 40 74 08 48 89 df e8 ef 53 a4 f9 44 89 74 24 20 4c 8b 2b 4d 89 ef 49 c1 ef 03 <43> 80 3c 27 00 74 08 4c 89 ef e8 d1 53 a4 f9 4d 8b 75 00 4c 89 e3 RSP: 0018:ffffc9000ac96f40 EFLAGS: 00010246 RAX: 1ffff11007604000 RBX: ffff88803b020000 RCX: ffff88803b020000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000ac970d0 R08: ffffffff88252d1b R09: fffffbfff1f5e7d2 R10: fffffbfff1f5e7d2 R11: 0000000000000000 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000001954300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f334775e6c0 CR3: 00000000345d7000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 8b 84 24 88 00 00 00 mov 0x88(%rsp),%eax 7: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) c: 48 8b 5c 24 40 mov 0x40(%rsp),%rbx 11: 74 08 je 0x1b 13: 48 89 df mov %rbx,%rdi 16: e8 ef 53 a4 f9 callq 0xf9a4540a 1b: 44 89 74 24 20 mov %r14d,0x20(%rsp) 20: 4c 8b 2b mov (%rbx),%r13 23: 4d 89 ef mov %r13,%r15 26: 49 c1 ef 03 shr $0x3,%r15 * 2a: 43 80 3c 27 00 cmpb $0x0,(%r15,%r12,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 4c 89 ef mov %r13,%rdi 34: e8 d1 53 a4 f9 callq 0xf9a4540a 39: 4d 8b 75 00 mov 0x0(%r13),%r14 3d: 4c 89 e3 mov %r12,%rbx