general protection fault, probably for non-canonical address 0xdffffc000000000b: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000058-0x000000000000005f] CPU: 0 PID: 5958 Comm: syz.0.456 Not tainted 5.15.188-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:__list_del_entry_valid+0x1f/0x120 lib/list_debug.c:46 Code: de 4c 89 f1 e8 52 4d bf 05 0f 0b 41 57 41 56 41 54 53 48 89 fb 49 bc 00 00 00 00 00 fc ff df 48 83 c7 08 48 89 f8 48 c1 e8 03 <42> 80 3c 20 00 74 05 e8 45 7a dd fd 4c 8b 7b 08 48 89 d8 48 c1 e8 RSP: 0018:ffffc90003b8eed0 EFLAGS: 00010202 RAX: 000000000000000b RBX: 0000000000000050 RCX: 0000000000080000 RDX: ffffc90005b49000 RSI: 000000000000033d RDI: 0000000000000058 RBP: 1ffffffff1605308 R08: ffff8880206c5940 R09: 0000000000000002 R10: 00000000ffffffff R11: 0000000000000002 R12: dffffc0000000000 R13: dffffc0000000000 R14: 0000000000000050 R15: ffffffff8b029840 FS: 00007fa02bd036c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31818ff8 CR3: 000000007439f000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __list_del_entry include/linux/list.h:132 [inline] list_del include/linux/list.h:146 [inline] drr_qlen_notify+0x28/0x100 net/sched/sch_drr.c:238 qdisc_tree_reduce_backlog+0x25f/0x430 net/sched/sch_api.c:799 fq_codel_change+0xa71/0xf10 net/sched/sch_fq_codel.c:438 fq_codel_init+0x319/0x8f0 net/sched/sch_fq_codel.c:475 qdisc_create+0x7bd/0x1170 net/sched/sch_api.c:1260 tc_modify_qdisc+0xaad/0x16c0 net/sched/sch_api.c:-1 rtnetlink_rcv_msg+0x9b9/0xe60 net/core/rtnetlink.c:5650 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2489 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline] netlink_unicast+0x77c/0x920 net/netlink/af_netlink.c:1337 netlink_sendmsg+0x8ab/0xbc0 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2436 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2490 __sys_sendmsg net/socket.c:2519 [inline] __do_sys_sendmsg net/socket.c:2528 [inline] __se_sys_sendmsg+0x190/0x250 net/socket.c:2526 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fa02de9b929 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:00007fa02bd03038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fa02e0c2fa0 RCX: 00007fa02de9b929 RDX: 0000000000004000 RSI: 0000200000000040 RDI: 0000000000000006 RBP: 00007fa02df1db39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fa02e0c2fa0 R15: 00007fffcb924038 Modules linked in: ---[ end trace e99b7c650c273d86 ]--- RIP: 0010:__list_del_entry_valid+0x1f/0x120 lib/list_debug.c:46 Code: de 4c 89 f1 e8 52 4d bf 05 0f 0b 41 57 41 56 41 54 53 48 89 fb 49 bc 00 00 00 00 00 fc ff df 48 83 c7 08 48 89 f8 48 c1 e8 03 <42> 80 3c 20 00 74 05 e8 45 7a dd fd 4c 8b 7b 08 48 89 d8 48 c1 e8 RSP: 0018:ffffc90003b8eed0 EFLAGS: 00010202 RAX: 000000000000000b RBX: 0000000000000050 RCX: 0000000000080000 RDX: ffffc90005b49000 RSI: 000000000000033d RDI: 0000000000000058 RBP: 1ffffffff1605308 R08: ffff8880206c5940 R09: 0000000000000002 R10: 00000000ffffffff R11: 0000000000000002 R12: dffffc0000000000 R13: dffffc0000000000 R14: 0000000000000050 R15: ffffffff8b029840 FS: 00007fa02bd036c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b31818ff8 CR3: 000000007439f000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: de 4c 89 f1 fimuls -0xf(%rcx,%rcx,4) 4: e8 52 4d bf 05 call 0x5bf4d5b 9: 0f 0b ud2 b: 41 57 push %r15 d: 41 56 push %r14 f: 41 54 push %r12 11: 53 push %rbx 12: 48 89 fb mov %rdi,%rbx 15: 49 bc 00 00 00 00 00 movabs $0xdffffc0000000000,%r12 1c: fc ff df 1f: 48 83 c7 08 add $0x8,%rdi 23: 48 89 f8 mov %rdi,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) <-- trapping instruction 2f: 74 05 je 0x36 31: e8 45 7a dd fd call 0xfddd7a7b 36: 4c 8b 7b 08 mov 0x8(%rbx),%r15 3a: 48 89 d8 mov %rbx,%rax 3d: 48 rex.W 3e: c1 .byte 0xc1 3f: e8 .byte 0xe8