Unable to handle kernel paging request at virtual address dfff800000000004 KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027] Mem abort info: ESR = 0x0000000096000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x06: level 2 translation fault Data abort info: ISV = 0, ISS = 0x00000006 CM = 0, WnR = 0 [dfff800000000004] address between user and kernel address ranges Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 4454 Comm: syz.0.16 Not tainted 6.1.144-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : qdisc_tree_reduce_backlog+0x1e8/0x410 net/sched/sch_api.c:802 lr : qdisc_tree_reduce_backlog+0x19c/0x410 net/sched/sch_api.c:794 sp : ffff800020d16d80 x29: ffff800020d16d80 x28: 0000000000000004 x27: dfff800000000000 x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000020 x23: 00000000000bffe6 x22: ffff80001775e5e0 x21: ffff0000cd9f1000 x20: 0000000000000000 x19: 0000000000000000 x18: 0000000000000000 x17: ffff8000181e6000 x16: ffff8000082d0f50 x15: 0000000000000000 x14: 00000000ffffffff x13: 0000000000ff0100 x12: 0000000000ff0100 x11: ff0080000febb728 x10: 0000000000000000 x9 : ffff0000d4a18000 x8 : 0000000000000000 x7 : ffff80000febbedc x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000002 x2 : 0000000000000008 x1 : 0000000000000000 x0 : 0000000000000000 Call trace: qdisc_tree_reduce_backlog+0x1e8/0x410 net/sched/sch_api.c:802 codel_change+0x740/0xb3c net/sched/sch_codel.c:177 codel_init+0x174/0x340 net/sched/sch_codel.c:196 qdisc_create+0x6f0/0xe20 net/sched/sch_api.c:1310 tc_modify_qdisc+0x954/0x1718 net/sched/sch_api.c:-1 rtnetlink_rcv_msg+0x734/0xce4 net/core/rtnetlink.c:6153 netlink_rcv_skb+0x208/0x3c4 net/netlink/af_netlink.c:2493 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6171 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline] netlink_unicast+0x600/0x818 net/netlink/af_netlink.c:1337 netlink_sendmsg+0x6e8/0x9b0 net/netlink/af_netlink.c:1859 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x5b8/0x918 net/socket.c:2519 ___sys_sendmsg net/socket.c:2573 [inline] __sys_sendmsg+0x25c/0x320 net/socket.c:2602 __do_sys_sendmsg net/socket.c:2611 [inline] __se_sys_sendmsg net/socket.c:2609 [inline] __arm64_sys_sendmsg+0x80/0x94 net/socket.c:2609 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Code: 14000020 f9400339 91008338 d343ff1c (387b6b88) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: 14000020 b 0x80 4: f9400339 ldr x25, [x25] 8: 91008338 add x24, x25, #0x20 c: d343ff1c lsr x28, x24, #3 * 10: 387b6b88 ldrb w8, [x28, x27] <-- trapping instruction