BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 12254b067 P4D 12254b067 PUD 12246e067 PMD 0 Oops: 0002 [#1] PREEMPT SMP CPU: 0 PID: 14734 Comm: syz-executor.1 Not tainted 5.7.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:memset_erms+0x9/0x10 arch/x86/lib/memset_64.S:66 Code: c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 aa 4c 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 RSP: 0018:ffffc9001584b6f8 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000008 RDX: 0000000000000008 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff8880a1d3f400 R08: 0000000000000000 R09: 0000000000000000 R10: 00008880a1d3f4c8 R11: 00008880a1d3f4cb R12: ffff8880a1d3f670 R13: ffff8880a1d3f6a4 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f692d792700(0000) GS:ffff88812c000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000122bfa000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: memset include/linux/string.h:366 [inline] choke_reset+0x166/0x1e0 net/sched/sch_choke.c:326 qdisc_reset+0x59/0x300 net/sched/sch_generic.c:910 dev_deactivate_queue.constprop.0+0xdf/0x150 net/sched/sch_generic.c:1138 netdev_for_each_tx_queue include/linux/netdevice.h:2197 [inline] dev_deactivate_many+0xab/0x5b0 net/sched/sch_generic.c:1195 dev_deactivate+0xc8/0x160 net/sched/sch_generic.c:1233 qdisc_graft+0x939/0xae0 net/sched/sch_api.c:1051 tc_modify_qdisc+0x727/0x1000 net/sched/sch_api.c:1670 rtnetlink_rcv_msg+0x1d0/0x4e0 net/core/rtnetlink.c:5454 netlink_rcv_skb+0xaf/0x260 net/netlink/af_netlink.c:2469 rtnetlink_rcv+0x22/0x30 net/core/rtnetlink.c:5472 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x390/0x4c0 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x4cf/0x8a0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0x98/0xc0 net/socket.c:672 ____sys_sendmsg+0x493/0x4c0 net/socket.c:2362 ___sys_sendmsg+0xb5/0x100 net/socket.c:2416 __sys_sendmsg+0x9b/0x150 net/socket.c:2449 __do_sys_sendmsg net/socket.c:2458 [inline] __se_sys_sendmsg net/socket.c:2456 [inline] __x64_sys_sendmsg+0x4c/0x60 net/socket.c:2456 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45ca59 Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f692d791c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000501a60 RCX: 000000000045ca59 RDX: 0000000000000000 RSI: 0000000020000800 RDI: 0000000000000007 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000a22 R14: 00000000004cd04d R15: 00007f692d7926d4 Modules linked in: CR2: 0000000000000000 ---[ end trace 68f278a91453f3aa ]--- RIP: 0010:memset_erms+0x9/0x10 arch/x86/lib/memset_64.S:66 Code: c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 aa 4c 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 RSP: 0018:ffffc9001584b6f8 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000008 RDX: 0000000000000008 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff8880a1d3f400 R08: 0000000000000000 R09: 0000000000000000 R10: 00008880a1d3f4c8 R11: 00008880a1d3f4cb R12: ffff8880a1d3f670 R13: ffff8880a1d3f6a4 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f692d792700(0000) GS:ffff88812c000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000122bfa000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400