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BUG: KASAN: null-ptr-deref in memset include/linux/string.h:332 [inline]
BUG: KASAN: null-ptr-deref in choke_reset+0x1fc/0x330 net/sched/sch_choke.c:330
Write of size 8 at addr           (null) by task syz-executor.2/29060

CPU: 0 PID: 29060 Comm: syz-executor.2 Not tainted 4.14.180-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x13e/0x194 lib/dump_stack.c:58
 kasan_report_error mm/kasan/report.c:349 [inline]
 kasan_report mm/kasan/report.c:409 [inline]
 kasan_report.cold+0x127/0x2ae mm/kasan/report.c:393
 memset+0x20/0x40 mm/kasan/kasan.c:285
 memset include/linux/string.h:332 [inline]
 choke_reset+0x1fc/0x330 net/sched/sch_choke.c:330
 qdisc_reset+0x61/0x1e0 net/sched/sch_generic.c:678
 dev_deactivate_queue.constprop.0+0xc5/0x150 net/sched/sch_generic.c:867
 netdev_for_each_tx_queue include/linux/netdevice.h:1970 [inline]
 dev_deactivate_many+0xd6/0x960 net/sched/sch_generic.c:922
 dev_deactivate+0xe2/0x190 net/sched/sch_generic.c:955
 qdisc_graft+0x989/0xcd0 net/sched/sch_api.c:919
 tc_modify_qdisc+0x99e/0x1181 net/sched/sch_api.c:1446
 rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4315
 netlink_rcv_skb+0x127/0x370 net/netlink/af_netlink.c:2433
 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline]
 netlink_unicast+0x437/0x620 net/netlink/af_netlink.c:1313
 netlink_sendmsg+0x733/0xbe0 net/netlink/af_netlink.c:1878
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xc5/0x100 net/socket.c:656
 ___sys_sendmsg+0x70a/0x840 net/socket.c:2062
 __sys_sendmsg+0xa3/0x120 net/socket.c:2096
 SYSC_sendmsg net/socket.c:2107 [inline]
 SyS_sendmsg+0x27/0x40 net/socket.c:2103
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45ca29
RSP: 002b:00007f65db239c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000500f80 RCX: 000000000045ca29
RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000005
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000a05 R14: 00000000004ccddd R15: 00007f65db23a6d4
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