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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.3/15218

CPU: 0 PID: 15218 Comm: syz-executor.3 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_close_many+0x102/0x250 net/core/dev.c:1441
 __dev_close net/core/dev.c:1466 [inline]
 __dev_change_flags+0x205/0x510 net/core/dev.c:6795
 dev_change_flags+0x7e/0x130 net/core/dev.c:6863
 dev_ifsioc+0x23f/0x7e0 net/core/dev_ioctl.c:257
 dev_ioctl+0x23c/0xcb0 net/core/dev_ioctl.c:566
 sock_do_ioctl+0x8c/0xa0 net/socket.c:981
 sock_ioctl+0x28d/0x450 net/socket.c:1071
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x75a/0xfe0 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45ca29
RSP: 002b:00007f7641ef9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004e95c0 RCX: 000000000045ca29
RDX: 0000000020000040 RSI: 0000000000008914 RDI: 0000000000000006
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000041e R14: 00000000004d3b00 R15: 00007f7641efa6d4
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