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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.2/29739

CPU: 0 PID: 29739 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_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
 do_setlink+0x91b/0x2c00 net/core/rtnetlink.c:2092
 rtnl_setlink+0x1f5/0x2e0 net/core/rtnetlink.c:2324
 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
 sock_write_iter+0x22c/0x370 net/socket.c:925
 call_write_iter include/linux/fs.h:1778 [inline]
 do_iter_readv_writev+0x3df/0x600 fs/read_write.c:675
 do_iter_write fs/read_write.c:954 [inline]
 do_iter_write+0x152/0x550 fs/read_write.c:935
 vfs_writev+0x170/0x2a0 fs/read_write.c:999
 do_writev+0xfc/0x2c0 fs/read_write.c:1034
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45ca29
RSP: 002b:00007f79760c3c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 000000000050d640 RCX: 000000000045ca29
RDX: 0000000000000001 RSI: 0000000020000040 RDI: 0000000000000005
RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000d20 R14: 00000000004cb469 R15: 00007f79760c46d4
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