netlink: 20 bytes leftover after parsing attributes in process `syz-executor.0'.
==================================================================
BUG: KASAN: slab-out-of-bounds in flush_gro_hash net/core/dev.c:6241 [inline]
BUG: KASAN: slab-out-of-bounds in netif_napi_del+0x301/0x380 net/core/dev.c:6256
Read of size 8 at addr ffff888053a89398 by task syz-executor.0/13738

CPU: 0 PID: 13738 Comm: syz-executor.0 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
 kasan_report mm/kasan/report.c:412 [inline]
 __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433
 flush_gro_hash net/core/dev.c:6241 [inline]
 netif_napi_del+0x301/0x380 net/core/dev.c:6256
 free_netdev+0x21f/0x410 net/core/dev.c:9250
 netdev_run_todo+0x89b/0xab0 net/core/dev.c:9002
 rtnl_unlock net/core/rtnetlink.c:117 [inline]
 rtnetlink_rcv_msg+0x460/0xb80 net/core/rtnetlink.c:4783
 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2463
 netlink_unicast_kernel net/netlink/af_netlink.c:1325 [inline]
 netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1351
 netlink_sendmsg+0x6c3/0xc50 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:661
 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2227
 __sys_sendmsg net/socket.c:2265 [inline]
 __do_sys_sendmsg net/socket.c:2274 [inline]
 __se_sys_sendmsg net/socket.c:2272 [inline]
 __x64_sys_sendmsg+0x132/0x220 net/socket.c:2272
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fd161f57279
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd1608cc168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fd162069f80 RCX: 00007fd161f57279
RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000004
RBP: 00007fd161fb1189 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe545a24af R14: 00007fd1608cc300 R15: 0000000000022000

Allocated by task 13748:
 __do_kmalloc_node mm/slab.c:3689 [inline]
 __kmalloc_node+0x4c/0x70 mm/slab.c:3696
 kmalloc_node include/linux/slab.h:557 [inline]
 kvmalloc_node+0xb4/0xf0 mm/util.c:423
 kvmalloc include/linux/mm.h:577 [inline]
 kvzalloc include/linux/mm.h:585 [inline]
 alloc_netdev_mqs+0x97/0xd50 net/core/dev.c:9152
 __tun_chr_ioctl.isra.0+0x2184/0x3d00 drivers/net/tun.c:2628
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688
 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 9467:
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xcc/0x210 mm/slab.c:3822
 device_release+0x76/0x210 drivers/base/core.c:1076
 kobject_cleanup lib/kobject.c:662 [inline]
 kobject_release lib/kobject.c:691 [inline]
 kref_put include/linux/kref.h:70 [inline]
 kobject_put+0x28b/0x5d0 lib/kobject.c:708
 put_device+0x1c/0x30 drivers/base/core.c:2267
 mac80211_hwsim_del_radio drivers/net/wireless/mac80211_hwsim.c:2998 [inline]
 hwsim_exit_net+0xbdf/0x1580 drivers/net/wireless/mac80211_hwsim.c:3666
 ops_exit_list+0xa5/0x150 net/core/net_namespace.c:153
 cleanup_net+0x3b4/0x8b0 net/core/net_namespace.c:554
 process_one_work+0x864/0x1570 kernel/workqueue.c:2153
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

The buggy address belongs to the object at ffff888053a89440
 which belongs to the cache kmalloc-16384 of size 16384
The buggy address is located 168 bytes to the left of
 16384-byte region [ffff888053a89440, ffff888053a8d440)
The buggy address belongs to the page:
page:ffffea00014ea200 count:1 mapcount:0 mapping:ffff88813bff2200 index:0x0 compound_mapcount: 0
flags: 0xfff00000008100(slab|head)
raw: 00fff00000008100 ffffea0001603e08 ffffea00024d5408 ffff88813bff2200
raw: 0000000000000000 ffff888053a89440 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888053a89280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888053a89300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888053a89380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                            ^
 ffff888053a89400: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
 ffff888053a89480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================