netlink: 4 bytes leftover after parsing attributes in process `syz-executor.0'.
netlink: 24 bytes leftover after parsing attributes in process `syz-executor.2'.
==================================================================
BUG: KASAN: use-after-free in macvlan_dev_get_iflink+0x5f/0x70 syzkaller/managers/linux-4-14/kernel/drivers/net/macvlan.c:1101
Read of size 4 at addr ffff8880af2ae3c8 by task syz-executor.0/26281

CPU: 1 PID: 26281 Comm: syz-executor.0 Not tainted 4.14.218-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack syzkaller/managers/linux-4-14/kernel/lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 syzkaller/managers/linux-4-14/kernel/lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1d3 syzkaller/managers/linux-4-14/kernel/mm/kasan/report.c:252
 kasan_report_error.cold+0x8a/0x191 syzkaller/managers/linux-4-14/kernel/mm/kasan/report.c:351
 kasan_report syzkaller/managers/linux-4-14/kernel/mm/kasan/report.c:409 [inline]
 __asan_report_load4_noabort+0x68/0x70 syzkaller/managers/linux-4-14/kernel/mm/kasan/report.c:429
 macvlan_dev_get_iflink+0x5f/0x70 syzkaller/managers/linux-4-14/kernel/drivers/net/macvlan.c:1101
netlink: 12 bytes leftover after parsing attributes in process `syz-executor.2'.
 dev_get_iflink+0x73/0xe0 syzkaller/managers/linux-4-14/kernel/net/core/dev.c:691
 rfc2863_policy+0x163/0x1b0 syzkaller/managers/linux-4-14/kernel/net/core/link_watch.c:43
 linkwatch_do_dev+0x1b/0xf0 syzkaller/managers/linux-4-14/kernel/net/core/link_watch.c:157
 linkwatch_forget_dev+0x15c/0x1f0 syzkaller/managers/linux-4-14/kernel/net/core/link_watch.c:223
 netdev_wait_allrefs syzkaller/managers/linux-4-14/kernel/net/core/dev.c:7838 [inline]
 netdev_run_todo+0x284/0xad0 syzkaller/managers/linux-4-14/kernel/net/core/dev.c:7939
 rtnl_unlock syzkaller/managers/linux-4-14/kernel/net/core/rtnetlink.c:106 [inline]
 rtnetlink_rcv_msg+0x3cb/0xb10 syzkaller/managers/linux-4-14/kernel/net/core/rtnetlink.c:4318
 netlink_rcv_skb+0x125/0x390 syzkaller/managers/linux-4-14/kernel/net/netlink/af_netlink.c:2433
netlink: 4 bytes leftover after parsing attributes in process `syz-executor.2'.
 netlink_unicast_kernel syzkaller/managers/linux-4-14/kernel/net/netlink/af_netlink.c:1287 [inline]
 netlink_unicast+0x437/0x610 syzkaller/managers/linux-4-14/kernel/net/netlink/af_netlink.c:1313
 netlink_sendmsg+0x62e/0xb80 syzkaller/managers/linux-4-14/kernel/net/netlink/af_netlink.c:1878
 sock_sendmsg_nosec syzkaller/managers/linux-4-14/kernel/net/socket.c:646 [inline]
 sock_sendmsg+0xb5/0x100 syzkaller/managers/linux-4-14/kernel/net/socket.c:656
 ___sys_sendmsg+0x6c8/0x800 syzkaller/managers/linux-4-14/kernel/net/socket.c:2062
 __sys_sendmsg+0xa3/0x120 syzkaller/managers/linux-4-14/kernel/net/socket.c:2096
 SYSC_sendmsg syzkaller/managers/linux-4-14/kernel/net/socket.c:2107 [inline]
 SyS_sendmsg+0x27/0x40 syzkaller/managers/linux-4-14/kernel/net/socket.c:2103
 do_syscall_64+0x1d5/0x640 syzkaller/managers/linux-4-14/kernel/arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x465b09
RSP: 002b:00007fbcea20a188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000056c0b0 RCX: 0000000000465b09
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000006
RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c0b0
R13: 00007ffcd023082f R14: 00007fbcea20a300 R15: 0000000000022000

Allocated by task 26265:
 save_stack syzkaller/managers/linux-4-14/kernel/mm/kasan/kasan.c:447 [inline]
 set_track syzkaller/managers/linux-4-14/kernel/mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xeb/0x160 syzkaller/managers/linux-4-14/kernel/mm/kasan/kasan.c:551
 __do_kmalloc_node syzkaller/managers/linux-4-14/kernel/mm/slab.c:3682 [inline]
 __kmalloc_node+0x4c/0x70 syzkaller/managers/linux-4-14/kernel/mm/slab.c:3689
 kmalloc_node syzkaller/managers/linux-4-14/kernel/./include/linux/slab.h:530 [inline]
 kvmalloc_node+0x46/0xd0 syzkaller/managers/linux-4-14/kernel/mm/util.c:397
 kvmalloc syzkaller/managers/linux-4-14/kernel/./include/linux/mm.h:531 [inline]
 kvzalloc syzkaller/managers/linux-4-14/kernel/./include/linux/mm.h:539 [inline]
 alloc_netdev_mqs+0x76/0xb70 syzkaller/managers/linux-4-14/kernel/net/core/dev.c:8104
 rtnl_create_link+0x1ab/0x890 syzkaller/managers/linux-4-14/kernel/net/core/rtnetlink.c:2460
 rtnl_newlink+0xe86/0x1830 syzkaller/managers/linux-4-14/kernel/net/core/rtnetlink.c:2718
 rtnetlink_rcv_msg+0x3be/0xb10 syzkaller/managers/linux-4-14/kernel/net/core/rtnetlink.c:4316
 netlink_rcv_skb+0x125/0x390 syzkaller/managers/linux-4-14/kernel/net/netlink/af_netlink.c:2433
 netlink_unicast_kernel syzkaller/managers/linux-4-14/kernel/net/netlink/af_netlink.c:1287 [inline]
 netlink_unicast+0x437/0x610 syzkaller/managers/linux-4-14/kernel/net/netlink/af_netlink.c:1313
 netlink_sendmsg+0x62e/0xb80 syzkaller/managers/linux-4-14/kernel/net/netlink/af_netlink.c:1878
 sock_sendmsg_nosec syzkaller/managers/linux-4-14/kernel/net/socket.c:646 [inline]
 sock_sendmsg+0xb5/0x100 syzkaller/managers/linux-4-14/kernel/net/socket.c:656
 ___sys_sendmsg+0x6c8/0x800 syzkaller/managers/linux-4-14/kernel/net/socket.c:2062
 __sys_sendmsg+0xa3/0x120 syzkaller/managers/linux-4-14/kernel/net/socket.c:2096
 SYSC_sendmsg syzkaller/managers/linux-4-14/kernel/net/socket.c:2107 [inline]
 SyS_sendmsg+0x27/0x40 syzkaller/managers/linux-4-14/kernel/net/socket.c:2103
 do_syscall_64+0x1d5/0x640 syzkaller/managers/linux-4-14/kernel/arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb

Freed by task 26290:
 save_stack syzkaller/managers/linux-4-14/kernel/mm/kasan/kasan.c:447 [inline]
 set_track syzkaller/managers/linux-4-14/kernel/mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0xc3/0x1a0 syzkaller/managers/linux-4-14/kernel/mm/kasan/kasan.c:524
 __cache_free syzkaller/managers/linux-4-14/kernel/mm/slab.c:3496 [inline]
 kfree+0xc9/0x250 syzkaller/managers/linux-4-14/kernel/mm/slab.c:3815
 kvfree+0x45/0x50 syzkaller/managers/linux-4-14/kernel/mm/util.c:416
 device_release+0x15f/0x1a0 syzkaller/managers/linux-4-14/kernel/drivers/base/core.c:833
 kobject_cleanup syzkaller/managers/linux-4-14/kernel/lib/kobject.c:646 [inline]
 kobject_release syzkaller/managers/linux-4-14/kernel/lib/kobject.c:675 [inline]
 kref_put syzkaller/managers/linux-4-14/kernel/./include/linux/kref.h:70 [inline]
 kobject_put+0x251/0x550 syzkaller/managers/linux-4-14/kernel/lib/kobject.c:692
 netdev_run_todo+0x747/0xad0 syzkaller/managers/linux-4-14/kernel/net/core/dev.c:7961
 rtnl_unlock syzkaller/managers/linux-4-14/kernel/net/core/rtnetlink.c:106 [inline]
 rtnetlink_rcv_msg+0x3cb/0xb10 syzkaller/managers/linux-4-14/kernel/net/core/rtnetlink.c:4318
 netlink_rcv_skb+0x125/0x390 syzkaller/managers/linux-4-14/kernel/net/netlink/af_netlink.c:2433
 netlink_unicast_kernel syzkaller/managers/linux-4-14/kernel/net/netlink/af_netlink.c:1287 [inline]
 netlink_unicast+0x437/0x610 syzkaller/managers/linux-4-14/kernel/net/netlink/af_netlink.c:1313
 netlink_sendmsg+0x62e/0xb80 syzkaller/managers/linux-4-14/kernel/net/netlink/af_netlink.c:1878
 sock_sendmsg_nosec syzkaller/managers/linux-4-14/kernel/net/socket.c:646 [inline]
 sock_sendmsg+0xb5/0x100 syzkaller/managers/linux-4-14/kernel/net/socket.c:656
 ___sys_sendmsg+0x6c8/0x800 syzkaller/managers/linux-4-14/kernel/net/socket.c:2062
 __sys_sendmsg+0xa3/0x120 syzkaller/managers/linux-4-14/kernel/net/socket.c:2096
 SYSC_sendmsg syzkaller/managers/linux-4-14/kernel/net/socket.c:2107 [inline]
 SyS_sendmsg+0x27/0x40 syzkaller/managers/linux-4-14/kernel/net/socket.c:2103
 do_syscall_64+0x1d5/0x640 syzkaller/managers/linux-4-14/kernel/arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb

The buggy address belongs to the object at ffff8880af2ae2c0
 which belongs to the cache kmalloc-4096 of size 4096
The buggy address is located 264 bytes inside of
 4096-byte region [ffff8880af2ae2c0, ffff8880af2af2c0)
The buggy address belongs to the page:
page:ffffea0002bcab80 count:1 mapcount:0 mapping:ffff8880af2ae2c0 index:0x0 compound_mapcount: 0
flags: 0xfff00000008100(slab|head)
raw: 00fff00000008100 ffff8880af2ae2c0 0000000000000000 0000000100000001
raw: ffffea00013336a0 ffffea0001811ca0 ffff88813fe80dc0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880af2ae280: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff8880af2ae300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880af2ae380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                              ^
 ffff8880af2ae400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880af2ae480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================