BUG: KASAN: use-after-free in macvlan_dev_get_iflink+0x5f/0x70 drivers/net/macvlan.c:1138
Read of size 4 at addr ffff888026cda0d8 by task syz-executor.0/9247

CPU: 1 PID: 9247 Comm: syz-executor.0 Not tainted 5.17.0-rc8-syzkaller-00003-g56e337f2cf13 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0x8d/0x303 mm/kasan/report.c:255
 __kasan_report mm/kasan/report.c:442 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
 macvlan_dev_get_iflink+0x5f/0x70 drivers/net/macvlan.c:1138
 dev_get_iflink+0x73/0xe0 net/core/dev.c:618
 default_operstate net/core/link_watch.c:41 [inline]
 rfc2863_policy+0x233/0x2d0 net/core/link_watch.c:53
 linkwatch_do_dev+0x2a/0x150 net/core/link_watch.c:160
 linkwatch_forget_dev+0x17d/0x210 net/core/link_watch.c:249
 netdev_wait_allrefs net/core/dev.c:9832 [inline]
 netdev_run_todo+0x40b/0xaa0 net/core/dev.c:9950
 rtnl_unlock net/core/rtnetlink.c:112 [inline]
 rtnetlink_rcv_msg+0x420/0xb80 net/core/rtnetlink.c:5597
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x539/0x7e0 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2413
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2496
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fc21183b049
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:00007fc21018f168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fc21194e030 RCX: 00007fc21183b049
RDX: 0000000000000000 RSI: 0000000020000340 RDI: 0000000000000006
RBP: 00007fc21189508d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc3dc1e9bf R14: 00007fc21018f300 R15: 0000000000022000
 </TASK>

Allocated by task 9241:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:436 [inline]
 ____kasan_kmalloc mm/kasan/common.c:515 [inline]
 ____kasan_kmalloc mm/kasan/common.c:474 [inline]
 __kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:524
 kmalloc_node include/linux/slab.h:604 [inline]
 kvmalloc_node+0x3e/0x130 mm/util.c:580
 kvmalloc include/linux/slab.h:731 [inline]
 kvzalloc include/linux/slab.h:739 [inline]
 alloc_netdev_mqs+0x98/0x1070 net/core/dev.c:10163
 rtnl_create_link+0x9d7/0xc00 net/core/rtnetlink.c:3204
 __rtnl_newlink+0xf82/0x1760 net/core/rtnetlink.c:3473
 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3531
 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5596
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x539/0x7e0 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2413
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2496
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Freed by task 9248:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 kasan_set_track+0x21/0x30 mm/kasan/common.c:45
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free+0xff/0x140 mm/kasan/common.c:328
 kasan_slab_free include/linux/kasan.h:236 [inline]
 __cache_free mm/slab.c:3437 [inline]
 kfree+0xf8/0x2b0 mm/slab.c:3794
 kvfree+0x42/0x50 mm/util.c:615
 device_release+0x9f/0x240 drivers/base/core.c:2229
 kobject_cleanup lib/kobject.c:705 [inline]
 kobject_release lib/kobject.c:736 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x1c8/0x540 lib/kobject.c:753
 netdev_run_todo+0x778/0xaa0 net/core/dev.c:9973
 rtnl_unlock net/core/rtnetlink.c:112 [inline]
 rtnetlink_rcv_msg+0x420/0xb80 net/core/rtnetlink.c:5597
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x539/0x7e0 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2413
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2496
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff888026cda000
 which belongs to the cache kmalloc-cg-4k of size 4096
The buggy address is located 216 bytes inside of
 4096-byte region [ffff888026cda000, ffff888026cdb000)
The buggy address belongs to the page:
page:ffffea00009b3680 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x26cda
head:ffffea00009b3680 order:1 compound_mapcount:0
memcg:ffff888021346e81
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0000267d88 ffffea0000660988 ffff888010c43d00
raw: 0000000000000000 ffff888026cda000 0000000100000001 ffff888021346e81
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x2420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_THISNODE), pid 3126, ts 1448135163784, free_ts 1447112203278
 prep_new_page mm/page_alloc.c:2434 [inline]
 get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165
 __alloc_pages_slowpath.constprop.0+0x2eb/0x20d0 mm/page_alloc.c:4934
 __alloc_pages+0x412/0x500 mm/page_alloc.c:5402
 __alloc_pages_node include/linux/gfp.h:572 [inline]
 kmem_getpages mm/slab.c:1378 [inline]
 cache_grow_begin+0x75/0x390 mm/slab.c:2584
 cache_alloc_refill+0x27f/0x380 mm/slab.c:2957
 ____cache_alloc mm/slab.c:3040 [inline]
 ____cache_alloc mm/slab.c:3023 [inline]
 slab_alloc_node mm/slab.c:3241 [inline]
 kmem_cache_alloc_node_trace+0x49c/0x5b0 mm/slab.c:3609
 __do_kmalloc_node mm/slab.c:3631 [inline]
 __kmalloc_node+0x38/0x60 mm/slab.c:3639
 kmalloc_node include/linux/slab.h:604 [inline]
 kvmalloc_node+0x3e/0x130 mm/util.c:580
 kvmalloc include/linux/slab.h:731 [inline]
 seq_buf_alloc fs/seq_file.c:38 [inline]
 seq_read_iter+0x7f7/0x1280 fs/seq_file.c:210
 kernfs_fop_read_iter+0x514/0x6f0 fs/kernfs/file.c:241
 call_read_iter include/linux/fs.h:2068 [inline]
 new_sync_read+0x429/0x6e0 fs/read_write.c:400
 vfs_read+0x35c/0x600 fs/read_write.c:481
 ksys_read+0x12d/0x250 fs/read_write.c:619
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1352 [inline]
 free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404
 free_unref_page_prepare mm/page_alloc.c:3325 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3404
 slab_destroy mm/slab.c:1630 [inline]
 slabs_destroy+0x89/0xc0 mm/slab.c:1650
 cache_flusharray mm/slab.c:3410 [inline]
 ___cache_free+0x303/0x600 mm/slab.c:3472
 qlink_free mm/kasan/quarantine.c:157 [inline]
 qlist_free_all+0x50/0x1a0 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x97/0xb0 mm/kasan/common.c:446
 kasan_slab_alloc include/linux/kasan.h:260 [inline]
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc mm/slab.c:3315 [inline]
 kmem_cache_alloc+0x265/0x560 mm/slab.c:3499
 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138
 getname_flags+0x9a/0xe0 include/linux/audit.h:323
 user_path_at_empty+0x2b/0x60 fs/namei.c:2850
 user_path_at include/linux/namei.h:57 [inline]
 vfs_statx+0x142/0x390 fs/stat.c:221
 vfs_fstatat fs/stat.c:243 [inline]
 __do_sys_newfstatat+0x96/0x120 fs/stat.c:412
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Memory state around the buggy address:
 ffff888026cd9f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888026cda000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888026cda080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff888026cda100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888026cda180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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