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BUG: KASAN: use-after-free in strlen+0x79/0x90 lib/string.c:565
Read of size 1 at addr ffff88801f692de8 by task syz-executor.4/8372

CPU: 0 PID: 8372 Comm: syz-executor.4 Not tainted 5.11.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x9a/0xcc lib/dump_stack.c:120
 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:230
 __kasan_report mm/kasan/report.c:396 [inline]
 kasan_report.cold+0x79/0xd5 mm/kasan/report.c:413
 strlen+0x79/0x90 lib/string.c:565
 strlen include/linux/string.h:322 [inline]
 nla_strcmp+0x18/0xe0 lib/nlattr.c:826
 nft_table_lookup+0xaf/0x1b0 net/netfilter/nf_tables_api.c:520
 nft_ctx_init_from_setattr net/netfilter/nf_tables_api.c:3613 [inline]
 nf_tables_getset+0x13a/0x660 net/netfilter/nf_tables_api.c:4028
 nfnetlink_rcv_msg+0x424/0xc90 net/netfilter/nfnetlink.c:241
 netlink_rcv_skb+0x118/0x370 net/netlink/af_netlink.c:2502
 nfnetlink_rcv+0x143/0x340 net/netfilter/nfnetlink.c:600
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x42e/0x700 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0x70e/0xbe0 net/netlink/af_netlink.c:1927
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xab/0xe0 net/socket.c:672
 ____sys_sendmsg+0x5bf/0x7a0 net/socket.c:2345
 ___sys_sendmsg+0xd3/0x150 net/socket.c:2399
 __sys_sendmsg+0xb2/0x140 net/socket.c:2432
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x4665f9
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0647d23188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665f9
RDX: 0000000000000000 RSI: 0000000020000d80 RDI: 0000000000000004
RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80
R13: 00007ffd7620b60f R14: 00007f0647d23300 R15: 0000000000022000

Allocated by task 8372:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:401 [inline]
 ____kasan_kmalloc.constprop.0+0x82/0xa0 mm/kasan/common.c:429
 kmalloc include/linux/slab.h:557 [inline]
 nla_strdup+0x93/0x130 lib/nlattr.c:769
 nf_tables_newtable+0x8b8/0x19f0 net/netfilter/nf_tables_api.c:1042
 nfnetlink_rcv_batch+0x68c/0x2050 net/netfilter/nfnetlink.c:456
 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:580 [inline]
 nfnetlink_rcv+0x2bc/0x340 net/netfilter/nfnetlink.c:598
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x42e/0x700 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0x70e/0xbe0 net/netlink/af_netlink.c:1927
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xab/0xe0 net/socket.c:672
 ____sys_sendmsg+0x5bf/0x7a0 net/socket.c:2345
 ___sys_sendmsg+0xd3/0x150 net/socket.c:2399
 __sys_sendmsg+0xb2/0x140 net/socket.c:2432
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 8361:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:356
 ____kasan_slab_free+0xe1/0x110 mm/kasan/common.c:362
 kasan_slab_free include/linux/kasan.h:192 [inline]
 slab_free_hook mm/slub.c:1547 [inline]
 slab_free_freelist_hook+0x5d/0x150 mm/slub.c:1580
 slab_free mm/slub.c:3143 [inline]
 kfree+0xdb/0x3b0 mm/slub.c:4139
 nf_tables_table_destroy+0xba/0x180 net/netfilter/nf_tables_api.c:1238
 __nft_release_table+0xa04/0xe60 net/netfilter/nf_tables_api.c:9073
 nft_rcv_nl_event+0x3ac/0x510 net/netfilter/nf_tables_api.c:9113
 notifier_call_chain+0x94/0x170 kernel/notifier.c:83
 blocking_notifier_call_chain kernel/notifier.c:337 [inline]
 blocking_notifier_call_chain+0x5d/0x80 kernel/notifier.c:325
 netlink_release+0xa1f/0x17d0 net/netlink/af_netlink.c:783
 __sock_release+0xbb/0x270 net/socket.c:597
 sock_close+0xf/0x20 net/socket.c:1256
 __fput+0x204/0x870 fs/file_table.c:280
 task_work_run+0xc0/0x160 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x249/0x250 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff88801f692de8
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes inside of
 8-byte region [ffff88801f692de8, ffff88801f692df0)
The buggy address belongs to the page:
page:00000000cc8bfb2c refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88801f692820 pfn:0x1f692
flags: 0xfff00000000200(slab)
raw: 00fff00000000200 ffffea0000574040 0000001800000018 ffff88800f441c80
raw: ffff88801f692820 000000008066005a 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 4059, ts 7815528972
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x144/0x1c0 mm/page_alloc.c:2297
 prep_new_page mm/page_alloc.c:2306 [inline]
 get_page_from_freelist+0x1c6e/0x3f80 mm/page_alloc.c:3945
 __alloc_pages_nodemask+0x2d6/0x730 mm/page_alloc.c:4995
 alloc_pages include/linux/gfp.h:547 [inline]
 alloc_slab_page mm/slub.c:1618 [inline]
 allocate_slab+0x2b6/0x4a0 mm/slub.c:1758
 new_slab mm/slub.c:1821 [inline]
 new_slab_objects mm/slub.c:2578 [inline]
 ___slab_alloc+0x476/0x790 mm/slub.c:2741
 __slab_alloc.constprop.0+0x95/0xe0 mm/slub.c:2781
 slab_alloc_node mm/slub.c:2857 [inline]
 slab_alloc mm/slub.c:2900 [inline]
 __kmalloc+0x34a/0x3e0 mm/slub.c:3981
 kmalloc include/linux/slab.h:557 [inline]
 kzalloc include/linux/slab.h:682 [inline]
 lsm_cred_alloc security/security.c:534 [inline]
 security_prepare_creds+0xbf/0x140 security/security.c:1633
 prepare_creds+0x3cc/0x590 kernel/cred.c:285
 prepare_exec_creds+0x8/0x240 kernel/cred.c:304
 prepare_bprm_creds fs/exec.c:1465 [inline]
 bprm_execve+0xba/0x1520 fs/exec.c:1794
 kernel_execve+0x2c2/0x3e0 fs/exec.c:1969
 call_usermodehelper_exec_async+0x2c1/0x500 kernel/umh.c:110
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1271 [inline]
 free_pcp_prepare+0x2cb/0x410 mm/page_alloc.c:1306
 free_unref_page_prepare mm/page_alloc.c:3200 [inline]
 free_unref_page+0x12/0x1b0 mm/page_alloc.c:3248
 __vunmap+0x59e/0x940 mm/vmalloc.c:2286
 free_work+0x4b/0x70 mm/vmalloc.c:67
 process_one_work+0x84c/0x13b0 kernel/workqueue.c:2275
 worker_thread+0x598/0xf80 kernel/workqueue.c:2421
 kthread+0x36f/0x450 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Memory state around the buggy address:
 ffff88801f692c80: 00 fc fc fc fc fb fc fc fc fc fa fc fc fc fc fa
 ffff88801f692d00: fc fc fc fc fa fc fc fc fc fa fc fc fc fc 00 fc
>ffff88801f692d80: fc fc fc 00 fc fc fc fc 00 fc fc fc fc fa fc fc
                                                          ^
 ffff88801f692e00: fc fc fa fc fc fc fc fa fc fc fc fc fb fc fc fc
 ffff88801f692e80: fc fa fc fc fc fc fb fc fc fc fc fb fc fc fc fc
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