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BUG: KASAN: slab-use-after-free in smk_access+0xae/0x4e0 security/smack/smack_access.c:147
Read of size 8 at addr ffff88805bb0fe80 by task syz.0.20/5368

CPU: 1 UID: 0 PID: 5368 Comm: syz.0.20 Not tainted 6.11.0-syzkaller-08829-gaf9c191ac2a0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 smk_access+0xae/0x4e0 security/smack/smack_access.c:147
 smack_watch_key+0x2f4/0x3a0 security/smack/smack_lsm.c:4656
 security_watch_key+0x86/0x250 security/security.c:4448
 keyctl_watch_key+0x2b7/0x480 security/keys/keyctl.c:1813
 __do_sys_keyctl security/keys/keyctl.c:2021 [inline]
 __se_sys_keyctl+0x106/0xa50 security/keys/keyctl.c:1874
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6fff57def9
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f700029a038 EFLAGS: 00000246 ORIG_RAX: 00000000000000fa
RAX: ffffffffffffffda RBX: 00007f6fff736058 RCX: 00007f6fff57def9
RDX: 000000000000000c RSI: 000000002528b274 RDI: 0000000000000020
RBP: 00007f6fff5f0b76 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f6fff736058 R15: 00007ffdfa5358a8
 </TASK>

Allocated by task 5368:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:257 [inline]
 __do_kmalloc_node mm/slub.c:4265 [inline]
 __kmalloc_node_track_caller_noprof+0x225/0x440 mm/slub.c:4284
 memdup_user+0x2b/0xc0 mm/util.c:226
 strndup_user+0x68/0xc0 mm/util.c:285
 __do_sys_add_key security/keys/keyctl.c:96 [inline]
 __se_sys_add_key+0x1b0/0x490 security/keys/keyctl.c:74
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5368:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:2343 [inline]
 slab_free mm/slub.c:4580 [inline]
 kfree+0x1a0/0x440 mm/slub.c:4728
 __do_sys_add_key security/keys/keyctl.c:149 [inline]
 __se_sys_add_key+0x3be/0x490 security/keys/keyctl.c:74
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88805bb0fe80
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes inside of
 freed 8-byte region [ffff88805bb0fe80, ffff88805bb0fe88)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5bb0f
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801ac41500 dead000000000122 0000000000000000
raw: 0000000000000000 0000000080800080 00000001f5000000 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 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5218, tgid 5218 (syz-executor), ts 81115255785, free_ts 81115166253
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1545 [inline]
 get_page_from_freelist+0x3039/0x3180 mm/page_alloc.c:3457
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4733
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 alloc_slab_page+0x6a/0x120 mm/slub.c:2413
 allocate_slab+0x5a/0x2f0 mm/slub.c:2579
 new_slab mm/slub.c:2632 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3819
 __slab_alloc+0x58/0xa0 mm/slub.c:3909
 __slab_alloc_node mm/slub.c:3962 [inline]
 slab_alloc_node mm/slub.c:4123 [inline]
 __do_kmalloc_node mm/slub.c:4264 [inline]
 __kmalloc_node_noprof+0x286/0x440 mm/slub.c:4271
 kmalloc_node_noprof include/linux/slab.h:905 [inline]
 __vmalloc_area_node mm/vmalloc.c:3624 [inline]
 __vmalloc_node_range_noprof+0x5c3/0x13f0 mm/vmalloc.c:3828
 __vmalloc_node_noprof mm/vmalloc.c:3893 [inline]
 vzalloc_noprof+0x79/0x90 mm/vmalloc.c:3966
 alloc_counters+0xd7/0x740 net/ipv4/netfilter/ip_tables.c:799
 copy_entries_to_user net/ipv6/netfilter/ip6_tables.c:837 [inline]
 get_entries net/ipv6/netfilter/ip6_tables.c:1039 [inline]
 do_ip6t_get_ctl+0xecc/0x1820 net/ipv6/netfilter/ip6_tables.c:1677
 nf_getsockopt+0x299/0x2c0 net/netfilter/nf_sockopt.c:116
 ipv6_getsockopt+0x23e/0x360 net/ipv6/ipv6_sockglue.c:1493
 tcp_getsockopt+0x163/0x1c0 net/ipv4/tcp.c:4670
page last free pid 5218 tgid 5218 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1108 [inline]
 free_unref_page+0xcd0/0xf00 mm/page_alloc.c:2638
 vfree+0x186/0x2e0 mm/vmalloc.c:3361
 copy_entries_to_user net/ipv6/netfilter/ip6_tables.c:882 [inline]
 get_entries net/ipv6/netfilter/ip6_tables.c:1039 [inline]
 do_ip6t_get_ctl+0x11eb/0x1820 net/ipv6/netfilter/ip6_tables.c:1677
 nf_getsockopt+0x299/0x2c0 net/netfilter/nf_sockopt.c:116
 ipv6_getsockopt+0x23e/0x360 net/ipv6/ipv6_sockglue.c:1493
 tcp_getsockopt+0x163/0x1c0 net/ipv4/tcp.c:4670
 do_sock_getsockopt+0x3c4/0x7e0 net/socket.c:2392
 __sys_getsockopt+0x26b/0x330 net/socket.c:2421
 __do_sys_getsockopt net/socket.c:2431 [inline]
 __se_sys_getsockopt net/socket.c:2428 [inline]
 __x64_sys_getsockopt+0xb5/0xd0 net/socket.c:2428
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88805bb0fd80: 06 fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc
 ffff88805bb0fe00: 05 fc fc fc 00 fc fc fc 05 fc fc fc 00 fc fc fc
>ffff88805bb0fe80: fa fc fc fc 05 fc fc fc 00 fc fc fc fc fc fc fc
                   ^
 ffff88805bb0ff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88805bb0ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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