==================================================================
BUG: KASAN: slab-out-of-bounds in dns_resolver_preparse+0xcb3/0xd30 net/dns_resolver/dns_key.c:127
Read of size 1 at addr ffff888145ad684c by task syz-executor.3/8547

CPU: 0 PID: 8547 Comm: syz-executor.3 Not tainted 6.7.0-rc6-syzkaller-00303-g3f82f1c3a036 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0x163/0x540 mm/kasan/report.c:475
 kasan_report+0x142/0x170 mm/kasan/report.c:588
 dns_resolver_preparse+0xcb3/0xd30 net/dns_resolver/dns_key.c:127
 __key_create_or_update+0x47f/0xc40 security/keys/key.c:842
 key_create_or_update+0x42/0x60 security/keys/key.c:1007
 __do_sys_add_key security/keys/keyctl.c:134 [inline]
 __se_sys_add_key+0x33f/0x480 security/keys/keyctl.c:74
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x45/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7fe0dfe7cce9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe0e0bf20c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000f8
RAX: ffffffffffffffda RBX: 00007fe0dff9bf80 RCX: 00007fe0dfe7cce9
RDX: 0000000020000080 RSI: 0000000000000000 RDI: 00000000200003c0
RBP: 00007fe0dfec947a R08: 00000000005bfc4d R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fe0dff9bf80 R15: 00007ffff70803d8
 </TASK>

Allocated by task 8547:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:198 [inline]
 __do_kmalloc_node mm/slab_common.c:1007 [inline]
 __kmalloc_node+0xb3/0x190 mm/slab_common.c:1014
 kmalloc_node include/linux/slab.h:620 [inline]
 kvmalloc_node+0x72/0x180 mm/util.c:617
 kvmalloc include/linux/slab.h:738 [inline]
 __do_sys_add_key security/keys/keyctl.c:116 [inline]
 __se_sys_add_key+0x270/0x480 security/keys/keyctl.c:74
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x45/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

The buggy address belongs to the object at ffff888145ad6848
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes to the right of
 allocated 4-byte region [ffff888145ad6848, ffff888145ad684c)

The buggy address belongs to the physical page:
page:ffffea000516b580 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x145ad6
flags: 0x57ff00000000800(slab|node=1|zone=2|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 057ff00000000800 ffff888012c41280 ffffea000514ab00 dead000000000002
raw: 0000000000000000 0000000080660066 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 1, tgid 1 (swapper/0), ts 5713866731, free_ts 0
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1544 [inline]
 get_page_from_freelist+0x33ea/0x3570 mm/page_alloc.c:3312
 __alloc_pages+0x255/0x680 mm/page_alloc.c:4568
 alloc_pages_mpol+0x3de/0x640 mm/mempolicy.c:2133
 alloc_slab_page+0x6a/0x170 mm/slub.c:1870
 allocate_slab mm/slub.c:2017 [inline]
 new_slab+0x84/0x2f0 mm/slub.c:2070
 ___slab_alloc+0xc8a/0x1330 mm/slub.c:3223
 __slab_alloc mm/slub.c:3322 [inline]
 __slab_alloc_node mm/slub.c:3375 [inline]
 slab_alloc_node mm/slub.c:3468 [inline]
 __kmem_cache_alloc_node+0x21d/0x300 mm/slub.c:3517
 __do_kmalloc_node mm/slab_common.c:1006 [inline]
 __kmalloc_node_track_caller+0xa0/0x190 mm/slab_common.c:1027
 kstrdup+0x3a/0x70 mm/util.c:62
 __kernfs_new_node+0x9d/0x870 fs/kernfs/dir.c:611
 kernfs_new_node+0x99/0x170 fs/kernfs/dir.c:679
 kernfs_create_link+0xa5/0x1f0 fs/kernfs/symlink.c:39
 sysfs_do_create_link_sd+0x85/0x110 fs/sysfs/symlink.c:44
 driver_sysfs_add+0x8c/0x1f0 drivers/base/dd.c:441
 really_probe+0x149/0xc30 drivers/base/dd.c:645
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888145ad6700: fc fa fc fc fc fc fa fc fc fc fc fa fc fc fc fc
 ffff888145ad6780: 05 fc fc fc fc 00 fc fc fc fc 00 fc fc fc fc 00
>ffff888145ad6800: fc fc fc fc fb fc fc fc fc 04 fc fc fc fc fa fc
                                              ^
 ffff888145ad6880: fc fc fc fa fc fc fc fc 07 fc fc fc fc fa fc fc
 ffff888145ad6900: fc fc fa fc fc fc fc fa fc fc fc fc fa fc fc fc
==================================================================