==================================================================
BUG: KASAN: use-after-free in reiserfs_find_actor+0xe6/0x100 fs/reiserfs/inode.c:1633
Read of size 4 at addr ffff88805e913770 by task syz.2.1604/11788

CPU: 1 PID: 11788 Comm: syz.2.1604 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 print_address_description+0x60/0x2d0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xdf/0x130 mm/kasan/report.c:451
 reiserfs_find_actor+0xe6/0x100 fs/reiserfs/inode.c:1633
 find_inode+0x19a/0x3f0 fs/inode.c:898
 inode_insert5+0x14d/0x550 fs/inode.c:1197
 insert_inode_locked4+0x5a/0x90 fs/inode.c:1702
 reiserfs_new_inode+0x430/0x1940 fs/reiserfs/inode.c:1968
 reiserfs_create+0x3c9/0x690 fs/reiserfs/namei.c:668
 lookup_open fs/namei.c:3470 [inline]
 open_last_lookups fs/namei.c:3540 [inline]
 path_openat+0x11db/0x2fa0 fs/namei.c:3747
 do_filp_open+0x1e2/0x410 fs/namei.c:3777
 do_sys_openat2+0x150/0x4b0 fs/open.c:1255
 do_sys_open fs/open.c:1271 [inline]
 __do_sys_openat fs/open.c:1287 [inline]
 __se_sys_openat fs/open.c:1282 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1282
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc91d98ae59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc91bba2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fc91dc04180 RCX: 00007fc91d98ae59
RDX: 0000000000105042 RSI: 0000200000000340 RDI: ffffffffffffff9c
RBP: 00007fc91da20d6f R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000000b R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc91dc04218 R14: 00007fc91dc04180 R15: 00007ffefd0fbb08
 </TASK>

Allocated by task 6955:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x9c/0xd0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3225 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 kmem_cache_alloc+0x100/0x290 mm/slub.c:3238
 f2fs_kmem_cache_alloc fs/f2fs/f2fs.h:2645 [inline]
 f2fs_alloc_inode+0x16c/0x5d0 fs/f2fs/super.c:1396
 alloc_inode fs/inode.c:261 [inline]
 iget_locked+0x191/0x820 fs/inode.c:1308
 f2fs_iget+0x52/0x4a50 fs/f2fs/inode.c:505
 f2fs_fill_super+0x47fd/0x6de0 fs/f2fs/super.c:4296
 mount_bdev+0x287/0x3c0 fs/super.c:1400
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x24a/0xa40 fs/namespace.c:3034
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Last potentially related work creation:
 kasan_save_stack+0x35/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348
 __call_rcu kernel/rcu/tree.c:3011 [inline]
 call_rcu+0x189/0x950 kernel/rcu/tree.c:3091
 destroy_inode fs/inode.c:316 [inline]
 evict+0x834/0x8d0 fs/inode.c:662
 dispose_list fs/inode.c:680 [inline]
 evict_inodes+0x60c/0x6a0 fs/inode.c:734
 generic_shutdown_super+0x93/0x300 fs/super.c:454
 kill_block_super+0x7c/0xe0 fs/super.c:1427
 kill_f2fs_super+0x309/0x3c0 fs/f2fs/super.c:4568
 deactivate_locked_super+0x93/0xf0 fs/super.c:335
 cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Second to last potentially related work creation:
 kasan_save_stack+0x35/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348
 __call_rcu kernel/rcu/tree.c:3011 [inline]
 call_rcu+0x189/0x950 kernel/rcu/tree.c:3091
 destroy_inode fs/inode.c:316 [inline]
 evict+0x834/0x8d0 fs/inode.c:662
 f2fs_fill_super+0x5461/0x6de0 fs/f2fs/super.c:4474
 mount_bdev+0x287/0x3c0 fs/super.c:1400
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x24a/0xa40 fs/namespace.c:3034
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff88805e912f80
 which belongs to the cache f2fs_inode_cache of size 2304
The buggy address is located 2032 bytes inside of
 2304-byte region [ffff88805e912f80, ffff88805e913880)
The buggy address belongs to the page:
page:ffffea00017a4400 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88805e911c80 pfn:0x5e910
head:ffffea00017a4400 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff88802491e001
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff88814632cc80
raw: ffff88805e911c80 00000000800d000b 00000001ffffffff ffff88802491e001
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d2050(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 4274, ts 78689359035, free_ts 24672401878
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192
 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501
 alloc_slab_page mm/slub.c:1780 [inline]
 allocate_slab mm/slub.c:1917 [inline]
 new_slab+0xc0/0x4b0 mm/slub.c:1980
 ___slab_alloc+0x80a/0xdd0 mm/slub.c:3013
 __slab_alloc mm/slub.c:3100 [inline]
 slab_alloc_node mm/slub.c:3191 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 kmem_cache_alloc+0x195/0x290 mm/slub.c:3238
 f2fs_kmem_cache_alloc fs/f2fs/f2fs.h:2645 [inline]
 f2fs_alloc_inode+0x16c/0x5d0 fs/f2fs/super.c:1396
 alloc_inode fs/inode.c:261 [inline]
 iget_locked+0x191/0x820 fs/inode.c:1308
 f2fs_iget+0x52/0x4a50 fs/f2fs/inode.c:505
 f2fs_fill_super+0x4718/0x6de0 fs/f2fs/super.c:4288
 mount_bdev+0x287/0x3c0 fs/super.c:1400
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1530
 do_new_mount+0x24a/0xa40 fs/namespace.c:3034
 do_mount fs/namespace.c:3377 [inline]
 __do_sys_mount fs/namespace.c:3585 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317
 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396
 free_contig_range+0x96/0xf0 mm/page_alloc.c:9428
 destroy_args+0xf0/0xa00 mm/debug_vm_pgtable.c:1018
 debug_vm_pgtable+0x321/0x380 mm/debug_vm_pgtable.c:1336
 do_one_initcall+0x272/0x730 init/main.c:1316
 do_initcall_level+0x137/0x1f0 init/main.c:1389
 do_initcalls+0x4b/0x90 init/main.c:1405
 kernel_init_freeable+0x3e9/0x570 init/main.c:1629
 kernel_init+0x19/0x1b0 init/main.c:1520
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

Memory state around the buggy address:
 ffff88805e913600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805e913680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805e913700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff88805e913780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805e913800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================