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BUG: KASAN: slab-use-after-free in check_igot_inode fs/ext4/inode.c:-1 [inline]
BUG: KASAN: slab-use-after-free in __ext4_iget+0x2c0/0x3f40 fs/ext4/inode.c:4850
Read of size 8 at addr ffff888078ab2050 by task syz.3.6676/20327

CPU: 1 PID: 20327 Comm: syz.3.6676 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0xa8/0x210 mm/kasan/report.c:468
 kasan_report+0x117/0x150 mm/kasan/report.c:581
 check_igot_inode fs/ext4/inode.c:-1 [inline]
 __ext4_iget+0x2c0/0x3f40 fs/ext4/inode.c:4850
 __ext4_fill_super fs/ext4/super.c:5517 [inline]
 ext4_fill_super+0x503a/0x67b0 fs/ext4/super.c:5744
 get_tree_bdev+0x3f3/0x520 fs/super.c:1591
 vfs_get_tree+0x8c/0x280 fs/super.c:1764
 do_new_mount+0x24b/0xa40 fs/namespace.c:3386
 do_mount fs/namespace.c:3726 [inline]
 __do_sys_mount fs/namespace.c:3935 [inline]
 __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fb036f9e04a
Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007fb037f10e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fb037f10ee0 RCX: 00007fb036f9e04a
RDX: 0000200000000080 RSI: 0000200000000000 RDI: 00007fb037f10ea0
RBP: 0000200000000080 R08: 00007fb037f10ee0 R09: 000000000200801f
R10: 000000000200801f R11: 0000000000000246 R12: 0000200000000000
R13: 00007fb037f10ea0 R14: 00000000000004ec R15: 00002000000000c0
 </TASK>

Allocated by task 17947:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767
 slab_alloc_node mm/slub.c:3495 [inline]
 slab_alloc mm/slub.c:3503 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3510 [inline]
 kmem_cache_alloc_lru+0x111/0x2d0 mm/slub.c:3526
 alloc_inode_sb include/linux/fs.h:2946 [inline]
 reiserfs_alloc_inode+0x2a/0xc0 fs/reiserfs/super.c:642
 alloc_inode fs/inode.c:261 [inline]
 iget5_locked+0xa2/0x260 fs/inode.c:1314
 reiserfs_fill_super+0x11d7/0x23b0 fs/reiserfs/super.c:2053
 mount_bdev+0x221/0x2d0 fs/super.c:1643
 legacy_get_tree+0xea/0x180 fs/fs_context.c:662
 vfs_get_tree+0x8c/0x280 fs/super.c:1764
 do_new_mount+0x24b/0xa40 fs/namespace.c:3386
 do_mount fs/namespace.c:3726 [inline]
 __do_sys_mount fs/namespace.c:3935 [inline]
 __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Last potentially related work creation:
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46
 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492
 __call_rcu_common kernel/rcu/tree.c:2721 [inline]
 call_rcu+0x153/0x950 kernel/rcu/tree.c:2837
 destroy_inode fs/inode.c:316 [inline]
 evict+0x835/0x8d0 fs/inode.c:720
 reiserfs_fill_super+0x1479/0x23b0 fs/reiserfs/super.c:2078
 mount_bdev+0x221/0x2d0 fs/super.c:1643
 legacy_get_tree+0xea/0x180 fs/fs_context.c:662
 vfs_get_tree+0x8c/0x280 fs/super.c:1764
 do_new_mount+0x24b/0xa40 fs/namespace.c:3386
 do_mount fs/namespace.c:3726 [inline]
 __do_sys_mount fs/namespace.c:3935 [inline]
 __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff888078ab1a80
 which belongs to the cache reiser_inode_cache of size 1568
The buggy address is located 1488 bytes inside of
 freed 1568-byte region [ffff888078ab1a80, ffff888078ab20a0)

The buggy address belongs to the physical page:
page:ffffea0001e2ac00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888078ab27c0 pfn:0x78ab0
head:ffffea0001e2ac00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff888025c54801
flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888141eb2dc0 dead000000000122 0000000000000000
raw: ffff888078ab27c0 000000008013000e 00000001ffffffff ffff888025c54801
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d20d0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 7359, tgid 7358 (syz.2.918), ts 140325779226, free_ts 91916872468
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581
 prep_new_page mm/page_alloc.c:1588 [inline]
 get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220
 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4500
 alloc_slab_page+0x5d/0x160 mm/slub.c:1881
 allocate_slab mm/slub.c:2028 [inline]
 new_slab+0x87/0x2d0 mm/slub.c:2081
 ___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253
 __slab_alloc mm/slub.c:3339 [inline]
 __slab_alloc_node mm/slub.c:3392 [inline]
 slab_alloc_node mm/slub.c:3485 [inline]
 slab_alloc mm/slub.c:3503 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3510 [inline]
 kmem_cache_alloc_lru+0x1aa/0x2d0 mm/slub.c:3526
 alloc_inode_sb include/linux/fs.h:2946 [inline]
 reiserfs_alloc_inode+0x2a/0xc0 fs/reiserfs/super.c:642
 alloc_inode fs/inode.c:261 [inline]
 iget5_locked+0xa2/0x260 fs/inode.c:1314
 reiserfs_fill_super+0x11d7/0x23b0 fs/reiserfs/super.c:2053
 mount_bdev+0x221/0x2d0 fs/super.c:1643
 legacy_get_tree+0xea/0x180 fs/fs_context.c:662
 vfs_get_tree+0x8c/0x280 fs/super.c:1764
 do_new_mount+0x24b/0xa40 fs/namespace.c:3386
 do_mount fs/namespace.c:3726 [inline]
 __do_sys_mount fs/namespace.c:3935 [inline]
 __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1181 [inline]
 free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365
 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458
 __slab_free+0x35a/0x400 mm/slub.c:3736
 qlink_free mm/kasan/quarantine.c:166 [inline]
 qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185
 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767
 slab_alloc_node mm/slub.c:3495 [inline]
 slab_alloc mm/slub.c:3503 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3510 [inline]
 kmem_cache_alloc+0x11a/0x2d0 mm/slub.c:3519
 anon_vma_chain_alloc mm/rmap.c:142 [inline]
 anon_vma_fork+0x1f1/0x500 mm/rmap.c:365
 dup_mmap kernel/fork.c:733 [inline]
 dup_mm kernel/fork.c:1693 [inline]
 copy_mm+0xde9/0x1d80 kernel/fork.c:1742
 copy_process+0x16f7/0x3d80 kernel/fork.c:2507
 kernel_clone+0x24b/0x8a0 kernel/fork.c:2915
 __do_sys_clone kernel/fork.c:3058 [inline]
 __se_sys_clone kernel/fork.c:3042 [inline]
 __x64_sys_clone+0x1b7/0x230 kernel/fork.c:3042
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff888078ab1f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888078ab1f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888078ab2000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff888078ab2080: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888078ab2100: fc fc fc fc 00 00 00 00 00 00 00 00 00 00 00 00
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