loop3: detected capacity change from 0 to 1024
EXT4-fs (loop3): mounted filesystem without journal. Opts: ,errors=continue. Quota mode: none.
==================================================================
BUG: KASAN: use-after-free in ext4_xattr_rehash fs/ext4/xattr.c:3135 [inline]
BUG: KASAN: use-after-free in ext4_xattr_set_entry+0xe1f/0x3940 fs/ext4/xattr.c:1820
Read of size 4 at addr ffff88812b25e054 by task syz.3.3551/10879

CPU: 1 PID: 10879 Comm: syz.3.3551 Tainted: G        W         syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:88
 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report+0xf1/0x140 mm/kasan/report.c:444
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308
 ext4_xattr_rehash fs/ext4/xattr.c:3135 [inline]
 ext4_xattr_set_entry+0xe1f/0x3940 fs/ext4/xattr.c:1820
 ext4_xattr_block_set+0x4f8/0x2d10 fs/ext4/xattr.c:1924
 ext4_xattr_set_handle+0xbc4/0x12b0 fs/ext4/xattr.c:2407
 ext4_xattr_set+0x242/0x320 fs/ext4/xattr.c:2508
 ext4_xattr_trusted_set+0x3c/0x50 fs/ext4/xattr_trusted.c:38
 __vfs_setxattr+0x3e1/0x430 fs/xattr.c:182
 __vfs_setxattr_noperm+0x12a/0x5e0 fs/xattr.c:216
 __vfs_setxattr_locked+0x212/0x230 fs/xattr.c:277
 vfs_setxattr+0x167/0x2e0 fs/xattr.c:303
 do_setxattr fs/xattr.c:588 [inline]
 setxattr+0x36c/0x390 fs/xattr.c:611
 path_setxattr+0x147/0x290 fs/xattr.c:630
 __do_sys_lsetxattr fs/xattr.c:653 [inline]
 __se_sys_lsetxattr fs/xattr.c:649 [inline]
 __x64_sys_lsetxattr+0xc2/0xe0 fs/xattr.c:649
 x64_sys_call+0x8cc/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:190
 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: 0033:0x7efc664d5819
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:00007efc64f30028 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00007efc6674efa0 RCX: 00007efc664d5819
RDX: 0000200000000500 RSI: 0000200000000100 RDI: 0000200000000040
RBP: 00007efc6656bc91 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000fe37 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efc6674f038 R14: 00007efc6674efa0 R15: 00007fff1d3cea08
 </TASK>

The buggy address belongs to the page:
page:ffffea0004ac9780 refcount:0 mapcount:-128 mapping:0000000000000000 index:0x100 pfn:0x12b25e
flags: 0x4000000000000000(zone=1)
raw: 4000000000000000 ffffea0005011f88 ffffea0005097d88 0000000000000000
raw: 0000000000000100 0000000000000001 00000000ffffff7f 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Movable, gfp_mask 0x100cca(GFP_HIGHUSER_MOVABLE), pid 10737, ts 534243219203, free_ts 535072652592
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2611
 get_page_from_freelist+0x2d3a/0x2dc0 mm/page_alloc.c:4485
 __alloc_pages+0x1a2/0x460 mm/page_alloc.c:5822
 __alloc_pages_node include/linux/gfp.h:595 [inline]
 alloc_pages_node include/linux/gfp.h:609 [inline]
 alloc_pages include/linux/gfp.h:622 [inline]
 shmem_alloc_page mm/shmem.c:1587 [inline]
 shmem_alloc_and_acct_page+0x4a2/0x8d0 mm/shmem.c:1612
 shmem_getpage_gfp+0xfe5/0x2310 mm/shmem.c:1908
 shmem_getpage mm/shmem.c:152 [inline]
 shmem_write_begin+0xce/0x1b0 mm/shmem.c:2476
 generic_perform_write+0x2b7/0x690 mm/filemap.c:3870
 __generic_file_write_iter+0x268/0x480 mm/filemap.c:3998
 generic_file_write_iter+0xa9/0x1d0 mm/filemap.c:4030
 do_iter_readv_writev+0x478/0x5f0 fs/read_write.c:-1
 do_iter_write+0x1fa/0x7b0 fs/read_write.c:855
 vfs_writev+0x2df/0x570 fs/read_write.c:928
 do_pwritev fs/read_write.c:1025 [inline]
 __do_sys_pwritev2 fs/read_write.c:1084 [inline]
 __se_sys_pwritev2+0x1af/0x2b0 fs/read_write.c:1075
 __x64_sys_pwritev2+0xbf/0xd0 fs/read_write.c:1075
 x64_sys_call+0x346/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:329
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1472 [inline]
 free_pcp_prepare mm/page_alloc.c:1544 [inline]
 free_unref_page_prepare+0x542/0x550 mm/page_alloc.c:3534
 free_unref_page_list+0x13a/0x9d0 mm/page_alloc.c:3671
 release_pages+0x1006/0x1060 mm/swap.c:1015
 __pagevec_release+0x71/0xe0 mm/swap.c:1035
 pagevec_release include/linux/pagevec.h:81 [inline]
 shmem_undo_range+0x595/0x1470 mm/shmem.c:965
 shmem_truncate_range mm/shmem.c:1064 [inline]
 shmem_evict_inode+0x21a/0xa10 mm/shmem.c:1146
 evict+0x4c9/0x8d0 fs/inode.c:650
 iput_final fs/inode.c:1779 [inline]
 iput+0x635/0x7c0 fs/inode.c:1805
 do_unlinkat+0x380/0x6d0 fs/namei.c:4363
 __do_sys_unlink fs/namei.c:4404 [inline]
 __se_sys_unlink fs/namei.c:4402 [inline]
 __x64_sys_unlink+0x49/0x50 fs/namei.c:4402
 x64_sys_call+0x878/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:88
 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

Memory state around the buggy address:
 ffff88812b25df00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88812b25df80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88812b25e000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                 ^
 ffff88812b25e080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88812b25e100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================