EXT4-fs (loop2): mounted filesystem without journal. Opts: ,errors=continue. Quota mode: none.
netlink: 88 bytes leftover after parsing attributes in process `syz.2.1453'.
netlink: 48 bytes leftover after parsing attributes in process `syz.2.1453'.
==================================================================
BUG: KASAN: use-after-free in ext4_xattr_set_entry+0x1c3e/0x37d0 fs/ext4/xattr.c:1727
Read of size 15400 at addr ffff8881378867e0 by task syz.2.1453/6076

CPU: 0 PID: 6076 Comm: syz.2.1453 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:88
 dump_stack_lvl+0xee/0x150 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
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x280/0x290 mm/kasan/generic.c:189
 memmove+0x2d/0x70 mm/kasan/shadow.c:54
 ext4_xattr_set_entry+0x1c3e/0x37d0 fs/ext4/xattr.c:1727
 ext4_xattr_block_set+0x4fc/0x2cb0 fs/ext4/xattr.c:1936
 ext4_xattr_set_handle+0xbd5/0x12b0 fs/ext4/xattr.c:2422
 ext4_xattr_set+0x22a/0x320 fs/ext4/xattr.c:2523
 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+0x168/0x2f0 fs/xattr.c:303
 do_setxattr fs/xattr.c:588 [inline]
 setxattr+0x2da/0x300 fs/xattr.c:611
 path_setxattr+0x142/0x280 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: 0033:0x7faf307256c9
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:00007faf2f16c038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00007faf3097c090 RCX: 00007faf307256c9
RDX: 0000200000000440 RSI: 00002000000000c0 RDI: 0000200000000100
RBP: 00007faf307a7f91 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000fe37 R11: 0000000000000246 R12: 0000000000000000
R13: 00007faf3097c128 R14: 00007faf3097c090 R15: 00007fffa4968018
 </TASK>

The buggy address belongs to the page:
page:ffffea0004de2180 refcount:2 mapcount:0 mapping:ffff88810930a4d8 index:0x1c pfn:0x137886
memcg:ffff88810e94a280
aops:def_blk_aops ino:700002
flags: 0x400000000000203a(referenced|dirty|lru|active|private|zone=1)
raw: 400000000000203a ffffea00046c1588 ffffea0004eed4c8 ffff88810930a4d8
raw: 000000000000001c ffff888129a432a0 00000002ffffffff ffff88810e94a280
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Movable, gfp_mask 0x108c48(GFP_NOFS|__GFP_NOFAIL|__GFP_HARDWALL|__GFP_MOVABLE), pid 6076, ts 263243875570, free_ts 263225351881
 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+0x2cc5/0x2d50 mm/page_alloc.c:4485
 __alloc_pages+0x18f/0x440 mm/page_alloc.c:5808
 __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]
 __page_cache_alloc include/linux/pagemap.h:305 [inline]
 pagecache_get_page+0xa82/0xda0 mm/filemap.c:1955
 find_or_create_page include/linux/pagemap.h:418 [inline]
 grow_dev_page fs/buffer.c:949 [inline]
 grow_buffers fs/buffer.c:1014 [inline]
 __getblk_slow fs/buffer.c:1041 [inline]
 __getblk_gfp+0x238/0x7d0 fs/buffer.c:1336
 sb_getblk include/linux/buffer_head.h:361 [inline]
 ext4_xattr_block_set+0x198c/0x2cb0 fs/ext4/xattr.c:2117
 ext4_xattr_set_handle+0xbd5/0x12b0 fs/ext4/xattr.c:2422
 ext4_xattr_set+0x22a/0x320 fs/ext4/xattr.c:2523
 ext4_xattr_user_set+0xc4/0xf0 fs/ext4/xattr_user.c:41
 __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+0x168/0x2f0 fs/xattr.c:303
 do_setxattr fs/xattr.c:588 [inline]
 setxattr+0x2da/0x300 fs/xattr.c:611
 path_setxattr+0x142/0x280 fs/xattr.c:630
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+0x134/0x9d0 mm/page_alloc.c:3671
 release_pages+0xfda/0x1030 mm/swap.c:1014
 free_pages_and_swap_cache+0x86/0xa0 mm/swap_state.c:320
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:240 [inline]
 tlb_flush_mmu mm/mmu_gather.c:247 [inline]
 tlb_finish_mmu+0x175/0x300 mm/mmu_gather.c:338
 unmap_region+0x315/0x360 mm/mmap.c:2692
 __do_munmap+0xa0e/0xfe0 mm/mmap.c:2925
 __vm_munmap+0x15b/0x2a0 mm/mmap.c:2978
 __do_sys_munmap mm/mmap.c:3004 [inline]
 __se_sys_munmap mm/mmap.c:3000 [inline]
 __x64_sys_munmap+0x6b/0x80 mm/mmap.c:3000
 x64_sys_call+0xc9/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:12
 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:
 ffff888137886f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888137886f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888137887000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff888137887080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888137887100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================