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BUG: KASAN: out-of-bounds in ext4_xattr_set_entry+0x92b/0x1ed0 fs/ext4/xattr.c:1763
Read of size 18446744073709551600 at addr ffff888040843d24 by task syz.0.0/5319

CPU: 0 UID: 0 PID: 5319 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x264/0x2c0 mm/kasan/generic.c:200
 __asan_memmove+0x29/0x70 mm/kasan/shadow.c:94
 ext4_xattr_set_entry+0x92b/0x1ed0 fs/ext4/xattr.c:1763
 ext4_xattr_ibody_set+0x262/0x710 fs/ext4/xattr.c:2275
 ext4_destroy_inline_data_nolock+0x23a/0x5f0 fs/ext4/inline.c:472
 ext4_convert_inline_data_nolock+0x208/0x980 fs/ext4/inline.c:1123
 ext4_convert_inline_data+0x484/0x5c0 fs/ext4/inline.c:1994
 ext4_page_mkwrite+0x244/0x1140 fs/ext4/inode.c:6809
 do_page_mkwrite+0x147/0x310 mm/memory.c:3684
 wp_page_shared mm/memory.c:4085 [inline]
 do_wp_page+0x1973/0x4c70 mm/memory.c:4304
 handle_pte_fault mm/memory.c:6395 [inline]
 __handle_mm_fault mm/memory.c:6517 [inline]
 handle_mm_fault+0x1490/0x3080 mm/memory.c:6686
 do_user_addr_fault+0xa4d/0x1340 arch/x86/mm/fault.c:1343
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7f30fdb6d435
Code: fe 28 6f 06 48 83 fa 40 0f 87 a7 00 00 00 62 e1 fe 28 6f 4c 16 ff 62 e1 fe 28 7f 07 62 e1 fe 28 7f 4c 17 ff c3 8b 0e 8b 34 16 <89> 0f 89 34 17 c3 0f 1f 44 00 00 83 fa 10 73 21 83 fa 08 73 36 48
RSP: 002b:00007ffc78691938 EFLAGS: 00010246
RAX: 0000200000000400 RBX: 0000000000000004 RCX: 000000000073666a
RDX: 0000000000000000 RSI: 000000000073666a RDI: 0000200000000400
RBP: fffffffffffffffe R08: 00007f30fd9ff030 R09: 0000000000000001
R10: 7ffffffffffffffb R11: 0000000000000009 R12: 00007ffc78691a60
R13: 00007f30fde15fac R14: 00000000000194ff R15: 00007f30fde15fa0
 </TASK>

The buggy address belongs to the physical page:
page: refcount:3 mapcount:0 mapping:ffff88801cc25940 index:0x4 pfn:0x40843
memcg:ffff888039f84100
aops:def_blk_aops ino:700000 dentry name(?):""
flags: 0x4fff18000004214(referenced|dirty|workingset|private|node=1|zone=1|lastcpupid=0x7ff)
raw: 04fff18000004214 0000000000000000 dead000000000122 ffff88801cc25940
raw: 0000000000000004 ffff888043f3f540 00000003ffffffff ffff888039f84100
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Movable, gfp_mask 0x148c48(GFP_NOFS|__GFP_MOVABLE|__GFP_NOFAIL|__GFP_COMP|__GFP_HARDWALL), pid 5319, tgid 5319 (syz.0.0), ts 104394864101, free_ts 104364010740
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0x21fa/0x2270 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304
 alloc_pages_mpol+0x212/0x380 mm/mempolicy.c:2490
 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline]
 alloc_pages_noprof+0xac/0x2a0 mm/mempolicy.c:2581
 folio_alloc_noprof+0x1e/0x30 mm/mempolicy.c:2591
 filemap_alloc_folio_noprof+0x111/0x470 mm/filemap.c:1013
 __filemap_get_folio_mpol+0x402/0x1000 mm/filemap.c:2012
 __filemap_get_folio include/linux/pagemap.h:761 [inline]
 grow_dev_folio fs/buffer.c:960 [inline]
 grow_buffers fs/buffer.c:1026 [inline]
 __getblk_slow fs/buffer.c:1044 [inline]
 bdev_getblk+0x1f4/0x6e0 fs/buffer.c:1439
 __getblk include/linux/buffer_head.h:382 [inline]
 sb_getblk include/linux/buffer_head.h:388 [inline]
 __ext4_get_inode_loc+0x56c/0xf40 fs/ext4/inode.c:4891
 ext4_get_inode_loc fs/ext4/inode.c:5019 [inline]
 ext4_reserve_inode_write+0x18b/0x360 fs/ext4/inode.c:6424
 __ext4_mark_inode_dirty+0x13e/0x700 fs/ext4/inode.c:6602
 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6639
 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2709
 generic_update_time fs/inode.c:2257 [inline]
 file_update_time_flags+0x3ee/0x4a0 fs/inode.c:2487
 ext4_page_mkwrite+0x224/0x1140 fs/ext4/inode.c:6805
page last free pid 5320 tgid 5319 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 free_unref_folios+0xd84/0x14a0 mm/page_alloc.c:3011
 folio_batch_move_lru+0x877/0xa60 mm/swap.c:211
 lru_add_drain_cpu+0xbc/0x750 mm/swap.c:699
 lru_add_drain+0x121/0x3e0 mm/swap.c:788
 __folio_batch_release+0x48/0x90 mm/swap.c:1114
 folio_batch_release include/linux/folio_batch.h:101 [inline]
 writeback_get_folio mm/page-writeback.c:2426 [inline]
 writeback_iter+0x73c/0x1320 mm/page-writeback.c:2529
 blkdev_writepages+0x107/0x1b0 block/fops.c:484
 do_writepages+0x338/0x560 mm/page-writeback.c:2571
 filemap_writeback mm/filemap.c:387 [inline]
 filemap_fdatawrite_range mm/filemap.c:412 [inline]
 filemap_write_and_wait_range+0x335/0x3f0 mm/filemap.c:684
 loop_set_status+0x245/0xd50 drivers/block/loop.c:1241
 loop_set_status64 drivers/block/loop.c:1368 [inline]
 lo_ioctl+0xc14/0x1fc0 drivers/block/loop.c:1554
 blkdev_ioctl+0x5e3/0x740 block/ioctl.c:797
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888040843c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888040843c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888040843d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                               ^
 ffff888040843d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888040843e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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