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BUG: KASAN: out-of-bounds in ext4_xattr_set_entry+0x1576/0x20b0 fs/ext4/xattr.c:1761
Read of size 18446744073709551600 at addr ffff88806c2240b8 by task syz.3.2538/18832

CPU: 0 UID: 0 PID: 18832 Comm: syz.3.2538 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x156/0x4c9 mm/kasan/report.c:482
 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595
 check_region_inline mm/kasan/generic.c:186 [inline]
 kasan_check_range+0x10f/0x1e0 mm/kasan/generic.c:200
 __asan_memmove+0x23/0x60 mm/kasan/shadow.c:94
 ext4_xattr_set_entry+0x1576/0x20b0 fs/ext4/xattr.c:1761
 ext4_xattr_ibody_set+0x3d3/0x5d0 fs/ext4/xattr.c:2273
 ext4_destroy_inline_data_nolock+0x28b/0x5c0 fs/ext4/inline.c:472
 ext4_convert_inline_data_nolock+0x17d/0xad0 fs/ext4/inline.c:1123
 ext4_convert_inline_data+0x540/0x610 fs/ext4/inline.c:1994
 ext4_fallocate+0x1f8/0x3730 fs/ext4/extents.c:4875
 vfs_fallocate+0x576/0x10d0 fs/open.c:340
 ksys_fallocate fs/open.c:364 [inline]
 __do_sys_fallocate fs/open.c:369 [inline]
 __se_sys_fallocate fs/open.c:367 [inline]
 __x64_sys_fallocate+0xd5/0x140 fs/open.c:367
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f462c99c799
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:00007f462d7cf028 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 00007f462cc16090 RCX: 00007f462c99c799
RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000007
RBP: 00007f462ca32c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000800000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f462cc16128 R14: 00007f462cc16090 R15: 00007ffd15c0f978
 </TASK>

The buggy address belongs to the physical page:
page: refcount:3 mapcount:0 mapping:ffff8880245808c8 index:0x3 pfn:0x6c224
memcg:ffff88801caf9a80
aops:def_blk_aops ino:700003 dentry name(?):""
flags: 0xfff20000004828(uptodate|lru|owner_2|private|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff20000004828 ffffea0002882388 ffff88801dec5c60 ffff8880245808c8
raw: 0000000000000003 ffff8880483d8740 00000003ffffffff ffff88801caf9a80
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x152c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 16076, tgid 16076 (udevd), ts 1556934806916, free_ts 1556932807125
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x153/0x170 mm/page_alloc.c:1889
 prep_new_page mm/page_alloc.c:1897 [inline]
 get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3962
 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5250
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2490
 alloc_pages_noprof mm/mempolicy.c:2581 [inline]
 folio_alloc_noprof+0x22/0x330 mm/mempolicy.c:2591
 filemap_alloc_folio_noprof.part.0+0x377/0x450 mm/filemap.c:1013
 filemap_alloc_folio_noprof+0x5e/0x80 mm/filemap.c:1014
 ractl_alloc_folio+0x1d/0x100 mm/readahead.c:189
 page_cache_ra_unbounded+0x357/0xa40 mm/readahead.c:277
 do_page_cache_ra mm/readahead.c:334 [inline]
 force_page_cache_ra+0x269/0x370 mm/readahead.c:364
 page_cache_sync_ra+0x1b6/0xb10 mm/readahead.c:582
 filemap_get_pages+0x6cf/0x2050 mm/filemap.c:2695
 filemap_read+0x3b5/0x10a0 mm/filemap.c:2805
 blkdev_read_iter+0x2c4/0x4f0 block/fops.c:855
 new_sync_read fs/read_write.c:493 [inline]
 vfs_read+0x825/0xb30 fs/read_write.c:574
 ksys_read+0x12a/0x250 fs/read_write.c:717
page last free pid 17481 tgid 17481 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1433 [inline]
 __free_frozen_pages+0x7e1/0x10d0 mm/page_alloc.c:2978
 vfree.part.0+0x12b/0x9d0 mm/vmalloc.c:3479
 vfree+0x55/0x80 mm/vmalloc.c:3456
 copy_entries_to_user net/ipv4/netfilter/ip_tables.c:866 [inline]
 get_entries net/ipv4/netfilter/ip_tables.c:1022 [inline]
 do_ipt_get_ctl+0x88d/0xa80 net/ipv4/netfilter/ip_tables.c:1668
 nf_getsockopt+0x7c/0xe0 net/netfilter/nf_sockopt.c:116
 ip_getsockopt+0x192/0x1e0 net/ipv4/ip_sockglue.c:1777
 tcp_getsockopt+0xa1/0x110 net/ipv4/tcp.c:4894
 do_sock_getsockopt+0x259/0x3d0 net/socket.c:2383
 __sys_getsockopt+0x148/0x260 net/socket.c:2412
 __do_sys_getsockopt net/socket.c:2419 [inline]
 __se_sys_getsockopt net/socket.c:2416 [inline]
 __x64_sys_getsockopt+0xbd/0x160 net/socket.c:2416
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88806c223f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88806c224000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88806c224080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                        ^
 ffff88806c224100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88806c224180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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