syzbot

EXT4-fs error (device loop1): ext4_iget_extra_inode:5073: inode #12: comm syz.1.1024: corrupted in-inode xattr: bad e_name length
==================================================================
BUG: KCSAN: data-race in _copy_to_iter / memcpy_and_pad

read to 0xffff88811e071400 of 1024 bytes by task 3314 on cpu 0:
 instrument_copy_to_user include/linux/instrumented.h:113 [inline]
 copy_to_user_iter lib/iov_iter.c:24 [inline]
 iterate_ubuf include/linux/iov_iter.h:30 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:302 [inline]
 iterate_and_advance include/linux/iov_iter.h:330 [inline]
 _copy_to_iter+0x130/0xea0 lib/iov_iter.c:197
 copy_page_to_iter+0x18f/0x2d0 lib/iov_iter.c:374
 copy_folio_to_iter include/linux/uio.h:204 [inline]
 filemap_read+0x407/0xa10 mm/filemap.c:2851
 blkdev_read_iter+0x22d/0x2e0 block/fops.c:856
 new_sync_read fs/read_write.c:491 [inline]
 vfs_read+0x6c0/0x7f0 fs/read_write.c:572
 ksys_read+0xdc/0x1a0 fs/read_write.c:715
 __do_sys_read fs/read_write.c:724 [inline]
 __se_sys_read fs/read_write.c:722 [inline]
 __x64_sys_read+0x40/0x50 fs/read_write.c:722
 x64_sys_call+0x2889/0x3000 arch/x86/include/generated/asm/syscalls_64.h:1
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff88811e0715a8 of 21 bytes by task 5791 on cpu 1:
 memcpy_and_pad+0x48/0x80 lib/string_helpers.c:1007
 ext4_update_super+0x451/0xb70 fs/ext4/super.c:6206
 ext4_commit_super+0x40/0x280 fs/ext4/super.c:6248
 ext4_handle_error+0x452/0x550 fs/ext4/super.c:718
 __ext4_error_inode+0x204/0x420 fs/ext4/super.c:861
 check_xattrs+0x530/0x7f0 fs/ext4/xattr.c:298
 __xattr_check_inode+0x3c/0x50 fs/ext4/xattr.c:319
 ext4_iget_extra_inode+0xfb/0x1f0 fs/ext4/inode.c:5072
 __ext4_iget+0x15b5/0x2350 fs/ext4/inode.c:5387
 ext4_orphan_get+0x152/0x430 fs/ext4/ialloc.c:1391
 ext4_orphan_cleanup+0x5fa/0xa00 fs/ext4/orphan.c:465
 __ext4_fill_super fs/ext4/super.c:5658 [inline]
 ext4_fill_super+0x3476/0x3800 fs/ext4/super.c:5777
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1691
 get_tree_bdev+0x1f/0x30 fs/super.c:1714
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5809
 vfs_get_tree+0x57/0x1d0 fs/super.c:1751
 fc_mount fs/namespace.c:1199 [inline]
 do_new_mount_fc fs/namespace.c:3636 [inline]
 do_new_mount+0x288/0x700 fs/namespace.c:3712
 path_mount+0x4d0/0xbc0 fs/namespace.c:4022
 do_mount fs/namespace.c:4035 [inline]
 __do_sys_mount fs/namespace.c:4224 [inline]
 __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4201
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4201
 x64_sys_call+0x2cca/0x3000 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 5791 Comm: syz.1.1024 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
==================================================================
EXT4-fs error (device loop1): ext4_orphan_get:1396: comm syz.1.1024: couldn't read orphan inode 12 (err -117)