syzbot

loop0: detected capacity change from 0 to 4096
ntfs3(loop0): Different NTFS sector size (2048) and media sector size (512).
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BUG: KMSAN: uninit-value in ntfs_iomap_begin+0x8c0/0x1460 fs/ntfs3/inode.c:825
 ntfs_iomap_begin+0x8c0/0x1460 fs/ntfs3/inode.c:825
 iomap_iter+0x9b7/0x1540 fs/iomap/iter.c:110
 iomap_read_folio+0x262/0x750 fs/iomap/buffered-io.c:587
 ntfs_read_folio+0x74a/0x770 fs/ntfs3/inode.c:697
 filemap_read_folio mm/filemap.c:2496 [inline]
 do_read_cache_folio+0x993/0x1470 mm/filemap.c:4096
 do_read_cache_page mm/filemap.c:4162 [inline]
 read_cache_page+0x63/0x1e0 mm/filemap.c:4171
 read_mapping_page include/linux/pagemap.h:1022 [inline]
 inode_read_data+0xb3/0x6b0 fs/ntfs3/inode.c:1116
 ntfs_fill_super+0x6a24/0x7e50 fs/ntfs3/super.c:1549
 get_tree_bdev_flags+0x6e6/0x920 fs/super.c:1694
 get_tree_bdev+0x38/0x50 fs/super.c:1717
 ntfs_fs_get_tree+0x35/0x40 fs/ntfs3/super.c:1788
 vfs_get_tree+0xb3/0x5d0 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3760 [inline]
 do_new_mount+0x885/0x1dd0 fs/namespace.c:3836
 path_mount+0x7a2/0x20b0 fs/namespace.c:4146
 do_mount fs/namespace.c:4159 [inline]
 __do_sys_mount fs/namespace.c:4348 [inline]
 __se_sys_mount+0x704/0x7f0 fs/namespace.c:4325
 __x64_sys_mount+0xe4/0x150 fs/namespace.c:4325
 x64_sys_call+0x39f0/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x134/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable lcn created at:
 ntfs_iomap_begin+0x15d/0x1460 fs/ntfs3/inode.c:786
 iomap_iter+0x9b7/0x1540 fs/iomap/iter.c:110

CPU: 1 UID: 0 PID: 6051 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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