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BUG: KMSAN: uninit-value in iov_iter_alignment_iovec+0x1a8/0x470 lib/iov_iter.c:894
 iov_iter_alignment_iovec+0x1a8/0x470 lib/iov_iter.c:894
 iov_iter_alignment+0x1ac/0x2d0 lib/iov_iter.c:939
 __blockdev_direct_IO+0x170/0x6460 fs/direct-io.c:1121
 blockdev_direct_IO include/linux/fs.h:3280 [inline]
 exfat_direct_IO+0x191/0x900 fs/exfat/inode.c:482
 generic_file_direct_write+0x275/0x6a0 mm/filemap.c:3977
 __generic_file_write_iter+0x242/0x460 mm/filemap.c:4141
 exfat_file_write_iter+0x894/0xfb0 fs/exfat/file.c:598
 aio_write+0x72b/0x9d0 fs/aio.c:1633
 io_submit_one+0x283f/0x3280 fs/aio.c:2052
 __do_sys_io_submit fs/aio.c:2111 [inline]
 __se_sys_io_submit+0x275/0x700 fs/aio.c:2081
 __x64_sys_io_submit+0x96/0xe0 fs/aio.c:2081
 x64_sys_call+0x2370/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:210
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Local variable inline_vecs created at:
 aio_write+0x4f/0x9d0 fs/aio.c:1610
 io_submit_one+0x283f/0x3280 fs/aio.c:2052

CPU: 0 UID: 0 PID: 6498 Comm: syz.1.178 Not tainted 6.12.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
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