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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
 exfat_file_write_iter+0x1f1/0x12a0 fs/exfat/file.c:588
 aio_write+0x72b/0x9d0 fs/aio.c:1633
 io_submit_one+0x283f/0x3280 fs/aio.c:2052
 __do_compat_sys_io_submit fs/aio.c:2153 [inline]
 __se_compat_sys_io_submit+0x287/0x720 fs/aio.c:2123
 __ia32_compat_sys_io_submit+0x93/0xe0 fs/aio.c:2123
 ia32_sys_call+0x2f60/0x4180 arch/x86/include/generated/asm/syscalls_32.h:249
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:411
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:449
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

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: 15869 Comm: syz.0.3598 Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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