loop0: detected capacity change from 0 to 256
exFAT-fs (loop0): failed to load upcase table (idx : 0x0000fd4f, chksum : 0x3963664b, utbl_chksum : 0xe619d30d)
=====================================================
BUG: KMSAN: uninit-value in iov_iter_alignment_iovec+0x1a8/0x470 lib/iov_iter.c:788
 iov_iter_alignment_iovec+0x1a8/0x470 lib/iov_iter.c:788
 iov_iter_alignment+0x1aa/0x290 lib/iov_iter.c:833
 __blockdev_direct_IO+0x170/0x6470 fs/direct-io.c:1122
 blockdev_direct_IO include/linux/fs.h:3217 [inline]
 exfat_direct_IO+0x2c2/0x8f0 fs/exfat/inode.c:526
 generic_file_direct_write+0x188/0x5c0 mm/filemap.c:3941
 __generic_file_write_iter+0x245/0x460 mm/filemap.c:4107
 exfat_file_write_iter+0x30b/0xa00 fs/exfat/file.c:592
 io_write+0x9d7/0x1e00 io_uring/rw.c:1048
 io_issue_sqe+0x429/0x22c0 io_uring/io_uring.c:1710
 io_queue_sqe io_uring/io_uring.c:1924 [inline]
 io_submit_sqe io_uring/io_uring.c:2180 [inline]
 io_submit_sqes+0x1259/0x2f20 io_uring/io_uring.c:2295
 __do_sys_io_uring_enter io_uring/io_uring.c:3210 [inline]
 __se_sys_io_uring_enter+0x40c/0x3cb0 io_uring/io_uring.c:3147
 __x64_sys_io_uring_enter+0x11f/0x1a0 io_uring/io_uring.c:3147
 x64_sys_call+0x2b54/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:427
 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

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:3994 [inline]
 slab_alloc_node mm/slub.c:4037 [inline]
 __do_kmalloc_node mm/slub.c:4157 [inline]
 __kmalloc_noprof+0x661/0xf30 mm/slub.c:4170
 kmalloc_noprof include/linux/slab.h:685 [inline]
 io_alloc_async_data+0xc0/0x220 io_uring/io_uring.c:1621
 io_rw_alloc_async io_uring/rw.c:218 [inline]
 io_prep_rw_setup io_uring/rw.c:235 [inline]
 io_prep_rw+0x921/0xcd0 io_uring/rw.c:276
 io_prep_rwv+0xb3/0x4e0 io_uring/rw.c:295
 io_prep_writev+0x3a/0x50 io_uring/rw.c:315
 io_init_req io_uring/io_uring.c:2095 [inline]
 io_submit_sqe io_uring/io_uring.c:2142 [inline]
 io_submit_sqes+0x112e/0x2f20 io_uring/io_uring.c:2295
 __do_sys_io_uring_enter io_uring/io_uring.c:3210 [inline]
 __se_sys_io_uring_enter+0x40c/0x3cb0 io_uring/io_uring.c:3147
 __x64_sys_io_uring_enter+0x11f/0x1a0 io_uring/io_uring.c:3147
 x64_sys_call+0x2b54/0x3ba0 arch/x86/include/generated/asm/syscalls_64.h:427
 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

CPU: 0 UID: 0 PID: 10033 Comm: syz.0.1362 Not tainted 6.11.0-rc4-syzkaller-00002-gb0da640826ba #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
=====================================================