Kernel bug: KMSAN: uninit-value in attr_set_size
Subsystem: ntfs3
Status: fixed

Crash report:
ntfs3(loop0): Failed to initialize $Extend.
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BUG: KMSAN: uninit-value in attr_set_size+0x471b/0x6740 fs/ntfs3/attrib.c:653
 attr_set_size+0x471b/0x6740 fs/ntfs3/attrib.c:653
 ntfs_set_size+0x222/0x330 fs/ntfs3/inode.c:861
 ntfs_extend+0x27c/0xf50 fs/ntfs3/file.c:359
 ntfs_file_write_iter+0x627/0x10d0 fs/ntfs3/file.c:1220
 iter_file_splice_write+0x12b2/0x2170 fs/splice.c:738
 ntfs_file_splice_write+0x21d/0x370 fs/ntfs3/file.c:1347
 do_splice_from fs/splice.c:938 [inline]
 direct_splice_actor+0x317/0x7d0 fs/splice.c:1161
 splice_direct_to_actor+0x99f/0x1550 fs/splice.c:1105
 do_splice_direct_actor fs/splice.c:1204 [inline]
 do_splice_direct+0x1e0/0x350 fs/splice.c:1230
 do_sendfile+0x9eb/0x1110 fs/read_write.c:1370
 __do_sys_sendfile64 fs/read_write.c:1431 [inline]
 __se_sys_sendfile64+0x1e3/0x280 fs/read_write.c:1417
 __x64_sys_sendfile64+0xbd/0x120 fs/read_write.c:1417
 x64_sys_call+0x36b8/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 attr_set_size+0x4714/0x6740 fs/ntfs3/attrib.c:655
 ntfs_set_size+0x222/0x330 fs/ntfs3/inode.c:861
 ntfs_extend+0x27c/0xf50 fs/ntfs3/file.c:359
 ntfs_file_write_iter+0x627/0x10d0 fs/ntfs3/file.c:1220
 iter_file_splice_write+0x12b2/0x2170 fs/splice.c:738
 ntfs_file_splice_write+0x21d/0x370 fs/ntfs3/file.c:1347
 do_splice_from fs/splice.c:938 [inline]
 direct_splice_actor+0x317/0x7d0 fs/splice.c:1161
 splice_direct_to_actor+0x99f/0x1550 fs/splice.c:1105
 do_splice_direct_actor fs/splice.c:1204 [inline]
 do_splice_direct+0x1e0/0x350 fs/splice.c:1230
 do_sendfile+0x9eb/0x1110 fs/read_write.c:1370
 __do_sys_sendfile64 fs/read_write.c:1431 [inline]
 __se_sys_sendfile64+0x1e3/0x280 fs/read_write.c:1417
 __x64_sys_sendfile64+0xbd/0x120 fs/read_write.c:1417
 x64_sys_call+0x36b8/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 ni_create_attr_list+0x1b9b/0x1db0 fs/ntfs3/frecord.c:872
 attr_set_size+0x4174/0x6740 fs/ntfs3/attrib.c:640
 ntfs_set_size+0x222/0x330 fs/ntfs3/inode.c:861
 ntfs_extend+0x27c/0xf50 fs/ntfs3/file.c:359
 ntfs_file_write_iter+0x627/0x10d0 fs/ntfs3/file.c:1220
 iter_file_splice_write+0x12b2/0x2170 fs/splice.c:738
 ntfs_file_splice_write+0x21d/0x370 fs/ntfs3/file.c:1347
 do_splice_from fs/splice.c:938 [inline]
 direct_splice_actor+0x317/0x7d0 fs/splice.c:1161
 splice_direct_to_actor+0x99f/0x1550 fs/splice.c:1105
 do_splice_direct_actor fs/splice.c:1204 [inline]
 do_splice_direct+0x1e0/0x350 fs/splice.c:1230
 do_sendfile+0x9eb/0x1110 fs/read_write.c:1370
 __do_sys_sendfile64 fs/read_write.c:1431 [inline]
 __se_sys_sendfile64+0x1e3/0x280 fs/read_write.c:1417
 __x64_sys_sendfile64+0xbd/0x120 fs/read_write.c:1417
 x64_sys_call+0x36b8/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4953 [inline]
 slab_alloc_node mm/slub.c:5245 [inline]
 __do_kmalloc_node mm/slub.c:5602 [inline]
 __kmalloc_noprof+0xabb/0x1b40 mm/slub.c:5615
 kmalloc_noprof include/linux/slab.h:961 [inline]
 ni_create_attr_list+0x1ca/0x1db0 fs/ntfs3/frecord.c:770
 attr_set_size+0x4174/0x6740 fs/ntfs3/attrib.c:640
 ntfs_set_size+0x222/0x330 fs/ntfs3/inode.c:861
 ntfs_extend+0x27c/0xf50 fs/ntfs3/file.c:359
 ntfs_file_write_iter+0x627/0x10d0 fs/ntfs3/file.c:1220
 iter_file_splice_write+0x12b2/0x2170 fs/splice.c:738
 ntfs_file_splice_write+0x21d/0x370 fs/ntfs3/file.c:1347
 do_splice_from fs/splice.c:938 [inline]
 direct_splice_actor+0x317/0x7d0 fs/splice.c:1161
 splice_direct_to_actor+0x99f/0x1550 fs/splice.c:1105
 do_splice_direct_actor fs/splice.c:1204 [inline]
 do_splice_direct+0x1e0/0x350 fs/splice.c:1230
 do_sendfile+0x9eb/0x1110 fs/read_write.c:1370
 __do_sys_sendfile64 fs/read_write.c:1431 [inline]
 __se_sys_sendfile64+0x1e3/0x280 fs/read_write.c:1417
 __x64_sys_sendfile64+0xbd/0x120 fs/read_write.c:1417
 x64_sys_call+0x36b8/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 6199 Comm: syz.0.54 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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