From f223ebffa185cc8da934333c5a31ff2d4f992dc9 Mon Sep 17 00:00:00 2001 From: Bartlomiej Kubik Date: Wed, 26 Nov 2025 23:02:51 +0100 Subject: [PATCH] fs/ntfs3: Initialize new folios before use KMSAN reports an uninitialized value in longest_match_std(), invoked from ntfs_compress_write(). When new folios are allocated without being marked uptodate and ni_read_frame() is skipped because the caller expects the frame to be completely overwritten, some reserved folios may remain only partially filled, leaving the rest memory uninitialized. Fixes: 584f60ba22f7 ("ntfs3: Convert ntfs_get_frame_pages() to use a folio") Tested-by: syzbot+08d8956768c96a2c52cf@syzkaller.appspotmail.com Reported-by: syzbot+08d8956768c96a2c52cf@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=08d8956768c96a2c52cf Signed-off-by: Bartlomiej Kubik Signed-off-by: Konstantin Komarov --- fs/ntfs3/file.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ntfs3/file.c b/fs/ntfs3/file.c index 2e7b2e566ebe1..732260087066d 100644 --- a/fs/ntfs3/file.c +++ b/fs/ntfs3/file.c @@ -995,7 +995,7 @@ static int ntfs_get_frame_pages(struct address_space *mapping, pgoff_t index, folio = __filemap_get_folio(mapping, index, FGP_LOCK | FGP_ACCESSED | FGP_CREAT, - gfp_mask); + gfp_mask | __GFP_ZERO); if (IS_ERR(folio)) { while (npages--) { folio = page_folio(pages[npages]); -- 2.47.3