fat: fix fat_ra_init() for data clusters == 0

If data clusters == 0, fat_ra_init() calls the ->ent_blocknr() for the cluster beyond ->max_clusters. This checks the limit before initialization to suppress the warning. Reported-by: [email protected] Signed-off-by: OGAWA Hirofumi <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
niw · Aug 12, 2020 · a090a5a · a090a5a
1 parent 4ecfed6
commit a090a5a
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/fs/fat/fatent.c b/fs/fat/fatent.c
@@ -657,6 +657,9 @@ static void fat_ra_init(struct super_block *sb, struct fatent_ra *ra,
 	unsigned long ra_pages = sb->s_bdi->ra_pages;
 	unsigned int reada_blocks;
 
+	if (fatent->entry >= ent_limit)
+		return;
+
 	if (ra_pages > sb->s_bdi->io_pages)
 		ra_pages = rounddown(ra_pages, sb->s_bdi->io_pages);
 	reada_blocks = ra_pages << (PAGE_SHIFT - sb->s_blocksize_bits + 1);