The patch titled
Subject: fat: fix fat_ra_init() for data clusters == 0
has been added to the -mm tree. Its filename is
fat-fix-fat_ra_init-for-data-clusters-==-0.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/fat-fix-fat_ra_init-for-data-clusters-%3D%3D-0.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/fat-fix-fat_ra_init-for-data-clusters-%3D%3D-0.patch
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------------------------------------------------------
From: OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx>
Subject: 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.
Link: http://lkml.kernel.org/r/87mu462sv4.fsf@xxxxxxxxxxxxxxxxxx
Signed-off-by: OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx>
Reported-by: syzbot+756199124937b31a9b7e@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/fat/fatent.c | 3 +++
1 file changed, 3 insertions(+)
--- a/fs/fat/fatent.c~fat-fix-fat_ra_init-for-data-clusters-==-0
+++ a/fs/fat/fatent.c
@@ -657,6 +657,9 @@ static void fat_ra_init(struct super_blo
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);
_
Patches currently in -mm which might be from hirofumi@xxxxxxxxxxxxxxxxxx are
fat-fix-fat_ra_init-for-data-clusters-==-0.patch
