[PATCH] ext2: prevent div-by-zero on corrupted fs

Mounting an ext2 filesystem with zero s_inodes_per_group will cause a
divide error.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index f2702cda977981673264f96c33f8d974545d9694..681dea8f9532ee744932bdc6fa9762360d892b45 100644 (file)
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -775,7 +775,7 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
        if (EXT2_INODE_SIZE(sb) == 0)
                goto cantfind_ext2;
        sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
-       if (sbi->s_inodes_per_block == 0)
+       if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
                goto cantfind_ext2;
        sbi->s_itb_per_group = sbi->s_inodes_per_group /
                                        sbi->s_inodes_per_block;