omfs: check bounds on block numbers before passing to sb_bread
In case of filesystem corruption, passing unchecked block numbers into
sb_bread can result in an infinite loop in __getblk(). Introduce a wrapper
function omfs_sbread() to check the block numbers and to also perform the
clus_to_blk() scaling.
Signed-off-by: Bob Copeland <me@bobcopeland.com>
diff --git a/fs/omfs/omfs.h b/fs/omfs/omfs.h
index ebe2fdb..7d414fe 100644
--- a/fs/omfs/omfs.h
+++ b/fs/omfs/omfs.h
@@ -58,6 +58,7 @@
extern int omfs_shrink_inode(struct inode *inode);
/* inode.c */
+extern struct buffer_head *omfs_bread(struct super_block *sb, sector_t block);
extern struct inode *omfs_iget(struct super_block *sb, ino_t inode);
extern struct inode *omfs_new_inode(struct inode *dir, int mode);
extern int omfs_reserve_block(struct super_block *sb, sector_t block);