Ext2: free memory allocated and forget buffer head when io error happens

Add a necessary check when an io error happens.
If io error happens,free the memory allocated and forget
buffer head.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 12 insertions, 0 deletions

diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 6363ac66fafa..c3881e56662e 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -495,6 +495,10 @@ static int ext2_alloc_branch(struct inode *inode,
                  * parent to disk.
                  */
                 bh = sb_getblk(inode->i_sb, new_blocks[n-1]);
+                if (unlikely(!bh)) {
+                        err = -ENOMEM;
+                        goto failed;
+                }
                 branch[n].bh = bh;
                 lock_buffer(bh);
                 memset(bh->b_data, 0, blocksize);
@@ -523,6 +527,14 @@ static int ext2_alloc_branch(struct inode *inode,
         }
         *blks = num;
         return err;
+
+failed:
+        for (i = 1; i < n; i++)
+                bforget(branch[i].bh);
+        for (i = 0; i < indirect_blks; i++)
+                ext2_free_blocks(inode, new_blocks[i], 1);
+        ext2_free_blocks(inode, new_blocks[i], num);
+        return err;
 }
 
 /**