afs: Fix page leak on afs_write_begin() failure

Fix the leak of the target page in afs_write_begin() when it fails.

Fixes: 15b4650e55e0 ("afs: convert to new aops")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Nick Piggin <npiggin@gmail.com>

diff --git a/fs/afs/write.c b/fs/afs/write.c
index 02facb19a0f1d002cc7711d48e79c007806a199e..7fae9f8b38eb3dc91769371b777cf7fe2184fe92 100644 (file)
--- a/fs/afs/write.c
+++ b/fs/afs/write.c
@@ -76,7 +76,7 @@ static int afs_fill_page(struct afs_vnode *vnode, struct key *key,
  */
 int afs_write_begin(struct file *file, struct address_space *mapping,
                    loff_t pos, unsigned len, unsigned flags,
-                   struct page **pagep, void **fsdata)
+                   struct page **_page, void **fsdata)
 {
        struct afs_vnode *vnode = AFS_FS_I(file_inode(file));
        struct page *page;
@@ -110,9 +110,6 @@ int afs_write_begin(struct file *file, struct address_space *mapping,
                SetPageUptodate(page);
        }
 
-       /* page won't leak in error case: it eventually gets cleaned off LRU */
-       *pagep = page;
-
 try_again:
        /* See if this page is already partially written in a way that we can
         * merge the new write with.
@@ -155,6 +152,7 @@ try_again:
                set_page_private(page, priv);
        else
                attach_page_private(page, (void *)priv);
+       *_page = page;
        _leave(" = 0");
        return 0;
 
@@ -164,17 +162,18 @@ try_again:
 flush_conflicting_write:
        _debug("flush conflict");
        ret = write_one_page(page);
-       if (ret < 0) {
-               _leave(" = %d", ret);
-               return ret;
-       }
+       if (ret < 0)
+               goto error;
 
        ret = lock_page_killable(page);
-       if (ret < 0) {
-               _leave(" = %d", ret);
-               return ret;
-       }
+       if (ret < 0)
+               goto error;
        goto try_again;
+
+error:
+       put_page(page);
+       _leave(" = %d", ret);
+       return ret;
 }
 
 /*