[PATCH 4.14 21/21] jfs: Fix inconsistency between memory allocation and ea_buf->max_size

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Shankara Pailoor <shankarapail...@gmail.com>

commit 92d34134193e5b129dc24f8d79cb9196626e8d7a upstream.

The code is assuming the buffer is max_size length, but we weren't
allocating enough space for it.

Signed-off-by: Shankara Pailoor <shankarapail...@gmail.com>
Signed-off-by: Dave Kleikamp <dave.kleik...@oracle.com>
Cc: Guenter Roeck <li...@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 fs/jfs/xattr.c |   10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

--- a/fs/jfs/xattr.c
+++ b/fs/jfs/xattr.c
@@ -491,15 +491,17 @@ static int ea_get(struct inode *inode, s
        if (size > PSIZE) {
                /*
                 * To keep the rest of the code simple.  Allocate a
-                * contiguous buffer to work with
+                * contiguous buffer to work with. Make the buffer large
+                * enough to make use of the whole extent.
                 */
-               ea_buf->xattr = kmalloc(size, GFP_KERNEL);
+               ea_buf->max_size = (size + sb->s_blocksize - 1) &
+                   ~(sb->s_blocksize - 1);
+
+               ea_buf->xattr = kmalloc(ea_buf->max_size, GFP_KERNEL);
                if (ea_buf->xattr == NULL)
                        return -ENOMEM;
 
                ea_buf->flag = EA_MALLOC;
-               ea_buf->max_size = (size + sb->s_blocksize - 1) &
-                   ~(sb->s_blocksize - 1);
 
                if (ea_size == 0)
                        return 0;