cifs: Replace wrtPending with a real reference count

Currently, cifs_close() tries to wait until all I/O is complete and then
frees the file private data.  If I/O does not completely in a reasonable
amount of time it frees the structure anyway, leaving a potential use-
after-free situation.

This patch changes the wrtPending counter to a complete reference count and
lets the last user free the structure.

Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index 4326ffd90fa9..a6424cfc0121 100644
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -153,7 +153,7 @@ cifs_fill_fileinfo(struct inode *newinode, __u16 fileHandle,
         mutex_init(&pCifsFile->fh_mutex);
         mutex_init(&pCifsFile->lock_mutex);
         INIT_LIST_HEAD(&pCifsFile->llist);
-        atomic_set(&pCifsFile->wrtPending, 0);
+        atomic_set(&pCifsFile->count, 1);
 
         /* set the following in open now
                         pCifsFile->pfile = file; */