cifs: Fix missing put_xid in cifs_file_strict_mmap
authorMatthew Wilcox <mawilcox@microsoft.com>
Fri, 15 Dec 2017 20:48:32 +0000 (12:48 -0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 16 Feb 2018 19:22:43 +0000 (20:22 +0100)
commit f04a703c3d613845ae3141bfaf223489de8ab3eb upstream.

If cifs_zap_mapping() returned an error, we would return without putting
the xid that we got earlier.  Restructure cifs_file_strict_mmap() and
cifs_file_mmap() to be more similar to each other and have a single
point of return that always puts the xid.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/cifs/file.c

index 92fdf9c..7d6539a 100644 (file)
@@ -3488,20 +3488,18 @@ static const struct vm_operations_struct cifs_file_vm_ops = {
 
 int cifs_file_strict_mmap(struct file *file, struct vm_area_struct *vma)
 {
-       int rc, xid;
+       int xid, rc = 0;
        struct inode *inode = file_inode(file);
 
        xid = get_xid();
 
-       if (!CIFS_CACHE_READ(CIFS_I(inode))) {
+       if (!CIFS_CACHE_READ(CIFS_I(inode)))
                rc = cifs_zap_mapping(inode);
-               if (rc)
-                       return rc;
-       }
-
-       rc = generic_file_mmap(file, vma);
-       if (rc == 0)
+       if (!rc)
+               rc = generic_file_mmap(file, vma);
+       if (!rc)
                vma->vm_ops = &cifs_file_vm_ops;
+
        free_xid(xid);
        return rc;
 }
@@ -3511,16 +3509,16 @@ int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
        int rc, xid;
 
        xid = get_xid();
+
        rc = cifs_revalidate_file(file);
-       if (rc) {
+       if (rc)
                cifs_dbg(FYI, "Validation prior to mmap failed, error=%d\n",
                         rc);
-               free_xid(xid);
-               return rc;
-       }
-       rc = generic_file_mmap(file, vma);
-       if (rc == 0)
+       if (!rc)
+               rc = generic_file_mmap(file, vma);
+       if (!rc)
                vma->vm_ops = &cifs_file_vm_ops;
+
        free_xid(xid);
        return rc;
 }