isofs: fix potential memory leak in mount option parsing

[ Upstream commit 4f34a5130a471f32f2fe7750769ab4057dc3eaa0 ]

When specifying string type mount option (e.g., iocharset)
several times in a mount, current option parsing may
cause memory leak. Hence, call kfree for previous one
in this case. Meanwhile, check memory allocation result
for it.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
index 447a24d..ed4edcd 100644 (file)
--- a/fs/isofs/inode.c
+++ b/fs/isofs/inode.c
@@ -394,7 +394,10 @@ static int parse_options(char *options, struct iso9660_options *popt)
                        break;
 #ifdef CONFIG_JOLIET
                case Opt_iocharset:
+                       kfree(popt->iocharset);
                        popt->iocharset = match_strdup(&args[0]);
+                       if (!popt->iocharset)
+                               return 0;
                        break;
 #endif
                case Opt_map_a: