[PATCH] SUNRPC: Add a check for gss_release_msg

From: Aditya Pakki <pakki001@umn.edu>
To: pakki001@umn.edu
Cc: "J. Bruce Fields" <bfields@fieldses.org>,
	Chuck Lever <chuck.lever@oracle.com>,
	Trond Myklebust <trond.myklebust@hammerspace.com>,
	Anna Schumaker <anna.schumaker@netapp.com>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	Dave Wysochanski <dwysocha@redhat.com>,
	linux-nfs@vger.kernel.org, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH] SUNRPC: Add a check for gss_release_msg
Date: Tue,  6 Apr 2021 19:16:56 -0500
Message-ID: <20210407001658.2208535-1-pakki001@umn.edu> (raw)

In gss_pipe_destroy_msg(), in case of error in msg, gss_release_msg
deletes gss_msg. The patch adds a check to avoid a potential double
free.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
---
 net/sunrpc/auth_gss/auth_gss.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index 5f42aa5fc612..eb52eebb3923 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -848,7 +848,8 @@ gss_pipe_destroy_msg(struct rpc_pipe_msg *msg)
 			warn_gssd();
 		gss_release_msg(gss_msg);
 	}
-	gss_release_msg(gss_msg);
+	if (gss_msg)
+		gss_release_msg(gss_msg);
 }
 
 static void gss_pipe_dentry_destroy(struct dentry *dir,
-- 
2.25.1

