[PATCH] [v3] SUNRPC: fix some memleaks in gssx_dec_option_array

From: Zhipeng Lu <alexious@zju.edu.cn>
To: alexious@zju.edu.cn
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>,
	Anna Schumaker <anna@kernel.org>,
	Chuck Lever <chuck.lever@oracle.com>,
	Jeff Layton <jlayton@kernel.org>, Neil Brown <neilb@suse.de>,
	Olga Kornievskaia <kolga@netapp.com>,
	Dai Ngo <Dai.Ngo@oracle.com>, Tom Talpey <tom@talpey.com>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	"J. Bruce Fields" <bfields@fieldses.org>,
	Simo Sorce <simo@redhat.com>,
	linux-nfs@vger.kernel.org, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH] [v3] SUNRPC: fix some memleaks in gssx_dec_option_array
Date: Tue,  2 Jan 2024 13:38:13 +0800	[thread overview]
Message-ID: <20240102053815.3611872-1-alexious@zju.edu.cn> (raw)

The creds and oa->data need to be freed in the error-handling paths after
there allocation. So this patch add these deallocations in the
corresponding paths.

Fixes: 1d658336b05f ("SUNRPC: Add RPC based upcall mechanism for RPCGSS auth")
Signed-off-by: Zhipeng Lu <alexious@zju.edu.cn>
---
Changelog:

v2: correct some syntactic problems.
v3: delete unused label err.
---
 net/sunrpc/auth_gss/gss_rpc_xdr.c | 27 +++++++++++++++++++--------
 1 file changed, 19 insertions(+), 8 deletions(-)

diff --git a/net/sunrpc/auth_gss/gss_rpc_xdr.c b/net/sunrpc/auth_gss/gss_rpc_xdr.c
index d79f12c2550a..cb32ab9a8395 100644
--- a/net/sunrpc/auth_gss/gss_rpc_xdr.c
+++ b/net/sunrpc/auth_gss/gss_rpc_xdr.c
@@ -250,8 +250,8 @@ static int gssx_dec_option_array(struct xdr_stream *xdr,
 
 	creds = kzalloc(sizeof(struct svc_cred), GFP_KERNEL);
 	if (!creds) {
-		kfree(oa->data);
-		return -ENOMEM;
+		err = -ENOMEM;
+		goto free_oa;
 	}
 
 	oa->data[0].option.data = CREDS_VALUE;
@@ -265,29 +265,40 @@ static int gssx_dec_option_array(struct xdr_stream *xdr,
 
 		/* option buffer */
 		p = xdr_inline_decode(xdr, 4);
-		if (unlikely(p == NULL))
-			return -ENOSPC;
+		if (unlikely(p == NULL)) {
+			err = -ENOSPC;
+			goto free_creds;
+		}
 
 		length = be32_to_cpup(p);
 		p = xdr_inline_decode(xdr, length);
-		if (unlikely(p == NULL))
-			return -ENOSPC;
+		if (unlikely(p == NULL)) {
+			err = -ENOSPC;
+			goto free_creds;
+		}
 
 		if (length == sizeof(CREDS_VALUE) &&
 		    memcmp(p, CREDS_VALUE, sizeof(CREDS_VALUE)) == 0) {
 			/* We have creds here. parse them */
 			err = gssx_dec_linux_creds(xdr, creds);
 			if (err)
-				return err;
+				goto free_creds;
 			oa->data[0].value.len = 1; /* presence */
 		} else {
 			/* consume uninteresting buffer */
 			err = gssx_dec_buffer(xdr, &dummy);
 			if (err)
-				return err;
+				goto free_creds;
 		}
 	}
 	return 0;
+
+free_creds:
+	kfree(creds);
+free_oa:
+	kfree(oa->data);
+	oa->data = NULL;
+	return err;
 }
 
 static int gssx_dec_status(struct xdr_stream *xdr,
-- 
2.34.1

