1 files changed, 23 insertions, 17 deletions

diff --git a/net/rxrpc/key.c b/net/rxrpc/key.c
index 9fdc1f031c9da..e0c29ebe6b6d3 100644
--- a/net/rxrpc/key.c
+++ b/net/rxrpc/key.c
@@ -13,6 +13,7 @@
 #include <crypto/skcipher.h>
 #include <linux/module.h>
 #include <linux/net.h>
+#include <linux/overflow.h>
 #include <linux/skbuff.h>
 #include <linux/key-type.h>
 #include <linux/ctype.h>
@@ -72,7 +73,7 @@ static int rxrpc_preparse_xdr_rxkad(struct key_preparsed_payload *prep,
 		return -EKEYREJECTED;
 
 	plen = sizeof(*token) + sizeof(*token->kad) + tktlen;
-	prep->quotalen = datalen + plen;
+	prep->quotalen += datalen + plen;
 
 	plen -= sizeof(*token);
 	token = kzalloc(sizeof(*token), GFP_KERNEL);
@@ -171,7 +172,7 @@ static int rxrpc_preparse_xdr_yfs_rxgk(struct key_preparsed_payload *prep,
 	size_t plen;
 	const __be32 *ticket, *key;
 	s64 tmp;
-	u32 tktlen, keylen;
+	size_t raw_keylen, raw_tktlen, keylen, tktlen;
 
 	_enter(",{%x,%x,%x,%x},%x",
 	       ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
@@ -181,32 +182,36 @@ static int rxrpc_preparse_xdr_yfs_rxgk(struct key_preparsed_payload *prep,
 		goto reject;
 
 	key = xdr + (6 * 2 + 1);
-	keylen = ntohl(key[-1]);
-	_debug("keylen: %x", keylen);
-	keylen = round_up(keylen, 4);
+	raw_keylen = ntohl(key[-1]);
+	_debug("keylen: %zx", raw_keylen);
+	if (raw_keylen > AFSTOKEN_GK_KEY_MAX)
+		goto reject;
+	keylen = round_up(raw_keylen, 4);
 	if ((6 * 2 + 2) * 4 + keylen > toklen)
 		goto reject;
 
 	ticket = xdr + (6 * 2 + 1 + (keylen / 4) + 1);
-	tktlen = ntohl(ticket[-1]);
-	_debug("tktlen: %x", tktlen);
-	tktlen = round_up(tktlen, 4);
+	raw_tktlen = ntohl(ticket[-1]);
+	_debug("tktlen: %zx", raw_tktlen);
+	if (raw_tktlen > AFSTOKEN_GK_TOKEN_MAX)
+		goto reject;
+	tktlen = round_up(raw_tktlen, 4);
 	if ((6 * 2 + 2) * 4 + keylen + tktlen != toklen) {
-		kleave(" = -EKEYREJECTED [%x!=%x, %x,%x]",
+		kleave(" = -EKEYREJECTED [%zx!=%x, %zx,%zx]",
 		       (6 * 2 + 2) * 4 + keylen + tktlen, toklen,
 		       keylen, tktlen);
 		goto reject;
 	}
 
 	plen = sizeof(*token) + sizeof(*token->rxgk) + tktlen + keylen;
-	prep->quotalen = datalen + plen;
+	prep->quotalen += datalen + plen;
 
 	plen -= sizeof(*token);
 	token = kzalloc(sizeof(*token), GFP_KERNEL);
 	if (!token)
 		goto nomem;
 
-	token->rxgk = kzalloc(sizeof(*token->rxgk) + keylen, GFP_KERNEL);
+	token->rxgk = kzalloc(struct_size_t(struct rxgk_key, _key, raw_keylen), GFP_KERNEL);
 	if (!token->rxgk)
 		goto nomem_token;
 
@@ -221,9 +226,9 @@ static int rxrpc_preparse_xdr_yfs_rxgk(struct key_preparsed_payload *prep,
 	token->rxgk->enctype	= tmp = xdr_dec64(xdr + 5 * 2);
 	if (tmp < 0 || tmp > UINT_MAX)
 		goto reject_token;
-	token->rxgk->key.len	= ntohl(key[-1]);
+	token->rxgk->key.len	= raw_keylen;
 	token->rxgk->key.data	= token->rxgk->_key;
-	token->rxgk->ticket.len = ntohl(ticket[-1]);
+	token->rxgk->ticket.len = raw_tktlen;
 
 	if (token->rxgk->endtime != 0) {
 		expiry = rxrpc_s64_to_time64(token->rxgk->endtime);
@@ -236,8 +241,7 @@ static int rxrpc_preparse_xdr_yfs_rxgk(struct key_preparsed_payload *prep,
 	memcpy(token->rxgk->key.data, key, token->rxgk->key.len);
 
 	/* Pad the ticket so that we can use it directly in XDR */
-	token->rxgk->ticket.data = kzalloc(round_up(token->rxgk->ticket.len, 4),
-					   GFP_KERNEL);
+	token->rxgk->ticket.data = kzalloc(tktlen, GFP_KERNEL);
 	if (!token->rxgk->ticket.data)
 		goto nomem_yrxgk;
 	memcpy(token->rxgk->ticket.data, ticket, token->rxgk->ticket.len);
@@ -274,6 +278,7 @@ nomem_token:
 nomem:
 	return -ENOMEM;
 reject_token:
+	kfree(token->rxgk);
 	kfree(token);
 reject:
 	return -EKEYREJECTED;
@@ -460,6 +465,7 @@ static int rxrpc_preparse(struct key_preparsed_payload *prep)
 	memcpy(&kver, prep->data, sizeof(kver));
 	prep->data += sizeof(kver);
 	prep->datalen -= sizeof(kver);
+	prep->quotalen = 0;
 
 	_debug("KEY I/F VERSION: %u", kver);
 
@@ -497,7 +503,7 @@ static int rxrpc_preparse(struct key_preparsed_payload *prep)
 		goto error;
 
 	plen = sizeof(*token->kad) + v1->ticket_length;
-	prep->quotalen = plen + sizeof(*token);
+	prep->quotalen += plen + sizeof(*token);
 
 	ret = -ENOMEM;
 	token = kzalloc(sizeof(*token), GFP_KERNEL);
@@ -616,7 +622,7 @@ int rxrpc_request_key(struct rxrpc_sock *rx, sockptr_t optval, int optlen)
 
 	_enter("");
 
-	if (optlen <= 0 || optlen > PAGE_SIZE - 1 || rx->securities)
+	if (optlen <= 0 || optlen > PAGE_SIZE - 1 || rx->key)
 		return -EINVAL;
 
 	description = memdup_sockptr_nul(optval, optlen);