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-rw-r--r--net/x25/af_x25.c67
-rw-r--r--net/x25/x25_facilities.c27
-rw-r--r--net/x25/x25_in.c15
3 files changed, 96 insertions, 13 deletions
diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c
index e56f711baccc..cbddd0cb83f1 100644
--- a/net/x25/af_x25.c
+++ b/net/x25/af_x25.c
@@ -83,6 +83,41 @@ struct compat_x25_subscrip_struct {
};
#endif
+
+int x25_parse_address_block(struct sk_buff *skb,
+ struct x25_address *called_addr,
+ struct x25_address *calling_addr)
+{
+ unsigned char len;
+ int needed;
+ int rc;
+
+ if (skb->len < 1) {
+ /* packet has no address block */
+ rc = 0;
+ goto empty;
+ }
+
+ len = *skb->data;
+ needed = 1 + (len >> 4) + (len & 0x0f);
+
+ if (skb->len < needed) {
+ /* packet is too short to hold the addresses it claims
+ to hold */
+ rc = -1;
+ goto empty;
+ }
+
+ return x25_addr_ntoa(skb->data, called_addr, calling_addr);
+
+empty:
+ *called_addr->x25_addr = 0;
+ *calling_addr->x25_addr = 0;
+
+ return rc;
+}
+
+
int x25_addr_ntoa(unsigned char *p, struct x25_address *called_addr,
struct x25_address *calling_addr)
{
@@ -554,7 +589,8 @@ static int x25_create(struct net *net, struct socket *sock, int protocol,
x25->facilities.winsize_out = X25_DEFAULT_WINDOW_SIZE;
x25->facilities.pacsize_in = X25_DEFAULT_PACKET_SIZE;
x25->facilities.pacsize_out = X25_DEFAULT_PACKET_SIZE;
- x25->facilities.throughput = X25_DEFAULT_THROUGHPUT;
+ x25->facilities.throughput = 0; /* by default don't negotiate
+ throughput */
x25->facilities.reverse = X25_DEFAULT_REVERSE;
x25->dte_facilities.calling_len = 0;
x25->dte_facilities.called_len = 0;
@@ -922,16 +958,26 @@ int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb,
/*
* Extract the X.25 addresses and convert them to ASCII strings,
* and remove them.
+ *
+ * Address block is mandatory in call request packets
*/
- addr_len = x25_addr_ntoa(skb->data, &source_addr, &dest_addr);
+ addr_len = x25_parse_address_block(skb, &source_addr, &dest_addr);
+ if (addr_len <= 0)
+ goto out_clear_request;
skb_pull(skb, addr_len);
/*
* Get the length of the facilities, skip past them for the moment
* get the call user data because this is needed to determine
* the correct listener
+ *
+ * Facilities length is mandatory in call request packets
*/
+ if (skb->len < 1)
+ goto out_clear_request;
len = skb->data[0] + 1;
+ if (skb->len < len)
+ goto out_clear_request;
skb_pull(skb,len);
/*
@@ -1415,9 +1461,20 @@ static int x25_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
if (facilities.winsize_in < 1 ||
facilities.winsize_in > 127)
break;
- if (facilities.throughput < 0x03 ||
- facilities.throughput > 0xDD)
- break;
+ if (facilities.throughput) {
+ int out = facilities.throughput & 0xf0;
+ int in = facilities.throughput & 0x0f;
+ if (!out)
+ facilities.throughput |=
+ X25_DEFAULT_THROUGHPUT << 4;
+ else if (out < 0x30 || out > 0xD0)
+ break;
+ if (!in)
+ facilities.throughput |=
+ X25_DEFAULT_THROUGHPUT;
+ else if (in < 0x03 || in > 0x0D)
+ break;
+ }
if (facilities.reverse &&
(facilities.reverse & 0x81) != 0x81)
break;
diff --git a/net/x25/x25_facilities.c b/net/x25/x25_facilities.c
index a21f6646eb3a..771bab00754b 100644
--- a/net/x25/x25_facilities.c
+++ b/net/x25/x25_facilities.c
@@ -35,7 +35,7 @@ int x25_parse_facilities(struct sk_buff *skb, struct x25_facilities *facilities,
struct x25_dte_facilities *dte_facs, unsigned long *vc_fac_mask)
{
unsigned char *p = skb->data;
- unsigned int len = *p++;
+ unsigned int len;
*vc_fac_mask = 0;
@@ -50,6 +50,14 @@ int x25_parse_facilities(struct sk_buff *skb, struct x25_facilities *facilities,
memset(dte_facs->called_ae, '\0', sizeof(dte_facs->called_ae));
memset(dte_facs->calling_ae, '\0', sizeof(dte_facs->calling_ae));
+ if (skb->len < 1)
+ return 0;
+
+ len = *p++;
+
+ if (len >= skb->len)
+ return -1;
+
while (len > 0) {
switch (*p & X25_FAC_CLASS_MASK) {
case X25_FAC_CLASS_A:
@@ -247,6 +255,8 @@ int x25_negotiate_facilities(struct sk_buff *skb, struct sock *sk,
memcpy(new, ours, sizeof(*new));
len = x25_parse_facilities(skb, &theirs, dte, &x25->vc_facil_mask);
+ if (len < 0)
+ return len;
/*
* They want reverse charging, we won't accept it.
@@ -259,9 +269,18 @@ int x25_negotiate_facilities(struct sk_buff *skb, struct sock *sk,
new->reverse = theirs.reverse;
if (theirs.throughput) {
- if (theirs.throughput < ours->throughput) {
- SOCK_DEBUG(sk, "X.25: throughput negotiated down\n");
- new->throughput = theirs.throughput;
+ int theirs_in = theirs.throughput & 0x0f;
+ int theirs_out = theirs.throughput & 0xf0;
+ int ours_in = ours->throughput & 0x0f;
+ int ours_out = ours->throughput & 0xf0;
+ if (!ours_in || theirs_in < ours_in) {
+ SOCK_DEBUG(sk, "X.25: inbound throughput negotiated\n");
+ new->throughput = (new->throughput & 0xf0) | theirs_in;
+ }
+ if (!ours_out || theirs_out < ours_out) {
+ SOCK_DEBUG(sk,
+ "X.25: outbound throughput negotiated\n");
+ new->throughput = (new->throughput & 0x0f) | theirs_out;
}
}
diff --git a/net/x25/x25_in.c b/net/x25/x25_in.c
index a31b3b9e5966..372ac226e648 100644
--- a/net/x25/x25_in.c
+++ b/net/x25/x25_in.c
@@ -90,6 +90,7 @@ static int x25_queue_rx_frame(struct sock *sk, struct sk_buff *skb, int more)
static int x25_state1_machine(struct sock *sk, struct sk_buff *skb, int frametype)
{
struct x25_address source_addr, dest_addr;
+ int len;
switch (frametype) {
case X25_CALL_ACCEPTED: {
@@ -107,11 +108,17 @@ static int x25_state1_machine(struct sock *sk, struct sk_buff *skb, int frametyp
* Parse the data in the frame.
*/
skb_pull(skb, X25_STD_MIN_LEN);
- skb_pull(skb, x25_addr_ntoa(skb->data, &source_addr, &dest_addr));
- skb_pull(skb,
- x25_parse_facilities(skb, &x25->facilities,
+
+ len = x25_parse_address_block(skb, &source_addr,
+ &dest_addr);
+ if (len > 0)
+ skb_pull(skb, len);
+
+ len = x25_parse_facilities(skb, &x25->facilities,
&x25->dte_facilities,
- &x25->vc_facil_mask));
+ &x25->vc_facil_mask);
+ if (len > 0)
+ skb_pull(skb, len);
/*
* Copy any Call User Data.
*/
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-01 03:53:58 +0000