--- net/x25/x25_facilities.c
+++ net/x25/x25_facilities.c
@@ -35,7 +35,7 @@ int x25_parse_facilities(struct sk_buff
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;
@@ -50,9 +50,19 @@ int x25_parse_facilities(struct sk_buff
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:
+ if (len < 2)
+ return 0;
switch (*p) {
case X25_FAC_REVERSE:
if((p[1] & 0x81) == 0x81) {
@@ -96,6 +106,8 @@ int x25_parse_facilities(struct sk_buff
len -= 2;
break;
case X25_FAC_CLASS_B:
+ if (len < 3)
+ return 0;
switch (*p) {
case X25_FAC_PACKET_SIZE:
facilities->pacsize_in = p[1];
@@ -117,6 +129,8 @@ int x25_parse_facilities(struct sk_buff
len -= 3;
break;
case X25_FAC_CLASS_C:
+ if (len < 4)
+ return 0;
printk(KERN_DEBUG "X.25: unknown facility %02X, "
"values %02X, %02X, %02X\n",
p[0], p[1], p[2], p[3]);
@@ -124,26 +138,26 @@ int x25_parse_facilities(struct sk_buff
len -= 4;
break;
case X25_FAC_CLASS_D:
+ if (len < p[1] + 2)
+ return 0;
switch (*p) {
case X25_FAC_CALLING_AE:
- if (p[1] > X25_MAX_DTE_FACIL_LEN)
- break;
+ if (p[1] > X25_MAX_DTE_FACIL_LEN || p[1] <= 1)
+ return 0;
dte_facs->calling_len = p[2];
memcpy(dte_facs->calling_ae, &p[3], p[1] - 1);
*vc_fac_mask |= X25_MASK_CALLING_AE;
break;
case X25_FAC_CALLED_AE:
- if (p[1] > X25_MAX_DTE_FACIL_LEN)
- break;
+ if (p[1] > X25_MAX_DTE_FACIL_LEN || p[1] <= 1)
+ return 0;
dte_facs->called_len = p[2];
memcpy(dte_facs->called_ae, &p[3], p[1] - 1);
*vc_fac_mask |= X25_MASK_CALLED_AE;
break;
default:
printk(KERN_DEBUG "X.25: unknown facility %02X,"
- "length %d, values %02X, %02X, "
- "%02X, %02X\n",
- p[0], p[1], p[2], p[3], p[4], p[5]);
+ "length %d\n", p[0], p[1]);
break;
}
len -= p[1] + 2;
@@ -247,6 +261,8 @@ int x25_negotiate_facilities(struct sk_b
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.
projects / ziggy471-frankenstein-kernel.git / blobdiff