From e0bccd315db0c2f919e7fcf9cb60db21d9986f52 Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Sun, 20 Mar 2011 06:48:05 +0000 Subject: rose: Add length checks to CALL_REQUEST parsing Define some constant offsets for CALL_REQUEST based on the description at and the definition of ROSE as using 10-digit (5-byte) addresses. Use them consistently. Validate all implicit and explicit facilities lengths. Validate the address length byte rather than either trusting or assuming its value. Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller --- net/rose/rose_loopback.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) (limited to 'net/rose/rose_loopback.c') diff --git a/net/rose/rose_loopback.c b/net/rose/rose_loopback.c index ae4a9d99aec7..344456206b70 100644 --- a/net/rose/rose_loopback.c +++ b/net/rose/rose_loopback.c @@ -73,9 +73,20 @@ static void rose_loopback_timer(unsigned long param) unsigned int lci_i, lci_o; while ((skb = skb_dequeue(&loopback_queue)) != NULL) { + if (skb->len < ROSE_MIN_LEN) { + kfree_skb(skb); + continue; + } lci_i = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF); frametype = skb->data[2]; - dest = (rose_address *)(skb->data + 4); + if (frametype == ROSE_CALL_REQUEST && + (skb->len <= ROSE_CALL_REQ_FACILITIES_OFF || + skb->data[ROSE_CALL_REQ_ADDR_LEN_OFF] != + ROSE_CALL_REQ_ADDR_LEN_VAL)) { + kfree_skb(skb); + continue; + } + dest = (rose_address *)(skb->data + ROSE_CALL_REQ_DEST_ADDR_OFF); lci_o = ROSE_DEFAULT_MAXVC + 1 - lci_i; skb_reset_transport_header(skb); -- cgit v1.2.3