Commit 6e7fcff5 authored by Jukka Rissanen's avatar Jukka Rissanen Committed by Benjamin Cabé
Browse files

net: dns: Check DNS answer properly 



The dns_unpack_answer() did not check the length of the message
properly which can cause out of bounds read.

Signed-off-by: default avatarJukka Rissanen <jukka.rissanen@nordicsemi.no>
parent 43c2b9cf

subsys/net/lib/dns/dns_pack.c

+1 −1
Original line number Diff line number Diff line
@@ -134,7 +134,7 @@ int dns_unpack_answer(struct dns_msg_t *dns_msg, int dname_ptr, uint32_t *ttl, 
	 *

	 * See RFC-1035 4.1.3. Resource record format

	 */

	rem_size = dns_msg->msg_size - dname_len;

	rem_size = dns_msg->msg_size - dns_msg->answer_offset - dname_len;

	if (rem_size < 2 + 2 + 4 + 2) {

		return -EINVAL;

	}

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