[PATCH] dnsproxy: Address CVE-2025-32366 vulnerability

From: 신윤제(학부생-소프트웨어전공) <[email protected]>

In Connman parse_rr in dnsproxy.c has a memcpy length
that depends on an RR RDLENGTH value (i.e., *rdlen=ntohs(rr->rdlen)
and memcpy(response+offset,*end,*rdlen)). Here, rdlen may be larger
than the amount of remaining packet data in the current state of
parsing. As a result, values of stack memory locations may be sent
over the network in a response.

This patch adds a check to ensure that (*end + *rdlen) does not exceed
the valid range. If the condition is violated, the function returns
-EINVAL.
---
V1->V2:
	- resent using proper inline patch
---
 src/dnsproxy.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/dnsproxy.c b/src/dnsproxy.c
index 7ee26d9f..1dd2f7f5 100644
--- a/src/dnsproxy.c
+++ b/src/dnsproxy.c
@@ -998,6 +998,9 @@ static int parse_rr(const unsigned char *buf, const unsigned char *start,
 	if ((offset + *rdlen) > *response_size)
 		return -ENOBUFS;
 
+	if ((*end + *rdlen) > max)
+		return -EINVAL;
+
 	memcpy(response + offset, *end, *rdlen);
 
 	*end += *rdlen;
-- 
2.43.0