bind/backport-0006-A6-return-FORMERR-in-fromwire-if-bits-are-non-zero.patch
jiangheng ad37c37958 backport some patches from community
(cherry picked from commit a9fd9ece9b9436b6103d084920c6897ef1adbae6)
2022-09-03 21:36:21 +08:00

34 lines
1.2 KiB
Diff

From 4236972de4c025d5aa1317f782c3df411457b79a Mon Sep 17 00:00:00 2001
From: Mark Andrews <marka@isc.org>
Date: Sat, 15 Aug 2020 10:12:50 +1000
Subject: [PATCH] A6: return FORMERR in fromwire if bits are non zero.
oss_fuzz: Issue 24864: bind9:dns_rdata_fromwire_text_fuzzer: Overwrites-const-input in dns_rdata_fromwire_text_fuzzer
(cherry picked from commit 8452404bd7facb89790c32bab508f55bf8d37cea)
(cherry picked from commit d8a57d32b19942eea923eecfa1bdd863b3286835)
Conflict: NA
Reference: https://gitlab.isc.org/isc-projects/bind9/-/commit/4236972de4c025d5aa1317f782c3df411457b79a
---
lib/dns/rdata/in_1/a6_38.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/lib/dns/rdata/in_1/a6_38.c b/lib/dns/rdata/in_1/a6_38.c
index 1cdbe62d68..e69fc6fbc8 100644
--- a/lib/dns/rdata/in_1/a6_38.c
+++ b/lib/dns/rdata/in_1/a6_38.c
@@ -173,7 +173,9 @@ fromwire_in_a6(ARGS_FROMWIRE) {
if (sr.length < octets)
return (ISC_R_UNEXPECTEDEND);
mask = 0xff >> (prefixlen % 8);
- sr.base[0] &= mask; /* Ensure pad bits are zero. */
+ if ((sr.base[0] & ~mask) != 0) {
+ return (DNS_R_FORMERR);
+ }
RETERR(mem_tobuffer(target, sr.base, octets));
isc_buffer_forward(source, octets);
}
--
2.23.0