From 894c7b77081e8eba8d78722624cc145f87ae95ac Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Tue, 10 Nov 2020 14:52:25 +0100 Subject: [PATCH] resolved: gracefully handle trailing packet garbage Similar to the previous commit: if we see trailing garbage in a DNS packet, let's assume EDNS is borked too, and suppress it. --- src/resolve/resolved-dns-packet.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/src/resolve/resolved-dns-packet.c b/src/resolve/resolved-dns-packet.c index 953d5fa337d..f548bbf9f25 100644 --- a/src/resolve/resolved-dns-packet.c +++ b/src/resolve/resolved-dns-packet.c @@ -2394,6 +2394,12 @@ int dns_packet_extract(DnsPacket *p) { if (r < 0) return r; + if (p->rindex < p->size) { + log_debug("Trailing garbage in packet, suppressing OPT."); + p->opt = dns_resource_record_unref(p->opt); + p->opt_start = p->opt_size = SIZE_MAX; + } + p->question = TAKE_PTR(question); p->answer = TAKE_PTR(answer); -- 2.47.3