From f99add3d5b8d23e7a8f9bd3520ccb518ca40b253 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Manuel=20Sch=C3=B6lling?= Date: Sat, 31 May 2014 23:37:40 +0200 Subject: [PATCH] dns_resolver: Do not accept domain names longer than 255 chars MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit According to RFC1035 "[...] the total length of a domain name (i.e., label octets and label length octets) is restricted to 255 octets or less." Signed-off-by: Manuel Schölling Signed-off-by: David S. Miller --- net/dns_resolver/dns_query.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/dns_resolver/dns_query.c b/net/dns_resolver/dns_query.c index 2022b46ab38f..e9ca993549a4 100644 --- a/net/dns_resolver/dns_query.c +++ b/net/dns_resolver/dns_query.c @@ -94,8 +94,8 @@ int dns_query(const char *type, const char *name, size_t namelen, } if (!namelen) - namelen = strlen(name); - if (namelen < 3) + namelen = strnlen(name, 256); + if (namelen < 3 || namelen > 255) return -EINVAL; desclen += namelen + 1;