From 247932f367f856e7ce91528e14f0aaf838150857 Mon Sep 17 00:00:00 2001 From: NIIBE Yutaka Date: Tue, 25 Apr 2017 21:00:41 +0900 Subject: [PATCH] dirmngr: Fix aliasing problem in dns.c. * dirmngr/dns.c (dns_ai_setent): Care about aliasing. -- Co-authored-by: Tomas Mraz GnuPG-bug-id: 3105 Signed-off-by: NIIBE Yutaka --- dirmngr/dns.c | 34 ++++++++++++++++++---------------- 1 file changed, 18 insertions(+), 16 deletions(-) diff --git a/dirmngr/dns.c b/dirmngr/dns.c index 7a6202fe0..5b8f14ff8 100644 --- a/dirmngr/dns.c +++ b/dirmngr/dns.c @@ -9456,29 +9456,31 @@ void dns_ai_close(struct dns_addrinfo *ai) { static int dns_ai_setent(struct addrinfo **ent, union dns_any *any, enum dns_type type, struct dns_addrinfo *ai) { - struct sockaddr *saddr; - struct sockaddr_in sin; - struct sockaddr_in6 sin6; + union u { + struct sockaddr_in sin; + struct sockaddr_in6 sin6; + struct sockaddr_storage ss; + } addr; const char *cname; size_t clen; switch (type) { case DNS_T_A: - saddr = memset(&sin, '\0', sizeof sin); + memset(&addr.sin, '\0', sizeof addr.sin); - sin.sin_family = AF_INET; - sin.sin_port = htons(ai->port); + addr.sin.sin_family = AF_INET; + addr.sin.sin_port = htons(ai->port); - memcpy(&sin.sin_addr, any, sizeof sin.sin_addr); + memcpy(&addr.sin.sin_addr, any, sizeof addr.sin.sin_addr); break; case DNS_T_AAAA: - saddr = memset(&sin6, '\0', sizeof sin6); + memset(&addr.sin6, '\0', sizeof addr.sin6); - sin6.sin6_family = AF_INET6; - sin6.sin6_port = htons(ai->port); + addr.sin6.sin6_family = AF_INET6; + addr.sin6.sin6_port = htons(ai->port); - memcpy(&sin6.sin6_addr, any, sizeof sin6.sin6_addr); + memcpy(&addr.sin6.sin6_addr, any, sizeof addr.sin6.sin6_addr); break; default: @@ -9493,20 +9495,20 @@ static int dns_ai_setent(struct addrinfo **ent, union dns_any *any, enum dns_typ clen = 0; } - if (!(*ent = malloc(sizeof **ent + dns_sa_len(saddr) + ((ai->hints.ai_flags & AI_CANONNAME)? clen + 1 : 0)))) + if (!(*ent = malloc(sizeof **ent + dns_sa_len(&addr) + ((ai->hints.ai_flags & AI_CANONNAME)? clen + 1 : 0)))) return dns_syerr(); memset(*ent, '\0', sizeof **ent); - (*ent)->ai_family = saddr->sa_family; + (*ent)->ai_family = addr.ss.ss_family; (*ent)->ai_socktype = ai->hints.ai_socktype; (*ent)->ai_protocol = ai->hints.ai_protocol; - (*ent)->ai_addr = memcpy((unsigned char *)*ent + sizeof **ent, saddr, dns_sa_len(saddr)); - (*ent)->ai_addrlen = dns_sa_len(saddr); + (*ent)->ai_addr = memcpy((unsigned char *)*ent + sizeof **ent, &addr, dns_sa_len(&addr)); + (*ent)->ai_addrlen = dns_sa_len(&addr); if (ai->hints.ai_flags & AI_CANONNAME) - (*ent)->ai_canonname = memcpy((unsigned char *)*ent + sizeof **ent + dns_sa_len(saddr), cname, clen + 1); + (*ent)->ai_canonname = memcpy((unsigned char *)*ent + sizeof **ent + dns_sa_len(&addr), cname, clen + 1); ai->found++;