From: Vladislav Grishenko Date: Fri, 10 Oct 2014 12:18:42 +0000 (+0600) Subject: Fix parsing empty IA_NA, IA_PD and invalid IA_ADDR options X-Git-Tag: debian/1.1+git20160131-1~47^2 X-Git-Url: https://git.decadent.org.uk/gitweb/?a=commitdiff_plain;h=2015de99e2495e886a0e5c748a654d7d5b112cf9;p=odhcp6c.git Fix parsing empty IA_NA, IA_PD and invalid IA_ADDR options --- diff --git a/src/dhcpv6.c b/src/dhcpv6.c index 30c9fb2..ca41db6 100644 --- a/src/dhcpv6.c +++ b/src/dhcpv6.c @@ -693,7 +693,7 @@ static bool dhcpv6_response_is_valid(const void *buf, ssize_t len, rcmsg = odata[0]; } else if ((otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA)) { ia_present = true; - if (olen < sizeof(struct dhcpv6_ia_hdr)) + if (olen < -4 + sizeof(struct dhcpv6_ia_hdr)) options_valid = false; } else if ((otype == DHCPV6_OPT_IA_ADDR) || (otype == DHCPV6_OPT_IA_PREFIX) || @@ -761,7 +761,7 @@ static int dhcpv6_handle_advert(enum dhcpv6_msg orig, const int rc, dhcpv6_for_each_option(opt, end, otype, olen, odata) { if (orig == DHCPV6_MSG_SOLICIT && (otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA) && - olen > sizeof(struct dhcpv6_ia_hdr)) { + olen > -4 + sizeof(struct dhcpv6_ia_hdr)) { struct dhcpv6_ia_hdr *ia_hdr = (void*)(&odata[-4]); dhcpv6_parse_ia(ia_hdr, odata + olen + sizeof(*ia_hdr)); } @@ -800,8 +800,8 @@ static int dhcpv6_handle_advert(enum dhcpv6_msg orig, const int rc, struct dhcpv6_ia_hdr *h = (struct dhcpv6_ia_hdr*)&odata[-4]; uint8_t *oend = odata + olen, *d; dhcpv6_for_each_option(&h[1], oend, otype, olen, d) { - if (otype == DHCPV6_OPT_IA_PREFIX && (olen + 4) >= - (uint16_t)sizeof(struct dhcpv6_ia_prefix)) { + if (otype == DHCPV6_OPT_IA_PREFIX && + olen >= -4 + sizeof(struct dhcpv6_ia_prefix)) { struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&d[-4]; have_pd = p->prefix; } @@ -810,7 +810,8 @@ static int dhcpv6_handle_advert(enum dhcpv6_msg orig, const int rc, struct dhcpv6_ia_hdr *h = (struct dhcpv6_ia_hdr*)&odata[-4]; uint8_t *oend = odata + olen, *d; dhcpv6_for_each_option(&h[1], oend, otype, olen, d) - if (otype == DHCPV6_OPT_IA_ADDR) + if (otype == DHCPV6_OPT_IA_ADDR && + olen >= -4 + sizeof(struct dhcpv6_ia_addr)) have_na = true; } } @@ -930,7 +931,7 @@ static int dhcpv6_handle_reply(enum dhcpv6_msg orig, _unused const int rc, bool passthru = true; if ((otype == DHCPV6_OPT_IA_PD || otype == DHCPV6_OPT_IA_NA) - && olen > sizeof(struct dhcpv6_ia_hdr)) { + && olen > -4 + sizeof(struct dhcpv6_ia_hdr)) { struct dhcpv6_ia_hdr *ia_hdr = (void*)(&odata[-4]); // Test ID