From: Sean Edmond seanedmond@microsoft.com
RFC 5970 states that OPT_BOOTFILE_PARAM (option 60) can be multiple parameters that start with a 16-bit length field followed by the parameter. For example: [ param-len 1 (16-bits) ] [ parameter 1 (variable length) ]
This fix ensure we're considering "param-len 1" in the parsing.
Signed-off-by: Sean Edmond seanedmond@microsoft.com --- net/dhcpv6.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/net/dhcpv6.c b/net/dhcpv6.c index 73a1067877..4aea779f6f 100644 --- a/net/dhcpv6.c +++ b/net/dhcpv6.c @@ -304,7 +304,7 @@ static void dhcp6_parse_ia_options(struct dhcp6_option_hdr *ia_ptr, uchar *ia_op static void dhcp6_parse_options(uchar *rx_pkt, unsigned int len) { uchar *option_ptr; - int sol_max_rt_sec, option_len; + int sol_max_rt_sec, option_len, param_len_1; char *s, *e; struct dhcp6_option_hdr *option_hdr;
@@ -390,14 +390,23 @@ static void dhcp6_parse_options(uchar *rx_pkt, unsigned int len) case DHCP6_OPTION_OPT_BOOTFILE_PARAM: if (IS_ENABLED(CONFIG_DHCP6_PXE_DHCP_OPTION)) { debug("DHCP6_OPTION_OPT_BOOTFILE_PARAM FOUND\n"); + /* if CONFIG_DHCP6_PXE_DHCP_OPTION is set the PXE config file path + * is contained in the first OPT_BOOTFILE_PARAM argument + */ + param_len_1 = ntohs(*((u16 *)option_ptr)); + option_ptr += sizeof(u16); + if (param_len_1 + sizeof(u16) > option_len) { + debug("Invalid BOOTFILE_PARAM param_len_1. Skipping\n"); + break; + }
if (pxelinux_configfile) free(pxelinux_configfile);
- pxelinux_configfile = (char *)malloc((option_len + 1) * + pxelinux_configfile = (char *)malloc((param_len_1 + 1) * sizeof(char)); if (pxelinux_configfile) - strlcpy(pxelinux_configfile, option_ptr, option_len + 1); + strlcpy(pxelinux_configfile, option_ptr, param_len_1 + 1); else printf("Error: Failed to allocate pxelinux_configfile\n");