diff options
Diffstat (limited to 'main/busybox/CVE-2018-20679.patch')
| -rw-r--r-- | main/busybox/CVE-2018-20679.patch | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/main/busybox/CVE-2018-20679.patch b/main/busybox/CVE-2018-20679.patch new file mode 100644 index 0000000000..bc1a48bf4b --- /dev/null +++ b/main/busybox/CVE-2018-20679.patch @@ -0,0 +1,136 @@ +From 6d3b4bb24da9a07c263f3c1acf8df85382ff562c Mon Sep 17 00:00:00 2001 +From: Denys Vlasenko <vda.linux@googlemail.com> +Date: Mon, 17 Dec 2018 18:07:18 +0100 +Subject: udhcpc: check that 4-byte options are indeed 4-byte, closes 11506 + +function old new delta +udhcp_get_option32 - 27 +27 +udhcp_get_option 231 248 +17 +------------------------------------------------------------------------------ +(add/remove: 1/0 grow/shrink: 1/0 up/down: 44/0) Total: 44 bytes + +Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com> +--- + networking/udhcp/common.c | 19 +++++++++++++++++++ + networking/udhcp/common.h | 4 ++++ + networking/udhcp/dhcpc.c | 6 +++--- + networking/udhcp/dhcpd.c | 6 +++--- + 4 files changed, 29 insertions(+), 6 deletions(-) + +diff --git a/networking/udhcp/common.c b/networking/udhcp/common.c +index e5fd74f91..41b05b855 100644 +--- a/networking/udhcp/common.c ++++ b/networking/udhcp/common.c +@@ -272,6 +272,15 @@ uint8_t* FAST_FUNC udhcp_get_option(struct dhcp_packet *packet, int code) + goto complain; /* complain and return NULL */ + + if (optionptr[OPT_CODE] == code) { ++ if (optionptr[OPT_LEN] == 0) { ++ /* So far no valid option with length 0 known. ++ * Having this check means that searching ++ * for DHCP_MESSAGE_TYPE need not worry ++ * that returned pointer might be unsafe ++ * to dereference. ++ */ ++ goto complain; /* complain and return NULL */ ++ } + log_option("option found", optionptr); + return optionptr + OPT_DATA; + } +@@ -289,6 +298,16 @@ uint8_t* FAST_FUNC udhcp_get_option(struct dhcp_packet *packet, int code) + return NULL; + } + ++uint8_t* FAST_FUNC udhcp_get_option32(struct dhcp_packet *packet, int code) ++{ ++ uint8_t *r = udhcp_get_option(packet, code); ++ if (r) { ++ if (r[-1] != 4) ++ r = NULL; ++ } ++ return r; ++} ++ + /* Return the position of the 'end' option (no bounds checking) */ + int FAST_FUNC udhcp_end_option(uint8_t *optionptr) + { +diff --git a/networking/udhcp/common.h b/networking/udhcp/common.h +index 7ad603d33..9511152ff 100644 +--- a/networking/udhcp/common.h ++++ b/networking/udhcp/common.h +@@ -205,6 +205,10 @@ extern const uint8_t dhcp_option_lengths[] ALIGN1; + unsigned FAST_FUNC udhcp_option_idx(const char *name, const char *option_strings); + + uint8_t *udhcp_get_option(struct dhcp_packet *packet, int code) FAST_FUNC; ++/* Same as above + ensures that option length is 4 bytes ++ * (returns NULL if size is different) ++ */ ++uint8_t *udhcp_get_option32(struct dhcp_packet *packet, int code) FAST_FUNC; + int udhcp_end_option(uint8_t *optionptr) FAST_FUNC; + void udhcp_add_binary_option(struct dhcp_packet *packet, uint8_t *addopt) FAST_FUNC; + #if ENABLE_UDHCPC || ENABLE_UDHCPD +diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c +index 4b23e4d39..5b3fd531c 100644 +--- a/networking/udhcp/dhcpc.c ++++ b/networking/udhcp/dhcpc.c +@@ -1691,7 +1691,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv) + * They say ISC DHCP client supports this case. + */ + server_addr = 0; +- temp = udhcp_get_option(&packet, DHCP_SERVER_ID); ++ temp = udhcp_get_option32(&packet, DHCP_SERVER_ID); + if (!temp) { + bb_error_msg("no server ID, using 0.0.0.0"); + } else { +@@ -1718,7 +1718,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv) + struct in_addr temp_addr; + uint8_t *temp; + +- temp = udhcp_get_option(&packet, DHCP_LEASE_TIME); ++ temp = udhcp_get_option32(&packet, DHCP_LEASE_TIME); + if (!temp) { + bb_error_msg("no lease time with ACK, using 1 hour lease"); + lease_seconds = 60 * 60; +@@ -1813,7 +1813,7 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv) + uint32_t svid; + uint8_t *temp; + +- temp = udhcp_get_option(&packet, DHCP_SERVER_ID); ++ temp = udhcp_get_option32(&packet, DHCP_SERVER_ID); + if (!temp) { + non_matching_svid: + log1("received DHCP NAK with wrong" +diff --git a/networking/udhcp/dhcpd.c b/networking/udhcp/dhcpd.c +index a8cd3f03b..477856d11 100644 +--- a/networking/udhcp/dhcpd.c ++++ b/networking/udhcp/dhcpd.c +@@ -640,7 +640,7 @@ static void add_server_options(struct dhcp_packet *packet) + static uint32_t select_lease_time(struct dhcp_packet *packet) + { + uint32_t lease_time_sec = server_config.max_lease_sec; +- uint8_t *lease_time_opt = udhcp_get_option(packet, DHCP_LEASE_TIME); ++ uint8_t *lease_time_opt = udhcp_get_option32(packet, DHCP_LEASE_TIME); + if (lease_time_opt) { + move_from_unaligned32(lease_time_sec, lease_time_opt); + lease_time_sec = ntohl(lease_time_sec); +@@ -987,7 +987,7 @@ int udhcpd_main(int argc UNUSED_PARAM, char **argv) + } + + /* Get SERVER_ID if present */ +- server_id_opt = udhcp_get_option(&packet, DHCP_SERVER_ID); ++ server_id_opt = udhcp_get_option32(&packet, DHCP_SERVER_ID); + if (server_id_opt) { + uint32_t server_id_network_order; + move_from_unaligned32(server_id_network_order, server_id_opt); +@@ -1011,7 +1011,7 @@ int udhcpd_main(int argc UNUSED_PARAM, char **argv) + } + + /* Get REQUESTED_IP if present */ +- requested_ip_opt = udhcp_get_option(&packet, DHCP_REQUESTED_IP); ++ requested_ip_opt = udhcp_get_option32(&packet, DHCP_REQUESTED_IP); + if (requested_ip_opt) { + move_from_unaligned32(requested_nip, requested_ip_opt); + } +-- +cgit v1.2.1 + |