From: Florian Fainelli Date: Fri, 14 Sep 2012 15:36:38 +0000 (+0000) Subject: busybox: add patch to fix CVE-2011-2716 in udhcp. X-Git-Tag: reboot~12925 X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=93c28ea4737e6bced0245ec4339a8c9494aafae0;p=openwrt%2Fstaging%2Fxback.git busybox: add patch to fix CVE-2011-2716 in udhcp. SVN-Revision: 33404 --- diff --git a/package/busybox/Makefile b/package/busybox/Makefile index 9cb84a19e3..76f52fcd34 100644 --- a/package/busybox/Makefile +++ b/package/busybox/Makefile @@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk PKG_NAME:=busybox PKG_VERSION:=1.19.4 -PKG_RELEASE:=3 +PKG_RELEASE:=4 PKG_FLAGS:=essential PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.bz2 diff --git a/package/busybox/patches/006-upstream_CVE-2011-2716_fixes.patch b/package/busybox/patches/006-upstream_CVE-2011-2716_fixes.patch new file mode 100644 index 0000000000..94d5f34a16 --- /dev/null +++ b/package/busybox/patches/006-upstream_CVE-2011-2716_fixes.patch @@ -0,0 +1,164 @@ +--- busybox-1.19.4/networking/udhcp/common.c ++++ busybox-1.19.4-udhcp/networking/udhcp/common.c +@@ -29,16 +29,16 @@ const struct dhcp_optflag dhcp_optflags[ + // { OPTION_IP | OPTION_LIST , 0x07 }, /* DHCP_LOG_SERVER */ + // { OPTION_IP | OPTION_LIST , 0x08 }, /* DHCP_COOKIE_SERVER */ + { OPTION_IP | OPTION_LIST , 0x09 }, /* DHCP_LPR_SERVER */ +- { OPTION_STRING | OPTION_REQ, 0x0c }, /* DHCP_HOST_NAME */ ++ { OPTION_STRING_HOST | OPTION_REQ, 0x0c }, /* DHCP_HOST_NAME */ + { OPTION_U16 , 0x0d }, /* DHCP_BOOT_SIZE */ +- { OPTION_STRING | OPTION_REQ, 0x0f }, /* DHCP_DOMAIN_NAME */ ++ { OPTION_STRING_HOST | OPTION_REQ, 0x0f }, /* DHCP_DOMAIN_NAME */ + { OPTION_IP , 0x10 }, /* DHCP_SWAP_SERVER */ + { OPTION_STRING , 0x11 }, /* DHCP_ROOT_PATH */ + { OPTION_U8 , 0x17 }, /* DHCP_IP_TTL */ + { OPTION_U16 , 0x1a }, /* DHCP_MTU */ + { OPTION_IP | OPTION_REQ, 0x1c }, /* DHCP_BROADCAST */ + { OPTION_IP_PAIR | OPTION_LIST , 0x21 }, /* DHCP_ROUTES */ +- { OPTION_STRING , 0x28 }, /* DHCP_NIS_DOMAIN */ ++ { OPTION_STRING_HOST , 0x28 }, /* DHCP_NIS_DOMAIN */ + { OPTION_IP | OPTION_LIST , 0x29 }, /* DHCP_NIS_SERVER */ + { OPTION_IP | OPTION_LIST | OPTION_REQ, 0x2a }, /* DHCP_NTP_SERVER */ + { OPTION_IP | OPTION_LIST , 0x2c }, /* DHCP_WINS_SERVER */ +@@ -46,7 +46,7 @@ const struct dhcp_optflag dhcp_optflags[ + { OPTION_IP , 0x36 }, /* DHCP_SERVER_ID */ + { OPTION_STRING , 0x38 }, /* DHCP_ERR_MESSAGE */ + //TODO: must be combined with 'sname' and 'file' handling: +- { OPTION_STRING , 0x42 }, /* DHCP_TFTP_SERVER_NAME */ ++ { OPTION_STRING_HOST , 0x42 }, /* DHCP_TFTP_SERVER_NAME */ + { OPTION_STRING , 0x43 }, /* DHCP_BOOT_FILE */ + //TODO: not a string, but a set of LASCII strings: + // { OPTION_STRING , 0x4D }, /* DHCP_USER_CLASS */ +@@ -143,6 +143,7 @@ const uint8_t dhcp_option_lengths[] ALIG + [OPTION_IP_PAIR] = 8, + // [OPTION_BOOLEAN] = 1, + [OPTION_STRING] = 1, /* ignored by udhcp_str2optset */ ++ [OPTION_STRING_HOST] = 1, /* ignored by udhcp_str2optset */ + #if ENABLE_FEATURE_UDHCP_RFC3397 + [OPTION_DNS_STRING] = 1, /* ignored by both udhcp_str2optset and xmalloc_optname_optval */ + [OPTION_SIP_SERVERS] = 1, +@@ -411,7 +412,9 @@ static NOINLINE void attach_option( + /* actually 255 is ok too, but adding a space can overlow it */ + + existing->data = xrealloc(existing->data, OPT_DATA + 1 + old_len + length); +- if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_STRING) { ++ if ((optflag->flags & OPTION_TYPE_MASK) == OPTION_STRING ++ || (optflag->flags & OPTION_TYPE_MASK) == OPTION_STRING_HOST ++ ) { + /* add space separator between STRING options in a list */ + existing->data[OPT_DATA + old_len] = ' '; + old_len++; +@@ -475,6 +478,7 @@ int FAST_FUNC udhcp_str2optset(const cha + retval = udhcp_str2nip(val, buffer + 4); + break; + case OPTION_STRING: ++ case OPTION_STRING_HOST: + #if ENABLE_FEATURE_UDHCP_RFC3397 + case OPTION_DNS_STRING: + #endif +--- busybox-1.19.4/networking/udhcp/common.h ++++ busybox-1.19.4-udhcp/networking/udhcp/common.h +@@ -80,6 +80,9 @@ enum { + OPTION_IP = 1, + OPTION_IP_PAIR, + OPTION_STRING, ++ /* Opts of STRING_HOST type will be sanitized before they are passed ++ * to udhcpc script's environment: */ ++ OPTION_STRING_HOST, + // OPTION_BOOLEAN, + OPTION_U8, + OPTION_U16, +--- busybox-1.19.4/networking/udhcp/dhcpc.c ++++ busybox-1.19.4-udhcp/networking/udhcp/dhcpc.c +@@ -101,6 +101,7 @@ static const uint8_t len_of_option_as_st + [OPTION_IP_PAIR ] = sizeof("255.255.255.255 ") * 2, + [OPTION_STATIC_ROUTES ] = sizeof("255.255.255.255/32 255.255.255.255 "), + [OPTION_STRING ] = 1, ++ [OPTION_STRING_HOST ] = 1, + #if ENABLE_FEATURE_UDHCP_RFC3397 + [OPTION_DNS_STRING ] = 1, /* unused */ + /* Hmmm, this severely overestimates size if SIP_SERVERS option +@@ -135,6 +136,63 @@ static int mton(uint32_t mask) + return i; + } + ++/* Check if a given label represents a valid DNS label ++ * Return pointer to the first character after the label upon success, ++ * NULL otherwise. ++ * See RFC1035, 2.3.1 ++ */ ++/* We don't need to be particularly anal. For example, allowing _, hyphen ++ * at the end, or leading and trailing dots would be ok, since it ++ * can't be used for attacks. (Leading hyphen can be, if someone uses ++ * cmd "$hostname" ++ * in the script: then hostname may be treated as an option) ++ */ ++static const char *valid_domain_label(const char *label) ++{ ++ unsigned char ch; ++ unsigned pos = 0; ++ ++ for (;;) { ++ ch = *label; ++ if ((ch|0x20) < 'a' || (ch|0x20) > 'z') { ++ if (pos == 0) { ++ /* label must begin with letter */ ++ return NULL; ++ } ++ if (ch < '0' || ch > '9') { ++ if (ch == '\0' || ch == '.') ++ return label; ++ /* DNS allows only '-', but we are more permissive */ ++ if (ch != '-' && ch != '_') ++ return NULL; ++ } ++ } ++ label++; ++ pos++; ++ //Do we want this? ++ //if (pos > 63) /* NS_MAXLABEL; labels must be 63 chars or less */ ++ // return NULL; ++ } ++} ++ ++/* Check if a given name represents a valid DNS name */ ++/* See RFC1035, 2.3.1 */ ++static int good_hostname(const char *name) ++{ ++ //const char *start = name; ++ ++ for (;;) { ++ name = valid_domain_label(name); ++ if (!name) ++ return 0; ++ if (!name[0]) ++ return 1; ++ //Do we want this? ++ //return ((name - start) < 1025); /* NS_MAXDNAME */ ++ name++; ++ } ++} ++ + /* Create "opt_name=opt_value" string */ + static NOINLINE char *xmalloc_optname_optval(uint8_t *option, const struct dhcp_optflag *optflag, const char *opt_name) + { +@@ -185,8 +243,11 @@ static NOINLINE char *xmalloc_optname_op + break; + } + case OPTION_STRING: ++ case OPTION_STRING_HOST: + memcpy(dest, option, len); + dest[len] = '\0'; ++ if (type == OPTION_STRING_HOST && !good_hostname(dest)) ++ safe_strncpy(dest, "bad", len); + return ret; /* Short circuit this case */ + case OPTION_STATIC_ROUTES: { + /* Option binary format: +@@ -314,6 +375,7 @@ static char **fill_envp(struct dhcp_pack + /* +1 element for each option, +2 for subnet option: */ + if (packet) { + /* note: do not search for "pad" (0) and "end" (255) options */ ++//TODO: change logic to scan packet _once_ + for (i = 1; i < 255; i++) { + temp = udhcp_get_option(packet, i); + if (temp) {