From: Dmitry V. Levin <ldv@altlinux.org>
Date: Sun, 23 Dec 2018 22:12:36 +0000 (+0000)
Subject: rtnl_link: fix off-by-one errors in indexed and sorted xlat lookups
X-Git-Tag: v4.26~31
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=d0ae0b3dcabfd61dd2134422114570862fdca283;p=strace

rtnl_link: fix off-by-one errors in indexed and sorted xlat lookups

* rtnl_link.c (decode_nla_tun_type, decode_ifla_xdp_attached,
decode_ifla_inet_conf, decode_ifla_inet6_flags, decode_ifla_inet6_conf,
decode_ifla_inet6_stats, decode_ifla_inet6_icmp6_stats,
decode_ifla_inet6_agm): Decrement xlat size by one to account
for XLAT_END as other users of indexed and sorted xlats do.

Fixes: v4.25~71 "rtnl_link: decode named constants for IFLA_XDP_ATTACHED attribute value"
Fixes: v4.23~41 "rtnl_link: decode IFLA_AF_SPEC"
Fixes: v4.23~37 "rtnl_link: implement IFLA_INFO_DATA for tun devices"
---

diff --git a/rtnl_link.c b/rtnl_link.c
index 7830cd7e..fa6278ef 100644
--- a/rtnl_link.c
+++ b/rtnl_link.c
@@ -338,7 +338,7 @@ decode_nla_tun_type(struct tcb *const tcp,
 {
 	const struct decode_nla_xlat_opts opts = {
 		.xlat = tun_device_types,
-		.xlat_size = ARRAY_SIZE(tun_device_types),
+		.xlat_size = ARRAY_SIZE(tun_device_types) - 1,
 		.xt = XT_INDEXED,
 		.dflt = "IFF_???",
 		.size = 1,
@@ -564,7 +564,7 @@ decode_ifla_xdp_attached(struct tcb *const tcp,
 {
 	const struct decode_nla_xlat_opts opts = {
 		.xlat = rtnl_ifla_xdp_attached_mode,
-		.xlat_size = ARRAY_SIZE(rtnl_ifla_xdp_attached_mode),
+		.xlat_size = ARRAY_SIZE(rtnl_ifla_xdp_attached_mode) - 1,
 		.xt = XT_INDEXED,
 		.dflt = "XDP_ATTACHED_???",
 		.size = 1,
@@ -628,7 +628,8 @@ decode_ifla_inet_conf(struct tcb *const tcp,
 	print_array_ex(tcp, addr, cnt, &elem, sizeof(elem),
 		       tfetch_mem, print_int32_array_member, NULL,
 		       PAF_PRINT_INDICES | PAF_INDEX_XLAT_VALUE_INDEXED
-			| XLAT_STYLE_FMT_D, ARRSZ_PAIR(inet_devconf_indices),
+			| XLAT_STYLE_FMT_D,
+		       ARRSZ_PAIR(inet_devconf_indices) - 1,
 		       "IPV4_DEVCONF_???");
 
 	return true;
@@ -645,7 +646,7 @@ decode_ifla_inet6_flags(struct tcb *const tcp,
 		        const void *const opaque_data)
 {
 	const struct decode_nla_xlat_opts opts = {
-		ARRSZ_PAIR(inet6_if_flags), "IF_???",
+		ARRSZ_PAIR(inet6_if_flags) - 1, "IF_???",
 		.size = 4,
 	};
 
@@ -667,7 +668,8 @@ decode_ifla_inet6_conf(struct tcb *const tcp,
 	print_array_ex(tcp, addr, cnt, &elem, sizeof(elem),
 		       tfetch_mem, print_int32_array_member, NULL,
 		       PAF_PRINT_INDICES | PAF_INDEX_XLAT_VALUE_INDEXED
-			| XLAT_STYLE_FMT_D, ARRSZ_PAIR(inet6_devconf_indices),
+			| XLAT_STYLE_FMT_D,
+		       ARRSZ_PAIR(inet6_devconf_indices) - 1,
 		       "DEVCONF_???");
 
 	return true;
@@ -688,7 +690,7 @@ decode_ifla_inet6_stats(struct tcb *const tcp,
 	print_array_ex(tcp, addr, cnt, &elem, sizeof(elem),
 		       tfetch_mem, print_uint64_array_member, NULL,
 		       PAF_PRINT_INDICES | PAF_INDEX_XLAT_VALUE_INDEXED
-			| XLAT_STYLE_FMT_U, ARRSZ_PAIR(snmp_ip_stats),
+			| XLAT_STYLE_FMT_U, ARRSZ_PAIR(snmp_ip_stats) - 1,
 		       "IPSTATS_MIB_???");
 
 	return true;
@@ -735,7 +737,7 @@ decode_ifla_inet6_icmp6_stats(struct tcb *const tcp,
 	print_array_ex(tcp, addr, cnt, &elem, sizeof(elem),
 		       tfetch_mem, print_uint64_array_member, NULL,
 		       PAF_PRINT_INDICES | PAF_INDEX_XLAT_VALUE_INDEXED
-			| XLAT_STYLE_FMT_U, ARRSZ_PAIR(snmp_icmp6_stats),
+			| XLAT_STYLE_FMT_U, ARRSZ_PAIR(snmp_icmp6_stats) - 1,
 		       "ICMP6_MIB_???");
 
 	return true;
@@ -748,7 +750,7 @@ decode_ifla_inet6_agm(struct tcb *const tcp,
 		      const void *const opaque_data)
 {
 	const struct decode_nla_xlat_opts opts = {
-		ARRSZ_PAIR(in6_addr_gen_mode), "IN6_ADDR_GEN_MODE_???",
+		ARRSZ_PAIR(in6_addr_gen_mode) - 1, "IN6_ADDR_GEN_MODE_???",
 		.xt = XT_INDEXED,
 		.size = 1,
 	};