Alignment problem between 64bit kernel 32bit userspace

Sven-Haegar Koch reported the issue:

sims:~# iptables -A OUTPUT -m set --match-set testset src -j ACCEPT
iptables: Invalid argument. Run `dmesg' for more information.

In syslog:
x_tables: ip_tables: set.3 match: invalid size 48 (kernel) != (user) 32

which was introduced by the counter extension in ipset.

The patch fixes the alignment issue with introducing a new set match
revision with the fixed underlying 'struct ip_set_counter_match'
structure.

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>

1 files changed, 191 insertions, 9 deletions

diff --git a/extensions/libxt_set.c b/extensions/libxt_set.c
index 2cb9e78a..679c04c7 100644
--- a/extensions/libxt_set.c
+++ b/extensions/libxt_set.c
@@ -52,7 +52,7 @@ static int
 set_parse_v0(int c, char **argv, int invert, unsigned int *flags,
 	     const void *entry, struct xt_entry_match **match)
 {
-	struct xt_set_info_match_v0 *myinfo = 
+	struct xt_set_info_match_v0 *myinfo =
 		(struct xt_set_info_match_v0 *) (*match)->data;
 	struct xt_set_info_v0 *info = &myinfo->match_set;
 
@@ -82,7 +82,7 @@ set_parse_v0(int c, char **argv, int invert, unsigned int *flags,
 		parse_dirs_v0(argv[optind], info);
 		DEBUGP("parse: set index %u\n", info->index);
 		optind++;
-		
+
 		*flags = 1;
 		break;
 	}
@@ -132,7 +132,7 @@ static int
 set_parse_v1(int c, char **argv, int invert, unsigned int *flags,
 	     const void *entry, struct xt_entry_match **match)
 {
-	struct xt_set_info_match_v1 *myinfo = 
+	struct xt_set_info_match_v1 *myinfo =
 		(struct xt_set_info_match_v1 *) (*match)->data;
 	struct xt_set_info *info = &myinfo->match_set;
 
@@ -162,7 +162,7 @@ set_parse_v1(int c, char **argv, int invert, unsigned int *flags,
 		parse_dirs(argv[optind], info);
 		DEBUGP("parse: set index %u\n", info->index);
 		optind++;
-		
+
 		*flags = 1;
 		break;
 	}
@@ -227,7 +227,7 @@ static int
 set_parse_v2(int c, char **argv, int invert, unsigned int *flags,
 	     const void *entry, struct xt_entry_match **match)
 {
-	struct xt_set_info_match_v1 *myinfo = 
+	struct xt_set_info_match_v1 *myinfo =
 		(struct xt_set_info_match_v1 *) (*match)->data;
 	struct xt_set_info *info = &myinfo->match_set;
 
@@ -260,7 +260,7 @@ set_parse_v2(int c, char **argv, int invert, unsigned int *flags,
 		parse_dirs(argv[optind], info);
 		DEBUGP("parse: set index %u\n", info->index);
 		optind++;
-		
+
 		*flags = 1;
 		break;
 	}
@@ -334,7 +334,7 @@ static int
 set_parse_v3(int c, char **argv, int invert, unsigned int *flags,
 	     const void *entry, struct xt_entry_match **match)
 {
-	struct xt_set_info_match_v3 *info = 
+	struct xt_set_info_match_v3 *info =
 		(struct xt_set_info_match_v3 *) (*match)->data;
 
 	switch (c) {
@@ -437,7 +437,7 @@ set_parse_v3(int c, char **argv, int invert, unsigned int *flags,
 		parse_dirs(argv[optind], &info->match_set);
 		DEBUGP("parse: set index %u\n", info->match_set.index);
 		optind++;
-		
+
 		*flags = 1;
 		break;
 	}
@@ -446,7 +446,7 @@ set_parse_v3(int c, char **argv, int invert, unsigned int *flags,
 }
 
 static void
-set_printv3_counter(const struct ip_set_counter_match *c, const char *name,
+set_printv3_counter(const struct ip_set_counter_match0 *c, const char *name,
 		    const char *sep)
 {
 	switch (c->op) {
@@ -497,6 +497,174 @@ set_save_v3(const void *ip, const struct xt_entry_match *match)
 	set_print_v3_matchinfo(info, "--match-set", "--");
 }
 
+/* Revision 4 */
+static int
+set_parse_v4(int c, char **argv, int invert, unsigned int *flags,
+	     const void *entry, struct xt_entry_match **match)
+{
+	struct xt_set_info_match_v4 *info =
+		(struct xt_set_info_match_v4 *) (*match)->data;
+
+	switch (c) {
+	case 'a':
+		if (invert)
+			info->flags |= IPSET_FLAG_SKIP_SUBCOUNTER_UPDATE;
+		break;
+	case '0':
+		if (info->bytes.op != IPSET_COUNTER_NONE)
+			xtables_error(PARAMETER_PROBLEM,
+				      "only one of the --bytes-[eq|lt|gt]"
+				      " is allowed\n");
+		if (invert)
+			xtables_error(PARAMETER_PROBLEM,
+				      "--bytes-gt option cannot be inverted\n");
+		info->bytes.op = IPSET_COUNTER_GT;
+		info->bytes.value = parse_counter(optarg);
+		break;
+	case '9':
+		if (info->bytes.op != IPSET_COUNTER_NONE)
+			xtables_error(PARAMETER_PROBLEM,
+				      "only one of the --bytes-[eq|lt|gt]"
+				      " is allowed\n");
+		if (invert)
+			xtables_error(PARAMETER_PROBLEM,
+				      "--bytes-lt option cannot be inverted\n");
+		info->bytes.op = IPSET_COUNTER_LT;
+		info->bytes.value = parse_counter(optarg);
+		break;
+	case '8':
+		if (info->bytes.op != IPSET_COUNTER_NONE)
+			xtables_error(PARAMETER_PROBLEM,
+				      "only one of the --bytes-[eq|lt|gt]"
+				      " is allowed\n");
+		info->bytes.op = invert ? IPSET_COUNTER_NE : IPSET_COUNTER_EQ;
+		info->bytes.value = parse_counter(optarg);
+		break;
+	case '7':
+		if (info->packets.op != IPSET_COUNTER_NONE)
+			xtables_error(PARAMETER_PROBLEM,
+				      "only one of the --packets-[eq|lt|gt]"
+				      " is allowed\n");
+		if (invert)
+			xtables_error(PARAMETER_PROBLEM,
+				      "--packets-gt option cannot be inverted\n");
+		info->packets.op = IPSET_COUNTER_GT;
+		info->packets.value = parse_counter(optarg);
+		break;
+	case '6':
+		if (info->packets.op != IPSET_COUNTER_NONE)
+			xtables_error(PARAMETER_PROBLEM,
+				      "only one of the --packets-[eq|lt|gt]"
+				      " is allowed\n");
+		if (invert)
+			xtables_error(PARAMETER_PROBLEM,
+				      "--packets-lt option cannot be inverted\n");
+		info->packets.op = IPSET_COUNTER_LT;
+		info->packets.value = parse_counter(optarg);
+		break;
+	case '5':
+		if (info->packets.op != IPSET_COUNTER_NONE)
+			xtables_error(PARAMETER_PROBLEM,
+				      "only one of the --packets-[eq|lt|gt]"
+				      " is allowed\n");
+		info->packets.op = invert ? IPSET_COUNTER_NE : IPSET_COUNTER_EQ;
+		info->packets.value = parse_counter(optarg);
+		break;
+	case '4':
+		if (invert)
+			info->flags |= IPSET_FLAG_SKIP_COUNTER_UPDATE;
+		break;
+	case '3':
+		if (invert)
+			xtables_error(PARAMETER_PROBLEM,
+				      "--return-nomatch flag cannot be inverted\n");
+		info->flags |= IPSET_FLAG_RETURN_NOMATCH;
+		break;
+	case '2':
+		fprintf(stderr,
+			"--set option deprecated, please use --match-set\n");
+	case '1':		/* --match-set <set> <flag>[,<flag> */
+		if (info->match_set.dim)
+			xtables_error(PARAMETER_PROBLEM,
+				      "--match-set can be specified only once");
+		if (invert)
+			info->match_set.flags |= IPSET_INV_MATCH;
+
+		if (!argv[optind]
+		    || argv[optind][0] == '-'
+		    || argv[optind][0] == '!')
+			xtables_error(PARAMETER_PROBLEM,
+				      "--match-set requires two args.");
+
+		if (strlen(optarg) > IPSET_MAXNAMELEN - 1)
+			xtables_error(PARAMETER_PROBLEM,
+				      "setname `%s' too long, max %d characters.",
+				      optarg, IPSET_MAXNAMELEN - 1);
+
+		get_set_byname(optarg, &info->match_set);
+		parse_dirs(argv[optind], &info->match_set);
+		DEBUGP("parse: set index %u\n", info->match_set.index);
+		optind++;
+
+		*flags = 1;
+		break;
+	}
+
+	return 1;
+}
+
+static void
+set_printv4_counter(const struct ip_set_counter_match *c, const char *name,
+		    const char *sep)
+{
+	switch (c->op) {
+	case IPSET_COUNTER_EQ:
+		printf(" %s%s-eq %llu", sep, name, c->value);
+		break;
+	case IPSET_COUNTER_NE:
+		printf(" ! %s%s-eq %llu", sep, name, c->value);
+		break;
+	case IPSET_COUNTER_LT:
+		printf(" %s%s-lt %llu", sep, name, c->value);
+		break;
+	case IPSET_COUNTER_GT:
+		printf(" %s%s-gt %llu", sep, name, c->value);
+		break;
+	}
+}
+
+static void
+set_print_v4_matchinfo(const struct xt_set_info_match_v4 *info,
+		       const char *opt, const char *sep)
+{
+	print_match(opt, &info->match_set);
+	if (info->flags & IPSET_FLAG_RETURN_NOMATCH)
+		printf(" %sreturn-nomatch", sep);
+	if ((info->flags & IPSET_FLAG_SKIP_COUNTER_UPDATE))
+		printf(" ! %supdate-counters", sep);
+	if ((info->flags & IPSET_FLAG_SKIP_SUBCOUNTER_UPDATE))
+		printf(" ! %supdate-subcounters", sep);
+	set_printv4_counter(&info->packets, "packets", sep);
+	set_printv4_counter(&info->bytes, "bytes", sep);
+}
+
+/* Prints out the matchinfo. */
+static void
+set_print_v4(const void *ip, const struct xt_entry_match *match, int numeric)
+{
+	const struct xt_set_info_match_v4 *info = (const void *)match->data;
+
+	set_print_v4_matchinfo(info, "match-set", "");
+}
+
+static void
+set_save_v4(const void *ip, const struct xt_entry_match *match)
+{
+	const struct xt_set_info_match_v4 *info = (const void *)match->data;
+
+	set_print_v4_matchinfo(info, "--match-set", "--");
+}
+
 static struct xtables_match set_mt_reg[] = {
 	{
 		.name		= "set",
@@ -554,6 +722,20 @@ static struct xtables_match set_mt_reg[] = {
 		.save		= set_save_v3,
 		.extra_opts	= set_opts_v3,
 	},
+	{
+		.name		= "set",
+		.revision	= 4,
+		.version	= XTABLES_VERSION,
+		.family		= NFPROTO_UNSPEC,
+		.size		= XT_ALIGN(sizeof(struct xt_set_info_match_v4)),
+		.userspacesize	= XT_ALIGN(sizeof(struct xt_set_info_match_v4)),
+		.help		= set_help_v3,
+		.parse		= set_parse_v4,
+		.final_check	= set_check_v0,
+		.print		= set_print_v4,
+		.save		= set_save_v4,
+		.extra_opts	= set_opts_v3,
+	},
 };
 
 void _init(void)