Fixes the crash reported in Bugzilla #1131 where a malformed parameter that
specifies the table option during a restore can create an invalid pointer.
It was discovered during fuzz testing that options like '-ftf'
can cause a segfault. A parameter that includes a 't' is not currently
filtered correctly.
Improves the filtering to:
Filter a beginning '-' followed by a character other than '-' and then a 't'
anywhere in the parameter. This filters parameters like '-ftf'.
Filter '--t'.
Filter '--table', stopping when the parameter length is reached. Because the
getopt_long function allows abbreviations, any unique abbreviation of '--table'
will be treated as '--table'. This filters parameters like '--t', '--ta', but not
'--ttl' or '--target'.
Signed-off-by: Oliver Ford <ojford@xxxxxxxxx>
---
iptables/ip6tables-restore.c | 6 ++++--
iptables/iptables-restore.c | 6 ++++--
iptables/iptables-xml.c | 7 ++++---
iptables/xtables-restore.c | 6 ++++--
4 files changed, 16 insertions(+), 9 deletions(-)
diff --git a/iptables/ip6tables-restore.c b/iptables/ip6tables-restore.c
index 39a881d..966f189 100644
--- a/iptables/ip6tables-restore.c
+++ b/iptables/ip6tables-restore.c
@@ -165,8 +165,10 @@ static void add_param_to_argv(char *parsestart)
param_buffer[param_len] = '\0';
/* check if table name specified */
- if (!strncmp(param_buffer, "-t", 2)
- || !strncmp(param_buffer, "--table", 8)) {
+ if ((param_buffer[0] == '-' && param_buffer[1] != '-' &&
+ strchr(param_buffer, 't')) ||
+ (!strncmp(param_buffer, "--t", 3)
+ && !strncmp(param_buffer, "--table", strlen(param_buffer)))) {
xtables_error(PARAMETER_PROBLEM,
"The -t option (seen in line %u) cannot be "
"used in ip6tables-restore.\n", line);
diff --git a/iptables/iptables-restore.c b/iptables/iptables-restore.c
index 876fe06..18ea655 100644
--- a/iptables/iptables-restore.c
+++ b/iptables/iptables-restore.c
@@ -162,8 +162,10 @@ static void add_param_to_argv(char *parsestart)
param_buffer[param_len] = '\0';
/* check if table name specified */
- if (!strncmp(param_buffer, "-t", 2)
- || !strncmp(param_buffer, "--table", 8)) {
+ if ((param_buffer[0] == '-' && param_buffer[1] != '-' &&
+ strchr(param_buffer, 't')) ||
+ (!strncmp(param_buffer, "--t", 3)
+ && !strncmp(param_buffer, "--table", strlen(param_buffer)))) {
xtables_error(PARAMETER_PROBLEM,
"The -t option (seen in line %u) cannot be "
"used in iptables-restore.\n", line);
diff --git a/iptables/iptables-xml.c b/iptables/iptables-xml.c
index 2e093b5..05e3bf8 100644
--- a/iptables/iptables-xml.c
+++ b/iptables/iptables-xml.c
@@ -819,9 +819,10 @@ iptables_xml_main(int argc, char *argv[])
*(param_buffer + param_len) = '\0';
/* check if table name specified */
- if (!strncmp(param_buffer, "-t", 3)
- || !strncmp(param_buffer,
- "--table", 8)) {
+ if ((param_buffer[0] == '-' && param_buffer[1] != '-' &&
+ strchr(param_buffer, 't')) ||
+ (!strncmp(param_buffer, "--t", 3)
+ && !strncmp(param_buffer, "--table", strlen(param_buffer)))) {
xtables_error(PARAMETER_PROBLEM,
"Line %u seems to have a "
"-t table option.\n",
diff --git a/iptables/xtables-restore.c b/iptables/xtables-restore.c
index 15824f0..e99231a 100644
--- a/iptables/xtables-restore.c
+++ b/iptables/xtables-restore.c
@@ -136,8 +136,10 @@ static void add_param_to_argv(char *parsestart)
param_buffer[param_len] = '\0';
/* check if table name specified */
- if (!strncmp(param_buffer, "-t", 2)
- || !strncmp(param_buffer, "--table", 8)) {
+ if ((param_buffer[0] == '-' && param_buffer[1] != '-' &&
+ strchr(param_buffer, 't')) ||
+ (!strncmp(param_buffer, "--t", 3)
+ && !strncmp(param_buffer, "--table", strlen(param_buffer)))) {
xtables_error(PARAMETER_PROBLEM,
"The -t option (seen in line %u) cannot be "
"used in xtables-restore.\n", line);
--
2.11.0
--
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