diff mbox series

[v2,2/3] conntrack: fix protocol number parsing

Message ID 20220624150126.24916-3-mikhail.sennikovskii@ionos.com
State Accepted
Delegated to: Pablo Neira
Headers show
Series conntrack: fixes for handling unknown protocols | expand

Commit Message

Mikhail Sennikovsky June 24, 2022, 3:01 p.m. UTC 
Before this commit it was possible to successfully create a ct entry
passing -p 256 and -p some_nonsense.
In both cases an entry with the protocol=0 would be created.

Do not allow invalid protocol values to -p option.
Include testcases covering the issue.

Signed-off-by: Mikhail Sennikovsky <mikhail.sennikovskii@ionos.com>
---
 src/conntrack.c                    | 19 +++++++++++++++++--
 tests/conntrack/testsuite/00create | 10 ++++++++++
 2 files changed, 27 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/src/conntrack.c b/src/conntrack.c
index 500e736..e381543 100644
--- a/src/conntrack.c
+++ b/src/conntrack.c
@@ -882,6 +882,21 @@  static int ct_save_snprintf(char *buf, size_t len,
 
 extern struct ctproto_handler ct_proto_unknown;
 
+static int parse_proto_num(const char *str)
+{
+	char *endptr;
+	long val;
+
+	val = strtol(str, &endptr, 0);
+	if (val >= IPPROTO_MAX ||
+	    val < 0 ||
+	    endptr == str ||
+	    *endptr != '\0')
+		return -1;
+
+	return val;
+}
+
 static struct ctproto_handler *findproto(char *name, int *pnum)
 {
 	struct ctproto_handler *cur;
@@ -901,8 +916,8 @@  static struct ctproto_handler *findproto(char *name, int *pnum)
 		return &ct_proto_unknown;
 	}
 	/* using a protocol number? */
-	protonum = atoi(name);
-	if (protonum >= 0 && protonum <= IPPROTO_MAX) {
+	protonum = parse_proto_num(name);
+	if (protonum >= 0) {
 		/* try lookup by number, perhaps this protocol is supported */
 		list_for_each_entry(cur, &proto_list, head) {
 			if (cur->protonum == protonum) {
diff --git a/tests/conntrack/testsuite/00create b/tests/conntrack/testsuite/00create
index 9962e23..af22f18 100644
--- a/tests/conntrack/testsuite/00create
+++ b/tests/conntrack/testsuite/00create
@@ -61,3 +61,13 @@ 
 -D -s 0.0.0.0 -d 224.0.0.22 -r 224.0.0.22 -q 0.0.0.0 -p 200 ; OK
 # delete again
 -D -s 0.0.0.0 -d 224.0.0.22 -r 224.0.0.22 -q 0.0.0.0 -p 200 ; BAD
+# Invalid protocol values
+# 256 should fail
+-I -t 10 -s 1.1.1.1 -d 2.2.2.2 -r 2.2.2.2 -q 1.1.1.1 -p 256 ; BAD
+# take some invalid protocol name
+-I -t 10 -s 0.0.0.0 -d 224.0.0.22 -r 224.0.0.22 -q 0.0.0.0 -p foo ; BAD
+# take some other invalid protocol values
+-I -t 10 -s 0.0.0.0 -d 224.0.0.22 -r 224.0.0.22 -q 0.0.0.0 -p -10 ; BAD
+-I -t 10 -s 0.0.0.0 -d 224.0.0.22 -r 224.0.0.22 -q 0.0.0.0 -p 2000 ; BAD
+-I -t 10 -s 0.0.0.0 -d 224.0.0.22 -r 224.0.0.22 -q 0.0.0.0 -p 20foo ; BAD
+-I -t 10 -s 0.0.0.0 -d 224.0.0.22 -r 224.0.0.22 -q 0.0.0.0 -p foo20 ; BAD