Merge pull request #3925 from authmillenon/gnrc_pktbuf_static/fix/sho…

…rt_snip gnrc_pktbuf_static: fix marking of pktsnips with short payload
RIOT-OS · Sep 22, 2015 · 8df17de · 8df17de
2 parents 1f02e7c + e5c6e3d
commit 8df17de
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Showing 2 changed files with 18 additions and 1 deletion.
diff --git a/sys/net/gnrc/pktbuf_static/gnrc_pktbuf_static.c b/sys/net/gnrc/pktbuf_static/gnrc_pktbuf_static.c
@@ -113,7 +113,8 @@ gnrc_pktsnip_t *gnrc_pktbuf_mark(gnrc_pktsnip_t *pkt, size_t size, gnrc_nettype_
         mutex_unlock(&_mutex);
         return NULL;
     }
-    if (size < required_new_size) { /* would not fit unused marker => move data around */
+    /* would not fit unused marker => move data around */
+    if ((size < required_new_size) || ((pkt->size - size) < sizeof(_unused_t))) {
         void *new_data_marked, *new_data_rest;
         new_data_marked = _pktbuf_alloc(size);
         if (new_data_marked == NULL) {

diff --git a/tests/unittests/tests-pktbuf/tests-pktbuf.c b/tests/unittests/tests-pktbuf/tests-pktbuf.c
@@ -574,6 +574,21 @@ static void test_pktbuf_hold__success2(void)
     TEST_ASSERT_EQUAL_INT(TEST_UINT8 + 1, pkt->users);
 }
 
+static void test_pktbuf_release__short_pktsnips(void)
+{
+    gnrc_pktsnip_t *pkt = gnrc_pktbuf_add(NULL, TEST_STRING8, sizeof(TEST_STRING8),
+                                          GNRC_NETTYPE_UNDEF);
+    gnrc_pktsnip_t *hdr = gnrc_pktbuf_mark(pkt, sizeof(TEST_STRING8) - 1, GNRC_NETTYPE_TEST);
+    TEST_ASSERT(pkt);
+    TEST_ASSERT(hdr);
+    TEST_ASSERT(pkt->next == hdr);
+    TEST_ASSERT(hdr->next == NULL);
+    TEST_ASSERT_EQUAL_INT(hdr->size, sizeof(TEST_STRING8) - 1);
+    TEST_ASSERT_EQUAL_INT(pkt->size, 1);
+    gnrc_pktbuf_release(pkt);
+    TEST_ASSERT(gnrc_pktbuf_is_empty());
+}
+
 static void test_pktbuf_release__success(void)
 {
     gnrc_pktsnip_t *pkt = gnrc_pktbuf_add(NULL, TEST_STRING16, sizeof(TEST_STRING16),
@@ -722,6 +737,7 @@ Test *tests_pktbuf_tests(void)
         new_TestFixture(test_pktbuf_hold__pkt_external),
         new_TestFixture(test_pktbuf_hold__success),
         new_TestFixture(test_pktbuf_hold__success2),
+        new_TestFixture(test_pktbuf_release__short_pktsnips),
         new_TestFixture(test_pktbuf_release__success),
         new_TestFixture(test_pktbuf_start_write__NULL),
         new_TestFixture(test_pktbuf_start_write__pkt_users_1),