1 files changed, 25 insertions, 0 deletions
diff --git a/src/fuzz/fuzz-dns-packet.c b/src/fuzz/fuzz-dns-packet.c
new file mode 100644
index 0000000..b9a0aa1
--- /dev/null
+++ b/src/fuzz/fuzz-dns-packet.c
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "fuzz.h"
+#include "memory-util.h"
+#include "resolved-dns-packet.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+        _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
+
+        if (size > DNS_PACKET_SIZE_MAX)
+                return 0;
+
+        assert_se(dns_packet_new(&p, DNS_PROTOCOL_DNS, 0, DNS_PACKET_SIZE_MAX) >= 0);
+        p->size = 0; /* by default append starts after the header, undo that */
+        assert_se(dns_packet_append_blob(p, data, size, NULL) >= 0);
+        if (size < DNS_PACKET_HEADER_SIZE) {
+                /* make sure we pad the packet back up to the minimum header size */
+                assert_se(p->allocated >= DNS_PACKET_HEADER_SIZE);
+                memzero(DNS_PACKET_DATA(p) + size, DNS_PACKET_HEADER_SIZE - size);
+                p->size = DNS_PACKET_HEADER_SIZE;
+        }
+        (void) dns_packet_extract(p);
+
+        return 0;
+}