diff --git a/src/audio.c b/src/audio.c
index 8b927ea..3cd2cd0 100644
--- a/src/audio.c
+++ b/src/audio.c
@@ -32,9 +32,12 @@ int audio_init(audio_t *aud, int channels, int sample_rate, int frame_size) {
 
     aud->buffer_size = frame_size * channels;
     aud->buffer = (audio_sample_t *)malloc(aud->buffer_size * sizeof(audio_sample_t));
+    if (aud->buffer == NULL)
+        return -1;
 
     if ((pa_err = Pa_StartStream(aud->stream)) != paNoError) {
         fprintf(stderr, "Cannot start a PortAudio stream: %s\n", Pa_GetErrorText(pa_err));
+        free(aud->buffer);
         return -1;
     }
 
diff --git a/src/crypt.c b/src/crypt.c
index d134119..220b92c 100644
--- a/src/crypt.c
+++ b/src/crypt.c
@@ -105,12 +105,16 @@ int crypt_store_key(const crypt_key_t *const k, FILE *const pub, FILE *const sec
 
 unsigned char *crypt_hello(const crypt_key_t *const own) {
     unsigned char *hello = (unsigned char *)malloc(CRYPT_HELLO_LEN * sizeof(unsigned char));
+    if (hello == NULL)
+        return NULL;
 
     if (crypt_key_export_public(own, (char *const)hello) == -1) {
+        free(hello);
         return NULL;
     }
 
     if (crypto_sign_detached(hello+CRYPT_PKEY_HEXLEN, NULL, (const unsigned char *)hello, CRYPT_PKEY_HEXLEN, own->sign_sec) == -1) {
+        free(hello);
         return NULL;
     }
 
@@ -167,8 +171,11 @@ int crypt_session_init(crypt_session_t *const s, const crypt_key_t *const own, c
 
 unsigned char *crypt_session_encrypt(crypt_session_t *const s, const unsigned char *const m, unsigned long long mlen, unsigned long long *clen) {
     unsigned char *c = (unsigned char *)malloc((mlen + crypto_aead_aegis256_ABYTES) * sizeof(unsigned char));
+    if (c == NULL)
+        return NULL;
 
     if (crypto_aead_aegis256_encrypt(c, clen, m, mlen, NULL, 0, NULL, s->nonce, s->tx) == -1) {
+        free(c);
         return NULL;
     }