More peer review fixes

Author: dgarske

.github/workflows/fuzz.yml

@@ -42,7 +42,7 @@ jobs:
         run: |
           ./autogen.sh
           CC=clang ./configure --enable-wolftpm --enable-pkcallbacks --enable-keygen \
-            CFLAGS="-fsanitize=fuzzer-no-link,address -fno-omit-frame-pointer -g -O1" \
+            CFLAGS="-fsanitize=fuzzer-no-link,address -fno-omit-frame-pointer -g -O1 -DWC_RSA_NO_PADDING" \
             LDFLAGS="-fsanitize=address"
           make -j$(nproc)
           sudo make install

examples/run_examples.sh

@@ -45,8 +45,8 @@ wait_for_port() {
     while [ $elapsed -lt $timeout ]; do
         if command -v ss >/dev/null 2>&1; then
             ss -tln 2>/dev/null | grep -q ":${port} " && return 0
-        elif netstat -tln 2>/dev/null | grep -q ":${port} "; then
-            return 0
+        elif command -v netstat >/dev/null 2>&1; then
+            netstat -tln 2>/dev/null | grep -q ":${port} " && return 0
         fi
         sleep 0.01
         elapsed=$((elapsed + 1))

src/tpm2_swtpm.c

@@ -224,10 +224,11 @@ static TPM_RC SwTpmConnect(TPM2_CTX* ctx, const char* host, const char* port)
     tty.c_oflag &= ~OPOST;
     tty.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
 
-    /* Blocking read with timeout.
+    /* Read with overall timeout.
      * RSA key generation on embedded targets can take 10+ seconds,
-     * so use a generous timeout. */
-    tty.c_cc[VMIN] = 1;    /* block until at least 1 byte */
+     * so use a generous timeout. With VMIN=0 and VTIME>0, read()
+     * returns after the timeout even if no byte is received. */
+    tty.c_cc[VMIN] = 0;    /* allow timeout without requiring first byte */
     tty.c_cc[VTIME] = 200; /* 20 second timeout (tenths of seconds) */
 
     if (tcsetattr(fd, TCSANOW, &tty) != 0) {