Check for invalid pcsc card handle before calling SCardStatus

src/libopensc/reader-pcsc.c

@@ -385,19 +385,20 @@ static int refresh_attributes(sc_reader_t *reader)
  reader->flags |= SC_READER_CARD_PRESENT;
  }
 
- rv = priv->gpriv->SCardStatus(priv->pcsc_card, NULL, &readers_len, &cstate, &prot, atr, &atr_len);
- if (priv->pcsc_card != 0
- && (rv == (LONG)SCARD_W_REMOVED_CARD || rv == (LONG)SCARD_E_INVALID_VALUE || rv == (LONG)SCARD_E_INVALID_HANDLE)) {
+ /* Timeout should denote no change from previous recorded state,
+ * but check for valid card handle */
+ reader->flags &= ~SC_READER_CARD_CHANGED;
+ if (priv->pcsc_card != 0) {
  /* When reader is removed between two subsequent calls to refresh_attributes,
- * SCardGetStatusChange does not notice the change - set it here */
- reader->flags |= SC_READER_CARD_CHANGED;
+ * SCardGetStatusChange does not notice the change, test the card handle with SCardStatus */
+ rv = priv->gpriv->SCardStatus(priv->pcsc_card, NULL, &readers_len, &cstate, &prot, atr, &atr_len);
+
+ if (rv == (LONG)SCARD_W_REMOVED_CARD || rv == (LONG)SCARD_E_INVALID_VALUE || rv == (LONG)SCARD_E_INVALID_HANDLE)
+ reader->flags |= SC_READER_CARD_CHANGED;
  /* If this happens, card must be reconnected, otherwise SCardGetStatusChange() will still return timeout
  * and card handle will be invalid. */
- } else {
- /* Otherwise timeout denotes no change from previous recorded state. Make sure that
- * changed flag is not set. */
- reader->flags &= ~SC_READER_CARD_CHANGED;
  }
+
  LOG_FUNC_RETURN(reader->ctx, SC_SUCCESS);
  }