Check destination buffer size on read()

Author: mchack-work

include/tkey/proto.h

@@ -39,6 +39,5 @@ int parseframe(uint8_t b, struct frame_header *hdr);
 void writebyte(uint8_t b);
 void write(const uint8_t *buf, size_t nbytes);
 uint8_t readbyte();
-void read(uint8_t *buf, size_t nbytes);
-
+int read(uint8_t *buf, size_t bufsize, size_t nbytes);
 #endif

libcommon/proto.c

@@ -82,9 +82,15 @@ uint8_t readbyte()
 	}
 }
 
-void read(uint8_t *buf, size_t nbytes)
+int read(uint8_t *buf, size_t bufsize, size_t nbytes)
 {
+	if (nbytes > bufsize) {
+		return -1;
+	}
+
 	for (int n = 0; n < nbytes; n++) {
 		buf[n] = readbyte();
 	}
+
+	return 0;
 }