patch 8.0.1467: libvterm doesn't handle illegal byte sequence correctly

Problem:    Libvterm doesn't handle illegal byte sequence correctly.
Solution:   After the invalid code check if there is space to store another
            character.  Allocate one more character. (zhykzhykzhyk, closes
            #2614, closes #2613)

Author: brammool

src/libvterm/src/encoding.c

@@ -46,14 +46,16 @@ static void decode_utf8(VTermEncoding *enc UNUSED, void *data_,
       return;
 
     else if(c >= 0x20 && c < 0x7f) {
-      if(data->bytes_remaining)
+      if(data->bytes_remaining) {
+        data->bytes_remaining = 0;
         cp[(*cpi)++] = UNICODE_INVALID;
-
+	if (*cpi >= cplen)
+	  break;
+      }
       cp[(*cpi)++] = c;
 #ifdef DEBUG_PRINT_UTF8
       printf(" UTF-8 char: U+%04x\n", c);
 #endif
-      data->bytes_remaining = 0;
     }
 
     else if(c == 0x7f) /* DEL */

src/libvterm/src/state.c

@@ -248,8 +248,9 @@ static int on_text(const char bytes[], size_t len, void *user)
 
   VTermPos oldpos = state->pos;
 
-  /* We'll have at most len codepoints */
-  codepoints = vterm_allocator_malloc(state->vt, len * sizeof(uint32_t));
+  /* We'll have at most len codepoints, plus one from a previous incomplete
+   * sequence. */
+  codepoints = vterm_allocator_malloc(state->vt, (len + 1) * sizeof(uint32_t));
 
   encoding =
     state->gsingle_set     ? &state->encoding[state->gsingle_set] :

src/version.c

@@ -771,6 +771,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1467,
 /**/
     1466,
 /**/