From: Dominik Csapak <d.csapak@proxmox.com>
Date: Tue, 28 Feb 2017 11:06:43 +0000 (+0100)
Subject: bound check utf8 characters
X-Git-Url: https://git.proxmox.com/?p=vncterm.git;a=commitdiff_plain;h=3d0dbf7c0e96b949d1f682bc02ce9500c136ae18;ds=sidebyside

bound check utf8 characters

since we load the fontmap from psf1 font files, we only have characters
for a maximum codepoint of 0xFFFF, so we save the char in an
unsigned short (16bit) but we decode up to 6 bytes of utf8
so we have to correctly bound check the assignment, else we can get
garbled characters on the terminal

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
---

diff --git a/vncterm.c b/vncterm.c
index baaa379..3ca00ba 100644
--- a/vncterm.c
+++ b/vncterm.c
@@ -1790,7 +1790,11 @@ vncterm_puts (vncTerm *vt, const char *buf, int len)
 	    vt->utf_char = (vt->utf_char << 6) | (c & 0x3f);
 	    vt->utf_count--;
 	    if (vt->utf_count == 0) {
-	      tc = vt->utf_char;
+		if (vt->utf_char <= USHRT_MAX) {
+		  tc = vt->utf_char;
+		} else {
+		  tc = 0;
+		}
 	    } else {
 	      continue;
 	    }