[pve-devel] [PATCH vncterm 2/3] bound check utf8 characters

[Dominik Csapak]

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 at proxmox.com>
---
 vncterm.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/vncterm.c b/vncterm.c
index baaa379..cc61293 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;
 	    }
-- 
2.1.4