commit 18e845f7dfe089bc0c6a89c10c496054d30a681e
author Li Qiang <liq3ea@163.com> Mon Mar 18 09:04:42 2019 +0800
committer Gerd Hoffmann <kraxel@redhat.com> Mon Mar 18 10:49:18 2019 +0100
tree b606bc942a6587cb7afdcc870f8f0c06b215122e
parent d4e65539e570d5872003710b5a1064489911d33d

vnc: fix unalignment access in tight_pack24

When adding '-fsanitize=undefined' in compiling configuration
and connect VM with vnc, it reports following error:

ui/vnc-enc-tight.c:910:13: runtime error: load of
misaligned address 0x621000466513 for type 'uint32_t',
which requires 4 byte alignment

This patch fix this issue.

Signed-off-by: Li Qiang <liq3ea@163.com>
Message-id: 20190318010442.14897-1-liq3ea@163.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

ui/vnc-enc-tight.c

diff --git a/ui/vnc-enc-tight.c b/ui/vnc-enc-tight.c
index 0b4a5ac7..d20cd1d 100644
--- a/ui/vnc-enc-tight.c
+++ b/ui/vnc-enc-tight.c
@@ -886,11 +886,11 @@
  */
 static void tight_pack24(VncState *vs, uint8_t *buf, size_t count, size_t *ret)
 {
-    uint32_t *buf32;
+    uint8_t *buf8;
     uint32_t pix;
     int rshift, gshift, bshift;
 
-    buf32 = (uint32_t *)buf;
+    buf8 = buf;
 
     if (1 /* FIXME */) {
         rshift = vs->client_pf.rshift;
@@ -907,10 +907,11 @@
     }
 
     while (count--) {
-        pix = *buf32++;
+        pix = ldl_he_p(buf8);
         *buf++ = (char)(pix >> rshift);
         *buf++ = (char)(pix >> gshift);
         *buf++ = (char)(pix >> bshift);
+        buf8 += 4;
     }
 }