Bug#166746: xlibmesa3: Several bugs causing segfaults with Warcraft III in wine

[Michael Karcher]

Package: xlibmesa3
Version: 4.2.1-2
Severity: normal
Tags: patch

There are some minor bugs that cause the mesa library to access bad memory
when using special parameters. This fixes issues for
 - Converting a 1x2 texture to a 16 bit per pixel format
 - Uninitialized variables in some code path
 - Access (this time read only) behind texture data for linear interpolation
   when auto-generating mip-maps.
All these three bugs appear when running Warcraft III in wine.

(This patch is ready for inclusion in debian/patchs in the X sources)

diff -urN xc/extras/Mesa/src/cva.c xc/extras/Mesa/src/cva.c
--- xc/extras/Mesa/src/cva.c    Fri May 18 18:59:53 2001
+++ xc/extras/Mesa/src/cva.c    Fri Aug 23 19:53:30 2002
@@ -546,9 +546,6 @@
            elt->stride = sizeof(GLuint);
            elt->flags = 0;
         } else {
-           elt->data = cva->store.Elt;
-           elt->stride = sizeof(GLuint);
-
            if (cva->elt_count > cva->elt_size) 
            {
               while (cva->elt_count > (cva->elt_size *= 2)) {};
@@ -556,6 +553,9 @@
               cva->store.Elt = (GLuint *) MALLOC(cva->elt_size * 
                                                  sizeof(GLuint));
            }
+           elt->data = cva->store.Elt;
+           elt->stride = sizeof(GLuint);
+
            cva->EltFunc( elt->data, &cva->Elt, 0, cva->elt_count );
         }      
         elt->start = VEC_ELT(elt, GLuint, 0); 
@@ -812,8 +812,8 @@
         VB->FlagMax = n;
       }
 
-      VB->Flag[n] |= VERT_END_VB;
    }
+    VB->Flag[n] |= VERT_END_VB;
 }
 
 void gl_cva_force_precalc( GLcontext *ctx )
diff -urN xc/extras/Mesa/src/texutil.c xc/extras/Mesa/src/texutil.c
--- xc/extras/Mesa/src/texutil.c        Sat May 19 02:03:18 2001
+++ xc/extras/Mesa/src/texutil.c        Fri Aug 23 23:16:50 2002
@@ -1092,7 +1092,7 @@
    if ( convert_needs_packing( packing, format, type ) )
       convert.index |= CONVERT_PACKING_BIT;
 
-   if ( width != imageWidth )
+   if ( width != imageWidth || width & 3)
       convert.index |= CONVERT_STRIDE_BIT;
 
    return gl_convert_texsubimage2d_tab[mesaFormat]( &convert );
diff -urN xc/extras/ogl-sample/main/gfx/lib/glu/libutil/mipmap.c 
xc/extras/ogl-sample/main/gfx/lib/glu/libutil/mipmap.c
--- xc/extras/ogl-sample/main/gfx/lib/glu/libutil/mipmap.c      Thu Feb  1 
09:44:54 2001
+++ xc/extras/ogl-sample/main/gfx/lib/glu/libutil/mipmap.c      Fri Aug 23 
23:45:38 2002
@@ -1470,9 +1470,11 @@
                 }
                 temp += group_size;
                percent = y_percent * highx_float;
-                for (k = 0, temp_index = temp; k < components; 
-                    k++, temp_index += element_size) {
-                        totals[k] += (GLubyte)(*(temp_index)) * percent;
+               if(highx_float != 0) {  /* Skip after-last pixel */
+                    for (k = 0, temp_index = temp; k < components; 
+                        k++, temp_index += element_size) {
+                            totals[k] += (GLubyte)(*(temp_index)) * percent;
+                    }
                 }
 
 
@@ -1524,9 +1526,11 @@
                }
                temp += group_size;
                percent = y_percent * highx_float;
-                for (k = 0, temp_index = temp; k < components; 
-                    k++, temp_index += element_size) {
-                        totals[k] += (GLubyte)(*(temp_index)) * percent;
+               if(highx_float != 0) {
+                    for (k = 0, temp_index = temp; k < components; 
+                        k++, temp_index += element_size) {
+                            totals[k] += (GLubyte)(*(temp_index)) * percent;
+                    }
                }
            } else {
                percent = (highy_float-lowy_float)*(highx_float-lowx_float);


-- System Information
Debian Release: 3.0
Architecture: i386
Kernel: Linux achilles.karcher.de 2.4.18 #1 Don Aug 15 23:15:36 CEST 2002 i686
Locale: LANG=de_DE.ISO-8859-1, LC_CTYPE=de_DE.ISO-8859-1

Versions of packages xlibmesa3 depends on:
ii  debconf                   1.0.32         Debian configuration management sy
ii  libc6                     2.2.5-14.3.0.1 GNU C Library: Shared libraries an
ii  libstdc++2.10-glibc2.2    1:2.95.4-7     The GNU stdc++ library
ii  xlibs                     4.2.1-2        X Window System client libraries