[PATCH] tdfxfb: Fix buffer overrun

The pseudo_palette has room only for 16 entries, but tdfxfb_setcolreg may
attempt to write more.

Coverity Bug 557

Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 23 insertions, 19 deletions

diff --git a/drivers/video/tdfxfb.c b/drivers/video/tdfxfb.c
index 3e7baf4c9fa8..5e5328d682db 100644
--- a/drivers/video/tdfxfb.c
+++ b/drivers/video/tdfxfb.c
@@ -786,28 +786,32 @@ static int tdfxfb_setcolreg(unsigned regno, unsigned red, unsigned green,
         if (regno >= info->cmap.len || regno > 255) return 1;
    
         switch (info->fix.visual) {
-                case FB_VISUAL_PSEUDOCOLOR:
-                        rgbcol =(((u32)red   & 0xff00) << 8) |
-                                (((u32)green & 0xff00) << 0) |
-                                (((u32)blue  & 0xff00) >> 8);
-                        do_setpalentry(par, regno, rgbcol);
-                        break;
-                /* Truecolor has no hardware color palettes. */
-                case FB_VISUAL_TRUECOLOR:
+        case FB_VISUAL_PSEUDOCOLOR:
+                rgbcol =(((u32)red   & 0xff00) << 8) |
+                        (((u32)green & 0xff00) << 0) |
+                        (((u32)blue  & 0xff00) >> 8);
+                do_setpalentry(par, regno, rgbcol);
+                break;
+        /* Truecolor has no hardware color palettes. */
+        case FB_VISUAL_TRUECOLOR:
+                if (regno < 16) {
                         rgbcol = (CNVT_TOHW( red, info->var.red.length) <<
                                   info->var.red.offset) |
-                                 (CNVT_TOHW( green, info->var.green.length) <<
-                                  info->var.green.offset) |
-                                 (CNVT_TOHW( blue, info->var.blue.length) <<
-                                  info->var.blue.offset) |
-                                 (CNVT_TOHW( transp, info->var.transp.length) <<
-                                  info->var.transp.offset);
-                                par->palette[regno] = rgbcol;
-                        break;
-                default:
-                        DPRINTK("bad depth %u\n", info->var.bits_per_pixel);
-                        break;
+                                (CNVT_TOHW( green, info->var.green.length) <<
+                                 info->var.green.offset) |
+                                (CNVT_TOHW( blue, info->var.blue.length) <<
+                                 info->var.blue.offset) |
+                                (CNVT_TOHW( transp, info->var.transp.length) <<
+                                 info->var.transp.offset);
+                        par->palette[regno] = rgbcol;
+                }
+
+                break;
+        default:
+                DPRINTK("bad depth %u\n", info->var.bits_per_pixel);
+                break;
         }
+
         return 0;
 }