fbdev: atafb - add palette register check

Add check if palette register number is in correct range
for few drivers which miss it. The regno value comes
indirectly from user space.

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

diff --git a/drivers/video/atafb.c b/drivers/video/atafb.c
index 37624f7..b7687c5 100644 (file)
--- a/drivers/video/atafb.c
+++ b/drivers/video/atafb.c
@@ -2242,6 +2242,9 @@ static int ext_setcolreg(unsigned int regno, unsigned int red,
        if (!external_vgaiobase)
                return 1;
 
+       if (regno > 255)
+               return 1;
+
        switch (external_card_type) {
        case IS_VGA:
                OUTB(0x3c8, regno);