From c6595bf672e42bb6e4a11b6f39b58baa14a41c4f Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 26 Mar 2012 21:15:53 +0100 Subject: [PATCH] drm: Validate requested virtual size against allocated fb size commit 62fb376e214d3c1bfdf6fbb77dac162f6da04d7e upstream. mplayer -vo fbdev tries to create a screen that is twice as tall as the allocated framebuffer for "doublebuffering". By default, and all in-tree users, only sufficient memory is allocated and mapped to satisfy the smallest framebuffer and the virtual size is no larger than the actual. For these users, we should therefore reject any userspace request to create a screen that requires a buffer larger than the framebuffer originally allocated. References: https://bugs.freedesktop.org/show_bug.cgi?id=38138 Signed-off-by: Chris Wilson Reviewed-by: Daniel Vetter Signed-off-by: Dave Airlie Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/drm_fb_helper.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index aada26f63decc..7432e724ecbb9 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -617,9 +617,13 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var, return -EINVAL; /* Need to resize the fb object !!! */ - if (var->bits_per_pixel > fb->bits_per_pixel || var->xres > fb->width || var->yres > fb->height) { + if (var->bits_per_pixel > fb->bits_per_pixel || + var->xres > fb->width || var->yres > fb->height || + var->xres_virtual > fb->width || var->yres_virtual > fb->height) { DRM_DEBUG("fb userspace requested width/height/bpp is greater than current fb " - "object %dx%d-%d > %dx%d-%d\n", var->xres, var->yres, var->bits_per_pixel, + "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n", + var->xres, var->yres, var->bits_per_pixel, + var->xres_virtual, var->yres_virtual, fb->width, fb->height, fb->bits_per_pixel); return -EINVAL; } -- 2.47.2