Commit dcaefc82 authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

fbdev/deferred-io: Test smem_start for I/O memory 



Test smem_start before looking up pages from its value. Return
NULL if it is unset. This will result in a SIGBUS signal.

Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: default avatarJavier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240419083331.7761-6-tzimmermann@suse.de
parent abc79a0e

drivers/video/fbdev/core/fb_defio.c

+2 −2
Original line number Diff line number Diff line
@@ -26,11 +26,11 @@ 
static struct page *fb_deferred_io_page(struct fb_info *info, unsigned long offs)

{

	const void *screen_buffer = info->screen_buffer;

	struct page *page;

	struct page *page = NULL;



	if (is_vmalloc_addr(screen_buffer + offs))

		page = vmalloc_to_page(screen_buffer + offs);

	else

	else if (info->fix.smem_start)

		page = pfn_to_page((info->fix.smem_start + offs) >> PAGE_SHIFT);



	return page;