From dcaefc82395841fa15aa70a2c8841cda4f87125f Mon Sep 17 00:00:00 2001 From: Thomas Zimmermann Date: Fri, 19 Apr 2024 10:28:58 +0200 Subject: [PATCH] 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: Thomas Zimmermann Reviewed-by: Javier Martinez Canillas Link: https://patchwork.freedesktop.org/patch/msgid/20240419083331.7761-6-tzimmermann@suse.de --- drivers/video/fbdev/core/fb_defio.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/video/fbdev/core/fb_defio.c b/drivers/video/fbdev/core/fb_defio.c index 45e8708eb223a..37910753759cd 100644 --- a/drivers/video/fbdev/core/fb_defio.c +++ b/drivers/video/fbdev/core/fb_defio.c @@ -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; -- 2.39.5