From cca202a5e59578247cd7f0496056884f5c9cc338 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Wed, 8 Nov 2023 15:58:13 +0100 Subject: fbdev: hyperv_fb: fix uninitialized local variable use When CONFIG_SYSFB is disabled, the hyperv_fb driver can now run into undefined behavior on a gen2 VM, as indicated by this smatch warning: drivers/video/fbdev/hyperv_fb.c:1077 hvfb_getmem() error: uninitialized symbol 'base'. drivers/video/fbdev/hyperv_fb.c:1077 hvfb_getmem() error: uninitialized symbol 'size'. Since there is no way to know the actual framebuffer in this configuration, just return an allocation failure here, which should avoid the build warning and the undefined behavior. Reported-by: kernel test robot Reported-by: Dan Carpenter Closes: https://lore.kernel.org/r/202311070802.YCpvehaz-lkp@intel.com/ Fixes: a07b50d80ab6 ("hyperv: avoid dependency on screen_info") Signed-off-by: Arnd Bergmann Signed-off-by: Helge Deller --- drivers/video/fbdev/hyperv_fb.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/video/fbdev/hyperv_fb.c b/drivers/video/fbdev/hyperv_fb.c index bf59daf862fc..a80939fe2ee6 100644 --- a/drivers/video/fbdev/hyperv_fb.c +++ b/drivers/video/fbdev/hyperv_fb.c @@ -1013,6 +1013,8 @@ static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info) } else if (IS_ENABLED(CONFIG_SYSFB)) { base = screen_info.lfb_base; size = screen_info.lfb_size; + } else { + goto err1; } /* -- cgit v1.2.3