* Nick Desaulniers <ndesaulniers@xxxxxxxxxx>: > On Thu, Aug 31, 2023 at 2:23 PM Helge Deller <deller@xxxxxx> wrote: > > > > * Helge Deller <deller@xxxxxx>: > > > On 8/29/23 18:45, Nick Desaulniers wrote: > > > > A recent change in clang made it better about spotting snprintf that > > > > will result in truncation. Nathan reported the following instances: > > > > > > > > drivers/video/fbdev/neofb.c:1959:3: warning: 'snprintf' will always be > > > > truncated; specified size is 16, but format string expands to at least > > > > 17 [-Wfortify-source] > > > > FYI, I've added the patch below to the fbdev for-next git tree. > > [...] > > This indeed makes the warning go away, but that's more so due to the > use of strscpy now rather than snprintf. That alone is a good change > but we still have definite truncation. See below: > [...] Nick, thanks for your review and findings! Now every string should be max. 15 chars (which fits with the trailing NUL into the char[16] array). Helge Subject: [PATCH] fbdev: neofb: Shorten Neomagic product name in info struct Avoid those compiler warnings: neofb.c:1959:3: warning: 'snprintf' will always be truncated; specified size is 16, but format string expands to at least 17 [-Wfortify-source] Signed-off-by: Helge Deller <deller@xxxxxx> Reported-by: Nathan Chancellor <nathan@xxxxxxxxxx> Reported-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Link: https://lore.kernel.org/all/CAKwvOdn0xoVWjQ6ufM_rojtKb0f1i1hW-J_xYGfKDNFdHwaeHQ@xxxxxxxxxxxxxx/ Link: https://github.com/ClangBuiltLinux/linux/issues/1923 diff --git a/drivers/video/fbdev/neofb.c b/drivers/video/fbdev/neofb.c index d2f622b4c372..b58b11015c0c 100644 --- a/drivers/video/fbdev/neofb.c +++ b/drivers/video/fbdev/neofb.c @@ -1948,49 +1948,40 @@ static struct fb_info *neo_alloc_fb_info(struct pci_dev *dev, switch (info->fix.accel) { case FB_ACCEL_NEOMAGIC_NM2070: - snprintf(info->fix.id, sizeof(info->fix.id), - "MagicGraph 128"); + strscpy(info->fix.id, "MagicGraph128", sizeof(info->fix.id)); break; case FB_ACCEL_NEOMAGIC_NM2090: - snprintf(info->fix.id, sizeof(info->fix.id), - "MagicGraph 128V"); + strscpy(info->fix.id, "MagicGraph128V", sizeof(info->fix.id)); break; case FB_ACCEL_NEOMAGIC_NM2093: - snprintf(info->fix.id, sizeof(info->fix.id), - "MagicGraph 128ZV"); + strscpy(info->fix.id, "MagicGraph128ZV", sizeof(info->fix.id)); break; case FB_ACCEL_NEOMAGIC_NM2097: - snprintf(info->fix.id, sizeof(info->fix.id), - "MagicGraph 128ZV+"); + strscpy(info->fix.id, "Mag.Graph128ZV+", sizeof(info->fix.id)); break; case FB_ACCEL_NEOMAGIC_NM2160: - snprintf(info->fix.id, sizeof(info->fix.id), - "MagicGraph 128XD"); + strscpy(info->fix.id, "MagicGraph128XD", sizeof(info->fix.id)); break; case FB_ACCEL_NEOMAGIC_NM2200: - snprintf(info->fix.id, sizeof(info->fix.id), - "MagicGraph 256AV"); + strscpy(info->fix.id, "MagicGraph256AV", sizeof(info->fix.id)); info->flags |= FBINFO_HWACCEL_IMAGEBLIT | FBINFO_HWACCEL_COPYAREA | FBINFO_HWACCEL_FILLRECT; break; case FB_ACCEL_NEOMAGIC_NM2230: - snprintf(info->fix.id, sizeof(info->fix.id), - "MagicGraph 256AV+"); + strscpy(info->fix.id, "Mag.Graph256AV+", sizeof(info->fix.id)); info->flags |= FBINFO_HWACCEL_IMAGEBLIT | FBINFO_HWACCEL_COPYAREA | FBINFO_HWACCEL_FILLRECT; break; case FB_ACCEL_NEOMAGIC_NM2360: - snprintf(info->fix.id, sizeof(info->fix.id), - "MagicGraph 256ZX"); + strscpy(info->fix.id, "MagicGraph256ZX", sizeof(info->fix.id)); info->flags |= FBINFO_HWACCEL_IMAGEBLIT | FBINFO_HWACCEL_COPYAREA | FBINFO_HWACCEL_FILLRECT; break; case FB_ACCEL_NEOMAGIC_NM2380: - snprintf(info->fix.id, sizeof(info->fix.id), - "MagicGraph 256XL+"); + strscpy(info->fix.id, "Mag.Graph256XL+", sizeof(info->fix.id)); info->flags |= FBINFO_HWACCEL_IMAGEBLIT | FBINFO_HWACCEL_COPYAREA | FBINFO_HWACCEL_FILLRECT;
