Hi, On Wed, Mar 20, 2024 at 12:56 AM Helge Deller <deller@xxxxxx> wrote: > > On 3/19/24 00:46, Justin Stitt wrote: > > strncpy() is deprecated for use on NUL-terminated destination strings > > [1] and as such we should prefer more robust and less ambiguous string > > interfaces. > > > > Let's use the new 2-argument strscpy() which guarantees NUL-termination > > on the destination buffer while also simplifying the syntax. Note that > > strscpy() will not NUL-pad the destination buffer like strncpy() does. > > > > However, the NUL-padding behavior of strncpy() is not required since > > fbdev is already NUL-allocated from au1200fb_drv_probe() -> > > frameuffer_alloc(), rendering any additional NUL-padding redundant. > > | p = kzalloc(fb_info_size + size, GFP_KERNEL); > > > > Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] > > Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2] > > Link: https://github.com/KSPP/linux/issues/90 > > Cc: linux-hardening@xxxxxxxxxxxxxxx > > Signed-off-by: Justin Stitt <justinstitt@xxxxxxxxxx> > > --- > > Note: build-tested only. > > > > Found with: $ rg "strncpy\(" > > --- > > drivers/video/fbdev/au1200fb.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/video/fbdev/au1200fb.c b/drivers/video/fbdev/au1200fb.c > > index 6f20efc663d7..e718fea63662 100644 > > --- a/drivers/video/fbdev/au1200fb.c > > +++ b/drivers/video/fbdev/au1200fb.c > > @@ -1557,7 +1557,7 @@ static int au1200fb_init_fbinfo(struct au1200fb_device *fbdev) > > return ret; > > } > > > > - strncpy(fbi->fix.id, "AU1200", sizeof(fbi->fix.id)); > > + strscpy(fbi->fix.id, "AU1200"); > > I wonder if you really build-tested this, as this driver is for the mips architecture... > And I don't see a strscpy() function which takes just 2 arguments. > But I might be wrong.... I did build successfully :thumbs_up: Commit e6584c3964f2f ("string: Allow 2-argument strscpy()") introduced this new strscpy() form; it is present in string.h on Linus' tree. > > Helge Thanks Justin
