From 5c80c4fced22ae719d37db754144e75688eb52c8 Mon Sep 17 00:00:00 2001 From: Justin Stitt Date: Fri, 22 Sep 2023 11:58:06 +0000 Subject: isdn: replace deprecated strncpy with strscpy `strncpy` is deprecated for use on NUL-terminated destination strings [1] and as such we should prefer more robust and less ambiguous string interfaces. We expect `iclock->name` to be NUL-terminated based on its use within printk: | printk(KERN_DEBUG "%s: %s %d\n", __func__, iclock->name, | iclock->pri); `iclock` is zero-initialized and as such is already NUL-padded which means strncpy is doing extra work here by eagerly NUL-padding the destination buffer. Considering the above, a suitable replacement is `strscpy` [2] due to the fact that it guarantees NUL-termination on the destination buffer without unnecessarily NUL-padding. 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@vger.kernel.org Signed-off-by: Justin Stitt Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20230922-strncpy-drivers-isdn-misdn-clock-c-v1-1-3ba2a5ae627a@google.com Signed-off-by: Kees Cook --- drivers/isdn/mISDN/clock.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/isdn') diff --git a/drivers/isdn/mISDN/clock.c b/drivers/isdn/mISDN/clock.c index 01d878168ef2..f71eb61db131 100644 --- a/drivers/isdn/mISDN/clock.c +++ b/drivers/isdn/mISDN/clock.c @@ -96,7 +96,7 @@ struct mISDNclock printk(KERN_ERR "%s: No memory for clock entry.\n", __func__); return NULL; } - strncpy(iclock->name, name, sizeof(iclock->name) - 1); + strscpy(iclock->name, name, sizeof(iclock->name)); iclock->pri = pri; iclock->priv = priv; iclock->ctl = ctl; -- cgit v1.2.3