From 5317797e9cd07ff48132a36d545c25c1687ee676 Mon Sep 17 00:00:00 2001 From: Justin Stitt Date: Wed, 20 Mar 2024 23:22:02 +0000 Subject: [PATCH] video: hdmi: prefer length specifier in format over string copying strncpy() is deprecated for use on NUL-terminated destination strings [1] and as such we should prefer more robust and less ambiguous string interfaces. It looks like the main use of strncpy() here is to limit the amount of bytes printed from hdmi_log() by using a tmp buffer and limiting the number of bytes copied. Really, we should use the %.s format qualifier to achieve this. 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 Link: https://github.com/KSPP/linux/issues/90 Cc: linux-hardening@vger.kernel.org Signed-off-by: Justin Stitt Reviewed-by: Kees Cook Signed-off-by: Helge Deller --- drivers/video/hdmi.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) diff --git a/drivers/video/hdmi.c b/drivers/video/hdmi.c index 03c7f27dde495..ba301f3f4951e 100644 --- a/drivers/video/hdmi.c +++ b/drivers/video/hdmi.c @@ -1310,17 +1310,11 @@ static void hdmi_spd_infoframe_log(const char *level, struct device *dev, const struct hdmi_spd_infoframe *frame) { - u8 buf[17]; - hdmi_infoframe_log_header(level, dev, (const struct hdmi_any_infoframe *)frame); - memset(buf, 0, sizeof(buf)); - - strncpy(buf, frame->vendor, 8); - hdmi_log(" vendor: %s\n", buf); - strncpy(buf, frame->product, 16); - hdmi_log(" product: %s\n", buf); + hdmi_log(" vendor: %.8s\n", frame->vendor); + hdmi_log(" product: %.16s\n", frame->product); hdmi_log(" source device information: %s (0x%x)\n", hdmi_spd_sdi_get_name(frame->sdi), frame->sdi); }