From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: [PATCH 11/11] [RFC] drm/i915/dp: fix array overflow warning Date: Mon, 22 Mar 2021 17:02:49 +0100 Message-ID: <20210322160253.4032422-12-arnd@kernel.org> References: <20210322160253.4032422-1-arnd@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1616429143; bh=ppc9fZupOrjA6hpvzPGCige1HMZi82rKq0OzuPiwp30=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KfNQhB8I6TCilI9rWZIUvrD60VxxXK7zzzf2CzYQVcPCX4dTFC+5vrq57/HXue9eN 7bPBi+K09Uuo8FgLHJN5cLADDDnPtd+D6sEhJhO/VLvKBoLaRa1BESfKHtMpZuvnwh D3Vc4uZU9Dcg74j9eeiZa4qkcbeOz2ZvcezhMcicUmJ4FzCGExiFKR4ER32CvaOaWV akMTcdJNfGrFGH5JvGZ7qns0oNxpRTzGH0qZ76EqyoQfhjLJvxqyHurET1PBvf6svb dBMESSwDo3iJsmPDGBQ1mVtfw03/ahNqDciEznfWOfvZZJNzU8YYxi4I1doMFPdTRo oo8eGNoKcMUqQ== In-Reply-To: <20210322160253.4032422-1-arnd-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> List-ID: Content-Type: text/plain; charset="utf-8" To: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Martin Sebor , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , David Airlie , Daniel Vetter Cc: Arnd Bergmann , x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, Ning Sun , Kalle Valo , Simon Kelley , James Smart , "James E.J. Bottomley" , Anders Larsen , Tejun Heo , Serge Hallyn , Imre Deak , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, tboot-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, intel-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, ath11k-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-wireless-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-scsi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= , Manasi From: Arnd Bergmann gcc-11 warns that intel_dp_check_mst_status() has a local array of fourteen bytes and passes the last four bytes into a function that expects a six-byte array: drivers/gpu/drm/i915/display/intel_dp.c: In function ‘intel_dp_check_mst_status’: drivers/gpu/drm/i915/display/intel_dp.c:4556:22: error: ‘drm_dp_channel_eq_ok’ reading 6 bytes from a region of size 4 [-Werror=stringop-overread] 4556 | !drm_dp_channel_eq_ok(&esi[10], intel_dp->lane_count)) { | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/i915/display/intel_dp.c:4556:22: note: referencing argument 1 of type ‘const u8 *’ {aka ‘const unsigned char *’} In file included from drivers/gpu/drm/i915/display/intel_dp.c:38: include/drm/drm_dp_helper.h:1459:6: note: in a call to function ‘drm_dp_channel_eq_ok’ 1459 | bool drm_dp_channel_eq_ok(const u8 link_status[DP_LINK_STATUS_SIZE], | ^~~~~~~~~~~~~~~~~~~~ Clearly something is wrong here, but I can't quite figure out what. Changing the array size to 16 bytes avoids the warning, but is probably the wrong solution here. Signed-off-by: Arnd Bergmann --- drivers/gpu/drm/i915/display/intel_dp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 8c12d5375607..830e2515f119 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -65,7 +65,7 @@ #include "intel_vdsc.h" #include "intel_vrr.h" -#define DP_DPRX_ESI_LEN 14 +#define DP_DPRX_ESI_LEN 16 /* DP DSC throughput values used for slice count calculations KPixels/s */ #define DP_DSC_PEAK_PIXEL_RATE 2720000 -- 2.29.2