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From: Dan Carpenter <dan.carpenter@oracle.com>
To: Jani Nikula <jani.nikula@linux.intel.com>,
	Daniel Vetter <daniel@ffwll.ch>
Cc: "Joonas Lahtinen" <joonas.lahtinen@linux.intel.com>,
	"Rodrigo Vivi" <rodrigo.vivi@intel.com>,
	"Tvrtko Ursulin" <tvrtko.ursulin@linux.intel.com>,
	"David Airlie" <airlied@linux.ie>,
	"Ville Syrjälä" <ville.syrjala@linux.intel.com>,
	"Chris Wilson" <chris@chris-wilson.co.uk>,
	"Sean Paul" <seanpaul@chromium.org>,
	"Fernando Ramos" <greenfoo@u92.eu>,
	"Maarten Lankhorst" <maarten.lankhorst@linux.intel.com>,
	"Matt Roper" <matthew.d.roper@intel.com>,
	"Eric Anholt" <eric@anholt.net>,
	intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org,
	kernel-janitors@vger.kernel.org
Subject: [PATCH] drm/i915/overlay: Prevent divide by zero bugs in scaling
Date: Mon, 24 Jan 2022 15:24:09 +0300	[thread overview]
Message-ID: <20220124122409.GA31673@kili> (raw)

Smatch detected a divide by zero bug in check_overlay_scaling().

    drivers/gpu/drm/i915/display/intel_overlay.c:976 check_overlay_scaling()
    error: potential divide by zero bug '/ rec->dst_height'.
    drivers/gpu/drm/i915/display/intel_overlay.c:980 check_overlay_scaling()
    error: potential divide by zero bug '/ rec->dst_width'.

Prevent this by ensuring that the dst height and width are non-zero.

Fixes: 02e792fbaadb ("drm/i915: implement drmmode overlay support v4")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
From static analysis.  Not tested.

 drivers/gpu/drm/i915/display/intel_overlay.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_overlay.c b/drivers/gpu/drm/i915/display/intel_overlay.c
index 1a376e9a1ff3..d610e48cab94 100644
--- a/drivers/gpu/drm/i915/display/intel_overlay.c
+++ b/drivers/gpu/drm/i915/display/intel_overlay.c
@@ -959,6 +959,9 @@ static int check_overlay_dst(struct intel_overlay *overlay,
 	const struct intel_crtc_state *pipe_config =
 		overlay->crtc->config;
 
+	if (rec->dst_height == 0 || rec->dst_width == 0)
+		return -EINVAL;
+
 	if (rec->dst_x < pipe_config->pipe_src_w &&
 	    rec->dst_x + rec->dst_width <= pipe_config->pipe_src_w &&
 	    rec->dst_y < pipe_config->pipe_src_h &&
-- 
2.20.1


             reply	other threads:[~2022-01-24 12:26 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-01-24 12:24 Dan Carpenter [this message]
2022-01-25  5:17 ` [PATCH] drm/i915/overlay: Prevent divide by zero bugs in scaling Ville Syrjälä

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