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From:   "Krzysztof Halasa" <khalasa@piap.pl>
To:     Philipp Zabel <p.zabel@pengutronix.de>
Cc:     Mauro Carvalho Chehab <mchehab@kernel.org>,
        linux-media@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] MEDIA CODA: Fix NULL ptr dereference in the encoder.
Sender: khalasa@piap.pl
Date:   Tue, 16 Mar 2021 09:23:47 +0100
Message-ID: <m3a6r3tsks.fsf@t19.piap.pl>
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Precedence: bulk

ctx->mb_err_cnt_ctrl could be NULL in case of failed initialization
(on decoders), and encoders don't use it at all.

Fixes: b2d3bef1aa78 ("media: coda: Add a V4L2 user for control error macrob=
locks count")
Signed-off-by: Krzysztof Halasa <khalasa@piap.pl>
Cc: stable@vger.kernel.org # 5.11+

diff --git a/drivers/media/platform/coda/coda-bit.c b/drivers/media/platfor=
m/coda/coda-bit.c
index 2f42808c43a4..26e37cbfe8dd 100644
--- a/drivers/media/platform/coda/coda-bit.c
+++ b/drivers/media/platform/coda/coda-bit.c
@@ -2373,8 +2373,10 @@ static void coda_finish_decode(struct coda_ctx *ctx)
 	if (err_mb > 0) {
 		if (__ratelimit(&dev->mb_err_rs))
 			coda_dbg(1, ctx, "errors in %d macroblocks\n", err_mb);
-		v4l2_ctrl_s_ctrl(ctx->mb_err_cnt_ctrl,
-				 v4l2_ctrl_g_ctrl(ctx->mb_err_cnt_ctrl) + err_mb);
+		if (ctx->mb_err_cnt_ctrl)
+			v4l2_ctrl_s_ctrl(ctx->mb_err_cnt_ctrl,
+					 v4l2_ctrl_g_ctrl(ctx->mb_err_cnt_ctrl)
+					 + err_mb);
 	}
=20
 	if (dev->devtype->product =3D=3D CODA_HX4 ||
diff --git a/drivers/media/platform/coda/coda-common.c b/drivers/media/plat=
form/coda/coda-common.c
index 96802b8f47ea..285c80f87b65 100644
--- a/drivers/media/platform/coda/coda-common.c
+++ b/drivers/media/platform/coda/coda-common.c
@@ -2062,7 +2062,8 @@ static int coda_start_streaming(struct vb2_queue *q, =
unsigned int count)
 	if (q_data_dst->fourcc =3D=3D V4L2_PIX_FMT_JPEG)
 		ctx->params.gop_size =3D 1;
 	ctx->gopcounter =3D ctx->params.gop_size - 1;
-	v4l2_ctrl_s_ctrl(ctx->mb_err_cnt_ctrl, 0);
+	if (ctx->mb_err_cnt_ctrl)
+		v4l2_ctrl_s_ctrl(ctx->mb_err_cnt_ctrl, 0);
=20
 	ret =3D ctx->ops->start_streaming(ctx);
 	if (ctx->inst_type =3D=3D CODA_INST_DECODER) {

--=20
Krzysztof Ha=C5=82asa

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