2021-03-16 09:38:24

by Krzysztof Hałasa

[permalink] [raw]
Subject: [PATCH] MEDIA CODA: Fix NULL ptr dereference in the encoder.

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 macroblocks count")
Signed-off-by: Krzysztof Halasa <[email protected]>
Cc: [email protected] # 5.11+

diff --git a/drivers/media/platform/coda/coda-bit.c b/drivers/media/platform/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);
}

if (dev->devtype->product == CODA_HX4 ||
diff --git a/drivers/media/platform/coda/coda-common.c b/drivers/media/platform/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 == V4L2_PIX_FMT_JPEG)
ctx->params.gop_size = 1;
ctx->gopcounter = 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);

ret = ctx->ops->start_streaming(ctx);
if (ctx->inst_type == CODA_INST_DECODER) {

--
Krzysztof Hałasa

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