On Sat, Apr 25, 2020 at 3:30 PM Shengjiu Wang <shengjiu.wang@xxxxxxx> wrote:
>
> The patch 955ac624058f: "ASoC: fsl_easrc: Add EASRC ASoC CPU DAI
> drivers" from Apr 16, 2020, leads to the following Smatch complaint:
>
> sound/soc/fsl/fsl_easrc.c:1529 fsl_easrc_hw_free()
> warn: variable dereferenced before check 'ctx' (see line 1527)
>
> sound/soc/fsl/fsl_easrc.c
> 1526 struct fsl_asrc_pair *ctx = runtime->private_data;
> 1527 struct fsl_easrc_ctx_priv *ctx_priv = ctx->private;
> ^^^^^
> Dereference
>
> 1528
> 1529 if (ctx && (ctx_priv->ctx_streams & BIT(substream->stream))) {
> ^^^
> This check is too late, to prevent a NULL dereference.
>
> 1530 ctx_priv->ctx_streams &= ~BIT(substream->stream);
> 1531 fsl_easrc_release_context(ctx);
>
> Fixes: 955ac624058f ("ASoC: fsl_easrc: Add EASRC ASoC CPU DAI drivers")
> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx>
> ---
Sorry，I forgot the changes:
changes in v2:
- refine the commit subject.
best regards
Wang shengjiu
> sound/soc/fsl/fsl_easrc.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/sound/soc/fsl/fsl_easrc.c b/sound/soc/fsl/fsl_easrc.c
> index 97658e1f4989..20326bffab64 100644
> --- a/sound/soc/fsl/fsl_easrc.c
> +++ b/sound/soc/fsl/fsl_easrc.c
> @@ -1524,9 +1524,14 @@ static int fsl_easrc_hw_free(struct snd_pcm_substream *substream,
> {
> struct snd_pcm_runtime *runtime = substream->runtime;
> struct fsl_asrc_pair *ctx = runtime->private_data;
> - struct fsl_easrc_ctx_priv *ctx_priv = ctx->private;
> + struct fsl_easrc_ctx_priv *ctx_priv;
>
> - if (ctx && (ctx_priv->ctx_streams & BIT(substream->stream))) {
> + if (!ctx)
> + return -EINVAL;
> +
> + ctx_priv = ctx->private;
> +
> + if (ctx_priv->ctx_streams & BIT(substream->stream)) {
> ctx_priv->ctx_streams &= ~BIT(substream->stream);
> fsl_easrc_release_context(ctx);
> }
> --
> 2.21.0
>
