From f3fc1ea011f09156886e8f4beb240ea814f2197a Mon Sep 17 00:00:00 2001 From: Shengjiu Wang Date: Sat, 25 Apr 2020 15:19:29 +0800 Subject: [PATCH] ASoC: fsl_easrc: Check for null pointer before dereferencing "ctx" in fsl_easrc_hw_free() 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 Signed-off-by: Shengjiu Wang Acked-by: Nicolin Chen Link: https://lore.kernel.org/r/d23c939f1c9eeb3fce34b6c34d44e2d6156f663a.1587799355.git.shengjiu.wang@nxp.com Signed-off-by: Mark Brown --- 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); }