[PATCH] ASoC: sh: rz-ssi: Improve error handling in rz_ssi_dma_request function
The rz_ssi_dma_request function only checks the NULL condition for the value returned by the dma_request_chan function, but this function can also return an error. If it happens, the subsequent function call to rz_ssi_dma_slave_config can lead to a kernel crash.
This patch fixes the issue by checking both error and NULL condition returned by dma_request_chan.
Signed-off-by: Biju Das biju.das.jz@bp.renesas.com --- sound/soc/sh/rz-ssi.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/sound/soc/sh/rz-ssi.c b/sound/soc/sh/rz-ssi.c index ea8d33ede5d2..3867e2efd3e0 100644 --- a/sound/soc/sh/rz-ssi.c +++ b/sound/soc/sh/rz-ssi.c @@ -676,11 +676,19 @@ static void rz_ssi_release_dma_channels(struct rz_ssi_priv *ssi) static int rz_ssi_dma_request(struct rz_ssi_priv *ssi, struct device *dev) { ssi->playback.dma_ch = dma_request_chan(dev, "tx"); + if (IS_ERR_OR_NULL(ssi->playback.dma_ch)) + ssi->playback.dma_ch = NULL; + ssi->capture.dma_ch = dma_request_chan(dev, "rx"); + if (IS_ERR_OR_NULL(ssi->capture.dma_ch)) + ssi->capture.dma_ch = NULL; + if (!ssi->playback.dma_ch && !ssi->capture.dma_ch) { ssi->playback.dma_ch = dma_request_chan(dev, "rt"); - if (!ssi->playback.dma_ch) + if (IS_ERR_OR_NULL(ssi->playback.dma_ch)) { + ssi->playback.dma_ch = NULL; goto no_dma; + }
ssi->dma_rt = true; }
Hi All,
I have send v2. So please drop this patch.
Cheers, Biju
-----Original Message----- From: Biju Das biju.das.jz@bp.renesas.com Sent: 14 August 2021 14:41 To: Jaroslav Kysela perex@perex.cz; Takashi Iwai tiwai@suse.com Cc: Biju Das biju.das.jz@bp.renesas.com; Liam Girdwood lgirdwood@gmail.com; Mark Brown broonie@kernel.org; Prabhakar Mahadev Lad prabhakar.mahadev-lad.rj@bp.renesas.com; alsa-devel@alsa- project.org; Geert Uytterhoeven geert+renesas@glider.be; Chris Paterson Chris.Paterson2@renesas.com; Biju Das biju.das@bp.renesas.com; linux- renesas-soc@vger.kernel.org Subject: [PATCH] ASoC: sh: rz-ssi: Improve error handling in rz_ssi_dma_request function
The rz_ssi_dma_request function only checks the NULL condition for the value returned by the dma_request_chan function, but this function can also return an error. If it happens, the subsequent function call to rz_ssi_dma_slave_config can lead to a kernel crash.
This patch fixes the issue by checking both error and NULL condition returned by dma_request_chan.
Signed-off-by: Biju Das biju.das.jz@bp.renesas.com
sound/soc/sh/rz-ssi.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/sound/soc/sh/rz-ssi.c b/sound/soc/sh/rz-ssi.c index ea8d33ede5d2..3867e2efd3e0 100644 --- a/sound/soc/sh/rz-ssi.c +++ b/sound/soc/sh/rz-ssi.c @@ -676,11 +676,19 @@ static void rz_ssi_release_dma_channels(struct rz_ssi_priv *ssi) static int rz_ssi_dma_request(struct rz_ssi_priv *ssi, struct device *dev) { ssi->playback.dma_ch = dma_request_chan(dev, "tx");
- if (IS_ERR_OR_NULL(ssi->playback.dma_ch))
ssi->playback.dma_ch = NULL;- ssi->capture.dma_ch = dma_request_chan(dev, "rx");
- if (IS_ERR_OR_NULL(ssi->capture.dma_ch))
ssi->capture.dma_ch = NULL;- if (!ssi->playback.dma_ch && !ssi->capture.dma_ch) { ssi->playback.dma_ch = dma_request_chan(dev, "rt");
if (!ssi->playback.dma_ch)
if (IS_ERR_OR_NULL(ssi->playback.dma_ch)) {ssi->playback.dma_ch = NULL; goto no_dma;}ssi->dma_rt = true; }
-- 2.17.1
participants (1)
-
Biju Das