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| author | Richard Fitzgerald <rf@opensource.cirrus.com> | 2024-07-02 13:08:09 +0200 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2024-07-02 14:59:35 +0200 |
| commit | 62412a9357b16a4e39dc582deb2e2a682b92524c (patch) | |
| tree | 2108fde9c13b61c620ab13e97fbe5e208598d956 /drivers/firmware | |
| parent | ASoC: simple-audio-mux: add state-labels (diff) | |
| download | linux-62412a9357b16a4e39dc582deb2e2a682b92524c.tar.xz linux-62412a9357b16a4e39dc582deb2e2a682b92524c.zip | |
firmware: cs_dsp: Don't allow writes to read-only controls
Add a check to cs_dsp_coeff_write_ctrl() to abort if the control
is not writeable.
The cs_dsp code originated as an ASoC driver (wm_adsp) where all
controls were exported as ALSA controls. It relied on ALSA to
enforce the read-only permission. Now that the code has been
separated from ALSA/ASoC it must perform its own permission check.
This isn't currently causing any problems so there shouldn't be any
need to backport this. If the client of cs_dsp exposes the control as
an ALSA control, it should set permissions on that ALSA control to
protect it. The few uses of cs_dsp_coeff_write_ctrl() inside drivers
are for writable controls.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://patch.msgid.link/20240702110809.16836-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/firmware')
| -rw-r--r-- | drivers/firmware/cirrus/cs_dsp.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/firmware/cirrus/cs_dsp.c b/drivers/firmware/cirrus/cs_dsp.c index 0d139e4de37c..d2aa0980ed78 100644 --- a/drivers/firmware/cirrus/cs_dsp.c +++ b/drivers/firmware/cirrus/cs_dsp.c @@ -796,6 +796,9 @@ int cs_dsp_coeff_write_ctrl(struct cs_dsp_coeff_ctl *ctl, lockdep_assert_held(&ctl->dsp->pwr_lock); + if (ctl->flags && !(ctl->flags & WMFW_CTL_FLAG_WRITEABLE)) + return -EPERM; + if (len + off * sizeof(u32) > ctl->len) return -EINVAL; |