diff options
| author | Hans Verkuil <hverkuil-cisco@xs4all.nl> | 2020-11-27 12:36:32 +0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab+huawei@kernel.org> | 2020-12-01 18:19:07 +0300 |
| commit | 024e01dead12c2b9fbe31216f2099401ebb78a4a (patch) | |
| tree | 2afa4345582131326516ea095ead4322fcad08fb | |
| parent | d904eb0b351fe5545d9ba5b85844342f49025923 (diff) | |
| download | linux-024e01dead12c2b9fbe31216f2099401ebb78a4a.tar.xz | |
media: pulse8-cec: fix duplicate free at disconnect or probe error
Commit 601282d65b96 ("media: pulse8-cec: use adap_free callback") used
the adap_free callback to clean up on disconnect. What I forgot was that
in the probe it will call cec_delete_adapter() followed by kfree(pulse8)
if an error occurs. But by using the adap_free callback,
cec_delete_adapter() is already freeing the pulse8 struct.
This wasn't noticed since normally the probe works fine, but Pulse-Eight
published a new firmware version that caused a probe error, so now it
hits this bug. This affects firmware version 12, but probably any
version >= 10.
Commit aa9eda76129c ("media: pulse8-cec: close serio in disconnect, not
adap_free") made this worse by adding the line 'pulse8->serio = NULL'
right after the call to cec_unregister_adapter in the disconnect()
function. Unfortunately, cec_unregister_adapter will typically call
cec_delete_adapter (unless a filehandle to the cec device is still
open), which frees the pulse8 struct. So now it will also crash on a
simple unplug of the Pulse-Eight device.
With this fix both the unplug issue and a probe() error situation are
handled correctly again.
It will still fail to probe() with a v12 firmware, that's something
to look at separately.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reported-by: Maxime Ripard <mripard@kernel.org>
Tested-by: Maxime Ripard <mripard@kernel.org>
Fixes: aa9eda76129c ("media: pulse8-cec: close serio in disconnect, not adap_free")
Fixes: 601282d65b96 ("media: pulse8-cec: use adap_free callback")
Cc: <stable@vger.kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
| -rw-r--r-- | drivers/media/cec/usb/pulse8/pulse8-cec.c | 9 |
1 files changed, 4 insertions, 5 deletions
diff --git a/drivers/media/cec/usb/pulse8/pulse8-cec.c b/drivers/media/cec/usb/pulse8/pulse8-cec.c index e4d8446b87da..5d3a3f775bc8 100644 --- a/drivers/media/cec/usb/pulse8/pulse8-cec.c +++ b/drivers/media/cec/usb/pulse8/pulse8-cec.c @@ -650,7 +650,6 @@ static void pulse8_disconnect(struct serio *serio) struct pulse8 *pulse8 = serio_get_drvdata(serio); cec_unregister_adapter(pulse8->adap); - pulse8->serio = NULL; serio_set_drvdata(serio, NULL); serio_close(serio); } @@ -830,8 +829,10 @@ static int pulse8_connect(struct serio *serio, struct serio_driver *drv) pulse8->adap = cec_allocate_adapter(&pulse8_cec_adap_ops, pulse8, dev_name(&serio->dev), caps, 1); err = PTR_ERR_OR_ZERO(pulse8->adap); - if (err < 0) - goto free_device; + if (err < 0) { + kfree(pulse8); + return err; + } pulse8->dev = &serio->dev; serio_set_drvdata(serio, pulse8); @@ -874,8 +875,6 @@ close_serio: serio_close(serio); delete_adap: cec_delete_adapter(pulse8->adap); -free_device: - kfree(pulse8); return err; } |