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| author | Berk Cem Goksel <berkcgoksel@gmail.com> | 2026-04-13 06:49:41 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-04-27 07:30:19 -0600 |
| commit | 59b622a043cffc58b7638cd85ae6c30a0904f8e6 (patch) | |
| tree | 090e2b9885659291365c411fb1b7fee11cd44613 /tools/perf/scripts/python/flamegraph.py | |
| parent | 3b0fa5530a0e3c3defd1e1f0ec813a1cc8079713 (diff) | |
ALSA: caiaq: take a reference on the USB device in create_card()
commit 80bb50e2d459213cccff3111d5ef98ed4238c0d5 upstream.
The caiaq driver stores a pointer to the parent USB device in
cdev->chip.dev but never takes a reference on it. The card's
private_free callback, snd_usb_caiaq_card_free(), can run
asynchronously via snd_card_free_when_closed() after the USB
device has already been disconnected and freed, so any access to
cdev->chip.dev in that path dereferences a freed usb_device.
On top of the refcounting issue, the current card_free implementation
calls usb_reset_device(cdev->chip.dev). A reset in a free callback
is inappropriate: the device is going away, the call takes the
device lock in a teardown context, and the reset races with the
disconnect path that the callback is already cleaning up after.
Take a reference on the USB device in create_card() with
usb_get_dev(), drop it with usb_put_dev() in the free callback,
and remove the usb_reset_device() call.
Fixes: b04dcbb7f7b1 ("ALSA: caiaq: Use snd_card_free_when_closed() at disconnection")
Cc: stable@vger.kernel.org
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Signed-off-by: Berk Cem Goksel <berkcgoksel@gmail.com>
Link: https://patch.msgid.link/20260413034941.1131465-3-berkcgoksel@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'tools/perf/scripts/python/flamegraph.py')
0 files changed, 0 insertions, 0 deletions
