From: Takashi Iwai tiwai@suse.de

stable inclusion from stable-v4.19.325 commit 3993edf44d3df7b6e8c753eac6ac8783473fcbab category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBEAFS CVE: CVE-2024-56531

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

--------------------------------

[ Upstream commit b04dcbb7f7b1908806b7dc22671cdbe78ff2b82c ]

The USB disconnect callback is supposed to be short and not too-long waiting. OTOH, the current code uses snd_card_free() at disconnection, but this waits for the close of all used fds, hence it can take long. It eventually blocks the upper layer USB ioctls, which may trigger a soft lockup.

An easy workaround is to replace snd_card_free() with snd_card_free_when_closed(). This variant returns immediately while the release of resources is done asynchronously by the card device release at the last close.

This patch also splits the code to the disconnect and the free phases; the former is called immediately at the USB disconnect callback while the latter is called from the card destructor.

Fixes: 523f1dce3743 ("[ALSA] Add Native Instrument usb audio device support") Signed-off-by: Takashi Iwai tiwai@suse.de Link: https://patch.msgid.link/20241113111042.15058-5-tiwai@suse.de Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yu Kuai yukuai3@huawei.com Reviewed-by: Yang Erkun yangerkun@huawei.com --- sound/usb/caiaq/audio.c | 10 ++++++++-- sound/usb/caiaq/audio.h | 1 + sound/usb/caiaq/device.c | 19 +++++++++++++++---- sound/usb/caiaq/input.c | 12 +++++++++--- sound/usb/caiaq/input.h | 1 + 5 files changed, 34 insertions(+), 9 deletions(-)

diff --git a/sound/usb/caiaq/audio.c b/sound/usb/caiaq/audio.c index c6108a3d7f8f..9c6a2295d45a 100644 --- a/sound/usb/caiaq/audio.c +++ b/sound/usb/caiaq/audio.c @@ -890,14 +890,20 @@ int snd_usb_caiaq_audio_init(struct snd_usb_caiaqdev *cdev) return 0; }

-void snd_usb_caiaq_audio_free(struct snd_usb_caiaqdev *cdev) +void snd_usb_caiaq_audio_disconnect(struct snd_usb_caiaqdev *cdev) { struct device *dev = caiaqdev_to_dev(cdev);

dev_dbg(dev, "%s(%p)\n", __func__, cdev); stream_stop(cdev); +} + +void snd_usb_caiaq_audio_free(struct snd_usb_caiaqdev *cdev) +{ + struct device *dev = caiaqdev_to_dev(cdev); + + dev_dbg(dev, "%s(%p)\n", __func__, cdev); free_urbs(cdev->data_urbs_in); free_urbs(cdev->data_urbs_out); kfree(cdev->data_cb_info); } - diff --git a/sound/usb/caiaq/audio.h b/sound/usb/caiaq/audio.h index 869bf6264d6a..07f5d064456c 100644 --- a/sound/usb/caiaq/audio.h +++ b/sound/usb/caiaq/audio.h @@ -3,6 +3,7 @@ #define CAIAQ_AUDIO_H

int snd_usb_caiaq_audio_init(struct snd_usb_caiaqdev *cdev); +void snd_usb_caiaq_audio_disconnect(struct snd_usb_caiaqdev *cdev); void snd_usb_caiaq_audio_free(struct snd_usb_caiaqdev *cdev);

#endif /* CAIAQ_AUDIO_H */ diff --git a/sound/usb/caiaq/device.c b/sound/usb/caiaq/device.c index d55ca48de3ea..4df7f37aa670 100644 --- a/sound/usb/caiaq/device.c +++ b/sound/usb/caiaq/device.c @@ -402,6 +402,17 @@ static void setup_card(struct snd_usb_caiaqdev *cdev) dev_err(dev, "Unable to set up control system (ret=%d)\n", ret); }

+static void card_free(struct snd_card *card) +{ + struct snd_usb_caiaqdev *cdev = caiaqdev(card); + +#ifdef CONFIG_SND_USB_CAIAQ_INPUT + snd_usb_caiaq_input_free(cdev); +#endif + snd_usb_caiaq_audio_free(cdev); + usb_reset_device(cdev->chip.dev); +} + static int create_card(struct usb_device *usb_dev, struct usb_interface *intf, struct snd_card **cardp) @@ -515,6 +526,7 @@ static int init_card(struct snd_usb_caiaqdev *cdev) cdev->vendor_name, cdev->product_name, usbpath);

setup_card(cdev); + card->private_free = card_free; return 0;

err_kill_urb: @@ -560,15 +572,14 @@ static void snd_disconnect(struct usb_interface *intf) snd_card_disconnect(card);

#ifdef CONFIG_SND_USB_CAIAQ_INPUT - snd_usb_caiaq_input_free(cdev); + snd_usb_caiaq_input_disconnect(cdev); #endif - snd_usb_caiaq_audio_free(cdev); + snd_usb_caiaq_audio_disconnect(cdev);

usb_kill_urb(&cdev->ep1_in_urb); usb_kill_urb(&cdev->midi_out_urb);

- snd_card_free(card); - usb_reset_device(interface_to_usbdev(intf)); + snd_card_free_when_closed(card); }

diff --git a/sound/usb/caiaq/input.c b/sound/usb/caiaq/input.c index e883659ea6e7..3adaf35b0c15 100644 --- a/sound/usb/caiaq/input.c +++ b/sound/usb/caiaq/input.c @@ -841,15 +841,21 @@ int snd_usb_caiaq_input_init(struct snd_usb_caiaqdev *cdev) return ret; }

-void snd_usb_caiaq_input_free(struct snd_usb_caiaqdev *cdev) +void snd_usb_caiaq_input_disconnect(struct snd_usb_caiaqdev *cdev) { if (!cdev || !cdev->input_dev) return;

usb_kill_urb(cdev->ep4_in_urb); + input_unregister_device(cdev->input_dev); +} + +void snd_usb_caiaq_input_free(struct snd_usb_caiaqdev *cdev) +{ + if (!cdev || !cdev->input_dev) + return; + usb_free_urb(cdev->ep4_in_urb); cdev->ep4_in_urb = NULL; - - input_unregister_device(cdev->input_dev); cdev->input_dev = NULL; } diff --git a/sound/usb/caiaq/input.h b/sound/usb/caiaq/input.h index c42891e7be88..fbe267f85d02 100644 --- a/sound/usb/caiaq/input.h +++ b/sound/usb/caiaq/input.h @@ -4,6 +4,7 @@

void snd_usb_caiaq_input_dispatch(struct snd_usb_caiaqdev *cdev, char *buf, unsigned int len); int snd_usb_caiaq_input_init(struct snd_usb_caiaqdev *cdev); +void snd_usb_caiaq_input_disconnect(struct snd_usb_caiaqdev *cdev); void snd_usb_caiaq_input_free(struct snd_usb_caiaqdev *cdev);

#endif