From: Murad Masimov <m.masimov@mt-integration.ru> stable inclusion from stable-v6.6.87 commit 15483afb930fc2f883702dc96f80efbe4055235e category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IC1QRT CVE: CVE-2025-22027 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit f656cfbc7a293a039d6a0c7100e1c846845148c1 upstream. Syzkaller has reported a general protection fault at function ir_raw_event_store_with_filter(). This crash is caused by a NULL pointer dereference of dev->raw pointer, even though it is checked for NULL in the same function, which means there is a race condition. It occurs due to the incorrect order of actions in the streamzap_disconnect() function: rc_unregister_device() is called before usb_kill_urb(). The dev->raw pointer is freed and set to NULL in rc_unregister_device(), and only after that usb_kill_urb() waits for in-progress requests to finish. If rc_unregister_device() is called while streamzap_callback() handler is not finished, this can lead to accessing freed resources. Thus rc_unregister_device() should be called after usb_kill_urb(). Found by Linux Verification Center (linuxtesting.org) with Syzkaller. Fixes: 8e9e60640067 ("V4L/DVB: staging/lirc: port lirc_streamzap to ir-core") Cc: stable@vger.kernel.org Reported-by: syzbot+34008406ee9a31b13c73@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=34008406ee9a31b13c73 Signed-off-by: Murad Masimov <m.masimov@mt-integration.ru> Signed-off-by: Sean Young <sean@mess.org> Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Yi Yang <yiyang13@huawei.com> --- drivers/media/rc/streamzap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/rc/streamzap.c b/drivers/media/rc/streamzap.c index 9b209e687f25..2ce62fe5d60f 100644 --- a/drivers/media/rc/streamzap.c +++ b/drivers/media/rc/streamzap.c @@ -385,8 +385,8 @@ static void streamzap_disconnect(struct usb_interface *interface) if (!sz) return; - rc_unregister_device(sz->rdev); usb_kill_urb(sz->urb_in); + rc_unregister_device(sz->rdev); usb_free_urb(sz->urb_in); usb_free_coherent(usbdev, sz->buf_in_len, sz->buf_in, sz->dma_in); -- 2.25.1