From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3BE832698AE; Tue, 8 Apr 2025 12:02:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744113729; cv=none; b=RByCs3J3Hp83G4jQxgZ8mERTX3cPVR3g99yEDQolgmKru621RMj7VvHZMYWNpIQV1tKYpj2o8ULPSFwH/BGi9acHJJ+JjU08mRASFdwyanL1QClmMYc3W7/rqa3gduKL2c5pn9v3ZqY5bvU0hXrra90VisiGEOAQWo0Cf/X8VHQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744113729; c=relaxed/simple; bh=4uqSQ0NOsZSFNqOoEr9TMmm55V0cXPM2fQL+puxih30=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DCRv9MRuZ+YptdLSH91TjxRF0mfnwMZ5HdWc0YOxiysMbiezmBPTJZJNddJ7503MYm+BCf8HR2Y9lFbshqCS5LnBjD1UijsefzXOzGk1OvUMG7NCgI0w9lyhzf796mGvsxhsXYJENQjTxaemJKtKbFtfMc1hjYNbzp6t1dMioWk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=SLYdJxTx; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="SLYdJxTx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BA889C4CEE5; Tue, 8 Apr 2025 12:02:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1744113729; bh=4uqSQ0NOsZSFNqOoEr9TMmm55V0cXPM2fQL+puxih30=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SLYdJxTxgDrOSAE7eyA4rtEnvcgnnamS3pMvg1ea7o+qJOoGwUT6jMGRoWQnlmUa1 vc649kzZZOiuLZU9cOHwceQeefZhei6s7ycMMmvmrwuVReYJU7VjuRvUzcP2dIwjtY o87toTruAsWpgV3dT2XtlcZ41u/AaDtJMD4Z/hdA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+34008406ee9a31b13c73@syzkaller.appspotmail.com, Murad Masimov , Sean Young , Hans Verkuil Subject: [PATCH 6.6 266/268] media: streamzap: fix race between device disconnection and urb callback Date: Tue, 8 Apr 2025 12:51:17 +0200 Message-ID: <20250408104835.750026099@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250408104828.499967190@linuxfoundation.org> References: <20250408104828.499967190@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Murad Masimov 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 Signed-off-by: Sean Young Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman --- drivers/media/rc/streamzap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/media/rc/streamzap.c +++ b/drivers/media/rc/streamzap.c @@ -385,8 +385,8 @@ static void streamzap_disconnect(struct 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);