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 DEC2A347BD9; Wed, 3 Dec 2025 16:15:23 +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=1764778524; cv=none; b=UiPze7pJpvyYmbG9HqCGLGyatvLp1XEZm+W3GSazQjyvA7uJB6pOYKVHngwAg3P167JpX9b44FcQ1fjuqbbrwbAowWrsEhHJi60k/8CsEoQvuym85cY5QWSKI3ouPTn3Z4uAcoEj9rHTXtQ5LSu5J6tL2qXDJGYDMmgwi9FqoTg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764778524; c=relaxed/simple; bh=Ke7G48pcPMFmzxvNM/zfFLJPUBCn26VMfJ3dYAHLGOY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cOczKLaMuKhkNl5ZljGyjxdOnp9udEY0F0JDxgscpEFoPnAJraR21ms4RfSl8ueYZ9Ip2AvTUEJYW6JaiUX44Z5PpmZUx3X0n76e3WZ298g/amCHMTGNlRdaXLVL8sGfx06ahw9mmhNdAQKR3p9TpIzJVolGIrld+u1Vx/QujbY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Dw6vJyVX; 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="Dw6vJyVX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 67B26C4CEF5; Wed, 3 Dec 2025 16:15:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1764778523; bh=Ke7G48pcPMFmzxvNM/zfFLJPUBCn26VMfJ3dYAHLGOY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Dw6vJyVXhM+HFQREfQ01qMFeI7Zae2yG6T48PlxlXDc7bdBU6BdRwNxcNsiLHrem9 ubAvFwXze8QwAt+Yoqk0vgd3Yb7pN/QY/AlerSfqvveZqGuXYMLnGT5fYLbZFvtVJN iygi/bsbuMC1NXLj2weLqcfwi5psS4yHNPjHx7Yk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable , Thinh Nguyen , Manish Nagar Subject: [PATCH 5.15 371/392] usb: dwc3: Fix race condition between concurrent dwc3_remove_requests() call paths Date: Wed, 3 Dec 2025 16:28:41 +0100 Message-ID: <20251203152427.810121204@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251203152414.082328008@linuxfoundation.org> References: <20251203152414.082328008@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Manish Nagar commit e4037689a366743c4233966f0e74bc455820d316 upstream. This patch addresses a race condition caused by unsynchronized execution of multiple call paths invoking `dwc3_remove_requests()`, leading to premature freeing of USB requests and subsequent crashes. Three distinct execution paths interact with `dwc3_remove_requests()`: Path 1: Triggered via `dwc3_gadget_reset_interrupt()` during USB reset handling. The call stack includes: - `dwc3_ep0_reset_state()` - `dwc3_ep0_stall_and_restart()` - `dwc3_ep0_out_start()` - `dwc3_remove_requests()` - `dwc3_gadget_del_and_unmap_request()` Path 2: Also initiated from `dwc3_gadget_reset_interrupt()`, but through `dwc3_stop_active_transfers()`. The call stack includes: - `dwc3_stop_active_transfers()` - `dwc3_remove_requests()` - `dwc3_gadget_del_and_unmap_request()` Path 3: Occurs independently during `adb root` execution, which triggers USB function unbind and bind operations. The sequence includes: - `gserial_disconnect()` - `usb_ep_disable()` - `dwc3_gadget_ep_disable()` - `dwc3_remove_requests()` with `-ESHUTDOWN` status Path 3 operates asynchronously and lacks synchronization with Paths 1 and 2. When Path 3 completes, it disables endpoints and frees 'out' requests. If Paths 1 or 2 are still processing these requests, accessing freed memory leads to a crash due to use-after-free conditions. To fix this added check for request completion and skip processing if already completed and added the request status for ep0 while queue. Fixes: 72246da40f37 ("usb: Introduce DesignWare USB3 DRD Driver") Cc: stable Suggested-by: Thinh Nguyen Acked-by: Thinh Nguyen Signed-off-by: Manish Nagar Link: https://patch.msgid.link/20251120074435.1983091-1-manish.nagar@oss.qualcomm.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/dwc3/ep0.c | 1 + drivers/usb/dwc3/gadget.c | 7 +++++++ 2 files changed, 8 insertions(+) --- a/drivers/usb/dwc3/ep0.c +++ b/drivers/usb/dwc3/ep0.c @@ -92,6 +92,7 @@ static int __dwc3_gadget_ep0_queue(struc req->request.actual = 0; req->request.status = -EINPROGRESS; req->epnum = dep->number; + req->status = DWC3_REQUEST_STATUS_QUEUED; list_add_tail(&req->list, &dep->pending_list); --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -229,6 +229,13 @@ void dwc3_gadget_giveback(struct dwc3_ep { struct dwc3 *dwc = dep->dwc; + /* + * The request might have been processed and completed while the + * spinlock was released. Skip processing if already completed. + */ + if (req->status == DWC3_REQUEST_STATUS_COMPLETED) + return; + dwc3_gadget_del_and_unmap_request(dep, req, status); req->status = DWC3_REQUEST_STATUS_COMPLETED;