From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 3140B4746A9; Sat, 12 Sep 2026 11:50:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789213852; cv=none; b=MYApZ7GMOUlHTF8AesAQpkAA/cPeSYjgCGCJV3JyIE7WqMyuBh4gNr2jacbpsn498l6/2NHtZUOBwQAD23IHsYlPRdqBGTSNIhFjcyypkjKriuHned+Pcyows60H1rmo7rrowg13Y2lbJyxg/jQl6a4pjLuNKWRBEArFSFVpO2E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789213852; c=relaxed/simple; bh=6C2OMe3iKDHuBBFVXag6bLNe9MqoIExuxg1IU1X+x7A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=A4VNVhLuRI54G33RxegyLWqLX+Iriil5Is/3ADOVXlAnDCmsrRcFEpQGN+ZWwRB7MUH6+5oCJiEGWRCdMPhEwoDFeK90gDfAeypUOCEzv56mrh9BnPpyRDC4qAhx/CUdo7plFWV+X4YwlhZeKuLM6HI7mawuYg15D8ZKAIPYo1U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=bLk6YEuR; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="bLk6YEuR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BB0221F000FF; Sat, 12 Sep 2026 11:50:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789213850; bh=uM7iy7aSUqcKn//qaTZho6nT0g0inb5tK4kMcD7fBFs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=bLk6YEuRVID8s5dMIjC6aUuJPKgv/f0ULJbNsV19OB7VkAP7obuDYCRvR56syWbEI th8vM3xXm6/GK0HN6FcNxDGvuFtt0yPW1M67UWxrYA/8QHSyNt4RhsF9nzQhTQWFCG bgFaqE1stSugslxyxwbolxLX04uHhsGzWQxigY2M= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Valery Borovsky , Hans Verkuil Subject: [PATCH 6.12 0206/1376] media: rtl2832_sdr: release URBs and stream buffers on start_streaming() failure Date: Sat, 12 Sep 2026 08:43:52 +0200 Message-ID: <20260912065612.141811312@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065607.535295758@linuxfoundation.org> References: <20260912065607.535295758@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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Valery Borovsky commit fe50cdaebf12cd32ff9a44d92bfd6fbc2300dbd4 upstream. rtl2832_sdr_start_streaming() calls rtl2832_sdr_alloc_stream_bufs(), rtl2832_sdr_alloc_urbs() and rtl2832_sdr_submit_urbs() in sequence and shares a single err: label that only unlocks the mutex and returns. When alloc_urbs() succeeds but submit_urbs() fails, or when alloc_urbs() itself returns -ENOMEM after alloc_stream_bufs() has already succeeded, the URBs and/or the coherent DMA stream buffers stay allocated while streaming reports failure to vb2. Two latent defects follow on the next VIDIOC_STREAMON: 1) rtl2832_sdr_alloc_stream_bufs() unconditionally resets dev->buf_num to 0 and overwrites dev->buf_list[]/dev->dma_addr[], permanently leaking the coherent DMA memory allocated by the previous attempt. 2) rtl2832_sdr_alloc_urbs() never resets dev->urbs_initialized and only increments it. After a second successful pass urbs_initialized can exceed MAX_BULK_BUFS, so the subsequent rtl2832_sdr_free_urbs() walks from urbs_initialized - 1 down to 0 and reads past the end of dev->urb_list[], passing garbage pointers to usb_free_urb(). Mirror the teardown that stop_streaming() already performs: on the error path call rtl2832_sdr_free_urbs() and rtl2832_sdr_free_stream_bufs() before unlocking. Both helpers are idempotent (free_urbs kills and zeros urbs_initialized; free_stream_bufs is gated on URB_BUF and clears the buf_num counter), so partial-failure paths and the no-allocation paths remain safe. Issue identified by automated review of the INV-003 series at https://sashiko.dev/ Fixes: 771138920eaf ("[media] rtl2832_sdr: Realtek RTL2832 SDR driver module") Cc: stable@vger.kernel.org Signed-off-by: Valery Borovsky Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman --- drivers/media/dvb-frontends/rtl2832_sdr.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/media/dvb-frontends/rtl2832_sdr.c +++ b/drivers/media/dvb-frontends/rtl2832_sdr.c @@ -906,9 +906,12 @@ static int rtl2832_sdr_start_streaming(s goto err; mutex_unlock(&dev->v4l2_lock); + return 0; err: + rtl2832_sdr_free_urbs(dev); + rtl2832_sdr_free_stream_bufs(dev); rtl2832_sdr_cleanup_queued_bufs(dev, VB2_BUF_STATE_QUEUED); mutex_unlock(&dev->v4l2_lock);