From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755396Ab3LQSNt (ORCPT ); Tue, 17 Dec 2013 13:13:49 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:60677 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755356Ab3LQSNm (ORCPT ); Tue, 17 Dec 2013 13:13:42 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Mauro Carvalho Chehab , Luis Henriques Subject: [PATCH 3.5 001/103] [media] lirc_zilog: Don't use dynamic static allocation Date: Tue, 17 Dec 2013 18:11:50 +0000 Message-Id: <1387304012-23805-2-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1387304012-23805-1-git-send-email-luis.henriques@canonical.com> References: <1387304012-23805-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.5.7.28 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Mauro Carvalho Chehab commit ac5b4b6bf0c84c48d7e2e3fce22e35b04282ba76 upstream. Dynamic static allocation is evil, as Kernel stack is too low, and ompilation complains about it on some archs: drivers/staging/media/lirc/lirc_zilog.c:967:1: warning: 'read' uses dynamic stack allocation [enabled by default] Instead, let's enforce a limit for the buffer to be 64. That should be more than enough. Signed-off-by: Mauro Carvalho Chehab Reviewed-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Luis Henriques --- drivers/staging/media/lirc/lirc_zilog.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/staging/media/lirc/lirc_zilog.c b/drivers/staging/media/lirc/lirc_zilog.c index 76ea4a8..56a96d3 100644 --- a/drivers/staging/media/lirc/lirc_zilog.c +++ b/drivers/staging/media/lirc/lirc_zilog.c @@ -61,6 +61,9 @@ #include #include +/* Max transfer size done by I2C transfer functions */ +#define MAX_XFER_SIZE 64 + struct IR; struct IR_rx { @@ -942,7 +945,14 @@ static ssize_t read(struct file *filep, char *outbuf, size_t n, loff_t *ppos) schedule(); set_current_state(TASK_INTERRUPTIBLE); } else { - unsigned char buf[rbuf->chunk_size]; + unsigned char buf[MAX_XFER_SIZE]; + + if (rbuf->chunk_size > sizeof(buf)) { + zilog_error("chunk_size is too big (%d)!\n", + rbuf->chunk_size); + ret = -EINVAL; + break; + } m = lirc_buffer_read(rbuf, buf); if (m == rbuf->chunk_size) { ret = copy_to_user((void *)outbuf+written, buf, -- 1.8.3.2