Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754324Ab2JGXXE (ORCPT ); Sun, 7 Oct 2012 19:23:04 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:38406 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754082Ab2JGXWh (ORCPT ); Sun, 7 Oct 2012 19:22:37 -0400 Message-Id: <20121007225844.240289438@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Sun, 07 Oct 2012 23:59:43 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Matthieu CASTET , Jiri Kosina Subject: [ 069/108] HID: hidraw: fix list->buffer memleak In-Reply-To: <20121007225834.673681075@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2333 Lines: 76 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Matthieu CASTET commit 4c7b417ecb756e85dfc955b0e7a04fd45585533e upstream. If we don't read fast enough hidraw device, hidraw_report_event will cycle and we will leak list->buffer. Also list->buffer are not free on release. After this patch, kmemleak report nothing. Signed-off-by: Matthieu CASTET Signed-off-by: Jiri Kosina Signed-off-by: Ben Hutchings --- drivers/hid/hidraw.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/hid/hidraw.c b/drivers/hid/hidraw.c index 36fa77b..3b6f7bf 100644 --- a/drivers/hid/hidraw.c +++ b/drivers/hid/hidraw.c @@ -96,6 +96,7 @@ static ssize_t hidraw_read(struct file *file, char __user *buffer, size_t count, } kfree(list->buffer[list->tail].value); + list->buffer[list->tail].value = NULL; list->tail = (list->tail + 1) & (HIDRAW_BUFFER_SIZE - 1); } out: @@ -300,6 +301,7 @@ static int hidraw_release(struct inode * inode, struct file * file) struct hidraw *dev; struct hidraw_list *list = file->private_data; int ret; + int i; mutex_lock(&minors_lock); if (!hidraw_table[minor]) { @@ -317,6 +319,9 @@ static int hidraw_release(struct inode * inode, struct file * file) kfree(list->hidraw); } } + + for (i = 0; i < HIDRAW_BUFFER_SIZE; ++i) + kfree(list->buffer[i].value); kfree(list); ret = 0; unlock: @@ -446,12 +451,17 @@ int hidraw_report_event(struct hid_device *hid, u8 *data, int len) int ret = 0; list_for_each_entry(list, &dev->list, node) { + int new_head = (list->head + 1) & (HIDRAW_BUFFER_SIZE - 1); + + if (new_head == list->tail) + continue; + if (!(list->buffer[list->head].value = kmemdup(data, len, GFP_ATOMIC))) { ret = -ENOMEM; break; } list->buffer[list->head].len = len; - list->head = (list->head + 1) & (HIDRAW_BUFFER_SIZE - 1); + list->head = new_head; kill_fasync(&list->fasync, SIGIO, POLL_IN); } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/