From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nico Golde , Fabian Yamaguchi , Dan Carpenter , Dan Williams , "John W. Linville" , Kees Cook Subject: [PATCH 3.4 03/39] libertas: potential oops in debugfs Date: Tue, 26 Nov 2013 16:56:27 -0800 Message-Id: <20131127005619.287770936@linuxfoundation.org> In-Reply-To: <20131127005619.011763867@linuxfoundation.org> References: <20131127005619.011763867@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter commit a497e47d4aec37aaf8f13509f3ef3d1f6a717d88 upstream. If we do a zero size allocation then it will oops. Also we can't be sure the user passes us a NUL terminated string so I've added a terminator. This code can only be triggered by root. Reported-by: Nico Golde Reported-by: Fabian Yamaguchi Signed-off-by: Dan Carpenter Acked-by: Dan Williams Signed-off-by: John W. Linville Cc: Kees Cook Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/libertas/debugfs.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/drivers/net/wireless/libertas/debugfs.c +++ b/drivers/net/wireless/libertas/debugfs.c @@ -913,7 +913,10 @@ static ssize_t lbs_debugfs_write(struct char *p2; struct debug_data *d = f->private_data; - pdata = kmalloc(cnt, GFP_KERNEL); + if (cnt == 0) + return 0; + + pdata = kmalloc(cnt + 1, GFP_KERNEL); if (pdata == NULL) return 0; @@ -922,6 +925,7 @@ static ssize_t lbs_debugfs_write(struct kfree(pdata); return 0; } + pdata[cnt] = '\0'; p0 = pdata; for (i = 0; i < num_of_items; i++) {