From patchwork Tue Jan 5 00:32:52 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [39/97] Libertas: fix buffer overflow in lbs_get_essid() Date: Mon, 04 Jan 2010 14:32:52 -0000 From: gregkh@suse.de X-Patchwork-Id: 42105 Message-Id: <1262651630-7354-39-git-send-email-gregkh@suse.de> To: linux-kernel@vger.kernel.org, stable@kernel.org, stable-review@kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Daniel Mack , Stephen Hemminger , Maithili Hinge , Kiran Divekar , Michael Hirsch , netdev@vger.kernel.org, libertas-dev@lists.infradead.org, linux-wireless@lists.infradead.org, "John W. Linville" , Greg Kroah-Hartman From: Daniel Mack commit 45b241689179a6065384260242637cf21dabfb2d upstream. The libertas driver copies the SSID buffer back to the wireless core and appends a trailing NULL character for termination. This is a) unnecessary because the buffer is allocated with kzalloc and is hence already NULLed when this function is called, and b) for priv->curbssparams.ssid_len == 32, it writes back one byte too much which causes memory corruptions. Fix this by removing the extra write. Signed-off-by: Daniel Mack Cc: Stephen Hemminger Cc: Maithili Hinge Cc: Kiran Divekar Cc: Michael Hirsch Cc: netdev@vger.kernel.org Cc: libertas-dev@lists.infradead.org Cc: linux-wireless@lists.infradead.org Acked-by: Holger Schurig Acked-by: Dan Williams Signed-off-by: John W. Linville Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/libertas/wext.c | 2 -- 1 files changed, 0 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/libertas/wext.c b/drivers/net/wireless/libertas/wext.c index be837a0..01c738b 100644 --- a/drivers/net/wireless/libertas/wext.c +++ b/drivers/net/wireless/libertas/wext.c @@ -1953,10 +1953,8 @@ static int lbs_get_essid(struct net_device *dev, struct iw_request_info *info, if (priv->connect_status == LBS_CONNECTED) { memcpy(extra, priv->curbssparams.ssid, priv->curbssparams.ssid_len); - extra[priv->curbssparams.ssid_len] = '\0'; } else { memset(extra, 0, 32); - extra[priv->curbssparams.ssid_len] = '\0'; } /* * If none, we may want to get the one that was set