From patchwork Tue Jan 5 19:47:52 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [01/10] Libertas: fix buffer overflow in lbs_get_essid() Date: Tue, 05 Jan 2010 09:47:52 -0000 From: gregkh@suse.de X-Patchwork-Id: 42169 Message-Id: <20100105194914.321801567@mini.kroah.org> To: linux-kernel@vger.kernel.org, stable@kernel.org, akpm@linux-foundation.org, torvalds@linux-foundation.org, stable-review@kernel.org Cc: Daniel Mack , Stephen Hemminger , Maithili Hinge , Kiran Divekar , Michael Hirsch , netdev@vger.kernel.org, libertas-dev@lists.infradead.org, linux-wireless@lists.infradead.org, Holger Schurig , Dan Williams , "John W. Linville" 2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ 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 file changed, 2 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html --- a/drivers/net/wireless/libertas/wext.c +++ b/drivers/net/wireless/libertas/wext.c @@ -1899,10 +1899,8 @@ static int lbs_get_essid(struct net_devi 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