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, Kees Cook , Oded Horovitz , Brad Spengler , Matt Carlson , "David S. Miller" Subject: [ 18/68] tg3: fix length overflow in VPD firmware parsing Date: Tue, 2 Apr 2013 15:13:07 -0700 Message-Id: <20130402221332.045800853@linuxfoundation.org> In-Reply-To: <20130402221329.915209206@linuxfoundation.org> References: <20130402221329.915209206@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: Kees Cook commit 715230a44310a8cf66fbfb5a46f9a62a9b2de424 upstream. Commit 184b89044fb6e2a74611dafa69b1dce0d98612c6 ("tg3: Use VPD fw version when present") introduced VPD parsing that contained a potential length overflow. Limit the hardware's reported firmware string length (max 255 bytes) to stay inside the driver's firmware string length (32 bytes). On overflow, truncate the formatted firmware string instead of potentially overwriting portions of the tg3 struct. http://cansecwest.com/slides/2013/PrivateCore%20CSW%202013.pdf Signed-off-by: Kees Cook Reported-by: Oded Horovitz Reported-by: Brad Spengler Cc: Matt Carlson Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/broadcom/tg3.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/drivers/net/ethernet/broadcom/tg3.c +++ b/drivers/net/ethernet/broadcom/tg3.c @@ -13590,8 +13590,11 @@ static void __devinit tg3_read_vpd(struc if (j + len > block_end) goto partno; - memcpy(tp->fw_ver, &vpd_data[j], len); - strncat(tp->fw_ver, " bc ", vpdlen - len - 1); + if (len >= sizeof(tp->fw_ver)) + len = sizeof(tp->fw_ver) - 1; + memset(tp->fw_ver, 0, sizeof(tp->fw_ver)); + snprintf(tp->fw_ver, sizeof(tp->fw_ver), "%.*s bc ", len, + &vpd_data[j]); } partno: