Return-path: Received: from mail-wi0-f181.google.com ([209.85.212.181]:36768 "EHLO mail-wi0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932397AbbEWUOS (ORCPT ); Sat, 23 May 2015 16:14:18 -0400 From: Haggai Eran To: Larry Finger Cc: Haggai Eran , Florian Schilhabel , Greg Kroah-Hartman , linux-wireless@vger.kernel.org, Subject: [PATCH v1] staging: rtl8712: prevent buffer overrun in recvbuf2recvframe Date: Sat, 23 May 2015 23:13:51 +0300 Message-Id: <1432412031-12871-1-git-send-email-haggai.eran@gmail.com> (sfid-20150523_221422_451141_263C519A) Sender: linux-wireless-owner@vger.kernel.org List-ID: With an RTL8191SU USB adaptor, sometimes the hints for a fragmented packet are set, but the packet length is too large. Allocate enough space to prevent memory corruption and a resulting kernel panic [1]. [1] http://www.spinics.net/lists/linux-wireless/msg136546.html Cc: Signed-off-by: Haggai Eran --- Hi Larry, I've updated the patch to avoid truncating the packets. I'm keeping the minimal buffer of 1658 bytes in case some other device does rely on this defragmentation feature. Regards, Haggai drivers/staging/rtl8712/rtl8712_recv.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/staging/rtl8712/rtl8712_recv.c b/drivers/staging/rtl8712/rtl8712_recv.c index cd8b444..5542243 100644 --- a/drivers/staging/rtl8712/rtl8712_recv.c +++ b/drivers/staging/rtl8712/rtl8712_recv.c @@ -1056,7 +1056,8 @@ static int recvbuf2recvframe(struct _adapter *padapter, struct sk_buff *pskb) /* for first fragment packet, driver need allocate 1536 + * drvinfo_sz + RXDESC_SIZE to defrag packet. */ if ((mf == 1) && (frag == 0)) - alloc_sz = 1658;/*1658+6=1664, 1664 is 128 alignment.*/ + /*1658+6=1664, 1664 is 128 alignment.*/ + alloc_sz = max_t(u16, tmp_len, 1658); else alloc_sz = tmp_len; /* 2 is for IP header 4 bytes alignment in QoS packet case. -- 1.9.1