From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EEA75E95A91 for ; Mon, 9 Oct 2023 13:32:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377113AbjJINcc (ORCPT ); Mon, 9 Oct 2023 09:32:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51628 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1377117AbjJINcb (ORCPT ); Mon, 9 Oct 2023 09:32:31 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6CE11B7 for ; Mon, 9 Oct 2023 06:32:27 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A8FD5C433CA; Mon, 9 Oct 2023 13:32:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1696858347; bh=uA4Ii6thaw1RKyKoG7hU5wA4BgxApKPt9F5KZtqsNJg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IervZeCo4cwciXNgHKmdjFJfjuBTul0vYArh1LgbjKi/dhXksHNUIvZv0g+DYMzku NH5BJQX9yqMtvxhImSDzQZ0eebr9IlplBsRxAWY0HVqYpnDMJ1JCaQxQb01ze5g6wi hnF6gVT3gmj0i9M+PgQjzIHpv9wKTq4trcQanzhw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Gustavo A. R. Silva" , Kees Cook , Kalle Valo Subject: [PATCH 5.4 093/131] wifi: mwifiex: Fix tlv_buf_left calculation Date: Mon, 9 Oct 2023 15:02:13 +0200 Message-ID: <20231009130119.233415785@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231009130116.329529591@linuxfoundation.org> References: <20231009130116.329529591@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gustavo A. R. Silva commit eec679e4ac5f47507774956fb3479c206e761af7 upstream. In a TLV encoding scheme, the Length part represents the length after the header containing the values for type and length. In this case, `tlv_len` should be: tlv_len == (sizeof(*tlv_rxba) - 1) - sizeof(tlv_rxba->header) + tlv_bitmap_len Notice that the `- 1` accounts for the one-element array `bitmap`, which 1-byte size is already included in `sizeof(*tlv_rxba)`. So, if the above is correct, there is a double-counting of some members in `struct mwifiex_ie_types_rxba_sync`, when `tlv_buf_left` and `tmp` are calculated: 968 tlv_buf_left -= (sizeof(*tlv_rxba) + tlv_len); 969 tmp = (u8 *)tlv_rxba + tlv_len + sizeof(*tlv_rxba); in specific, members: drivers/net/wireless/marvell/mwifiex/fw.h:777 777 u8 mac[ETH_ALEN]; 778 u8 tid; 779 u8 reserved; 780 __le16 seq_num; 781 __le16 bitmap_len; This is clearly wrong, and affects the subsequent decoding of data in `event_buf` through `tlv_rxba`: 970 tlv_rxba = (struct mwifiex_ie_types_rxba_sync *)tmp; Fix this by using `sizeof(tlv_rxba->header)` instead of `sizeof(*tlv_rxba)` in the calculation of `tlv_buf_left` and `tmp`. This results in the following binary differences before/after changes: | drivers/net/wireless/marvell/mwifiex/11n_rxreorder.o | @@ -4698,11 +4698,11 @@ | drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c:968 | tlv_buf_left -= (sizeof(tlv_rxba->header) + tlv_len); | - 1da7: lea -0x11(%rbx),%edx | + 1da7: lea -0x4(%rbx),%edx | 1daa: movzwl %bp,%eax | drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c:969 | tmp = (u8 *)tlv_rxba + sizeof(tlv_rxba->header) + tlv_len; | - 1dad: lea 0x11(%r15,%rbp,1),%r15 | + 1dad: lea 0x4(%r15,%rbp,1),%r15 The above reflects the desired change: avoid counting 13 too many bytes; which is the total size of the double-counted members in `struct mwifiex_ie_types_rxba_sync`: $ pahole -C mwifiex_ie_types_rxba_sync drivers/net/wireless/marvell/mwifiex/11n_rxreorder.o struct mwifiex_ie_types_rxba_sync { struct mwifiex_ie_types_header header; /* 0 4 */ |----------------------------------------------------------------------- | u8 mac[6]; /* 4 6 */ | | u8 tid; /* 10 1 */ | | u8 reserved; /* 11 1 */ | | __le16 seq_num; /* 12 2 */ | | __le16 bitmap_len; /* 14 2 */ | | u8 bitmap[1]; /* 16 1 */ | |----------------------------------------------------------------------| | 13 bytes| ----------- /* size: 17, cachelines: 1, members: 7 */ /* last cacheline: 17 bytes */ } __attribute__((__packed__)); Fixes: 99ffe72cdae4 ("mwifiex: process rxba_sync event") Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva Reviewed-by: Kees Cook Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/06668edd68e7a26bbfeebd1201ae077a2a7a8bce.1692931954.git.gustavoars@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c +++ b/drivers/net/wireless/marvell/mwifiex/11n_rxreorder.c @@ -977,8 +977,8 @@ void mwifiex_11n_rxba_sync_event(struct } } - tlv_buf_left -= (sizeof(*tlv_rxba) + tlv_len); - tmp = (u8 *)tlv_rxba + tlv_len + sizeof(*tlv_rxba); + tlv_buf_left -= (sizeof(tlv_rxba->header) + tlv_len); + tmp = (u8 *)tlv_rxba + sizeof(tlv_rxba->header) + tlv_len; tlv_rxba = (struct mwifiex_ie_types_rxba_sync *)tmp; } }