From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BD2EF18654 for ; Wed, 20 Sep 2023 11:46:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3D54EC433CA; Wed, 20 Sep 2023 11:46:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1695210401; bh=mwW68LAQLescnG4lH+xSTw6A2T8ZEm6hTaBLAOMomwU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=a86XxOB3ct/p6hVmTJ9ljRPSr5/wNtCsq1d50Il5lz21fceiLjpBZgE5Wo9kvicL2 s1Nl6wj8JFXfXl0qv72eF5HjaUy0myMwuuaBNha+1j8TtspaziFPHY9PUtq0ZUpQom qfxpmjweCmET76rPZZbU6YiATbN0PWL5UoOYiZok= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Brian Norris , Dmitry Antipov , Kalle Valo , Sasha Levin Subject: [PATCH 6.5 030/211] wifi: mwifiex: fix fortify warning Date: Wed, 20 Sep 2023 13:27:54 +0200 Message-ID: <20230920112846.731632761@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230920112845.859868994@linuxfoundation.org> References: <20230920112845.859868994@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dmitry Antipov [ Upstream commit dcce94b80a954a8968ff29fafcfb066d6197fa9a ] When compiling with gcc 13.1 and CONFIG_FORTIFY_SOURCE=y, I've noticed the following: In function ‘fortify_memcpy_chk’, inlined from ‘mwifiex_construct_tdls_action_frame’ at drivers/net/wireless/marvell/mwifiex/tdls.c:765:3, inlined from ‘mwifiex_send_tdls_action_frame’ at drivers/net/wireless/marvell/mwifiex/tdls.c:856:6: ./include/linux/fortify-string.h:529:25: warning: call to ‘__read_overflow2_field’ declared with attribute warning: detected read beyond size of field (2nd parameter); maybe use struct_group()? [-Wattribute-warning] 529 | __read_overflow2_field(q_size_field, size); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The compiler actually complains on: memmove(pos + ETH_ALEN, &mgmt->u.action.category, sizeof(mgmt->u.action.u.tdls_discover_resp)); and it happens because the fortification logic interprets this as an attempt to overread 1-byte 'u.action.category' member of 'struct ieee80211_mgmt'. To silence this warning, it's enough to pass an address of 'u.action' itself instead of an address of its first member. This also fixes an improper usage of 'sizeof()'. Since 'skb' is extended with 'sizeof(mgmt->u.action.u.tdls_discover_resp) + 1' bytes (where 1 is actually 'sizeof(mgmt->u.action.category)'), I assume that the same number of bytes should be copied. Suggested-by: Brian Norris Signed-off-by: Dmitry Antipov Reviewed-by: Brian Norris Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20230629085115.180499-2-dmantipov@yandex.ru Signed-off-by: Sasha Levin --- drivers/net/wireless/marvell/mwifiex/tdls.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/marvell/mwifiex/tdls.c b/drivers/net/wireless/marvell/mwifiex/tdls.c index 97bb87c3676bb..6c60621b6cccb 100644 --- a/drivers/net/wireless/marvell/mwifiex/tdls.c +++ b/drivers/net/wireless/marvell/mwifiex/tdls.c @@ -735,6 +735,7 @@ mwifiex_construct_tdls_action_frame(struct mwifiex_private *priv, int ret; u16 capab; struct ieee80211_ht_cap *ht_cap; + unsigned int extra; u8 radio, *pos; capab = priv->curr_bss_params.bss_descriptor.cap_info_bitmap; @@ -753,7 +754,10 @@ mwifiex_construct_tdls_action_frame(struct mwifiex_private *priv, switch (action_code) { case WLAN_PUB_ACTION_TDLS_DISCOVER_RES: - skb_put(skb, sizeof(mgmt->u.action.u.tdls_discover_resp) + 1); + /* See the layout of 'struct ieee80211_mgmt'. */ + extra = sizeof(mgmt->u.action.u.tdls_discover_resp) + + sizeof(mgmt->u.action.category); + skb_put(skb, extra); mgmt->u.action.category = WLAN_CATEGORY_PUBLIC; mgmt->u.action.u.tdls_discover_resp.action_code = WLAN_PUB_ACTION_TDLS_DISCOVER_RES; @@ -762,8 +766,7 @@ mwifiex_construct_tdls_action_frame(struct mwifiex_private *priv, mgmt->u.action.u.tdls_discover_resp.capability = cpu_to_le16(capab); /* move back for addr4 */ - memmove(pos + ETH_ALEN, &mgmt->u.action.category, - sizeof(mgmt->u.action.u.tdls_discover_resp)); + memmove(pos + ETH_ALEN, &mgmt->u.action, extra); /* init address 4 */ eth_broadcast_addr(pos); -- 2.40.1