From patchwork Mon Dec 4 15:55:37 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Antipov X-Patchwork-Id: 751045 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=yandex.ru header.i=@yandex.ru header.b="wiRTziqT" Received: from forward100c.mail.yandex.net (forward100c.mail.yandex.net [178.154.239.211]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B7DC6A4 for ; Mon, 4 Dec 2023 07:56:23 -0800 (PST) Received: from mail-nwsmtp-smtp-production-main-57.myt.yp-c.yandex.net (mail-nwsmtp-smtp-production-main-57.myt.yp-c.yandex.net [IPv6:2a02:6b8:c12:2612:0:640:2e49:0]) by forward100c.mail.yandex.net (Yandex) with ESMTP id 7322A60036; Mon, 4 Dec 2023 18:56:21 +0300 (MSK) Received: by mail-nwsmtp-smtp-production-main-57.myt.yp-c.yandex.net (smtp/Yandex) with ESMTPSA id KucJcIOn9iE0-BA8yVF0i; Mon, 04 Dec 2023 18:56:20 +0300 X-Yandex-Fwd: 1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex.ru; s=mail; t=1701705380; bh=hgJ1dv8lCdDXqdsTAJUZOMd60URy+PklyC8vyq5AcHc=; h=Message-ID:Date:Cc:Subject:To:From; b=wiRTziqTzPz3g2yt7MAewtpDvsv1MGaAjLDeuj4Jp2jqS0pzshI4ySk8AHDZHmZuy Suv3RNOQVSRGxtiG4G7RCxC91tDniKnzb5oi/DUsCvpoL+PaFmHgdjWZjFoeahMbgK 4cFtvKv1DcoGUsffeqV0mikIX5IxDtJ4rb4/oa5A= Authentication-Results: mail-nwsmtp-smtp-production-main-57.myt.yp-c.yandex.net; dkim=pass header.i=@yandex.ru From: Dmitry Antipov To: =?utf-8?b?SsOpcsO0bWUgUG91aWxsZXI=?= Cc: Kalle Valo , linux-wireless@vger.kernel.org, Dmitry Antipov Subject: [PATCH] wifi: wfx: fix possible NULL pointer dereference in wfx_set_mfp_ap() Date: Mon, 4 Dec 2023 18:55:37 +0300 Message-ID: <20231204155558.133839-1-dmantipov@yandex.ru> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Since 'ieee80211_beacon_get()' can return NULL, 'wfx_set_mfp_ap()' should check the return value before examining skb data. So convert the latter to return an appropriate error code and propagate it to return from 'wfx_start_ap()' as well. Compile tested only. Signed-off-by: Dmitry Antipov --- drivers/net/wireless/silabs/wfx/sta.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/drivers/net/wireless/silabs/wfx/sta.c b/drivers/net/wireless/silabs/wfx/sta.c index 1b6c158457b4..df100d8513ad 100644 --- a/drivers/net/wireless/silabs/wfx/sta.c +++ b/drivers/net/wireless/silabs/wfx/sta.c @@ -336,29 +336,35 @@ static int wfx_upload_ap_templates(struct wfx_vif *wvif) return 0; } -static void wfx_set_mfp_ap(struct wfx_vif *wvif) +static int wfx_set_mfp_ap(struct wfx_vif *wvif) { struct ieee80211_vif *vif = wvif_to_vif(wvif); struct sk_buff *skb = ieee80211_beacon_get(wvif->wdev->hw, vif, 0); const int ieoffset = offsetof(struct ieee80211_mgmt, u.beacon.variable); - const u16 *ptr = (u16 *)cfg80211_find_ie(WLAN_EID_RSN, skb->data + ieoffset, - skb->len - ieoffset); const int pairwise_cipher_suite_count_offset = 8 / sizeof(u16); const int pairwise_cipher_suite_size = 4 / sizeof(u16); const int akm_suite_size = 4 / sizeof(u16); + const u16 *ptr; + if (unlikely(!skb)) + return -ENOMEM; + + ptr = (u16 *)cfg80211_find_ie(WLAN_EID_RSN, skb->data + ieoffset, + skb->len - ieoffset); if (ptr) { ptr += pairwise_cipher_suite_count_offset; if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) - return; + return -EINVAL; ptr += 1 + pairwise_cipher_suite_size * *ptr; if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) - return; + return -EINVAL; ptr += 1 + akm_suite_size * *ptr; if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) - return; + return -EINVAL; wfx_hif_set_mfp(wvif, *ptr & BIT(7), *ptr & BIT(6)); + return 0; } + return -EINVAL; } int wfx_start_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif, @@ -374,10 +380,7 @@ int wfx_start_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif, wvif = (struct wfx_vif *)vif->drv_priv; wfx_upload_ap_templates(wvif); ret = wfx_hif_start(wvif, &vif->bss_conf, wvif->channel); - if (ret > 0) - return -EIO; - wfx_set_mfp_ap(wvif); - return ret; + return ret > 0 ? -EIO : wfx_set_mfp_ap(wvif); } void wfx_stop_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif,