From nobody Wed Oct 15 22:33:34 2025 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 6EB1C219555; Sun, 24 Mar 2024 23:35:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711323356; cv=none; b=iTLSCID0nlNSv8dNfcFMsY6n5tWIh9OX9WaPPrLCRQujSAyA0xnaEoXio+9wYFYadz7U3K+u8mHgar5IzRZ1rqVShxLwLuMRXMpM9CaHW5IfBUI93uwsGQR/D6nh+PZhCvLEZDAWiwx2SMehDANfqN02r1/D/S8Yc78pYzeRpew= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711323356; c=relaxed/simple; bh=AWr/EBV6VlandXtM4GSd7K0+kcZktDfJEz7DRks+Sys=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=ET7LvStpOevwdq8zGEGo3KZFRfY5JioJJI6CG2pMdXX0W7R54DktSf1jSIK59Sh0QZ/eAuLKhWIOlflwCDVD4/W7QGUOCjpOdP6dgXKI2LxGZROd+boni9W2RgtuRmHaqkNrwnannXlsu05NGQ2iJDz68Ug7ZhKj2lRGTY4gWHQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=vRr2W97e; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="vRr2W97e" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A9591C43390; Sun, 24 Mar 2024 23:35:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711323356; bh=AWr/EBV6VlandXtM4GSd7K0+kcZktDfJEz7DRks+Sys=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vRr2W97eto7EBGTS2q0IFFjwK82ZwlIO+v9MwR5+y3cWcqPs1oK2mjw2jhQ9wUUxW JIX6DIrZrVgEBmdMxCBCWkaVEM5nylR3ED8G1mhabPP3Z0dpLbUxuuiS25TJKcXQ1t FfzRfUTzxWfxjdPvOIGMDognOojmA1PYANy6st454tdztiSKJRa8ZSjry5Zc6udKaU gPBLW2yJUqOxAbzmN8CKuLdfoDofRB/zY2Cbm6WjD4LRl/x/bPIA+19YD1G0rkHr3q UvVoTBmCr812q3aFSB3DKoS/T3pT0EcmLolGMbtcr2VLCECKxYP/J1DAwzzDHskLTS iiSeE9ngotIag== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: =?UTF-8?q?Alexis=20Lothor=C3=A9?= , Kalle Valo , Sasha Levin Subject: [PATCH 5.15 056/317] wifi: wilc1000: fix RCU usage in connect path Date: Sun, 24 Mar 2024 19:30:36 -0400 Message-ID: <20240324233458.1352854-57-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240324233458.1352854-1-sashal@kernel.org> References: <20240324233458.1352854-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: quoted-printable From: Alexis Lothor=C3=A9 [ Upstream commit 205c50306acf58a335eb19fa84e40140f4fe814f ] With lockdep enabled, calls to the connect function from cfg802.11 layer lead to the following warning: =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D WARNING: suspicious RCU usage 6.7.0-rc1-wt+ #333 Not tainted ----------------------------- drivers/net/wireless/microchip/wilc1000/hif.c:386 suspicious rcu_dereference_check() usage! [...] stack backtrace: CPU: 0 PID: 100 Comm: wpa_supplicant Not tainted 6.7.0-rc1-wt+ #333 Hardware name: Atmel SAMA5 unwind_backtrace from show_stack+0x18/0x1c show_stack from dump_stack_lvl+0x34/0x48 dump_stack_lvl from wilc_parse_join_bss_param+0x7dc/0x7f4 wilc_parse_join_bss_param from connect+0x2c4/0x648 connect from cfg80211_connect+0x30c/0xb74 cfg80211_connect from nl80211_connect+0x860/0xa94 nl80211_connect from genl_rcv_msg+0x3fc/0x59c genl_rcv_msg from netlink_rcv_skb+0xd0/0x1f8 netlink_rcv_skb from genl_rcv+0x2c/0x3c genl_rcv from netlink_unicast+0x3b0/0x550 netlink_unicast from netlink_sendmsg+0x368/0x688 netlink_sendmsg from ____sys_sendmsg+0x190/0x430 ____sys_sendmsg from ___sys_sendmsg+0x110/0x158 ___sys_sendmsg from sys_sendmsg+0xe8/0x150 sys_sendmsg from ret_fast_syscall+0x0/0x1c This warning is emitted because in the connect path, when trying to parse target BSS parameters, we dereference a RCU pointer whithout being in RCU critical section. Fix RCU dereference usage by moving it to a RCU read critical section. To avoid wrapping the whole wilc_parse_join_bss_param under the critical section, just use the critical section to copy ies data Fixes: c460495ee072 ("staging: wilc1000: fix incorrent type in initializer") Signed-off-by: Alexis Lothor=C3=A9 Signed-off-by: Kalle Valo Link: https://msgid.link/20240105075733.36331-3-alexis.lothore@bootlin.com Signed-off-by: Sasha Levin --- drivers/net/wireless/microchip/wilc1000/hif.c | 36 ++++++++++++------- 1 file changed, 24 insertions(+), 12 deletions(-) diff --git a/drivers/net/wireless/microchip/wilc1000/hif.c b/drivers/net/wi= reless/microchip/wilc1000/hif.c index edd51592a82da..fe95a6201a679 100644 --- a/drivers/net/wireless/microchip/wilc1000/hif.c +++ b/drivers/net/wireless/microchip/wilc1000/hif.c @@ -359,38 +359,49 @@ static void handle_connect_timeout(struct work_struct= *work) void *wilc_parse_join_bss_param(struct cfg80211_bss *bss, struct cfg80211_crypto_settings *crypto) { - const struct cfg80211_bss_ies *ies =3D rcu_dereference(bss->ies); - const u8 *tim_elm, *ssid_elm, *rates_ie, *supp_rates_ie; + const u8 *ies_data, *tim_elm, *ssid_elm, *rates_ie, *supp_rates_ie; const u8 *ht_ie, *wpa_ie, *wmm_ie, *rsn_ie; struct ieee80211_p2p_noa_attr noa_attr; + const struct cfg80211_bss_ies *ies; struct wilc_join_bss_param *param; - u8 rates_len =3D 0; + u8 rates_len =3D 0, ies_len; int ret; =20 param =3D kzalloc(sizeof(*param), GFP_KERNEL); if (!param) return NULL; =20 + rcu_read_lock(); + ies =3D rcu_dereference(bss->ies); + ies_data =3D kmemdup(ies->data, ies->len, GFP_ATOMIC); + if (!ies_data) { + rcu_read_unlock(); + kfree(param); + return NULL; + } + ies_len =3D ies->len; + rcu_read_unlock(); + param->beacon_period =3D cpu_to_le16(bss->beacon_interval); param->cap_info =3D cpu_to_le16(bss->capability); param->bss_type =3D WILC_FW_BSS_TYPE_INFRA; param->ch =3D ieee80211_frequency_to_channel(bss->channel->center_freq); ether_addr_copy(param->bssid, bss->bssid); =20 - ssid_elm =3D cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len); + ssid_elm =3D cfg80211_find_ie(WLAN_EID_SSID, ies_data, ies_len); if (ssid_elm) { if (ssid_elm[1] <=3D IEEE80211_MAX_SSID_LEN) memcpy(param->ssid, ssid_elm + 2, ssid_elm[1]); } =20 - tim_elm =3D cfg80211_find_ie(WLAN_EID_TIM, ies->data, ies->len); + tim_elm =3D cfg80211_find_ie(WLAN_EID_TIM, ies_data, ies_len); if (tim_elm && tim_elm[1] >=3D 2) param->dtim_period =3D tim_elm[3]; =20 memset(param->p_suites, 0xFF, 3); memset(param->akm_suites, 0xFF, 3); =20 - rates_ie =3D cfg80211_find_ie(WLAN_EID_SUPP_RATES, ies->data, ies->len); + rates_ie =3D cfg80211_find_ie(WLAN_EID_SUPP_RATES, ies_data, ies_len); if (rates_ie) { rates_len =3D rates_ie[1]; if (rates_len > WILC_MAX_RATES_SUPPORTED) @@ -401,7 +412,7 @@ void *wilc_parse_join_bss_param(struct cfg80211_bss *bs= s, =20 if (rates_len < WILC_MAX_RATES_SUPPORTED) { supp_rates_ie =3D cfg80211_find_ie(WLAN_EID_EXT_SUPP_RATES, - ies->data, ies->len); + ies_data, ies_len); if (supp_rates_ie) { u8 ext_rates =3D supp_rates_ie[1]; =20 @@ -416,11 +427,11 @@ void *wilc_parse_join_bss_param(struct cfg80211_bss *= bss, } } =20 - ht_ie =3D cfg80211_find_ie(WLAN_EID_HT_CAPABILITY, ies->data, ies->len); + ht_ie =3D cfg80211_find_ie(WLAN_EID_HT_CAPABILITY, ies_data, ies_len); if (ht_ie) param->ht_capable =3D true; =20 - ret =3D cfg80211_get_p2p_attr(ies->data, ies->len, + ret =3D cfg80211_get_p2p_attr(ies_data, ies_len, IEEE80211_P2P_ATTR_ABSENCE_NOTICE, (u8 *)&noa_attr, sizeof(noa_attr)); if (ret > 0) { @@ -444,7 +455,7 @@ void *wilc_parse_join_bss_param(struct cfg80211_bss *bs= s, } wmm_ie =3D cfg80211_find_vendor_ie(WLAN_OUI_MICROSOFT, WLAN_OUI_TYPE_MICROSOFT_WMM, - ies->data, ies->len); + ies_data, ies_len); if (wmm_ie) { struct ieee80211_wmm_param_ie *ie; =20 @@ -459,13 +470,13 @@ void *wilc_parse_join_bss_param(struct cfg80211_bss *= bss, =20 wpa_ie =3D cfg80211_find_vendor_ie(WLAN_OUI_MICROSOFT, WLAN_OUI_TYPE_MICROSOFT_WPA, - ies->data, ies->len); + ies_data, ies_len); if (wpa_ie) { param->mode_802_11i =3D 1; param->rsn_found =3D true; } =20 - rsn_ie =3D cfg80211_find_ie(WLAN_EID_RSN, ies->data, ies->len); + rsn_ie =3D cfg80211_find_ie(WLAN_EID_RSN, ies_data, ies_len); if (rsn_ie) { int rsn_ie_len =3D sizeof(struct element) + rsn_ie[1]; int offset =3D 8; @@ -499,6 +510,7 @@ void *wilc_parse_join_bss_param(struct cfg80211_bss *bs= s, param->akm_suites[i] =3D crypto->akm_suites[i] & 0xFF; } =20 + kfree(ies_data); return (void *)param; } =20 --=20 2.43.0