From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793212888; b=x/iUcd5fr4zaNLOM6LC8y8vau8f9M12GEpai/LBil2WA6iGqWe2Xe9eABRx7aoA8yAiM /annotEKr5k/D88Q6zv4dyIyMBCfpJ6B0TwKK2+1CP6etshALPRgGFTUKukM0VrIVw7MJ 0WS7P1xlPXjIEvmfPcd3ASB/QeIDsk/EHIvjlGWWXU216twNp1eL5ErqqDUJ9ZwdP9owC PR4LKB+qFc+TkJZJnEsyRurTcvljFAcwKIb/6uwU0x49d9kP3Cd4oIL+hJSPncxf19ggT Bd20e1QkfO1oeTAjoioyk9oeIHADqT1CfOB659ExyoJhn81oSz3vZCetujxcruKo0bw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793212888; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=prvLrKO4GUizS34XOWHdQI0z1DqWdkfwwuHXFxOy6DM=; b=KsqEebTnje4aej0D9fcftsOBfI4TosscsbHbuxoj+pn1RXTDTVHXiuUP4K69aSOxo3vJ U0zRBQBiIZ99Wo15IuRFRI7VhyjjiWAp5buakEY/63oX4K518gNZyFSN4nRrYeLcAYil2 wjEzkop2tkZxg+bQsLStSxxwpNeJbg42VQ4v8uDlwDmUZymkJj4nGR/XUsDalkh1/hGQm BkK5znj+V7kYne4ZIyZj72Z0LL1D+iSSfPTxEGuN4RhouRbn8KabOJveRXxX4DzC1I/De 5s0oZuEvNOMGuhal0EAByKi7+ivlQ0SJHHOwuXgEFFIB1F/+Qhx1j6kgnPn2OXK4pqA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=lgAwMXNx; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 75EF0606A31D; Wed, 28 Oct 2026 18:41:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=lgAwMXNx Received: by smtp.kernel.org (Postfix) with ESMTPSA id 90AE81F01825; Wed, 28 Oct 2026 18:41:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793212888; bh=prvLrKO4GUizS34XOWHdQI0z1DqWdkfwwuHXFxOy6DM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=lgAwMXNxCBDV+kgmINHMiprY9vCoVhrRISuUuGWcAFwDDvflwDi/kzaRt4WaVPA3S GnsSabslw9mDryqklN6GewYOI0xeh0THkxYnSTzCdGQyaeaPE8cRdUeDOQwpe/PxDC GWK1S0uH6VV2SoB2ECFXgnfOobgZn3Cd2zIC9oX0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Tianchu Chen , Johannes Berg Subject: [PATCH 6.1 0313/1887] wifi: cw1200: fix TX padding OOB read leaking heap data to device Date: Wed, 28 Oct 2026 17:40:09 +0100 Message-ID: <20261028170506.351657161@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170459.200466217@linuxfoundation.org> References: <20261028170459.200466217@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tianchu Chen commit 7c1611780823b76219cb1478db53dfd890c4a9a2 upstream. The TX path rounds the transfer size up to the bus alignment (align_size(), up to 511 bytes for SDIO, 1 byte for SPI) but sends the padded length straight from the frame buffer, which has no room reserved for the padding. cw1200_data_write() therefore reads past the end of the frame and the bus transfer carries those bytes to the device. A bogus device can collect up to 511 bytes of kernel heap data per TX frame. The RX path does not have this problem: it allocates the skb with the aligned length (alloc_len) before reading. Compute the exact padding with the bus align_size() callback, make sure queued TX frames have tailroom for it, and zero the padding bytes before the transfer so nothing past the frame is exposed. This is not expected to change driver behavior on most cases: frame contents and transfer sizes are unchanged, only the content of the padding bytes (previously undefined stale memory, now zero), which the device never reads since the WSM header carries the real frame length. The skb expansion can only fail under memory exhaustion, in which case the frame is dropped like on the existing error paths of cw1200_tx(). Discovered by Atuin - Automated Vulnerability Discovery Engine. Fixes: a910e4a94f69 ("cw1200: add driver for the ST-E CW1100 & CW1200 WLAN chipsets") Cc: stable@vger.kernel.org Assisted-by: LLM Signed-off-by: Tianchu Chen Link: https://patch.msgid.link/7982b4a7e64f74e2068790ec389ca680a081f730@linux.dev Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/st/cw1200/bh.c | 8 +++++++- drivers/net/wireless/st/cw1200/txrx.c | 14 ++++++++++++++ 2 files changed, 21 insertions(+), 1 deletion(-) --- a/drivers/net/wireless/st/cw1200/bh.c +++ b/drivers/net/wireless/st/cw1200/bh.c @@ -343,6 +343,7 @@ static int cw1200_bh_tx_helper(struct cw int *tx_burst) { size_t tx_len; + size_t aligned_len; u8 *data; int ret; struct wsm_hdr *wsm; @@ -375,9 +376,14 @@ static int cw1200_bh_tx_helper(struct cw atomic_inc(&priv->bh_tx); - tx_len = priv->hwbus_ops->align_size( + aligned_len = priv->hwbus_ops->align_size( priv->hwbus_priv, tx_len); + /* Zero the bus alignment padding so no stale data is sent. */ + if (aligned_len > tx_len) + memset(data + tx_len, 0, aligned_len - tx_len); + tx_len = aligned_len; + /* Check if not exceeding CW1200 capabilities */ if (WARN_ON_ONCE(tx_len > EFFECTIVE_BUF_SIZE)) pr_debug("Write aligned len: %zu\n", tx_len); --- a/drivers/net/wireless/st/cw1200/txrx.c +++ b/drivers/net/wireless/st/cw1200/txrx.c @@ -14,6 +14,7 @@ #include "wsm.h" #include "bh.h" #include "sta.h" +#include "hwbus.h" #include "debug.h" #define CW1200_INVALID_RATE_ID (0xFF) @@ -716,6 +717,7 @@ void cw1200_tx(struct ieee80211_hw *dev, struct ieee80211_sta *sta; struct wsm_tx *wsm; bool tid_update = false; + size_t pad_len; u8 flags = 0; int ret; @@ -764,6 +766,18 @@ void cw1200_tx(struct ieee80211_hw *dev, sta = t.sta; + /* + * The bus transfer is padded up to the bus alignment and the + * padding is transferred from the frame buffer. Make sure the + * buffer has room for the padding so the device never receives + * data past the end of the frame. + */ + pad_len = priv->hwbus_ops->align_size(priv->hwbus_priv, skb->len) - + skb->len; + if (skb_tailroom(skb) < pad_len && + pskb_expand_head(skb, 0, pad_len, GFP_ATOMIC)) + goto drop; + spin_lock_bh(&priv->ps_state_lock); { tid_update = cw1200_tx_h_pm_state(priv, &t);