From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 93F8038910F; Tue, 21 Jul 2026 18:56:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784660167; cv=none; b=tGHXj3TQAsXuJqQEa/Bcx2LIooBcJtgjJJzFu0YHJBNgTOnWC5sFOx+k1HtXvx/eM7fRBgYzjCDrnq1beVzHOtsMje6cGzL8yPMR65t+GEMoIvmRJOtmO/fqNhEwvs8AyfiLQFQUc8g0BHRqhByn4FlmForM29Zyfvjyw4fGmfs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784660167; c=relaxed/simple; bh=/yyf4YieUYMpg3FuGCa3qEwyLIrXTpfHI/rHGxkA1O4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=O64V2vx/aSbpmOdrMfYJXx6YJSwggYFLLriXvSbB5jAA8PZRUgcK4UBnkEyJfiEk3yaMF/TZNEknk4JtpSae8axeUJY0UMXu94att/wwBK4qD0jM5w5k09ypzPtWtg74Y9/nhSd/NjXZ4/gFL4aJ5tci3P0QFyPDuB8kXH8UVLc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=EbSX8K3u; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="EbSX8K3u" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EDF861F000E9; Tue, 21 Jul 2026 18:56:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784660166; bh=qzhlldjEnZ+dkDSWoeW+gr39tocDZLTwAuEtXWVGS+M=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=EbSX8K3uy+uI0Gy9+D6wJh36Jrf5XuhO7crys9ct8rlcZstNMel2397fxT02vCpL9 eTXFeWyjRhfplGDV301UMK/24nmhaMx07TdMtfiMj9fLO4q72d/l4fOFoZkxQG7kj1 z+lf3jN3ZqXI2ueH/AL9nrYW5x7ppS7bXgOGtIkg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dan Carpenter , Alexandru Hossu , Sasha Levin Subject: [PATCH 7.1 0834/2077] staging: nvec: fix use-after-free in nvec_rx_completed() Date: Tue, 21 Jul 2026 17:08:27 +0200 Message-ID: <20260721152612.460031648@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152552.646164743@linuxfoundation.org> References: <20260721152552.646164743@linuxfoundation.org> User-Agent: quilt/0.69 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-Transfer-Encoding: 8bit 7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexandru Hossu [ Upstream commit 26813881181deb3a32fbb59eadb2599cbe8423f6 ] In nvec_rx_completed(), when an incomplete RX transfer is detected, nvec_msg_free() is called to return the message back to the pool by clearing its 'used' atomic flag. Immediately after this, the code accesses nvec->rx->data[0] to check the message type. Since nvec_msg_free() marks the pool slot as available via atomic_set(), any concurrent or subsequent call to nvec_msg_alloc() could claim that same slot and overwrite its data[] array. Reading nvec->rx->data[0] after freeing the message is therefore a use-after-free. Fix this by saving the message type byte before calling nvec_msg_free(), then using the saved value for the battery quirk check. Fixes: d6bdcf2e1019 ("staging: nvec: Add battery quirk to ignore incomplete responses") Reviewed-by: Dan Carpenter Signed-off-by: Alexandru Hossu Link: https://patch.msgid.link/20260427081713.3401874-2-hossu.alexandru@gmail.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/staging/nvec/nvec.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/staging/nvec/nvec.c b/drivers/staging/nvec/nvec.c index 952c5a849a563d..2a3499dd4d6342 100644 --- a/drivers/staging/nvec/nvec.c +++ b/drivers/staging/nvec/nvec.c @@ -494,6 +494,8 @@ static void nvec_tx_completed(struct nvec_chip *nvec) static void nvec_rx_completed(struct nvec_chip *nvec) { if (nvec->rx->pos != nvec_msg_size(nvec->rx)) { + unsigned char msg_type = nvec->rx->data[0]; + dev_err(nvec->dev, "RX incomplete: Expected %u bytes, got %u\n", (uint)nvec_msg_size(nvec->rx), (uint)nvec->rx->pos); @@ -502,7 +504,7 @@ static void nvec_rx_completed(struct nvec_chip *nvec) nvec->state = 0; /* Battery quirk - Often incomplete, and likes to crash */ - if (nvec->rx->data[0] == NVEC_BAT) + if (msg_type == NVEC_BAT) complete(&nvec->ec_transfer); return; -- 2.53.0