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 7199746D0B2; Tue, 21 Jul 2026 18:02:22 +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=1784656943; cv=none; b=FRLU6vVBkWm/vL9cAlL1b7zzzjHPU6QeAiyeY8jEhbod/7Mdcid6BYhke2LN9d8S6ub8ZbJBw0L7w4yHJYffyBcTz+8UFZZc+mT33jqeKiXA1FgenpGFDktnkNeNI/3m2ZMlzDGC9XlL/9VXe5bebkk2dMpGXXdgnLWJjTA9rvY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784656943; c=relaxed/simple; bh=JqHPqxyfH1Ajg1cbc9X1Rh7d25+ySiExzXze5lSsgDg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hTsUPCIEe030VVJ349QGivordmD1ZL+PICX/u9QCHyzhNUtefLDXULM6s7BrTGTxXH9ma44+2t8PjEl/8Y2qTpwkHxf6oRWeLBoFKgmWlwDXD34qCgf1yZy1ed/7bA71ZR/pC8HdvqKmFokv6D4VcT1n1zdo/xTJq4239cs/83w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=QAP2QmWK; 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="QAP2QmWK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 993EF1F000E9; Tue, 21 Jul 2026 18:02:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784656942; bh=vb/LQ7rPvMHD1aFN6P9G/sbStPh5sIhi5+gJBfBBCho=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=QAP2QmWKzSTFT/IifD1tTT6OUf/+CQB1NOkxyJqhu+dYp1OPGVsge39XPUMdhYwzz NY1MJJQaKzkhXyBv8hk/QJSadTKuzNvvm3laNrtMgae2cRjWU3d/zSlX4SoleIRCzw ycdCJOQms2vvrqs3+D37p9UUAulcbjYyvQQwi1lo= 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 6.18 0577/1611] staging: nvec: fix use-after-free in nvec_rx_completed() Date: Tue, 21 Jul 2026 17:11:33 +0200 Message-ID: <20260721152528.355860467@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152514.750365251@linuxfoundation.org> References: <20260721152514.750365251@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 6.18-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 263774e6a78cae..1cdaf7dd02e9f1 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