From patchwork Thu Mar 21 06:41:01 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fei Shao X-Patchwork-Id: 13598429 Received: from mail-pf1-f176.google.com (mail-pf1-f176.google.com [209.85.210.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DAC854D9F2 for ; Thu, 21 Mar 2024 07:13:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.176 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711005196; cv=none; b=Kr12r4plyZpEE2E168hGynlKnyJK2SVZXUEnjM7oiFdvICeTPmm2WZU5j9H9ZgNhLH4TuZab2RbKZWeMmQlly/UtotYLJhBBQeXk7nUoi5PJPo9c/4hwqyuQYPk73xY9ayJJg+KckBUX3K/ah212PkmUaB+AuEmTl+BoCgNNe7M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711005196; c=relaxed/simple; bh=oRcLB9dQPwGzVPKTKr0KY9BPsfc919ssadAASAAgBzQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MBrAXsdc8B+H/MpSsq2VPRMP1PBOcETLdYSGyk1Ag/EiLCJS2XwHw9pj0QaZd60Dv0GDv1eQhXI1WlMm7LE6hEOmcA1T/gEwQb2J5EDeOxGNClA7IqSeUggbwbuS4j6Z9juLJ1BwhQaYUoDnYN9yGPmdHXGPKssMweahdQWHFlg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org; spf=pass smtp.mailfrom=chromium.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b=W6khe3Gc; arc=none smtp.client-ip=209.85.210.176 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chromium.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="W6khe3Gc" Received: by mail-pf1-f176.google.com with SMTP id d2e1a72fcca58-6e6082eab17so574256b3a.1 for ; Thu, 21 Mar 2024 00:13:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1711005194; x=1711609994; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=ZBiGSHa0oimyE1MM5zUN6LTK3eAVLs8v7Z76nGxN0a8=; b=W6khe3GcEEpAKtF+7aL9WtZvUgCdujfbpjF9CqdfPrmwhNDNXCNFO2abunfQeorSug vqepET/Wi/YVKHxHFZcz+3HRNH5f5V0X0lxJ2aqPyzYhe689J5iPYWnx/Ehg8vKulUuK CvwclaLtZ42oQ0vvOEXDyKEVKuUlnq27rqdFI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1711005194; x=1711609994; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=ZBiGSHa0oimyE1MM5zUN6LTK3eAVLs8v7Z76nGxN0a8=; b=JbvTZu+NDy5L6eHP1HSGo6lECIKOk4TrCfwD9JCsjhibROnjNXYYT4zOsLHXNyS1t+ 2NiENjZnMvdutaSbUZWI4D8xvxjFWo2SWrVC36hg9SIqI70cz8H6KnNMUNob5cygdMpL 0TejYKuRTiexq933I805C/Rvt2wdlV4qQMXyvjdEsRbplTIPHJtCCo6v7P4jtuofPlI+ RU8J3mmMcOOo7AP6tNKRoWIQas6ZK/7UocqqANPWmLUgvFtECnJ0L8WZ7eMQoD+AWlUG okhPGafbe5pu3G0zzqSAT0pCCjsk91e3ooy4QX61ki+1IWxApEPZ1piWNQTxW0qAqV8F tx0g== X-Forwarded-Encrypted: i=1; AJvYcCXLlFjcladRYROlFAHXZm+BfMpRxeIb8NjygjIlqunixVCzEztJcEy1WnffgOPEpLwxqwnebT20fJkygqExN6r473FBgQZvfxgS X-Gm-Message-State: AOJu0Yw88PM83ItidXgxwxmrWeA7FtQM7wRBbm+AO2zQFSY3+GtiHf6n /3KgLcjrZtE1zhm7X3m8hBLZ5XF4XAidRMGjzuDNer2Mwt0/LoyU3VxtKvqdq/NZzpR0TKIUfNl V9g== X-Google-Smtp-Source: AGHT+IEEEIHKCYtjOYJVfRhVwN68KX9lfipwtZ2TMyYDdaLt1ht07nRcowYnTodrhLwxJsrplM2RyQ== X-Received: by 2002:a05:6a21:a586:b0:1a3:6a4c:80a9 with SMTP id gd6-20020a056a21a58600b001a36a4c80a9mr11624698pzc.1.1711003409539; Wed, 20 Mar 2024 23:43:29 -0700 (PDT) Received: from fshao-p620.tpe.corp.google.com ([2401:fa00:1:10:c1ff:a4cf:ac35:8df6]) by smtp.gmail.com with ESMTPSA id lb3-20020a056a004f0300b006e664031f10sm12874938pfb.51.2024.03.20.23.43.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Mar 2024 23:43:29 -0700 (PDT) From: Fei Shao To: Mark Brown , AngeloGioacchino Del Regno Cc: Fei Shao , Daniel Kurtz , Matthias Brugger , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-spi@vger.kernel.org Subject: [PATCH 1/2] spi: spi-mt65xx: Fix NULL pointer access in interrupt handler Date: Thu, 21 Mar 2024 14:41:01 +0800 Message-ID: <20240321064313.1385316-2-fshao@chromium.org> X-Mailer: git-send-email 2.44.0.396.g6e790dbe36-goog In-Reply-To: <20240321064313.1385316-1-fshao@chromium.org> References: <20240321064313.1385316-1-fshao@chromium.org> Precedence: bulk X-Mailing-List: linux-spi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The TX buffer in spi_transfer can be a NULL pointer, so the interrupt handler may end up writing to the invalid memory and cause crashes. Add a check to xfer->tx_buf before using it. Fixes: 1ce24864bff4 ("spi: mediatek: Only do dma for 4-byte aligned buffers") Signed-off-by: Fei Shao --- drivers/spi/spi-mt65xx.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c index 8d4633b353ee..86ea822c942b 100644 --- a/drivers/spi/spi-mt65xx.c +++ b/drivers/spi/spi-mt65xx.c @@ -788,17 +788,18 @@ static irqreturn_t mtk_spi_interrupt(int irq, void *dev_id) mdata->xfer_len = min(MTK_SPI_MAX_FIFO_SIZE, len); mtk_spi_setup_packet(host); - cnt = mdata->xfer_len / 4; - iowrite32_rep(mdata->base + SPI_TX_DATA_REG, - trans->tx_buf + mdata->num_xfered, cnt); + if (trans->tx_buf) { + cnt = mdata->xfer_len / 4; + iowrite32_rep(mdata->base + SPI_TX_DATA_REG, + trans->tx_buf + mdata->num_xfered, cnt); - remainder = mdata->xfer_len % 4; - if (remainder > 0) { - reg_val = 0; - memcpy(®_val, - trans->tx_buf + (cnt * 4) + mdata->num_xfered, - remainder); - writel(reg_val, mdata->base + SPI_TX_DATA_REG); + remainder = mdata->xfer_len % 4; + if (remainder > 0) { + reg_val = 0; + memcpy(®_val, + trans->tx_buf + (cnt * 4) + mdata->num_xfered, + remainder); + writel(reg_val, mdata->base + SPI_TX_DATA_REG); } mtk_spi_enable_transfer(host);