From nobody Sun Feb 8 10:43:47 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 57F8AC001DE for ; Fri, 4 Aug 2023 08:15:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234465AbjHDIPb (ORCPT ); Fri, 4 Aug 2023 04:15:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53738 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234456AbjHDIP2 (ORCPT ); Fri, 4 Aug 2023 04:15:28 -0400 Received: from out30-97.freemail.mail.aliyun.com (out30-97.freemail.mail.aliyun.com [115.124.30.97]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8114E12B for ; Fri, 4 Aug 2023 01:15:27 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R451e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045170;MF=tianruidong@linux.alibaba.com;NM=1;PH=DS;RN=8;SR=0;TI=SMTPD_---0Vp.kW5O_1691136922; Received: from localhost(mailfrom:tianruidong@linux.alibaba.com fp:SMTPD_---0Vp.kW5O_1691136922) by smtp.aliyun-inc.com; Fri, 04 Aug 2023 16:15:24 +0800 From: Ruidong Tian To: linux-kernel@vger.kernel.org Cc: tianruidong@linux.alibaba.com, alexander.shishkin@linux.intel.com, coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, mike.leach@linaro.org, suzuki.poulose@arm.com, james.clark@arm.com Subject: [PATCH v3 1/1] coresight: tmc: Explicit type conversions to prevent integer overflow Date: Fri, 4 Aug 2023 16:15:14 +0800 Message-Id: <20230804081514.120171-2-tianruidong@linux.alibaba.com> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20230804081514.120171-1-tianruidong@linux.alibaba.com> References: <20230714084349.31567-1-tianruidong@linux.alibaba.com> <20230804081514.120171-1-tianruidong@linux.alibaba.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Perf cs_etm session executed unexpectedly when AUX buffer > 1G. perf record -C 0 -m ,2G -e cs_etm// -- [ perf record: Captured and wrote 2.615 MB perf.data ] Perf only collect about 2M perf data rather than 2G. This is becasuse the operation, "nr_pages << PAGE_SHIFT", in coresight tmc driver, will overflow when nr_pages >=3D 0x80000(correspond to 1G AUX buffer). The overflow cause buffer allocation to fail, and TMC driver will alloc minimal buffer size(1M). You can just get about 2M perf data(1M AUX buffer + perf data header) at least. Explicit convert nr_pages to 64 bit to avoid overflow. Fixes: 22f429f19c41 ("coresight: etm-perf: Add support for ETR backend") Signed-off-by: Ruidong Tian Reviewed-by: James Clark --- drivers/hwtracing/coresight/coresight-tmc-etf.c | 2 +- drivers/hwtracing/coresight/coresight-tmc-etr.c | 5 +++-- drivers/hwtracing/coresight/coresight-tmc.h | 2 +- 3 files changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtr= acing/coresight/coresight-tmc-etf.c index 79d8c64eac49..7406b65e2cdd 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etf.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c @@ -452,7 +452,7 @@ static int tmc_set_etf_buffer(struct coresight_device *= csdev, return -EINVAL; =20 /* wrap head around to the amount of space we have */ - head =3D handle->head & ((buf->nr_pages << PAGE_SHIFT) - 1); + head =3D handle->head & (((unsigned long)buf->nr_pages << PAGE_SHIFT) - 1= ); =20 /* find the page to write to */ buf->cur =3D head / PAGE_SIZE; diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtr= acing/coresight/coresight-tmc-etr.c index 766325de0e29..66dc5f97a009 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -45,7 +45,8 @@ struct etr_perf_buffer { }; =20 /* Convert the perf index to an offset within the ETR buffer */ -#define PERF_IDX2OFF(idx, buf) ((idx) % ((buf)->nr_pages << PAGE_SHIFT)) +#define PERF_IDX2OFF(idx, buf) \ + ((idx) % ((unsigned long)(buf)->nr_pages << PAGE_SHIFT)) =20 /* Lower limit for ETR hardware buffer */ #define TMC_ETR_PERF_MIN_BUF_SIZE SZ_1M @@ -1267,7 +1268,7 @@ alloc_etr_buf(struct tmc_drvdata *drvdata, struct per= f_event *event, * than the size requested via sysfs. */ if ((nr_pages << PAGE_SHIFT) > drvdata->size) { - etr_buf =3D tmc_alloc_etr_buf(drvdata, (nr_pages << PAGE_SHIFT), + etr_buf =3D tmc_alloc_etr_buf(drvdata, ((ssize_t)nr_pages << PAGE_SHIFT), 0, node, NULL); if (!IS_ERR(etr_buf)) goto done; diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracin= g/coresight/coresight-tmc.h index b97da39652d2..0ee48c5ba764 100644 --- a/drivers/hwtracing/coresight/coresight-tmc.h +++ b/drivers/hwtracing/coresight/coresight-tmc.h @@ -325,7 +325,7 @@ ssize_t tmc_sg_table_get_data(struct tmc_sg_table *sg_t= able, static inline unsigned long tmc_sg_table_buf_size(struct tmc_sg_table *sg_table) { - return sg_table->data_pages.nr_pages << PAGE_SHIFT; + return (unsigned long)sg_table->data_pages.nr_pages << PAGE_SHIFT; } =20 struct coresight_device *tmc_etr_get_catu_device(struct tmc_drvdata *drvda= ta); --=20 2.33.1