From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) (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 0164C277011; Wed, 11 Jun 2025 13:16:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.176.79.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749647812; cv=none; b=HS4RFzfuriUMjnxJvEhHcsZPBuj1xLhqDg7KxLiGei7ARCCtdtNYzqTcIPlmZlcZ6lEBA5azDkKekcVI25cNJk/3DnQRBwf/4eYRl+1L7jEFhXoSCcNgpWYIo7dI6WRAQvudXZpK3Iy+dTIQWTFWCF9jgIE/UM8OwUPNylkVkbA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749647812; c=relaxed/simple; bh=mOA2uHhLVAJnM0AAacilOeTj2Muvi2Yo8XU4SD/q028=; h=Date:From:To:CC:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=hkugqz7QqoSv1wbpnRdCVB6tSiQ7jD/b5lL5kduCcripfM4IuQmVd0o2qMQ2OtACH+ioQNMJvawm6ziyqsBJ1Lr2c0KZb5b5KqNWSLHu23fo1XEJwXNBKp7ABFiLcufnP/RpVT0vRKD4/xugYpPXQp0kbh5eYNcnnvnfqU043VE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=185.176.79.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.18.186.31]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4bHR2t0p0Wz6JB2J; Wed, 11 Jun 2025 21:14:46 +0800 (CST) Received: from frapeml500008.china.huawei.com (unknown [7.182.85.71]) by mail.maildlp.com (Postfix) with ESMTPS id BAD2C1402F4; Wed, 11 Jun 2025 21:16:38 +0800 (CST) Received: from localhost (10.203.177.66) by frapeml500008.china.huawei.com (7.182.85.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Wed, 11 Jun 2025 15:16:38 +0200 Date: Wed, 11 Jun 2025 14:16:37 +0100 From: Jonathan Cameron To: Li Ming CC: , , , , , , , , Subject: Re: [PATCH 1/1] cxl/edac: Fix potential memory leak issues Message-ID: <20250611141637.0000546b@huawei.com> In-Reply-To: <20250611033542.96184-1-ming.li@zohomail.com> References: <20250611033542.96184-1-ming.li@zohomail.com> X-Mailer: Claws Mail 4.3.0 (GTK 3.24.42; x86_64-w64-mingw32) Precedence: bulk X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: lhrpeml500010.china.huawei.com (7.191.174.240) To frapeml500008.china.huawei.com (7.182.85.71) On Wed, 11 Jun 2025 11:35:42 +0800 Li Ming wrote: > In cxl_store_rec_gen_media() and cxl_store_rec_dram(), use kmemdup() to > duplicate a cxl gen_media/dram event to store the event in a xarray by > xa_store(). The cxl gen_media/dram event allocated by kmemdup() should > be freed in the case that the xa_store() fails. > > Fixes: 0b5ccb0de1e2 ("cxl/edac: Support for finding memory operation attributes from the current boot") > Signed-off-by: Li Ming Good fine but I'm not sure this is the best fix. > --- > base-commit: 87b42c114cdda76c8ad3002f2096699ad5146cb3 cxl/fixes > --- > drivers/cxl/core/edac.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/drivers/cxl/core/edac.c b/drivers/cxl/core/edac.c > index 2cbc664e5d62..b4c5c23a45d4 100644 > --- a/drivers/cxl/core/edac.c > +++ b/drivers/cxl/core/edac.c > @@ -1086,13 +1086,13 @@ static void cxl_del_overflow_old_recs(struct xarray *rec_xarray) > int cxl_store_rec_gen_media(struct cxl_memdev *cxlmd, union cxl_event *evt) > { > struct cxl_mem_err_rec *array_rec = cxlmd->err_rec_array; > - struct cxl_event_gen_media *rec; > void *old_rec; > > if (!IS_ENABLED(CONFIG_CXL_EDAC_MEM_REPAIR) || !array_rec) > return 0; > > - rec = kmemdup(&evt->gen_media, sizeof(*rec), GFP_KERNEL); > + struct cxl_event_gen_media *rec __free(kfree) = > + kmemdup(&evt->gen_media, sizeof(*rec), GFP_KERNEL); > if (!rec) > return -ENOMEM; > > @@ -1106,6 +1106,7 @@ int cxl_store_rec_gen_media(struct cxl_memdev *cxlmd, union cxl_event *evt) > > cxl_del_expired_gmedia_recs(&array_rec->rec_gen_media, rec); > cxl_del_overflow_old_recs(&array_rec->rec_gen_media); > + retain_and_null_ptr(rec); > > return 0; > } > @@ -1114,13 +1115,13 @@ EXPORT_SYMBOL_NS_GPL(cxl_store_rec_gen_media, "CXL"); > int cxl_store_rec_dram(struct cxl_memdev *cxlmd, union cxl_event *evt) > { > struct cxl_mem_err_rec *array_rec = cxlmd->err_rec_array; > - struct cxl_event_dram *rec; > void *old_rec; > > if (!IS_ENABLED(CONFIG_CXL_EDAC_MEM_REPAIR) || !array_rec) > return 0; > > - rec = kmemdup(&evt->dram, sizeof(*rec), GFP_KERNEL); > + struct cxl_event_dram *rec __free(kfree) = > + kmemdup(&evt->dram, sizeof(*rec), GFP_KERNEL); > if (!rec) > return -ENOMEM; > > @@ -1134,6 +1135,7 @@ int cxl_store_rec_dram(struct cxl_memdev *cxlmd, union cxl_event *evt) > > cxl_del_expired_dram_recs(&array_rec->rec_dram, rec); > cxl_del_overflow_old_recs(&array_rec->rec_dram); > + retain_and_null_ptr(rec); I'd move this up to immediately after we hand it over to the xa successfully. Actually I'm not sure this is a good use of __free given we have a single error path to handle it in and have to manually release it in a different call to where it is passed to the xa_store() function. Maybe better to just kfree in the error path. > > return 0; > }