From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755569AbaEJStR (ORCPT ); Sat, 10 May 2014 14:49:17 -0400 Received: from mail-pa0-f48.google.com ([209.85.220.48]:47686 "EHLO mail-pa0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752029AbaEJStQ (ORCPT ); Sat, 10 May 2014 14:49:16 -0400 Date: Sun, 11 May 2014 00:19:00 +0530 From: Himangi Saraogi To: Matt Mackall , Herbert Xu , linux-kernel@vger.kernel.org Cc: julia.lawall@lip6.fr Subject: [PATCH] char: Introduce the use of the managed version of kzalloc Message-ID: <20140510184859.GA6818@himangi-Dell> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch moves data allocated using kzalloc to managed data allocated using devm_kzalloc and cleans now unnecessary kfrees in probe and remove functions. The NULL assignment to np->units is removed as there is no interaction between this field and sun4v_hvapi_unregister. Also, the labels out_free_units and out_free are removed as they are no longer required. The following Coccinelle semantic patch was used for making the change: @platform@ identifier p, probefn, removefn; @@ struct platform_driver p = { .probe = probefn, .remove = removefn, }; @prb@ identifier platform.probefn, pdev; expression e, e1, e2; @@ probefn(struct platform_device *pdev, ...) { <+... - e = kzalloc(e1, e2) + e = devm_kzalloc(&pdev->dev, e1, e2) ... ?-kfree(e); ...+> } @rem depends on prb@ identifier platform.removefn; expression e; @@ removefn(...) { <... - kfree(e); ...> } Signed-off-by: Himangi Saraogi --- I would like to know if removing the NULL assignment is OK as it may be used for security to prevent it from being read before reinitialization. drivers/char/hw_random/n2-drv.c | 24 +++++++----------------- 1 file changed, 7 insertions(+), 17 deletions(-) diff --git a/drivers/char/hw_random/n2-drv.c b/drivers/char/hw_random/n2-drv.c index 432232e..292a588 100644 --- a/drivers/char/hw_random/n2-drv.c +++ b/drivers/char/hw_random/n2-drv.c @@ -632,7 +632,7 @@ static int n2rng_probe(struct platform_device *op) multi_capable = (match->data != NULL); n2rng_driver_version(); - np = kzalloc(sizeof(*np), GFP_KERNEL); + np = devm_kzalloc(&op->dev, sizeof(*np), GFP_KERNEL); if (!np) goto out; np->op = op; @@ -653,7 +653,7 @@ static int n2rng_probe(struct platform_device *op) &np->hvapi_minor)) { dev_err(&op->dev, "Cannot register suitable " "HVAPI version.\n"); - goto out_free; + goto out; } } @@ -676,15 +676,16 @@ static int n2rng_probe(struct platform_device *op) dev_info(&op->dev, "Registered RNG HVAPI major %lu minor %lu\n", np->hvapi_major, np->hvapi_minor); - np->units = kzalloc(sizeof(struct n2rng_unit) * np->num_units, - GFP_KERNEL); + np->units = devm_kzalloc(&op->dev, + sizeof(struct n2rng_unit) * np->num_units, + GFP_KERNEL); err = -ENOMEM; if (!np->units) goto out_hvapi_unregister; err = n2rng_init_control(np); if (err) - goto out_free_units; + goto out_hvapi_unregister; dev_info(&op->dev, "Found %s RNG, units: %d\n", ((np->flags & N2RNG_FLAG_MULTI) ? @@ -697,7 +698,7 @@ static int n2rng_probe(struct platform_device *op) err = hwrng_register(&np->hwrng); if (err) - goto out_free_units; + goto out_hvapi_unregister; platform_set_drvdata(op, np); @@ -705,15 +706,9 @@ static int n2rng_probe(struct platform_device *op) return 0; -out_free_units: - kfree(np->units); - np->units = NULL; - out_hvapi_unregister: sun4v_hvapi_unregister(HV_GRP_RNG); -out_free: - kfree(np); out: return err; } @@ -730,11 +725,6 @@ static int n2rng_remove(struct platform_device *op) sun4v_hvapi_unregister(HV_GRP_RNG); - kfree(np->units); - np->units = NULL; - - kfree(np); - return 0; } -- 1.9.1