Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752175AbaF1Isw (ORCPT ); Sat, 28 Jun 2014 04:48:52 -0400 Received: from mailrelay005.isp.belgacom.be ([195.238.6.171]:29255 "EHLO mailrelay005.isp.belgacom.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751237AbaF1Isu (ORCPT ); Sat, 28 Jun 2014 04:48:50 -0400 X-Belgacom-Dynamic: yes X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AkUHAB6ArlNbsk2v/2dsb2JhbABagw2regUBAQEBAQEFAW0BmQKBCBd1hGAjgRo3iEYBxHgXhWSJIR2ELQWPeopjk3uDRDs From: Fabian Frederick To: linux-kernel@vger.kernel.org Cc: Fabian Frederick , Julia Lawall , Gilles Muller , Joe Perches , Andrew Morton Subject: [PATCH V3] scripts/coccinelle/free: add NULL test before freeing functions Date: Sat, 28 Jun 2014 10:47:27 +0200 Message-Id: <1403945247-21549-1-git-send-email-fabf@skynet.be> X-Mailer: git-send-email 1.8.4.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Warns or generates patch for NULL check before the following functions: kfree usb_free_urb debugfs_remove debugfs_remove_recursive Cc: Julia Lawall Cc: Gilles Muller Cc: Joe Perches Cc: Andrew Morton Signed-off-by: Fabian Frederick --- V3: -Update print_main message. -Add patch mode (suggested by Julia Lawall) V2: -Add 3 more functions to kfree (suggested by Joe Perches) -Update warning message to involve code analysis (suggested by Julia Lawall) scripts/coccinelle/free/ifnullfree.cocci | 53 ++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) create mode 100644 scripts/coccinelle/free/ifnullfree.cocci diff --git a/scripts/coccinelle/free/ifnullfree.cocci b/scripts/coccinelle/free/ifnullfree.cocci new file mode 100644 index 0000000..c826d98 --- /dev/null +++ b/scripts/coccinelle/free/ifnullfree.cocci @@ -0,0 +1,53 @@ +/// NULL check before some freeing functions is not needed. +/// +/// Based on checkpatch warning +/// "kfree(NULL) is safe this check is probably not required" +/// and kfreeaddr.cocci by Julia Lawall. +/// +/// Comments: - +/// Options: --no-includes --include-headers + +virtual patch +virtual org +virtual report +virtual context + +@r2 depends on patch@ +expression E; +@@ +- if (E) +( +- kfree(E); ++ kfree(E); +| +- debugfs_remove(E); ++ debugfs_remove(E); +| +- debugfs_remove_recursive(E); ++ debugfs_remove_recursive(E); +| +- usb_free_urb(E); ++ usb_free_urb(E); +) + +@r depends on context || report || org @ +expression E; +position p; +@@ + +* if (E) +* \(kfree@p\|debugfs_remove@p\|debugfs_remove_recursive@p\|usb_free_urb\)(E); + +@script:python depends on org@ +p << r.p; +@@ + +cocci.print_main("NULL check before that freeing function is not needed", p) + +@script:python depends on report@ +p << r.p; +@@ + +msg = "WARNING: NULL check before freeing functions like kfree, debugfs_remove, debugfs_remove_recursive or usb_free_urb is not needed. Maybe consider reorganizing relevant code to avoid passing NULL values." +coccilib.report.print_report(p[0], msg) + -- 1.8.4.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/