From c11f0d88ba462976335a4990a30a99d1d0b49195 Mon Sep 17 00:00:00 2001 From: Heinrich Schuchardt Date: Sun, 19 Apr 2020 11:56:02 +0200 Subject: [PATCH] coccinelle: adjust NULL check before free() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The free() function checks if its argument is NULL. We should avoid checking for NULL before calling free like in     if (result->tds)         free(result->tds); The list of relevant functions differs between Linux and U-Boot, e.g. we use free(). Adjust the list of relevant functions. Signed-off-by: Heinrich Schuchardt --- scripts/coccinelle/free/ifnullfree.cocci | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) diff --git a/scripts/coccinelle/free/ifnullfree.cocci b/scripts/coccinelle/free/ifnullfree.cocci index 14a4cd98e8..2d59545d7d 100644 --- a/scripts/coccinelle/free/ifnullfree.cocci +++ b/scripts/coccinelle/free/ifnullfree.cocci @@ -1,10 +1,11 @@ +// SPDX-License-Identifier: GPL-2.0-only /// 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. /// -// Copyright: (C) 2014 Fabian Frederick. GPLv2. +// Copyright: (C) 2014 Fabian Frederick. // Comments: - // Options: --no-includes --include-headers @@ -18,21 +19,19 @@ expression E; @@ - if (E != NULL) ( - kfree(E); + free(E); | - kzfree(E); + kfree(E); | - debugfs_remove(E); + vfree(E); | - debugfs_remove_recursive(E); + vfree_recursive(E); | - usb_free_urb(E); + kmem_cache_free(E); | kmem_cache_destroy(E); | - mempool_destroy(E); -| - dma_pool_destroy(E); + gzfree(E); ) @r depends on context || report || org @ @@ -41,9 +40,8 @@ position p; @@ * if (E != NULL) -* \(kfree@p\|kzfree@p\|debugfs_remove@p\|debugfs_remove_recursive@p\| -* usb_free_urb@p\|kmem_cache_destroy@p\|mempool_destroy@p\| -* dma_pool_destroy@p\)(E); +* \(free@p\|kfree@p\|vfree@p\|debugfs_remove_recursive@p\| +* kmem_cache_free@p\|kmem_cache_destroy@p\|gzfree@p\)(E); @script:python depends on org@ p << r.p; @@ -55,5 +53,5 @@ cocci.print_main("NULL check before that freeing function is not needed", p) 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." +msg = "WARNING: NULL check before some freeing functions is not needed." coccilib.report.print_report(p[0], msg) -- 2.39.5