linux-yocto-5.14: fix build with gcc-12 on host

* fixes:
  In file included from sigchain.c:3:
  In function 'xrealloc',
      inlined from 'sigchain_push.isra' at sigchain.c:26:2:
  subcmd-util.h:56:23: error: pointer may be used after 'realloc' [-Werror=use-after-free]
     56 |                 ret = realloc(ptr, size);
        |                       ^~~~~~~~~~~~~~~~~~

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>

2 files changed, 69 insertions, 1 deletions

diff --git a/meta/recipes-kernel/linux/linux-yocto/0001-libsubcmd-Fix-use-after-free-for-realloc-.-0.patch b/meta/recipes-kernel/linux/linux-yocto/0001-libsubcmd-Fix-use-after-free-for-realloc-.-0.patch
new file mode 100644
index 0000000000..2ad53f6b6e
--- /dev/null
+++ b/meta/recipes-kernel/linux/linux-yocto/0001-libsubcmd-Fix-use-after-free-for-realloc-.-0.patch
@@ -0,0 +1,66 @@
+From 52a9dab6d892763b2a8334a568bd4e2c1a6fde66 Mon Sep 17 00:00:00 2001
+From: Kees Cook <keescook@chromium.org>
+Date: Sun, 13 Feb 2022 10:24:43 -0800
+Subject: [PATCH] libsubcmd: Fix use-after-free for realloc(..., 0)
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+GCC 12 correctly reports a potential use-after-free condition in the
+xrealloc helper. Fix the warning by avoiding an implicit "free(ptr)"
+when size == 0:
+
+In file included from help.c:12:
+In function 'xrealloc',
+    inlined from 'add_cmdname' at help.c:24:2: subcmd-util.h:56:23: error: pointer may be used after 'realloc' [-Werror=use-after-free]
+   56 |                 ret = realloc(ptr, size);
+      |                       ^~~~~~~~~~~~~~~~~~
+subcmd-util.h:52:21: note: call to 'realloc' here
+   52 |         void *ret = realloc(ptr, size);
+      |                     ^~~~~~~~~~~~~~~~~~
+subcmd-util.h:58:31: error: pointer may be used after 'realloc' [-Werror=use-after-free]
+   58 |                         ret = realloc(ptr, 1);
+      |                               ^~~~~~~~~~~~~~~
+subcmd-util.h:52:21: note: call to 'realloc' here
+   52 |         void *ret = realloc(ptr, size);
+      |                     ^~~~~~~~~~~~~~~~~~
+
+Fixes: 2f4ce5ec1d447beb ("perf tools: Finalize subcmd independence")
+Reported-by: Valdis Klētnieks <valdis.kletnieks@vt.edu>
+Signed-off-by: Kees Kook <keescook@chromium.org>
+Tested-by: Valdis Klētnieks <valdis.kletnieks@vt.edu>
+Tested-by: Justin M. Forbes <jforbes@fedoraproject.org>
+Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
+Cc: linux-hardening@vger.kernel.org
+Cc: Valdis Klētnieks <valdis.kletnieks@vt.edu>
+Link: http://lore.kernel.org/lkml/20220213182443.4037039-1-keescook@chromium.org
+Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
+
+Upstream-Status: Backport [v5.17, v5.15.25]
+Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
+---
+ tools/lib/subcmd/subcmd-util.h | 11 ++---------
+ 1 file changed, 2 insertions(+), 9 deletions(-)
+
+diff --git a/tools/lib/subcmd/subcmd-util.h b/tools/lib/subcmd/subcmd-util.h
+index 794a375dad36..b2aec04fce8f 100644
+--- a/tools/lib/subcmd/subcmd-util.h
++++ b/tools/lib/subcmd/subcmd-util.h
+@@ -50,15 +50,8 @@ static NORETURN inline void die(const char *err, ...)
+ static inline void *xrealloc(void *ptr, size_t size)
+ {
+ 	void *ret = realloc(ptr, size);
+-	if (!ret && !size)
+-		ret = realloc(ptr, 1);
+-	if (!ret) {
+-		ret = realloc(ptr, size);
+-		if (!ret && !size)
+-			ret = realloc(ptr, 1);
+-		if (!ret)
+-			die("Out of memory, realloc failed");
+-	}
++	if (!ret)
++		die("Out of memory, realloc failed");
+ 	return ret;
+ }
+ 
diff --git a/meta/recipes-kernel/linux/linux-yocto_5.14.bb b/meta/recipes-kernel/linux/linux-yocto_5.14.bb
index b5be96b7c9..a48e0dbf72 100644
--- a/meta/recipes-kernel/linux/linux-yocto_5.14.bb
+++ b/meta/recipes-kernel/linux/linux-yocto_5.14.bb
@@ -39,7 +39,9 @@ KBRANCH:class-devupstream = "v5.14/base"
 # KMACHINE:qemuarm ?= "qemuarma15"
 
 SRC_URI = "git://git.yoctoproject.org/linux-yocto.git;name=machine;branch=${KBRANCH}; \
-           git://git.yoctoproject.org/yocto-kernel-cache;type=kmeta;name=meta;branch=yocto-5.14;destsuffix=${KMETA}"
+           git://git.yoctoproject.org/yocto-kernel-cache;type=kmeta;name=meta;branch=yocto-5.14;destsuffix=${KMETA} \
+           file://0001-libsubcmd-Fix-use-after-free-for-realloc-.-0.patch \
+"
 
 LIC_FILES_CHKSUM = "file://COPYING;md5=6bc538ed5bd9a7fc9398086aedcd7e46"
 LINUX_VERSION ?= "5.14.21"