+ cgroup-fix-an-error-handling-path-in-alloc_pagecache_max_30m.patch added to mm-unstable branch

+ cgroup-fix-an-error-handling-path-in-alloc_pagecache_max_30m.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: cgroup: fix an error handling path in alloc_pagecache_max_30M()
has been added to the -mm mm-unstable branch.  Its filename is
     cgroup-fix-an-error-handling-path-in-alloc_pagecache_max_30m.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/cgroup-fix-an-error-handling-path-in-alloc_pagecache_max_30m.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Subject: cgroup: fix an error handling path in alloc_pagecache_max_30M()
Date: Sun, 22 May 2022 16:18:51 +0200

If the first goto is taken, 'fd' is not opened yet (and is un-initialized).
So a direct return is safer.

Link: https://lkml.kernel.org/r/628312312eb40e0e39463a2c06415fde5295c716.1653229120.git.christophe.jaillet@wanadoo.fr
Fixes: c1a31a2f7a9c ("cgroup: fix racy check in alloc_pagecache_max_30M() helper function")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zefan Li <lizefan.x@bytedance.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: David Vernet <void@manifault.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 tools/testing/selftests/cgroup/test_memcontrol.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/tools/testing/selftests/cgroup/test_memcontrol.c~cgroup-fix-an-error-handling-path-in-alloc_pagecache_max_30m
+++ a/tools/testing/selftests/cgroup/test_memcontrol.c
@@ -574,7 +574,7 @@ static int alloc_pagecache_max_30M(const
 	high = cg_read_long(cgroup, "memory.high");
 	max = cg_read_long(cgroup, "memory.max");
 	if (high != MB(30) && max != MB(30))
-		goto cleanup;
+		return -1;
 
 	fd = get_temp_fd();
 	if (fd < 0)
_

Patches currently in -mm which might be from christophe.jaillet@wanadoo.fr are

cgroup-fix-an-error-handling-path-in-alloc_pagecache_max_30m.patch