linux-kernel - [PATCH] lib/test_meminit: optimize do_kmem_cache_rcu

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <tencent_7CB95F1C3914BCE1CA4A61FF7C20E7CCB108@qq.com>
Date:   Wed, 23 Mar 2022 11:48:24 +0800
From:   xkernel.wang@...mail.com
To:     glider@...gle.com, akpm@...ux-foundation.org
Cc:     andreyknvl@...il.com, elver@...gle.com, dvyukov@...gle.com,
        ryabinin.a.a@...il.com, kasan-dev@...glegroups.com,
        linux-mm@...ck.org, linux-kernel@...r.kernel.org,
        Xiaoke Wang <xkernel.wang@...mail.com>
Subject: [PATCH] lib/test_meminit: optimize do_kmem_cache_rcu_persistent() test

From: Xiaoke Wang <xkernel.wang@...mail.com>

To make the test more robust, there are the following changes:
1. add a check for the return value of kmem_cache_alloc().
2. properly release the object `buf` on several error paths.
3. release the objects of `used_objects` if we never hit `saved_ptr`.
4. destroy the created cache by default.

Signed-off-by: Xiaoke Wang <xkernel.wang@...mail.com>
---
 lib/test_meminit.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/lib/test_meminit.c b/lib/test_meminit.c
index 2f4c4bc..8d77c3f 100644
--- a/lib/test_meminit.c
+++ b/lib/test_meminit.c
@@ -300,13 +300,18 @@ static int __init do_kmem_cache_rcu_persistent(int size, int *total_failures)
 	c = kmem_cache_create("test_cache", size, size, SLAB_TYPESAFE_BY_RCU,
 			      NULL);
 	buf = kmem_cache_alloc(c, GFP_KERNEL);
+	if (!buf)
+		goto out;
 	saved_ptr = buf;
 	fill_with_garbage(buf, size);
 	buf_contents = kmalloc(size, GFP_KERNEL);
-	if (!buf_contents)
+	if (!buf_contents) {
+		kmem_cache_free(c, buf);
 		goto out;
+	}
 	used_objects = kmalloc_array(maxiter, sizeof(void *), GFP_KERNEL);
 	if (!used_objects) {
+		kmem_cache_free(c, buf);
 		kfree(buf_contents);
 		goto out;
 	}
@@ -327,11 +332,14 @@ static int __init do_kmem_cache_rcu_persistent(int size, int *total_failures)
 		}
 	}
 
+	for (iter = 0; iter < maxiter; iter++)
+		kmem_cache_free(c, used_objects[iter]);
+
 free_out:
-	kmem_cache_destroy(c);
 	kfree(buf_contents);
 	kfree(used_objects);
 out:
+	kmem_cache_destroy(c);
 	*total_failures += fail;
 	return 1;
 }
--