From:   Bernard Zhao <bernard@vivo.com>
To:     Paul Moore <paul@paul-moore.com>,
        Stephen Smalley <stephen.smalley.work@gmail.com>,
        Eric Paris <eparis@parisplace.org>, selinux@vger.kernel.org,
        linux-kernel@vger.kernel.org
Cc:     Bernard Zhao <bernard@vivo.com>
Subject: [PATCH] security/selinux: fix potential memleak
Date:   Wed,  1 Dec 2021 19:34:46 -0800
Message-Id: <20211202033447.253596-1-bernard@vivo.com>
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This patch try to fix potential memleak in function
selinux_fs_context_dup`s error branch.

Signed-off-by: Bernard Zhao <bernard@vivo.com>
---
 security/selinux/hooks.c | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 62d30c0a30c2..36d7fc373839 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2856,24 +2856,38 @@ static int selinux_fs_context_dup(struct fs_context *fc,
 	if (src->fscontext) {
 		opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL);
 		if (!opts->fscontext)
-			return -ENOMEM;
+			goto err_fscontext;
 	}
 	if (src->context) {
 		opts->context = kstrdup(src->context, GFP_KERNEL);
 		if (!opts->context)
-			return -ENOMEM;
+			goto err_context;
 	}
 	if (src->rootcontext) {
 		opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL);
 		if (!opts->rootcontext)
-			return -ENOMEM;
+			goto err_rootcontext;
 	}
 	if (src->defcontext) {
 		opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL);
 		if (!opts->defcontext)
-			return -ENOMEM;
+			goto err_defcontext;
 	}
 	return 0;
+
+err_defcontext:
+	if (src->rootcontext)
+		kfree(opts->rootcontext);
+err_rootcontext:
+	if (src->context)
+		kfree(opts->context);
+err_context:
+	if (src->fscontext)
+		kfree(opts->fscontext);
+err_fscontext:
+	kfree(fc->security);
+
+	return -ENOMEM;
 }
 
 static const struct fs_parameter_spec selinux_fs_parameters[] = {
-- 
2.33.1