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From:   Xiyu Yang <xiyuyang19@fudan.edu.cn>
To:     Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Alexios Zavras <alexios.zavras@intel.com>,
        Allison Randal <allison@lohutok.net>,
        Adit Ranadive <aditr@vmware.com>,
        Jorgen Hansen <jhansen@vmware.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Vishnu DASA <vdasa@vmware.com>,
        Xiyu Yang <xiyuyang19@fudan.edu.cn>,
        linux-kernel@vger.kernel.org
Cc:     yuanxzhang@fudan.edu.cn, kjlu@umn.edu,
        Xin Tan <tanxin.ctf@gmail.com>
Subject: [PATCH v2] VMCI: Fix NULL pointer dereference on context ptr
Date:   Mon, 23 Mar 2020 16:22:33 +0800
Message-Id: <1584951832-120773-1-git-send-email-xiyuyang19@fudan.edu.cn>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

A NULL vmci_ctx object may pass to vmci_ctx_put() from its callers.
Add a NULL check to prevent NULL pointer dereference.

Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
---
 drivers/misc/vmw_vmci/vmci_context.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/vmw_vmci/vmci_context.c b/drivers/misc/vmw_vmci/vmci_context.c
index 16695366ec92..2f4963ab51bd 100644
--- a/drivers/misc/vmw_vmci/vmci_context.c
+++ b/drivers/misc/vmw_vmci/vmci_context.c
@@ -494,7 +494,8 @@ static void ctx_free_ctx(struct kref *kref)
  */
 void vmci_ctx_put(struct vmci_ctx *context)
 {
-	kref_put(&context->kref, ctx_free_ctx);
+	if (context)
+		kref_put(&context->kref, ctx_free_ctx);
 }
 
 /*
-- 
2.7.4