Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   GUO Zihua <guozihua@huawei.com>
To:     <linux-integrity@vger.kernel.org>
CC:     <wangweiyang2@huawei.com>, <xiujianfeng@huawei.com>,
        <weiyongjun1@huawei.com>, <peterhuewe@gmx.de>, <jarkko@kernel.org>,
        <jgg@ziepe.ca>, <linux-kernel@vger.kernel.org>
Subject: [PATCH] tpm: Fix memory leak in tpmm_chip_alloc
Date:   Mon, 7 Mar 2022 18:48:27 +0800
Message-ID: <20220307104827.40843-1-guozihua@huawei.com>
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

Fix a memory leak in tpmm_chip_alloc. devm_add_action_or_reset would
call put_device on error, while tpm->devs is left untouched. Call
put_device on tpm->devs as well if devm_add_action_or_reset returns an
error.

Fixes: fdc915f7f719 ("tpm: expose spaces via a device link /dev/tpmrm")
Signed-off-by: GUO Zihua <guozihua@huawei.com>
---
 drivers/char/tpm/tpm-chip.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index b009e7479b70..0a92334e8c40 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -308,6 +308,12 @@ static int tpm_class_shutdown(struct device *dev)
 	return 0;
 }
 
+static void tpm_chip_free(struct tpm_chip *chip)
+{
+	put_device(&chip->devs);
+	put_device(&chip->dev);
+}
+
 /**
  * tpm_chip_alloc() - allocate a new struct tpm_chip instance
  * @pdev: device to which the chip is associated
@@ -396,8 +402,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
 	return chip;
 
 out:
-	put_device(&chip->devs);
-	put_device(&chip->dev);
+	tpm_chip_free(chip);
 	return ERR_PTR(rc);
 }
 EXPORT_SYMBOL_GPL(tpm_chip_alloc);
@@ -420,8 +425,8 @@ struct tpm_chip *tpmm_chip_alloc(struct device *pdev,
 		return chip;
 
 	rc = devm_add_action_or_reset(pdev,
-				      (void (*)(void *)) put_device,
-				      &chip->dev);
+				      (void (*)(void *)) tpm_chip_free,
+				      chip);
 	if (rc)
 		return ERR_PTR(rc);
 
-- 
2.17.1