Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Ivan Bornyakov <brnkv.i1@gmail.com>
To:     devel@driverdev.osuosl.org
Cc:     linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org,
        benchan@chromium.org, jnjoseph@google.com, rspringer@google.com,
        Ivan Bornyakov <brnkv.i1@gmail.com>
Subject: [PATCH] staging: gasket: sysfs: fix potential null dereference
Date:   Tue, 31 Jul 2018 18:23:20 +0300
Message-Id: <20180731152320.11575-1-brnkv.i1@gmail.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Add handling of possible allocation failure.

Reported by smatch:

  drivers/staging/gasket/gasket_sysfs.c:105 put_mapping() error: potential null dereference 'files_to_remove'. (kcalloc returns null)

Signed-off-by: Ivan Bornyakov <brnkv.i1@gmail.com>
---
 drivers/staging/gasket/gasket_sysfs.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/staging/gasket/gasket_sysfs.c b/drivers/staging/gasket/gasket_sysfs.c
index ef4eca02afa6..682e5c21f203 100644
--- a/drivers/staging/gasket/gasket_sysfs.c
+++ b/drivers/staging/gasket/gasket_sysfs.c
@@ -101,6 +101,12 @@ static void put_mapping(struct gasket_sysfs_mapping *mapping)
 		files_to_remove = kcalloc(num_files_to_remove,
 					  sizeof(*files_to_remove),
 					  GFP_KERNEL);
+		if (!files_to_remove) {
+			pr_err("%s: can't allocate memory\n", __func__);
+			mutex_unlock(&mapping->mutex);
+			return;
+		}
+
 		for (i = 0; i < num_files_to_remove; i++)
 			files_to_remove[i] = mapping->attributes[i].attr;
 
-- 
2.16.4