From:   Jiasheng Jiang <jiasheng@iscas.ac.cn>
To:     ecree.xilinx@gmail.com, habetsm.xilinx@gmail.com,
        davem@davemloft.net, kuba@kernel.org
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        Jiasheng Jiang <jiasheng@iscas.ac.cn>
Subject: [PATCH] sfc_ef100: potential dereference of null pointer
Date:   Wed, 15 Dec 2021 17:41:41 +0800
Message-Id: <20211215094141.164417-1-jiasheng@iscas.ac.cn>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

The return value of kmalloc() needs to be checked.
To avoid use in efx_nic_update_stats() in case of the failure of alloc.

Fixes: b593b6f1b492 ("sfc_ef100: statistics gathering")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
 drivers/net/ethernet/sfc/ef100_nic.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/sfc/ef100_nic.c b/drivers/net/ethernet/sfc/ef100_nic.c
index 518268ce2064..ac55c6740e35 100644
--- a/drivers/net/ethernet/sfc/ef100_nic.c
+++ b/drivers/net/ethernet/sfc/ef100_nic.c
@@ -602,6 +602,9 @@ static size_t ef100_update_stats(struct efx_nic *efx,
 				 struct rtnl_link_stats64 *core_stats)
 {
 	__le64 *mc_stats = kmalloc(array_size(efx->num_mac_stats, sizeof(__le64)), GFP_ATOMIC);
+	if (!mc_stats)
+		return 0;
+
 	struct ef100_nic_data *nic_data = efx->nic_data;
 	DECLARE_BITMAP(mask, EF100_STAT_COUNT) = {};
 	u64 *stats = nic_data->stats;
-- 
2.25.1