sfc_ef100: potential dereference of null pointer

[ Upstream commit 407ecd1bd726f240123f704620d46e285ff30dd9 ]

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>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ethernet/sfc/ef100_nic.c b/drivers/net/ethernet/sfc/ef100_nic.c
index 3148fe7703564561fd5d29fcd44f04ba3b8a4373..cb6897c2193c23ca9f423df50e6f224b03d3c2b3 100644 (file)
--- a/drivers/net/ethernet/sfc/ef100_nic.c
+++ b/drivers/net/ethernet/sfc/ef100_nic.c
@@ -597,6 +597,9 @@ static size_t ef100_update_stats(struct efx_nic *efx,
        ef100_common_stat_mask(mask);
        ef100_ethtool_stat_mask(mask);
 
+       if (!mc_stats)
+               return 0;
+
        efx_nic_copy_stats(efx, mc_stats);
        efx_nic_update_stats(ef100_stat_desc, EF100_STAT_COUNT, mask,
                             stats, mc_stats, false);