On Fri, Mar 11, 2022 at 02:43:48PM +0800, Greg KH wrote:
>> As the potential failure of the kvmalloc_array(),
>> it should be better to check and restore the 'data'
>> if fails in order to avoid the dereference of the
>> NULL pointer.
>>
>> Fixes: 6ae746711263 ("hv_netvsc: Add per-cpu ethtool stats for netvsc")
>> Signed-off-by: Jiasheng Jiang <jiasheng@xxxxxxxxxxx>
>> ---
>> drivers/net/hyperv/netvsc_drv.c | 6 ++++++
>> 1 file changed, 6 insertions(+)
>>
>> diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
>> index 3646469433b1..018c4a5f6f44 100644
>> --- a/drivers/net/hyperv/netvsc_drv.c
>> +++ b/drivers/net/hyperv/netvsc_drv.c
>> @@ -1587,6 +1587,12 @@ static void netvsc_get_ethtool_stats(struct net_device *dev,
>> pcpu_sum = kvmalloc_array(num_possible_cpus(),
>> sizeof(struct netvsc_ethtool_pcpu_stats),
>> GFP_KERNEL);
>> + if (!pcpu_sum) {
>> + for (j = 0; j < i; j++)
>> + data[j] = 0;
>> + return;
>> + }
>
>How did you test this to verify it is correct?
Thanks, I have tested the patch by kernel_patch_verify,
and all the tests are passed.
Jiang
