Re: [PATCH bpf-next v2 1/4] selftests/bpf: Add some null pointer checks

[Kunwu Chan <kunwu.chan@linux.dev>]

On 2024/5/10 19:20, Muhammad Usama Anjum wrote:
> On 5/10/24 2:58 PM, kunwu.chan@linux.dev wrote:
>> From: Kunwu Chan <chentao@kylinos.cn>
>>
>> There is a 'malloc' call, which can be unsuccessful.
>> This patch will add the malloc failure checking
>> to avoid possible null dereference.
>>
>> Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
>> ---
>>   tools/testing/selftests/bpf/test_progs.c | 7 +++++++
>>   1 file changed, 7 insertions(+)
>>
>> diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
>> index 89ff704e9dad..ecc3ddeceeeb 100644
>> --- a/tools/testing/selftests/bpf/test_progs.c
>> +++ b/tools/testing/selftests/bpf/test_progs.c
>> @@ -582,6 +582,11 @@ int compare_stack_ips(int smap_fd, int amap_fd, int stack_trace_len)
>>   
>>   	val_buf1 = malloc(stack_trace_len);
>>   	val_buf2 = malloc(stack_trace_len);
>> +	if (!val_buf1 || !val_buf2) {
>> +		err = -ENOMEM;
> Return from here instead of going to out where free(val_buf*) is being called.
I think it's no harm.  And Unify the processing at the end to achieve 
uniform format.
>> +		goto out;
>> +	}
>> +
>>   	cur_key_p = NULL;
>>   	next_key_p = &key;
>>   	while (bpf_map_get_next_key(smap_fd, cur_key_p, next_key_p) == 0) {
>> @@ -1197,6 +1202,8 @@ static int dispatch_thread_send_subtests(int sock_fd, struct test_state *state)
>>   	int subtest_num = state->subtest_num;
>>   
>>   	state->subtest_states = malloc(subtest_num * sizeof(*subtest_state));
>> +	if (!state->subtest_states)
>> +		return -ENOMEM;
>>   
>>   	for (int i = 0; i < subtest_num; i++) {
>>   		subtest_state = &state->subtest_states[i];

-- 
Thanks,
   Kunwu.Chan