[PATCH bpf-next v3 2/2] bpf: Check return from set_memory_rox()

[Martin KaFai Lau]

On 3/15/24 1:55 PM, Martin KaFai Lau wrote:
> On 3/15/24 10:06 AM, Christophe Leroy wrote:
>> diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c
>> index 43356faaa057..ca1d9b87c475 100644
>> --- a/kernel/bpf/bpf_struct_ops.c
>> +++ b/kernel/bpf/bpf_struct_ops.c
>> @@ -742,8 +742,11 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map 
>> *map, void *key,
>>           if (err)
>>               goto reset_unlock;
>>       }
>> -    for (i = 0; i < st_map->image_pages_cnt; i++)
>> -        arch_protect_bpf_trampoline(st_map->image_pages[i], PAGE_SIZE);
>> +    for (i = 0; i < st_map->image_pages_cnt && !err; i++)
>> +        err = arch_protect_bpf_trampoline(st_map->image_pages[i], PAGE_SIZE);
>> +
>> +    if (err)
>> +        goto reset_unlock;
> 
> This part does not look right. The "if (err)" check should be inside the for loop.

ah. Please ignore. missed the "!err" in the for loop.