Re: [PATCH v2] Improve ptrace-error detection on Linux targets

[Sergio Durigan Junior <sergiodj@redhat.com>]

On Monday, August 26 2019, Christian Biesinger wrote:

> On Mon, Aug 26, 2019 at 1:32 PM Sergio Durigan Junior
> <sergiodj@redhat.com> wrote:
>> @@ -30,11 +32,70 @@
>>     of 0 means there are no supported features.  */
>>  static int supported_ptrace_options = -1;
>>
>> -/* Find all possible reasons we could fail to attach PID and return these
>> -   as a string.  An empty string is returned if we didn't find any reason.  */
>> +typedef int (*selinux_ftype) (const char *);
>> +
>> +/* Helper function which checks if ptrace is probably restricted
>> +   (i.e., if ERR is either EACCES or EPERM), and returns a string with
>> +   possible workarounds.  */
>> +
>> +static std::string
>> +linux_ptrace_restricted_fail_reason (int err)
>> +{
>> +  if (err != EACCES && err != EPERM)
>> +    {
>> +      /* It just makes sense to perform the checks below if errno was
>> +        either EACCES or EPERM.  */
>> +      return {};
>> +    }
>> +
>> +  std::string ret;
>> +  gdb_dlhandle_up handle = gdb_dlopen ("libselinux.so", true);
>
> I would dlopen libselinux.so.1 instead so that this works even without
> the -dev package.

Ah, right, I forgot about this.  I fixed it in my local copy, thanks for
pointing it out.

-- 
Sergio
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