RE: [RFC][PATCH 04/15] Fix crash in tstatus after detach

["Wallin, Henrik" <Henrik dot Wallin at windriver dot com>]

2015-10-15 19:22 GMT+02:00 Pedro Alves <palves@redhat.com>:
> On 10/14/2015 12:14 PM, henrik.wallin@windriver.com wrote:
>> From: Par Olsson <par.olsson@windriver.com>
>>
>> When calling tstatus after detaching the process,
>> gdbserver tries to access inferior memory which
>> results in a crash.
>> This changes the behavior of the agent_loaded_p()
>> to return false if no inferior is loaded.
>
> Sounds like it should be easy to cook up a testcase.
> Could you do that?

I will do, after I manage to actually reproduce this one...
The patch was done on 7.6 and then rebased. I will check some more but it looks like this might've been fixed by some other changes between 7.6 and master.

>
>>
>> gdb/ChangeLog:
>>
>>       * agent.c (agent_loaded_p): Add check that inferior is present.
>>
>> Signed-off-by: Par Olsson <par.olsson@windriver.com>
>> Signed-off-by: Henrik Wallin <henrik.wallin@windriver.com>
>> ---
>>  gdb/common/agent.c | 7 +++++++
>>  1 file changed, 7 insertions(+)
>>
>> diff --git a/gdb/common/agent.c b/gdb/common/agent.c
>> index 5c307290589d..c9b6c41bc4ff 100644
>> --- a/gdb/common/agent.c
>> +++ b/gdb/common/agent.c
>> @@ -73,9 +73,16 @@ static struct ipa_sym_addresses ipa_sym_addrs;
>>
>>  static int all_agent_symbols_looked_up = 0;
>>
>> +#ifdef GDBSERVER
>> +#include <inferiors.h>
>> +#endif
>>  int
>>  agent_loaded_p (void)
>>  {
>> +#ifdef GDBSERVER
>> +  if (current_thread == NULL)
>> +    return 0;
>> +#endif
>>    return all_agent_symbols_looked_up;
>>  }
>>
>
> Should probably be moved up to the caller.

I will check that.

thanks,
/ Henrik