Re: [PATCH v2 1/5] exec: Only compute current once in flush_old_exec

Bernd Edlinger
2020-03-09T19:27:12Z

On 3/9/20 6:56 PM, Bernd Edlinger wrote:
> On 3/9/20 6:34 PM, Eric W. Biederman wrote:
>> Bernd Edlinger <bernd.edlinger@hotmail.de> writes:
>>
>>> On 3/8/20 10:35 PM, Eric W. Biederman wrote:
>>>>
>>>> Make it clear that current only needs to be computed once in
>>>> flush_old_exec. This may have some efficiency improvements and it
>>>> makes the code easier to change.
>>>>
>>>> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
>>>> ---
>>>> fs/exec.c | 9 +++++----
>>>> 1 file changed, 5 insertions(+), 4 deletions(-)
>>>>
>>>> diff --git a/fs/exec.c b/fs/exec.c
>>>> index db17be51b112..c3f34791f2f0 100644
>>>> --- a/fs/exec.c
>>>> +++ b/fs/exec.c
>>>> @@ -1260,13 +1260,14 @@ void __set_task_comm(struct task_struct *tsk, const char *buf, bool exec)
>>>> */
>>>> int flush_old_exec(struct linux_binprm * bprm)
>>>> {
>>>> + struct task_struct *me = current;
>>>> int retval;
>>>>
>>>> /*
>>>> * Make sure we have a private signal table and that
>>>> * we are unassociated from the previous thread group.
>>>> */
>>>> - retval = de_thread(current);
>>>> + retval = de_thread(me);
>>>> if (retval)
>>>> goto out;
>>>>
>>>> @@ -1294,10 +1295,10 @@ int flush_old_exec(struct linux_binprm * bprm)
>>>> bprm->mm = NULL;
>>>>
>>>> set_fs(USER_DS);
>>>> - current->flags &= ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD |
>>>> + me->flags &= ~(PF_RANDOMIZE | PF_FORKNOEXEC | PF_KTHREAD |
>>>> PF_NOFREEZE | PF_NO_SETAFFINITY);
>>>
>>> I wonder if this line should be aligned with the previous?
>>
>> In this case I don't think so. The style used for second line is indent
>> with tabs as much as possible to the right. I haven't changed that.
>>
>> Further mixing a change in indentation style with just a variable rename
>> will make the patch confusing to read because two things have to be
>> verified at the same time.
>>
>> So while I see why you ask I think this bit needs to stay as is.
>>
>
> Ah, okay, I see.
> Thanks for explaining this rule, I was not aware of it,
> but I am still new here :)
>

Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>

Bernd.