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

From: Eric W. Biederman
Date: Mon Mar 09 2020 - 13:36:49 EST


Bernd Edlinger <bernd.edlinger@xxxxxxxxxx> 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@xxxxxxxxxxxx>
>> ---
>> 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.

Eric