Re: [PATCH] mm: Optimizing error condition detection in do_mprotect_pkey()

From: Jarkko Sakkinen
Date: Wed Jan 20 2021 - 09:37:20 EST




On Mon, Jan 18, 2021 at 09:33:10PM +0800, Tianjia Zhang wrote:
> Obviously, the error variable detection of the if statement is
> for the mprotect callback function, so it is also put into the
> scope of calling callbck.
>
> Reported-by: Jia Zhang <zhang.jia@xxxxxxxxxxxxxxxxx>
> Signed-off-by: Tianjia Zhang <tianjia.zhang@xxxxxxxxxxxxxxxxx>

No fixes tag, no description what this commit does. Nothing
makes sense to me.

/Jarkko

> ---
> mm/mprotect.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/mm/mprotect.c b/mm/mprotect.c
> index ab709023e9aa..94188df1ee55 100644
> --- a/mm/mprotect.c
> +++ b/mm/mprotect.c
> @@ -617,10 +617,11 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
> if (tmp > end)
> tmp = end;
>
> - if (vma->vm_ops && vma->vm_ops->mprotect)
> + if (vma->vm_ops && vma->vm_ops->mprotect) {
> error = vma->vm_ops->mprotect(vma, nstart, tmp, newflags);
> - if (error)
> - goto out;
> + if (error)
> + goto out;
> + }
>
> error = mprotect_fixup(vma, &prev, nstart, tmp, newflags);
> if (error)
> --
> 2.19.1.3.ge56e4f7
>
>