lkml.org 
[lkml]   [2021]   [Nov]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] kmemleak: fix kmemleak false positive report with HW tag-based kasan enable
On Fri, 19 Nov 2021 23:12:55 +0800 Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com> wrote:

> > > > Call sequence:
> > > > ptr = kmalloc(size, GFP_KERNEL);
> > > > page = virt_to_page(ptr);
> > > > kfree(page_address(page));
> > > > ptr = kmalloc(size, GFP_KERNEL);
> >
> > How is this call sequence valid? page_address returns the address of
> > the start of the page, while kmalloced object could have been located
> > in the middle of it.
>
> Thanks for pointing out. I miss the offset.
>
> It should be listed as below.
>
> ptr = kmalloc(size, GFP_KERNEL);
> page = virt_to_page(ptr);
> offset = offset_in_page(ptr);
> kfree(page_address(page) + offset);
> ptr = kmalloc(size, GFP_KERNEL);

I updated the changelog to reflect this.

\
 
 \ /
  Last update: 2021-11-19 23:44    [W:0.127 / U:0.632 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site