linux-kernel - Re: [PATCH 1/1] mm: vmalloc: Add a scan area of VA only once

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date: Mon, 5 Feb 2024 18:20:41 +0100
From: Uladzislau Rezki <urezki@...il.com>
To: Lorenzo Stoakes <lstoakes@...il.com>
Cc: "Uladzislau Rezki (Sony)" <urezki@...il.com>, linux-mm@...ck.org,
	Andrew Morton <akpm@...ux-foundation.org>,
	LKML <linux-kernel@...r.kernel.org>, Baoquan He <bhe@...hat.com>,
	Christoph Hellwig <hch@...radead.org>,
	Matthew Wilcox <willy@...radead.org>,
	Dave Chinner <david@...morbit.com>,
	Oleksiy Avramchenko <oleksiy.avramchenko@...y.com>
Subject: Re: [PATCH 1/1] mm: vmalloc: Add a scan area of VA only once

On Sun, Feb 04, 2024 at 07:44:55PM +0000, Lorenzo Stoakes wrote:
> On Fri, Feb 02, 2024 at 08:06:28PM +0100, Uladzislau Rezki (Sony) wrote:
> > Invoke a kmemleak_scan_area() function only for newly allocated
> > objects to add a scan area within that object. There is no reason
> > to add a same scan area(pointer to beginning or inside the object)
> > several times. If a VA is obtained from the cache its scan area
> > has already been associated.
> >
> > Fixes: 7db166b4aa0d ("mm: vmalloc: offload free_vmap_area_lock lock")
> > Signed-off-by: Uladzislau Rezki (Sony) <urezki@...il.com>
> > ---
> >  mm/vmalloc.c | 12 ++++++------
> >  1 file changed, 6 insertions(+), 6 deletions(-)
> >
> > diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> > index 449f45b0e474..25a8df497255 100644
> > --- a/mm/vmalloc.c
> > +++ b/mm/vmalloc.c
> > @@ -1882,13 +1882,13 @@ static struct vmap_area *alloc_vmap_area(unsigned long size,
> >  		va = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask, node);
> >  		if (unlikely(!va))
> >  			return ERR_PTR(-ENOMEM);
> > -	}
> >
> > -	/*
> > -	 * Only scan the relevant parts containing pointers to other objects
> > -	 * to avoid false negatives.
> > -	 */
> > -	kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask);
> > +		/*
> > +		 * Only scan the relevant parts containing pointers to other objects
> > +		 * to avoid false negatives.
> > +		 */
> > +		kmemleak_scan_area(&va->rb_node, SIZE_MAX, gfp_mask);
> > +	}
> >
> >  retry:
> >  	if (addr == vend) {
> > --
> > 2.39.2
> >
> 
> Looks good to me, feel free to add:
> 
> Reviewed-by: Lorenzo Stoakes <lstoakes@...il.com>
>
Appreciate for review!

--
Uladzislau Rezki