[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20120712055655.GB3598@linux.vnet.ibm.com>
Date: Thu, 12 Jul 2012 11:26:55 +0530
From: Srikar Dronamraju <srikar@...ux.vnet.ibm.com>
To: Oleg Nesterov <oleg@...hat.com>
Cc: Joe Perches <joe@...ches.com>, Ingo Molnar <mingo@...e.hu>,
Ananth N Mavinakayanahalli <ananth@...ibm.com>,
Anton Arapov <anton@...hat.com>,
Peter Zijlstra <peterz@...radead.org>,
linux-kernel@...r.kernel.org
Subject: Re: [PATCH 3/5] uprobes: fix overflow in
vma_address/find_active_uprobe
* Oleg Nesterov <oleg@...hat.com> [2012-07-09 12:54:45]:
> On 07/08, Joe Perches wrote:
> >
> > On Sun, 2012-07-08 at 22:30 +0200, Oleg Nesterov wrote:
> > > @@ -1450,7 +1450,7 @@ static struct uprobe *find_active_uprobe(unsigned long bp_vaddr, int *is_swbp)
> > >
> > > inode = vma->vm_file->f_mapping->host;
> > > offset = bp_vaddr - vma->vm_start;
> > > - offset += (vma->vm_pgoff << PAGE_SHIFT);
> > > + offset += ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
> >
> > It's be nice to take remove the unnecessary parenthesis
> > and make it consistent with the vaddr use above it too.
>
> OK, please find v2 below.
>
> ------------------------------------------------------------------------------
> Subject: [PATCH] uprobes: fix overflow in vma_address/find_active_uprobe
>
> vma->vm_pgoff is "unsigned long", it should be promoted to loff_t
> before the multiplication to avoid the overflow.
>
> Signed-off-by: Oleg Nesterov <oleg@...hat.com>
Acked-by: Srikar Dronamraju <srikar@...ux.vnet.ibm.com>
> ---
> kernel/events/uprobes.c | 4 ++--
> 1 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
> index 47c4e24..6194edb 100644
> --- a/kernel/events/uprobes.c
> +++ b/kernel/events/uprobes.c
> @@ -117,7 +117,7 @@ static loff_t vma_address(struct vm_area_struct *vma, loff_t offset)
> loff_t vaddr;
>
> vaddr = vma->vm_start + offset;
> - vaddr -= vma->vm_pgoff << PAGE_SHIFT;
> + vaddr -= (loff_t)vma->vm_pgoff << PAGE_SHIFT;
>
> return vaddr;
> }
> @@ -1450,7 +1450,7 @@ static struct uprobe *find_active_uprobe(unsigned long bp_vaddr, int *is_swbp)
>
> inode = vma->vm_file->f_mapping->host;
> offset = bp_vaddr - vma->vm_start;
> - offset += (vma->vm_pgoff << PAGE_SHIFT);
> + offset += (loff_t)vma->vm_pgoff << PAGE_SHIFT;
> uprobe = find_uprobe(inode, offset);
> }
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists