[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <20110509210754.GN2268@decadent.org.uk>
Date: Mon, 9 May 2011 22:07:54 +0100
From: Ben Hutchings <ben@...adent.org.uk>
To: Jesper Juhl <jj@...osbits.net>
Cc: Dan Rosenberg <drosenberg@...curity.com>,
Russell King <rmk+kernel@....linux.org.uk>,
Greg KH <gregkh@...e.de>, linux-kernel@...r.kernel.org,
stable@...nel.org, akpm@...ux-foundation.org,
torvalds@...ux-foundation.org, stable-review@...nel.org,
alan@...rguk.ukuu.org.uk
Subject: Re: [Stable-review] [patch 31/38] ARM: 6891/1: prevent heap
corruption in OABI semtimedop
On Mon, May 09, 2011 at 10:09:19PM +0200, Jesper Juhl wrote:
> On Sat, 7 May 2011, Ben Hutchings wrote:
>
> > On Thu, 2011-05-05 at 17:11 -0700, Greg KH wrote:
[...]
> > > - if (nsops < 1)
> > > + if (nsops < 1 || nsops > SEMOPM)
> > > return -EINVAL;
> >
> > It's not that important, but the manual page says the error code should
> > E2BIG in the latter case.
> >
>
> So something like this...
>
> Return correct error (E2BIG) when nsops is greater than SEMOPM in
> sys_oabi_semtimedop. The man page (semtimedop(2)) lists this as the proper
> error in ths case:
> "E2BIG The argument nsops is greater than SEMOPM, the maximum number of
> operations allowed per system call."
Looks right to me, not that I can test it.
Ben.
> Signed-off-by: Jesper Juhl <jj@...osbits.net>
> Reported-by: Ben Hutchings <ben@...adent.org.uk>
> --
> sys_oabi-compat.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/kernel/sys_oabi-compat.c b/arch/arm/kernel/sys_oabi-compat.c
> index af0aaeb..c196ad7 100644
> --- a/arch/arm/kernel/sys_oabi-compat.c
> +++ b/arch/arm/kernel/sys_oabi-compat.c
> @@ -311,8 +311,10 @@ asmlinkage long sys_oabi_semtimedop(int semid,
> long err;
> int i;
>
> - if (nsops < 1 || nsops > SEMOPM)
> + if (nsops < 1)
> return -EINVAL;
> + else if (nsops > SEMOPM)
> + return -E2BIG;
> sops = kmalloc(sizeof(*sops) * nsops, GFP_KERNEL);
> if (!sops)
> return -ENOMEM;
>
>
--
Ben Hutchings
We get into the habit of living before acquiring the habit of thinking.
- Albert Camus
--
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