Messages in this thread | | | Date | Mon, 27 Nov 2006 22:56:45 +0100 | From | "Jesper Juhl" <> | Subject | Re: [PATCH] potential NULL pointer deref in net/key/af_key.c |
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On 27/11/06, David Miller <davem@davemloft.net> wrote: > From: Jesper Juhl <jesper.juhl@gmail.com> > Date: Mon, 27 Nov 2006 22:44:07 +0100 > > > In net/key/af_key.c::pfkey_send_policy_notify() there's a check at the > > beginning of the function : > > > > if (xp && xp->type != XFRM_POLICY_TYPE_MAIN) > > > > this implies that 'xp' may be null when the function is called. But later > > on in the function we have this code : > > > > return key_notify_policy(xp, dir, c); > > > > key_notify_policy() passes 'xp' to pfkey_xfrm_policy2msg_prep() that pass > > it on to pfkey_xfrm_policy2msg_size() which dereferences it. > > key_notify_policy() also passes 'xp' to pfkey_xfrm_policy2msg() which > > also dereferences it. > > > > So, in pfkey_send_policy_notify() in the cases where we end up calling > > key_notify_policy(), we should test 'xp' for NULL. > > > > (note: patch is compile tested only) > > > > > > Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> > > We really need to teach your automated tool about context. > > The NULL case can only occur for XFRM_MSG_FLUSHPOLICY. > > Look at the km_policy_notify() call sites. You can even see from the > net/xfrm/xfrm_user.c:xfrm_send_policy_notify() implementation of this > callback that for XFRM_MSG_FLUSHPOLICY the "xp" argument is ignored. > Arrgh, you are right. I really need to check call sites more carefully :(
-- Jesper Juhl <jesper.juhl@gmail.com> Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html Plain text mails only, please http://www.expita.com/nomime.html - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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