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 PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Thu, 26 Sep 2019 00:21:12 +0100 From: Al Viro <viro@...iv.linux.org.uk> To: Navid Emamdoost <navid.emamdoost@...il.com> Cc: emamd001@....edu, smccaman@....edu, kjlu@....edu, "David S. Miller" <davem@...emloft.net>, netdev@...r.kernel.org, linux-kernel@...r.kernel.org Subject: Re: [PATCH] net: qrtr: fix memory leak in qrtr_tun_read_iter On Wed, Sep 25, 2019 at 06:04:13PM -0500, Navid Emamdoost wrote: > In qrtr_tun_read_iter we need an error handling path to appropriately > release skb in cases of error. Release _what_ skb? > Signed-off-by: Navid Emamdoost <navid.emamdoost@...il.com> > --- > net/qrtr/tun.c | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) > > diff --git a/net/qrtr/tun.c b/net/qrtr/tun.c > index e35869e81766..0f6e6d1d2901 100644 > --- a/net/qrtr/tun.c > +++ b/net/qrtr/tun.c > @@ -54,19 +54,24 @@ static ssize_t qrtr_tun_read_iter(struct kiocb *iocb, struct iov_iter *to) > int count; > > while (!(skb = skb_dequeue(&tun->queue))) { The body of the loop is entered only if the loop condition has evaluated true. In this case, it means that the value of !(skb = skb_dequeue(&tun->queue)) had been true, i.e. the value of skb = skb_dequeue(&tun->queue) has been NULL, i.e. that skb_dequeue() has returned NULL, which had been copied into skb. In other words, in the body of that loop we have skb equal to NULL. > - if (filp->f_flags & O_NONBLOCK) > - return -EAGAIN; > + if (filp->f_flags & O_NONBLOCK) { > + count = -EAGAIN; > + goto out; > + } > > /* Wait until we get data or the endpoint goes away */ > if (wait_event_interruptible(tun->readq, > - !skb_queue_empty(&tun->queue))) > - return -ERESTARTSYS; > + !skb_queue_empty(&tun->queue))) { > + count = -ERESTARTSYS; > + goto out; > + } > } The meaning of that loop is fairly clear, isn't it? Keep looking int tun->queue until an skb shows up there. If it's not immediately there, fail with -EAGAIN for non-blocking files and wait on tun->readq until some skb arrives.
Powered by blists - more mailing lists