From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Date: Mon, 20 Jul 2020 12:47:14 +0000 Subject: [PATCH 01/24] bpfilter: reject kernel addresses Message-Id: <20200720124737.118617-2-hch@lst.de> List-Id: References: <20200720124737.118617-1-hch@lst.de> In-Reply-To: <20200720124737.118617-1-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: "David S. Miller" , Jakub Kicinski , Alexei Starovoitov , Daniel Borkmann , Alexey Kuznetsov , Hideaki YOSHIFUJI , Eric Dumazet Cc: linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, netfilter-devel@vger.kernel.org, coreteam@netfilter.org, linux-sctp@vger.kernel.org, linux-hams@vger.kernel.org, linux-bluetooth@vger.kernel.org, bridge@lists.linux-foundation.org, linux-can@vger.kernel.org, dccp@vger.kernel.org, linux-decnet-user@lists.sourceforge.net, linux-wpan@vger.kernel.org, linux-s390@vger.kernel.org, mptcp@lists.01.org, lvs-devel@vger.kernel.org, rds-devel@oss.oracle.com, linux-afs@lists.infradead.org, tipc-discussion@lists.sourceforge.net, linux-x25@vger.kernel.org When feeding addresses to userspace we can't support kernel addresses that were fed under set_fs(KERNEL_DS) from bpf-cgroup. Signed-off-by: Christoph Hellwig --- net/bpfilter/bpfilter_kern.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/bpfilter/bpfilter_kern.c b/net/bpfilter/bpfilter_kern.c index 2c31e82cb953af..977e9dad72ca4f 100644 --- a/net/bpfilter/bpfilter_kern.c +++ b/net/bpfilter/bpfilter_kern.c @@ -41,6 +41,11 @@ static int __bpfilter_process_sockopt(struct sock *sk, int optname, ssize_t n; int ret = -EFAULT; + if (uaccess_kernel()) { + pr_err("kernel access not supported\n"); + return -EFAULT; + } + req.is_set = is_set; req.pid = current->pid; req.cmd = optname; -- 2.27.0