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 <hch@xxxxxx>
---
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
