net/bpfilter: split __bpfilter_process_sockopt

Split __bpfilter_process_sockopt into a low-level send request routine and
the actual setsockopt hook to split the init time ping from the actual
setsockopt processing.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Christoph Hellwig 2020-07-23 08:08:44 +02:00 committed by David S. Miller
parent e024e00818
commit c9ffebdde8

View File

@ -31,48 +31,51 @@ static void __stop_umh(void)
shutdown_umh();
}
static int __bpfilter_process_sockopt(struct sock *sk, int optname,
char __user *optval,
unsigned int optlen, bool is_set)
static int bpfilter_send_req(struct mbox_request *req)
{
struct mbox_request req;
struct mbox_reply reply;
loff_t pos;
ssize_t n;
int ret = -EFAULT;
req.is_set = is_set;
req.pid = current->pid;
req.cmd = optname;
req.addr = (uintptr_t)optval;
req.len = optlen;
if (!bpfilter_ops.info.tgid)
goto out;
return -EFAULT;
pos = 0;
n = kernel_write(bpfilter_ops.info.pipe_to_umh, &req, sizeof(req),
n = kernel_write(bpfilter_ops.info.pipe_to_umh, req, sizeof(*req),
&pos);
if (n != sizeof(req)) {
if (n != sizeof(*req)) {
pr_err("write fail %zd\n", n);
__stop_umh();
ret = -EFAULT;
goto out;
goto stop;
}
pos = 0;
n = kernel_read(bpfilter_ops.info.pipe_from_umh, &reply, sizeof(reply),
&pos);
if (n != sizeof(reply)) {
pr_err("read fail %zd\n", n);
__stop_umh();
ret = -EFAULT;
goto out;
goto stop;
}
ret = reply.status;
out:
return ret;
return reply.status;
stop:
__stop_umh();
return -EFAULT;
}
static int bpfilter_process_sockopt(struct sock *sk, int optname,
char __user *optval, unsigned int optlen,
bool is_set)
{
struct mbox_request req = {
.is_set = is_set,
.pid = current->pid,
.cmd = optname,
.addr = (uintptr_t)optval,
.len = optlen,
};
return bpfilter_send_req(&req);
}
static int start_umh(void)
{
struct mbox_request req = { .pid = current->pid };
int err;
/* fork usermode process */
@ -82,7 +85,7 @@ static int start_umh(void)
pr_info("Loaded bpfilter_umh pid %d\n", pid_nr(bpfilter_ops.info.tgid));
/* health check that usermode process started correctly */
if (__bpfilter_process_sockopt(NULL, 0, NULL, 0, 0) != 0) {
if (bpfilter_send_req(&req) != 0) {
shutdown_umh();
return -EFAULT;
}
@ -103,7 +106,7 @@ static int __init load_umh(void)
mutex_lock(&bpfilter_ops.lock);
err = start_umh();
if (!err && IS_ENABLED(CONFIG_INET)) {
bpfilter_ops.sockopt = &__bpfilter_process_sockopt;
bpfilter_ops.sockopt = &bpfilter_process_sockopt;
bpfilter_ops.start = &start_umh;
}
mutex_unlock(&bpfilter_ops.lock);