diff options
| author | Taehee Yoo <ap420073@gmail.com> | 2019-01-09 02:24:53 +0900 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-01-11 18:05:41 -0800 |
| commit | 61fbf5933d42b02f552123af5a87a06335a3b4db (patch) | |
| tree | b7e58c69a150b8624bb32c4f28cea3de3e1fcedd /net/ipv4 | |
| parent | 5b4cb650e569db2e6a09d2fa0ef8eb789a0ac5d8 (diff) | |
| download | linux-61fbf5933d42b02f552123af5a87a06335a3b4db.tar.bz2 | |
net: bpfilter: restart bpfilter_umh when error occurred
The bpfilter_umh will be stopped via __stop_umh() when the bpfilter
error occurred.
The bpfilter_umh() couldn't start again because there is no restart
routine.
The section of the bpfilter_umh_{start/end} is no longer .init.rodata
because these area should be reused in the restart routine. hence
the section name is changed to .bpfilter_umh.
The bpfilter_ops->start() is restart callback. it will be called when
bpfilter_umh is stopped.
The stop bit means bpfilter_umh is stopped. this bit is set by both
start and stop routine.
Before this patch,
Test commands:
$ iptables -vnL
$ kill -9 <pid of bpfilter_umh>
$ iptables -vnL
[ 480.045136] bpfilter: write fail -32
$ iptables -vnL
All iptables commands will fail.
After this patch,
Test commands:
$ iptables -vnL
$ kill -9 <pid of bpfilter_umh>
$ iptables -vnL
$ iptables -vnL
Now, all iptables commands will work.
Fixes: d2ba09c17a06 ("net: add skeleton of bpfilter kernel module")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/bpfilter/sockopt.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/net/ipv4/bpfilter/sockopt.c b/net/ipv4/bpfilter/sockopt.c index c326cfbc0f62..de84ede4e765 100644 --- a/net/ipv4/bpfilter/sockopt.c +++ b/net/ipv4/bpfilter/sockopt.c @@ -14,6 +14,7 @@ EXPORT_SYMBOL_GPL(bpfilter_ops); static void bpfilter_umh_cleanup(struct umh_info *info) { + bpfilter_ops.stop = true; fput(info->pipe_to_umh); fput(info->pipe_from_umh); info->pid = 0; @@ -23,14 +24,21 @@ static int bpfilter_mbox_request(struct sock *sk, int optname, char __user *optval, unsigned int optlen, bool is_set) { + int err; + if (!bpfilter_ops.sockopt) { - int err = request_module("bpfilter"); + err = request_module("bpfilter"); if (err) return err; if (!bpfilter_ops.sockopt) return -ECHILD; } + if (bpfilter_ops.stop) { + err = bpfilter_ops.start(); + if (err) + return err; + } return bpfilter_ops.sockopt(sk, optname, optval, optlen, is_set); } @@ -53,6 +61,7 @@ int bpfilter_ip_get_sockopt(struct sock *sk, int optname, char __user *optval, static int __init bpfilter_sockopt_init(void) { + bpfilter_ops.stop = true; bpfilter_ops.info.cmdline = "bpfilter_umh"; bpfilter_ops.info.cleanup = &bpfilter_umh_cleanup; |