3.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Pravin B Shelar <pshelar@xxxxxxxxxx>
[ Upstream commit 9b96309c5b0b9e466773c07a5bc8b7b68fcf010a ]
In case of genl-family with parallel ops off, dumpif() callback
is expected to run under genl_lock, But commit def3117493eafd9df
(genl: Allow concurrent genl callbacks.) changed this behaviour
where only first dumpit() op was called under genl-lock.
For subsequent dump, only nlk->cb_lock was taken.
Following patch fixes it by defining locked dumpit() and done()
callback which takes care of genl-locking.
Signed-off-by: Pravin B Shelar <pshelar@xxxxxxxxxx>
CC: Jesse Gross <jesse@xxxxxxxxxx>
CC: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/netlink/genetlink.c | 51 +++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 46 insertions(+), 5 deletions(-)
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -544,6 +544,30 @@ void *genlmsg_put(struct sk_buff *skb, u
}
EXPORT_SYMBOL(genlmsg_put);
+static int genl_lock_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
+{
+ struct genl_ops *ops = cb->data;
+ int rc;
+
+ genl_lock();
+ rc = ops->dumpit(skb, cb);
+ genl_unlock();
+ return rc;
+}
+
+static int genl_lock_done(struct netlink_callback *cb)
+{
+ struct genl_ops *ops = cb->data;
+ int rc = 0;
+
+ if (ops->done) {
+ genl_lock();
+ rc = ops->done(cb);
+ genl_unlock();
+ }
+ return rc;
+}
+
static int genl_family_rcv_msg(struct genl_family *family,
struct sk_buff *skb,
struct nlmsghdr *nlh)
@@ -572,15 +596,32 @@ static int genl_family_rcv_msg(struct ge
return -EPERM;
if (nlh->nlmsg_flags & NLM_F_DUMP) {
- struct netlink_dump_control c = {
- .dump = ops->dumpit,
- .done = ops->done,
- };
+ int rc;
if (ops->dumpit == NULL)
return -EOPNOTSUPP;
- return netlink_dump_start(net->genl_sock, skb, nlh, &c);
+ if (!family->parallel_ops) {
+ struct netlink_dump_control c = {
+ .data = ops,
+ .dump = genl_lock_dumpit,
+ .done = genl_lock_done,
+ };
+
+ genl_unlock();
+ rc = netlink_dump_start(net->genl_sock, skb, nlh, &c);
+ genl_lock();
+
+ } else {
+ struct netlink_dump_control c = {
+ .dump = ops->dumpit,
+ .done = ops->done,
+ };
+
+ rc = netlink_dump_start(net->genl_sock, skb, nlh, &c);
+ }
+
+ return rc;
}
if (ops->doit == NULL)
--
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