diff mbox series

[v1,net-next,9/9] phonet: Don't hold RTNL for route_doit().

Message ID 20241017183140.43028-10-kuniyu@amazon.com (mailing list archive)
State Accepted
Commit 17a1ac0018ae1cee0b2c2235ce54e91ecbbed7be
Delegated to: Netdev Maintainers
Headers show
Series phonet: Convert all doit() and dumpit() to RCU. | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 5 this patch: 5
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/build_clang success Errors and warnings before: 3 this patch: 3
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 4 this patch: 4
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 46 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-10-19--00-00 (tests: 777)

Commit Message

Kuniyuki Iwashima Oct. 17, 2024, 6:31 p.m. UTC 
Now only __dev_get_by_index() depends on RTNL in route_doit().

Let's use dev_get_by_index_rcu() and register route_doit() with
RTNL_FLAG_DOIT_UNLOCKED.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
---
 net/phonet/pn_netlink.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

Comments

Eric Dumazet Oct. 23, 2024, 3:34 p.m. UTC | #1 
On Thu, Oct 17, 2024 at 8:34 PM Kuniyuki Iwashima <kuniyu@amazon.com> wrote:
>
> Now only __dev_get_by_index() depends on RTNL in route_doit().
>
> Let's use dev_get_by_index_rcu() and register route_doit() with
> RTNL_FLAG_DOIT_UNLOCKED.
>
> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
> ---

Reviewed-by: Eric Dumazet <edumazet@google.com>
diff mbox series

Patch

diff --git a/net/phonet/pn_netlink.c b/net/phonet/pn_netlink.c
index bfec5bd639b6..ca1f04e4a2d9 100644
--- a/net/phonet/pn_netlink.c
+++ b/net/phonet/pn_netlink.c
@@ -245,8 +245,6 @@  static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
 	if (!netlink_capable(skb, CAP_SYS_ADMIN))
 		return -EPERM;
 
-	ASSERT_RTNL();
-
 	err = nlmsg_parse_deprecated(nlh, sizeof(*rtm), tb, RTA_MAX,
 				     rtm_phonet_policy, extack);
 	if (err < 0)
@@ -262,16 +260,25 @@  static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
 		return -EINVAL;
 
 	ifindex = nla_get_u32(tb[RTA_OIF]);
-	dev = __dev_get_by_index(net, ifindex);
-	if (dev == NULL)
+
+	rcu_read_lock();
+
+	dev = dev_get_by_index_rcu(net, ifindex);
+	if (!dev) {
+		rcu_read_unlock();
 		return -ENODEV;
+	}
 
 	if (nlh->nlmsg_type == RTM_NEWROUTE)
 		err = phonet_route_add(dev, dst);
 	else
 		err = phonet_route_del(dev, dst);
+
+	rcu_read_unlock();
+
 	if (!err)
 		rtm_phonet_notify(net, nlh->nlmsg_type, ifindex, dst);
+
 	return err;
 }
 
@@ -308,9 +315,9 @@  static const struct rtnl_msg_handler phonet_rtnl_msg_handlers[] __initdata_or_mo
 	{.owner = THIS_MODULE, .protocol = PF_PHONET, .msgtype = RTM_GETADDR,
 	 .dumpit = getaddr_dumpit, .flags = RTNL_FLAG_DUMP_UNLOCKED},
 	{.owner = THIS_MODULE, .protocol = PF_PHONET, .msgtype = RTM_NEWROUTE,
-	 .doit = route_doit},
+	 .doit = route_doit, .flags = RTNL_FLAG_DOIT_UNLOCKED},
 	{.owner = THIS_MODULE, .protocol = PF_PHONET, .msgtype = RTM_DELROUTE,
-	 .doit = route_doit},
+	 .doit = route_doit, .flags = RTNL_FLAG_DOIT_UNLOCKED},
 	{.owner = THIS_MODULE, .protocol = PF_PHONET, .msgtype = RTM_GETROUTE,
 	 .dumpit = route_dumpit, .flags = RTNL_FLAG_DUMP_UNLOCKED},
 };