diff mbox series

[v1,net-next,7/9] phonet: Pass net and ifindex to rtm_phonet_notify().

Message ID 20241017183140.43028-8-kuniyu@amazon.com (mailing list archive)
State Accepted
Commit de51ad08b1177bbbb8b60cb7dd4c3c5dd50d262f
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 Errors and warnings before: 0 (+1) this patch: 0 (+1)
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: 13 this patch: 13
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 84 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 
Currently, rtm_phonet_notify() fetches netns and ifindex from dev.

Once route_doit() is converted to RCU, rtm_phonet_notify() will be
called outside of RCU due to GFP_KERNEL, and dev will be unavailable
there.

Let's pass net and ifindex to rtm_phonet_notify().

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
---
 include/net/phonet/pn_dev.h |  2 +-
 net/phonet/pn_dev.c         | 10 +++++++---
 net/phonet/pn_netlink.c     | 16 +++++++++-------
 3 files changed, 17 insertions(+), 11 deletions(-)

Comments

Eric Dumazet Oct. 23, 2024, 3:32 p.m. UTC | #1 
On Thu, Oct 17, 2024 at 8:34 PM Kuniyuki Iwashima <kuniyu@amazon.com> wrote:
>
> Currently, rtm_phonet_notify() fetches netns and ifindex from dev.
>
> Once route_doit() is converted to RCU, rtm_phonet_notify() will be
> called outside of RCU due to GFP_KERNEL, and dev will be unavailable
> there.
>
> Let's pass net and ifindex to rtm_phonet_notify().
>
> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
> ---

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

Patch

diff --git a/include/net/phonet/pn_dev.h b/include/net/phonet/pn_dev.h
index ac0331d83a81..021e524fd20a 100644
--- a/include/net/phonet/pn_dev.h
+++ b/include/net/phonet/pn_dev.h
@@ -43,7 +43,7 @@  void phonet_address_notify(struct net *net, int event, u32 ifindex, u8 addr);
 
 int phonet_route_add(struct net_device *dev, u8 daddr);
 int phonet_route_del(struct net_device *dev, u8 daddr);
-void rtm_phonet_notify(int event, struct net_device *dev, u8 dst);
+void rtm_phonet_notify(struct net *net, int event, u32 ifindex, u8 dst);
 struct net_device *phonet_route_get_rcu(struct net *net, u8 daddr);
 struct net_device *phonet_route_output(struct net *net, u8 daddr);
 
diff --git a/net/phonet/pn_dev.c b/net/phonet/pn_dev.c
index 545279ef5910..6ded0d347b9f 100644
--- a/net/phonet/pn_dev.c
+++ b/net/phonet/pn_dev.c
@@ -263,9 +263,13 @@  static int phonet_device_autoconf(struct net_device *dev)
 
 static void phonet_route_autodel(struct net_device *dev)
 {
-	struct phonet_net *pnn = phonet_pernet(dev_net(dev));
-	unsigned int i;
+	struct net *net = dev_net(dev);
 	DECLARE_BITMAP(deleted, 64);
+	u32 ifindex = dev->ifindex;
+	struct phonet_net *pnn;
+	unsigned int i;
+
+	pnn = phonet_pernet(net);
 
 	/* Remove left-over Phonet routes */
 	bitmap_zero(deleted, 64);
@@ -281,7 +285,7 @@  static void phonet_route_autodel(struct net_device *dev)
 		return; /* short-circuit RCU */
 	synchronize_rcu();
 	for_each_set_bit(i, deleted, 64) {
-		rtm_phonet_notify(RTM_DELROUTE, dev, i);
+		rtm_phonet_notify(net, RTM_DELROUTE, ifindex, i);
 		dev_put(dev);
 	}
 }
diff --git a/net/phonet/pn_netlink.c b/net/phonet/pn_netlink.c
index c9a4215ec560..bfec5bd639b6 100644
--- a/net/phonet/pn_netlink.c
+++ b/net/phonet/pn_netlink.c
@@ -200,7 +200,7 @@  static int fill_route(struct sk_buff *skb, u32 ifindex, u8 dst,
 	return -EMSGSIZE;
 }
 
-void rtm_phonet_notify(int event, struct net_device *dev, u8 dst)
+void rtm_phonet_notify(struct net *net, int event, u32 ifindex, u8 dst)
 {
 	struct sk_buff *skb;
 	int err = -ENOBUFS;
@@ -210,17 +210,17 @@  void rtm_phonet_notify(int event, struct net_device *dev, u8 dst)
 	if (skb == NULL)
 		goto errout;
 
-	err = fill_route(skb, dev->ifindex, dst, 0, 0, event);
+	err = fill_route(skb, ifindex, dst, 0, 0, event);
 	if (err < 0) {
 		WARN_ON(err == -EMSGSIZE);
 		kfree_skb(skb);
 		goto errout;
 	}
-	rtnl_notify(skb, dev_net(dev), 0,
-			  RTNLGRP_PHONET_ROUTE, NULL, GFP_KERNEL);
+
+	rtnl_notify(skb, net, 0, RTNLGRP_PHONET_ROUTE, NULL, GFP_KERNEL);
 	return;
 errout:
-	rtnl_set_sk_err(dev_net(dev), RTNLGRP_PHONET_ROUTE, err);
+	rtnl_set_sk_err(net, RTNLGRP_PHONET_ROUTE, err);
 }
 
 static const struct nla_policy rtm_phonet_policy[RTA_MAX+1] = {
@@ -235,6 +235,7 @@  static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
 	struct nlattr *tb[RTA_MAX+1];
 	struct net_device *dev;
 	struct rtmsg *rtm;
+	u32 ifindex;
 	int err;
 	u8 dst;
 
@@ -260,7 +261,8 @@  static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
 	if (dst & 3) /* Phonet addresses only have 6 high-order bits */
 		return -EINVAL;
 
-	dev = __dev_get_by_index(net, nla_get_u32(tb[RTA_OIF]));
+	ifindex = nla_get_u32(tb[RTA_OIF]);
+	dev = __dev_get_by_index(net, ifindex);
 	if (dev == NULL)
 		return -ENODEV;
 
@@ -269,7 +271,7 @@  static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
 	else
 		err = phonet_route_del(dev, dst);
 	if (!err)
-		rtm_phonet_notify(nlh->nlmsg_type, dev, dst);
+		rtm_phonet_notify(net, nlh->nlmsg_type, ifindex, dst);
 	return err;
 }