diff mbox series

[net-next] fib: rules: no longer hold RTNL in fib_nl_dumprule()

Message ID 20240411133340.1332796-1-edumazet@google.com (mailing list archive)
State Accepted
Commit 32affa5578f0e6b9abef3623d3976395afbd265c
Delegated to: Netdev Maintainers
Headers show
Series [net-next] fib: rules: no longer hold RTNL in fib_nl_dumprule() | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
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: 944 this patch: 944
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 2 maintainers not CCed: shaozhengchao@huawei.com dsahern@kernel.org
netdev/build_clang success Errors and warnings before: 954 this patch: 954
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: 955 this patch: 955
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 50 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-2024-04-12--06-00 (tests: 962)

Commit Message

Eric Dumazet April 11, 2024, 1:33 p.m. UTC 
- fib rules are already RCU protected, RTNL is not needed
  to get them.

- Fix return value at the end of a dump,
  so that NLMSG_DONE can be appended to current skb,
  saving one recvmsg() system call.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 net/core/fib_rules.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

Comments

David Ahern April 11, 2024, 3:39 p.m. UTC | #1 
On 4/11/24 7:33 AM, Eric Dumazet wrote:
> - fib rules are already RCU protected, RTNL is not needed
>   to get them.
> 
> - Fix return value at the end of a dump,
>   so that NLMSG_DONE can be appended to current skb,
>   saving one recvmsg() system call.
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> ---
>  net/core/fib_rules.c | 17 +++++++++--------
>  1 file changed, 9 insertions(+), 8 deletions(-)
> 

Reviewed-by: David Ahern <dsahern@kernel.org>
patchwork-bot+netdevbpf@kernel.org April 13, 2024, 2:20 a.m. UTC | #2 
Hello:

This patch was applied to netdev/net-next.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Thu, 11 Apr 2024 13:33:40 +0000 you wrote:
> - fib rules are already RCU protected, RTNL is not needed
>   to get them.
> 
> - Fix return value at the end of a dump,
>   so that NLMSG_DONE can be appended to current skb,
>   saving one recvmsg() system call.
> 
> [...]

Here is the summary with links:
  - [net-next] fib: rules: no longer hold RTNL in fib_nl_dumprule()
    https://git.kernel.org/netdev/net-next/c/32affa5578f0

You are awesome, thank you!
diff mbox series

Patch

diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c
index 3f933ffcefc3732ede48669cf0ab9e94fed46aac..6ebffbc632368168b621a3ee888ee558e88e2d4f 100644
--- a/net/core/fib_rules.c
+++ b/net/core/fib_rules.c
@@ -1142,10 +1142,10 @@  static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
 	const struct nlmsghdr *nlh = cb->nlh;
 	struct net *net = sock_net(skb->sk);
 	struct fib_rules_ops *ops;
-	int idx = 0, family;
+	int err, idx = 0, family;
 
 	if (cb->strict_check) {
-		int err = fib_valid_dumprule_req(nlh, cb->extack);
+		err = fib_valid_dumprule_req(nlh, cb->extack);
 
 		if (err < 0)
 			return err;
@@ -1158,17 +1158,17 @@  static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
 		if (ops == NULL)
 			return -EAFNOSUPPORT;
 
-		dump_rules(skb, cb, ops);
-
-		return skb->len;
+		return dump_rules(skb, cb, ops);
 	}
 
+	err = 0;
 	rcu_read_lock();
 	list_for_each_entry_rcu(ops, &net->rules_ops, list) {
 		if (idx < cb->args[0] || !try_module_get(ops->owner))
 			goto skip;
 
-		if (dump_rules(skb, cb, ops) < 0)
+		err = dump_rules(skb, cb, ops);
+		if (err < 0)
 			break;
 
 		cb->args[1] = 0;
@@ -1178,7 +1178,7 @@  static int fib_nl_dumprule(struct sk_buff *skb, struct netlink_callback *cb)
 	rcu_read_unlock();
 	cb->args[0] = idx;
 
-	return skb->len;
+	return err;
 }
 
 static void notify_rule_change(int event, struct fib_rule *rule,
@@ -1293,7 +1293,8 @@  static int __init fib_rules_init(void)
 	int err;
 	rtnl_register(PF_UNSPEC, RTM_NEWRULE, fib_nl_newrule, NULL, 0);
 	rtnl_register(PF_UNSPEC, RTM_DELRULE, fib_nl_delrule, NULL, 0);
-	rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule, 0);
+	rtnl_register(PF_UNSPEC, RTM_GETRULE, NULL, fib_nl_dumprule,
+		      RTNL_FLAG_DUMP_UNLOCKED);
 
 	err = register_pernet_subsys(&fib_rules_net_ops);
 	if (err < 0)