diff mbox series

[net-next,05/14] ipv6: lockless IPV6_MINHOPCOUNT implementation

Message ID 20230912160212.3467976-6-edumazet@google.com (mailing list archive)
State Accepted
Commit 273784d3c5741522199011772651dbb50db8c810
Delegated to: Netdev Maintainers
Headers show
Series ipv6: round of data-races fixes | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next, async
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: 1340 this patch: 1340
netdev/cc_maintainers success CCed 6 of 6 maintainers
netdev/build_clang success Errors and warnings before: 1363 this patch: 1363
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: 1363 this patch: 1363
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 49 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Eric Dumazet Sept. 12, 2023, 4:02 p.m. UTC 
Add one missing READ_ONCE() annotation in do_ipv6_getsockopt()
and make IPV6_MINHOPCOUNT setsockopt() lockless.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 net/ipv6/ipv6_sockglue.c | 31 +++++++++++++++----------------
 1 file changed, 15 insertions(+), 16 deletions(-)

Comments

David Ahern Sept. 14, 2023, 3:01 p.m. UTC | #1 
On 9/12/23 10:02 AM, Eric Dumazet wrote:
> Add one missing READ_ONCE() annotation in do_ipv6_getsockopt()
> and make IPV6_MINHOPCOUNT setsockopt() lockless.
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> ---
>  net/ipv6/ipv6_sockglue.c | 31 +++++++++++++++----------------
>  1 file changed, 15 insertions(+), 16 deletions(-)
> 

Reviewed-by: David Ahern <dsahern@kernel.org>
diff mbox series

Patch

diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index 3b2a34828daab5c666d7b429afa961279739c70b..bbc8a009e05d3de49868e1ccf469a12bc31b8e22 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -448,6 +448,20 @@  int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
 			return -EINVAL;
 		WRITE_ONCE(np->frag_size, val);
 		return 0;
+	case IPV6_MINHOPCOUNT:
+		if (optlen < sizeof(int))
+			return -EINVAL;
+		if (val < 0 || val > 255)
+			return -EINVAL;
+
+		if (val)
+			static_branch_enable(&ip6_min_hopcount);
+
+		/* tcp_v6_err() and tcp_v6_rcv() might read min_hopcount
+		 * while we are changing it.
+		 */
+		WRITE_ONCE(np->min_hopcount, val);
+		return 0;
 	}
 	if (needs_rtnl)
 		rtnl_lock();
@@ -947,21 +961,6 @@  int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
 			goto e_inval;
 		retv = __ip6_sock_set_addr_preferences(sk, val);
 		break;
-	case IPV6_MINHOPCOUNT:
-		if (optlen < sizeof(int))
-			goto e_inval;
-		if (val < 0 || val > 255)
-			goto e_inval;
-
-		if (val)
-			static_branch_enable(&ip6_min_hopcount);
-
-		/* tcp_v6_err() and tcp_v6_rcv() might read min_hopcount
-		 * while we are changing it.
-		 */
-		WRITE_ONCE(np->min_hopcount, val);
-		retv = 0;
-		break;
 	case IPV6_DONTFRAG:
 		np->dontfrag = valbool;
 		retv = 0;
@@ -1443,7 +1442,7 @@  int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
 		break;
 
 	case IPV6_MINHOPCOUNT:
-		val = np->min_hopcount;
+		val = READ_ONCE(np->min_hopcount);
 		break;
 
 	case IPV6_DONTFRAG: