diff mbox series

[net-next,02/13] ip_tunnel: annotate data-races around t->parms.link

Message ID 20240207142629.3456570-3-edumazet@google.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series net: complete dev_base_lock removal | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next, async
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: 1048 this patch: 1048
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 1 maintainers not CCed: dsahern@kernel.org
netdev/build_clang success Errors and warnings before: 1065 this patch: 1065
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: 1065 this patch: 1065
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 80 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 fail net-next-2024-02-08--03-00 (tests: 774)

Commit Message

Eric Dumazet Feb. 7, 2024, 2:26 p.m. UTC 
t->parms.link is read locklessly, annotate these reads
and opposite writes accordingly.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 net/ipv4/ip_tunnel.c | 27 +++++++++++++--------------
 1 file changed, 13 insertions(+), 14 deletions(-)
diff mbox series

Patch

diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index beeae624c412d752bd5ee5d459a88f57640445e9..b8e846b2863741903528a41126cf29419ed63324 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -102,10 +102,9 @@  struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
 		if (!ip_tunnel_key_match(&t->parms, flags, key))
 			continue;
 
-		if (t->parms.link == link)
+		if (READ_ONCE(t->parms.link) == link)
 			return t;
-		else
-			cand = t;
+		cand = t;
 	}
 
 	hlist_for_each_entry_rcu(t, head, hash_node) {
@@ -117,9 +116,9 @@  struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
 		if (!ip_tunnel_key_match(&t->parms, flags, key))
 			continue;
 
-		if (t->parms.link == link)
+		if (READ_ONCE(t->parms.link) == link)
 			return t;
-		else if (!cand)
+		if (!cand)
 			cand = t;
 	}
 
@@ -137,9 +136,9 @@  struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
 		if (!ip_tunnel_key_match(&t->parms, flags, key))
 			continue;
 
-		if (t->parms.link == link)
+		if (READ_ONCE(t->parms.link) == link)
 			return t;
-		else if (!cand)
+		if (!cand)
 			cand = t;
 	}
 
@@ -150,9 +149,9 @@  struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
 		    !(t->dev->flags & IFF_UP))
 			continue;
 
-		if (t->parms.link == link)
+		if (READ_ONCE(t->parms.link) == link)
 			return t;
-		else if (!cand)
+		if (!cand)
 			cand = t;
 	}
 
@@ -221,7 +220,7 @@  static struct ip_tunnel *ip_tunnel_find(struct ip_tunnel_net *itn,
 	hlist_for_each_entry_rcu(t, head, hash_node) {
 		if (local == t->parms.iph.saddr &&
 		    remote == t->parms.iph.daddr &&
-		    link == t->parms.link &&
+		    link == READ_ONCE(t->parms.link) &&
 		    type == t->dev->type &&
 		    ip_tunnel_key_match(&t->parms, flags, key))
 			break;
@@ -747,7 +746,7 @@  void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
 
 	ip_tunnel_init_flow(&fl4, protocol, dst, tnl_params->saddr,
 			    tunnel->parms.o_key, RT_TOS(tos),
-			    dev_net(dev), tunnel->parms.link,
+			    dev_net(dev), READ_ONCE(tunnel->parms.link),
 			    tunnel->fwmark, skb_get_hash(skb), 0);
 
 	if (ip_tunnel_encap(skb, &tunnel->encap, &protocol, &fl4) < 0)
@@ -867,7 +866,7 @@  static void ip_tunnel_update(struct ip_tunnel_net *itn,
 	if (t->parms.link != p->link || t->fwmark != fwmark) {
 		int mtu;
 
-		t->parms.link = p->link;
+		WRITE_ONCE(t->parms.link, p->link);
 		t->fwmark = fwmark;
 		mtu = ip_tunnel_bind_dev(dev);
 		if (set_mtu)
@@ -1057,9 +1056,9 @@  EXPORT_SYMBOL(ip_tunnel_get_link_net);
 
 int ip_tunnel_get_iflink(const struct net_device *dev)
 {
-	struct ip_tunnel *tunnel = netdev_priv(dev);
+	const struct ip_tunnel *tunnel = netdev_priv(dev);
 
-	return tunnel->parms.link;
+	return READ_ONCE(tunnel->parms.link);
 }
 EXPORT_SYMBOL(ip_tunnel_get_iflink);