diff mbox series

[net-next,1/3] inet: annotate devconf data-races

Message ID 20240227092411.2315725-2-edumazet@google.com (mailing list archive)
State Accepted
Commit 0598f8f3bb77893a13105d47bb7dfe42f1dc1f4e
Delegated to: Netdev Maintainers
Headers show
Series inet: implement lockless RTM_GETNETCONF ops | 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: 1284 this patch: 1284
netdev/build_tools success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/build_clang success Errors and warnings before: 962 this patch: 962
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: 1411 this patch: 1411
netdev/checkpatch warning CHECK: No space is necessary after a cast
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-2024-02-27--12-00 (tests: 1453)

Commit Message

Eric Dumazet Feb. 27, 2024, 9:24 a.m. UTC 
Add READ_ONCE() in ipv4_devconf_get() and corresponding
WRITE_ONCE() in ipv4_devconf_set()

Add IPV4_DEVCONF_RO() and IPV4_DEVCONF_ALL_RO() macros,
and use them when reading devconf fields.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 include/linux/inetdevice.h | 14 ++++++++------
 net/ipv4/devinet.c         | 21 +++++++++++----------
 net/ipv4/igmp.c            |  4 ++--
 net/ipv4/proc.c            |  2 +-
 net/ipv4/route.c           |  4 ++--
 5 files changed, 24 insertions(+), 21 deletions(-)

Comments

Jiri Pirko Feb. 27, 2024, 12:59 p.m. UTC | #1 
Tue, Feb 27, 2024 at 10:24:09AM CET, edumazet@google.com wrote:
>Add READ_ONCE() in ipv4_devconf_get() and corresponding
>WRITE_ONCE() in ipv4_devconf_set()
>
>Add IPV4_DEVCONF_RO() and IPV4_DEVCONF_ALL_RO() macros,
>and use them when reading devconf fields.
>
>Signed-off-by: Eric Dumazet <edumazet@google.com>

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
diff mbox series

Patch

diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h
index ddb27fc0ee8c8862d62f8c6243c4239ea53374f2..cb5280e6cc219106bcc55972dac850edf34988ff 100644
--- a/include/linux/inetdevice.h
+++ b/include/linux/inetdevice.h
@@ -53,13 +53,15 @@  struct in_device {
 };
 
 #define IPV4_DEVCONF(cnf, attr) ((cnf).data[IPV4_DEVCONF_ ## attr - 1])
+#define IPV4_DEVCONF_RO(cnf, attr) READ_ONCE(IPV4_DEVCONF(cnf, attr))
 #define IPV4_DEVCONF_ALL(net, attr) \
 	IPV4_DEVCONF((*(net)->ipv4.devconf_all), attr)
+#define IPV4_DEVCONF_ALL_RO(net, attr) READ_ONCE(IPV4_DEVCONF_ALL(net, attr))
 
-static inline int ipv4_devconf_get(struct in_device *in_dev, int index)
+static inline int ipv4_devconf_get(const struct in_device *in_dev, int index)
 {
 	index--;
-	return in_dev->cnf.data[index];
+	return READ_ONCE(in_dev->cnf.data[index]);
 }
 
 static inline void ipv4_devconf_set(struct in_device *in_dev, int index,
@@ -67,7 +69,7 @@  static inline void ipv4_devconf_set(struct in_device *in_dev, int index,
 {
 	index--;
 	set_bit(index, in_dev->cnf.state);
-	in_dev->cnf.data[index] = val;
+	WRITE_ONCE(in_dev->cnf.data[index], val);
 }
 
 static inline void ipv4_devconf_setall(struct in_device *in_dev)
@@ -81,18 +83,18 @@  static inline void ipv4_devconf_setall(struct in_device *in_dev)
 	ipv4_devconf_set((in_dev), IPV4_DEVCONF_ ## attr, (val))
 
 #define IN_DEV_ANDCONF(in_dev, attr) \
-	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), attr) && \
+	(IPV4_DEVCONF_ALL_RO(dev_net(in_dev->dev), attr) && \
 	 IN_DEV_CONF_GET((in_dev), attr))
 
 #define IN_DEV_NET_ORCONF(in_dev, net, attr) \
-	(IPV4_DEVCONF_ALL(net, attr) || \
+	(IPV4_DEVCONF_ALL_RO(net, attr) || \
 	 IN_DEV_CONF_GET((in_dev), attr))
 
 #define IN_DEV_ORCONF(in_dev, attr) \
 	IN_DEV_NET_ORCONF(in_dev, dev_net(in_dev->dev), attr)
 
 #define IN_DEV_MAXCONF(in_dev, attr) \
-	(max(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), attr), \
+	(max(IPV4_DEVCONF_ALL_RO(dev_net(in_dev->dev), attr), \
 	     IN_DEV_CONF_GET((in_dev), attr)))
 
 #define IN_DEV_FORWARD(in_dev)		IN_DEV_CONF_GET((in_dev), FORWARDING)
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index bc74f131fe4dfad327e71c1a8f0a4b66cdc526e5..ca75d0fff1d1ebd8c199fb74a6f0e2f51160635c 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -1982,7 +1982,7 @@  static int inet_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
 		return -EMSGSIZE;
 
 	for (i = 0; i < IPV4_DEVCONF_MAX; i++)
-		((u32 *) nla_data(nla))[i] = in_dev->cnf.data[i];
+		((u32 *) nla_data(nla))[i] = READ_ONCE(in_dev->cnf.data[i]);
 
 	return 0;
 }
@@ -2068,9 +2068,9 @@  static int inet_netconf_msgsize_devconf(int type)
 }
 
 static int inet_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
-				     struct ipv4_devconf *devconf, u32 portid,
-				     u32 seq, int event, unsigned int flags,
-				     int type)
+				     const struct ipv4_devconf *devconf,
+				     u32 portid, u32 seq, int event,
+				     unsigned int flags, int type)
 {
 	struct nlmsghdr  *nlh;
 	struct netconfmsg *ncm;
@@ -2095,27 +2095,28 @@  static int inet_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
 
 	if ((all || type == NETCONFA_FORWARDING) &&
 	    nla_put_s32(skb, NETCONFA_FORWARDING,
-			IPV4_DEVCONF(*devconf, FORWARDING)) < 0)
+			IPV4_DEVCONF_RO(*devconf, FORWARDING)) < 0)
 		goto nla_put_failure;
 	if ((all || type == NETCONFA_RP_FILTER) &&
 	    nla_put_s32(skb, NETCONFA_RP_FILTER,
-			IPV4_DEVCONF(*devconf, RP_FILTER)) < 0)
+			IPV4_DEVCONF_RO(*devconf, RP_FILTER)) < 0)
 		goto nla_put_failure;
 	if ((all || type == NETCONFA_MC_FORWARDING) &&
 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
-			IPV4_DEVCONF(*devconf, MC_FORWARDING)) < 0)
+			IPV4_DEVCONF_RO(*devconf, MC_FORWARDING)) < 0)
 		goto nla_put_failure;
 	if ((all || type == NETCONFA_BC_FORWARDING) &&
 	    nla_put_s32(skb, NETCONFA_BC_FORWARDING,
-			IPV4_DEVCONF(*devconf, BC_FORWARDING)) < 0)
+			IPV4_DEVCONF_RO(*devconf, BC_FORWARDING)) < 0)
 		goto nla_put_failure;
 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH,
-			IPV4_DEVCONF(*devconf, PROXY_ARP)) < 0)
+			IPV4_DEVCONF_RO(*devconf, PROXY_ARP)) < 0)
 		goto nla_put_failure;
 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
-			IPV4_DEVCONF(*devconf, IGNORE_ROUTES_WITH_LINKDOWN)) < 0)
+			IPV4_DEVCONF_RO(*devconf,
+					IGNORE_ROUTES_WITH_LINKDOWN)) < 0)
 		goto nla_put_failure;
 
 out:
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index efeeca2b13285a3149645ab945b0364391f6721b..717e97a389a8aee75f51a5a5d859cb94a5d868eb 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -120,12 +120,12 @@ 
  */
 
 #define IGMP_V1_SEEN(in_dev) \
-	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \
+	(IPV4_DEVCONF_ALL_RO(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 1 || \
 	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 1 || \
 	 ((in_dev)->mr_v1_seen && \
 	  time_before(jiffies, (in_dev)->mr_v1_seen)))
 #define IGMP_V2_SEEN(in_dev) \
-	(IPV4_DEVCONF_ALL(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \
+	(IPV4_DEVCONF_ALL_RO(dev_net(in_dev->dev), FORCE_IGMP_VERSION) == 2 || \
 	 IN_DEV_CONF_GET((in_dev), FORCE_IGMP_VERSION) == 2 || \
 	 ((in_dev)->mr_v2_seen && \
 	  time_before(jiffies, (in_dev)->mr_v2_seen)))
diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c
index 5f4654ebff487494b6afbaa69174df4c004395dc..914bc9c35cc702395aee257fb010034294e501de 100644
--- a/net/ipv4/proc.c
+++ b/net/ipv4/proc.c
@@ -395,7 +395,7 @@  static int snmp_seq_show_ipstats(struct seq_file *seq, void *v)
 		seq_printf(seq, " %s", snmp4_ipstats_list[i].name);
 
 	seq_printf(seq, "\nIp: %d %d",
-		   IPV4_DEVCONF_ALL(net, FORWARDING) ? 1 : 2,
+		   IPV4_DEVCONF_ALL_RO(net, FORWARDING) ? 1 : 2,
 		   READ_ONCE(net->ipv4.sysctl_ip_default_ttl));
 
 	BUILD_BUG_ON(offsetof(struct ipstats_mib, mibs) != 0);
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index b512288d6fcc6bc0ce586bc5dc501b979ac3b9c1..c8f76f56dc1653371ca39663f29cc798b062e60d 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2313,7 +2313,7 @@  static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 		if (IN_DEV_BFORWARD(in_dev))
 			goto make_route;
 		/* not do cache if bc_forwarding is enabled */
-		if (IPV4_DEVCONF_ALL(net, BC_FORWARDING))
+		if (IPV4_DEVCONF_ALL_RO(net, BC_FORWARDING))
 			do_cache = false;
 		goto brd_input;
 	}
@@ -2993,7 +2993,7 @@  static int rt_fill_info(struct net *net, __be32 dst, __be32 src,
 #ifdef CONFIG_IP_MROUTE
 			if (ipv4_is_multicast(dst) &&
 			    !ipv4_is_local_multicast(dst) &&
-			    IPV4_DEVCONF_ALL(net, MC_FORWARDING)) {
+			    IPV4_DEVCONF_ALL_RO(net, MC_FORWARDING)) {
 				int err = ipmr_get_route(net, skb,
 							 fl4->saddr, fl4->daddr,
 							 r, portid);