diff mbox series

[net-next,10/13] ipv6: annotate data-races around devconf->disable_policy

Message ID 20240226155055.1141336-11-edumazet@google.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series ipv6: lockless accesses to devconf | 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: 941 this patch: 941
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/build_clang success Errors and warnings before: 957 this patch: 957
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: 958 this patch: 958
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 28 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-2024-02-27--03-00 (tests: 1456)

Commit Message

Eric Dumazet Feb. 26, 2024, 3:50 p.m. UTC 
idev->cnf.disable_policy and net->ipv6.devconf_all->disable_policy
can be read locklessly. Add appropriate annotations on reads
and writes.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 net/ipv6/addrconf.c   | 2 +-
 net/ipv6/ip6_output.c | 4 ++--
 net/ipv6/route.c      | 4 ++--
 3 files changed, 5 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index f2a91bdda23f808d38640d3f3ec91140386bc640..8ba024f227b43fcba11fbfac1f3a9691841efcbf 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -6698,7 +6698,7 @@  int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
 	if (!rtnl_trylock())
 		return restart_syscall();
 
-	*valp = val;
+	WRITE_ONCE(*valp, val);
 
 	net = (struct net *)ctl->extra2;
 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index f08af3f4e54f5dcb0b8b5fb8f60463e41bd1f578..b9dd3a66e4236fbf67af75c5f98c921b38c18bf6 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -513,8 +513,8 @@  int ip6_forward(struct sk_buff *skb)
 	if (skb_warn_if_lro(skb))
 		goto drop;
 
-	if (!net->ipv6.devconf_all->disable_policy &&
-	    (!idev || !idev->cnf.disable_policy) &&
+	if (!READ_ONCE(net->ipv6.devconf_all->disable_policy) &&
+	    (!idev || !READ_ONCE(idev->cnf.disable_policy)) &&
 	    !xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) {
 		__IP6_INC_STATS(net, idev, IPSTATS_MIB_INDISCARDS);
 		goto drop;
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 1b897c57c55fe22eff71a22b51ad25269db622f5..a92fcac902aea9307e0c83d150e9d1c41435887f 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -4584,8 +4584,8 @@  struct fib6_info *addrconf_f6i_alloc(struct net *net,
 		f6i->dst_nocount = true;
 
 		if (!anycast &&
-		    (net->ipv6.devconf_all->disable_policy ||
-		     idev->cnf.disable_policy))
+		    (READ_ONCE(net->ipv6.devconf_all->disable_policy) ||
+		     READ_ONCE(idev->cnf.disable_policy)))
 			f6i->dst_nopolicy = true;
 	}