diff mbox series

[net-next,4/5] ipmr: use READ_ONCE() to read net->ipv[46].ipmr_seq

Message ID 20241009184405.3752829-5-edumazet@google.com (mailing list archive)
State Accepted
Commit 055202b16c589cc82cc8ab9d4316701547fb8853
Delegated to: Netdev Maintainers
Headers show
Series net: remove RTNL from fib_seq_sum() | 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: 6 this patch: 6
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: 6 this patch: 6
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: 9 this patch: 9
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 52 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 1 this patch: 1
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-10-11--15-00 (tests: 776)

Commit Message

Eric Dumazet Oct. 9, 2024, 6:44 p.m. UTC 
mr_call_vif_notifiers() and mr_call_mfc_notifiers() already
uses WRITE_ONCE() on the write side.

Using RTNL to protect the reads seems a big hammer.

Constify 'struct net' argument of ip6mr_rules_seq_read()
and ipmr_rules_seq_read().

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 net/ipv4/ipmr.c  | 8 +++-----
 net/ipv6/ip6mr.c | 8 +++-----
 2 files changed, 6 insertions(+), 10 deletions(-)

Comments

Kuniyuki Iwashima Oct. 10, 2024, 12:05 a.m. UTC | #1 
From: Eric Dumazet <edumazet@google.com>
Date: Wed,  9 Oct 2024 18:44:04 +0000
> mr_call_vif_notifiers() and mr_call_mfc_notifiers() already
> uses WRITE_ONCE() on the write side.
> 
> Using RTNL to protect the reads seems a big hammer.
> 
> Constify 'struct net' argument of ip6mr_rules_seq_read()
> and ipmr_rules_seq_read().
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
diff mbox series

Patch

diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 089864c6a35eec146a1ba90c22d79245f8e48158..35ed0316518424c7742a93bd72d56295e1eb01aa 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -288,7 +288,7 @@  static int ipmr_rules_dump(struct net *net, struct notifier_block *nb,
 	return fib_rules_dump(net, nb, RTNL_FAMILY_IPMR, extack);
 }
 
-static unsigned int ipmr_rules_seq_read(struct net *net)
+static unsigned int ipmr_rules_seq_read(const struct net *net)
 {
 	return fib_rules_seq_read(net, RTNL_FAMILY_IPMR);
 }
@@ -346,7 +346,7 @@  static int ipmr_rules_dump(struct net *net, struct notifier_block *nb,
 	return 0;
 }
 
-static unsigned int ipmr_rules_seq_read(struct net *net)
+static unsigned int ipmr_rules_seq_read(const struct net *net)
 {
 	return 0;
 }
@@ -3037,9 +3037,7 @@  static const struct net_protocol pim_protocol = {
 
 static unsigned int ipmr_seq_read(struct net *net)
 {
-	ASSERT_RTNL();
-
-	return net->ipv4.ipmr_seq + ipmr_rules_seq_read(net);
+	return READ_ONCE(net->ipv4.ipmr_seq) + ipmr_rules_seq_read(net);
 }
 
 static int ipmr_dump(struct net *net, struct notifier_block *nb,
diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index 2ce4ae0d8dc3b443986d7a7b4177a057f5affaec..3f9501fd8c1ae583d4862128e8620ce6cc114d25 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -276,7 +276,7 @@  static int ip6mr_rules_dump(struct net *net, struct notifier_block *nb,
 	return fib_rules_dump(net, nb, RTNL_FAMILY_IP6MR, extack);
 }
 
-static unsigned int ip6mr_rules_seq_read(struct net *net)
+static unsigned int ip6mr_rules_seq_read(const struct net *net)
 {
 	return fib_rules_seq_read(net, RTNL_FAMILY_IP6MR);
 }
@@ -335,7 +335,7 @@  static int ip6mr_rules_dump(struct net *net, struct notifier_block *nb,
 	return 0;
 }
 
-static unsigned int ip6mr_rules_seq_read(struct net *net)
+static unsigned int ip6mr_rules_seq_read(const struct net *net)
 {
 	return 0;
 }
@@ -1262,9 +1262,7 @@  static int ip6mr_device_event(struct notifier_block *this,
 
 static unsigned int ip6mr_seq_read(struct net *net)
 {
-	ASSERT_RTNL();
-
-	return net->ipv6.ipmr_seq + ip6mr_rules_seq_read(net);
+	return READ_ONCE(net->ipv6.ipmr_seq) + ip6mr_rules_seq_read(net);
 }
 
 static int ip6mr_dump(struct net *net, struct notifier_block *nb,