298977887/lede
1
0
Fork 0
mirror of https://github.com/coolsnowwolf/lede.git synced 2025-04-15 18:03:30 +00:00
Code Issues Packages Projects Releases Wiki Activity
33e376de95
lede/package/kernel/mac80211/patches/build/236-fix-genlmsg_multicast_allns-build-error.patch
coolsnowwolf 33e376de95 kernel: bump 5.4 to 5.4.287
2024-12-18 21:56:26 +08:00

178 lines
6.5 KiB
Diff
Raw Blame History

From e0f83d268974dab0361d11904dfc9acec53f96a6 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <edumazet@google.com>
Date: Fri, 11 Oct 2024 17:12:17 +0000
Subject: [PATCH] genetlink: hold RCU in genlmsg_mcast()
[ Upstream commit 56440d7ec28d60f8da3bfa09062b3368ff9b16db ]
While running net selftests with CONFIG_PROVE_RCU_LIST=y I saw
one lockdep splat [1].
genlmsg_mcast() uses for_each_net_rcu(), and must therefore hold RCU.
Instead of letting all callers guard genlmsg_multicast_allns()
with a rcu_read_lock()/rcu_read_unlock() pair, do it in genlmsg_mcast().
This also means the @flags parameter is useless, we need to always use
GFP_ATOMIC.
[1]
[10882.424136] =============================
[10882.424166] WARNING: suspicious RCU usage
[10882.424309] 6.12.0-rc2-virtme #1156 Not tainted
[10882.424400] -----------------------------
[10882.424423] net/netlink/genetlink.c:1940 RCU-list traversed in non-reader section!!
[10882.424469]
other info that might help us debug this:
[10882.424500]
rcu_scheduler_active = 2, debug_locks = 1
[10882.424744] 2 locks held by ip/15677:
[10882.424791] #0: ffffffffb6b491b0 (cb_lock){++++}-{3:3}, at: genl_rcv (net/netlink/genetlink.c:1219)
[10882.426334] #1: ffffffffb6b49248 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg (net/netlink/genetlink.c:61 net/netlink/genetlink.c:57 net/netlink/genetlink.c:1209)
[10882.426465]
stack backtrace:
[10882.426805] CPU: 14 UID: 0 PID: 15677 Comm: ip Not tainted 6.12.0-rc2-virtme #1156
[10882.426919] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[10882.427046] Call Trace:
[10882.427131] <TASK>
[10882.427244] dump_stack_lvl (lib/dump_stack.c:123)
[10882.427335] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822)
[10882.427387] genlmsg_multicast_allns (net/netlink/genetlink.c:1940 (discriminator 7) net/netlink/genetlink.c:1977 (discriminator 7))
[10882.427436] l2tp_tunnel_notify.constprop.0 (net/l2tp/l2tp_netlink.c:119) l2tp_netlink
[10882.427683] l2tp_nl_cmd_tunnel_create (net/l2tp/l2tp_netlink.c:253) l2tp_netlink
[10882.427748] genl_family_rcv_msg_doit (net/netlink/genetlink.c:1115)
[10882.427834] genl_rcv_msg (net/netlink/genetlink.c:1195 net/netlink/genetlink.c:1210)
[10882.427877] ? __pfx_l2tp_nl_cmd_tunnel_create (net/l2tp/l2tp_netlink.c:186) l2tp_netlink
[10882.427927] ? __pfx_genl_rcv_msg (net/netlink/genetlink.c:1201)
[10882.427959] netlink_rcv_skb (net/netlink/af_netlink.c:2551)
[10882.428069] genl_rcv (net/netlink/genetlink.c:1220)
[10882.428095] netlink_unicast (net/netlink/af_netlink.c:1332 net/netlink/af_netlink.c:1357)
[10882.428140] netlink_sendmsg (net/netlink/af_netlink.c:1901)
[10882.428210] ____sys_sendmsg (net/socket.c:729 (discriminator 1) net/socket.c:744 (discriminator 1) net/socket.c:2607 (discriminator 1))
Fixes: 33f72e6f0c67 ("l2tp : multicast notification to the registered listeners")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: James Chapman <jchapman@katalix.com>
Cc: Tom Parkin <tparkin@katalix.com>
Cc: Johannes Berg <johannes.berg@intel.com>
Link: https://patch.msgid.link/20241011171217.3166614-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/target/target_core_user.c | 2 +-
include/net/genetlink.h | 3 +--
net/l2tp/l2tp_netlink.c | 4 ++--
net/netlink/genetlink.c | 28 ++++++++++++++--------------
net/wireless/nl80211.c | 8 ++------
5 files changed, 20 insertions(+), 25 deletions(-)
--- a/backport-include/net/genetlink.h
+++ b/backport-include/net/genetlink.h
@@ -150,7 +150,7 @@ int genlmsg_multicast(const struct genl_
#define genlmsg_multicast_allns LINUX_BACKPORT(genlmsg_multicast_allns)
int backport_genlmsg_multicast_allns(const struct genl_family *family,
struct sk_buff *skb, u32 portid,
- unsigned int group, gfp_t flags);
+ unsigned int group);
#define genl_family_attrbuf LINUX_BACKPORT(genl_family_attrbuf)
static inline struct nlattr **genl_family_attrbuf(struct genl_family *family)
--- a/compat/backport-genetlink.c
+++ b/compat/backport-genetlink.c
@@ -198,23 +198,23 @@ int genlmsg_multicast(const struct genl_
}
EXPORT_SYMBOL_GPL(genlmsg_multicast);
-static int genlmsg_mcast(struct sk_buff *skb, u32 portid, unsigned long group,
- gfp_t flags)
+static int genlmsg_mcast(struct sk_buff *skb, u32 portid, unsigned long group)
{
struct sk_buff *tmp;
struct net *net, *prev = NULL;
bool delivered = false;
int err;
+ rcu_read_lock();
for_each_net_rcu(net) {
if (prev) {
- tmp = skb_clone(skb, flags);
+ tmp = skb_clone(skb, GFP_ATOMIC);
if (!tmp) {
err = -ENOMEM;
goto error;
}
err = nlmsg_multicast(prev->genl_sock, tmp,
- portid, group, flags);
+ portid, group, GFP_ATOMIC);
if (!err)
delivered = true;
else if (err != -ESRCH)
@@ -223,25 +223,29 @@ static int genlmsg_mcast(struct sk_buff
prev = net;
}
+ err = nlmsg_multicast(prev->genl_sock, skb, portid, group, GFP_ATOMIC);
+
+ rcu_read_unlock();
- err = nlmsg_multicast(prev->genl_sock, skb, portid, group, flags);
if (!err)
delivered = true;
else if (err != -ESRCH)
return err;
return delivered ? 0 : -ESRCH;
error:
+ rcu_read_unlock();
+
kfree_skb(skb);
return err;
}
int backport_genlmsg_multicast_allns(const struct genl_family *family,
struct sk_buff *skb, u32 portid,
- unsigned int group, gfp_t flags)
+ unsigned int group)
{
group = __backport_genl_group(family, group);
if (group == INVALID_GROUP)
return -EINVAL;
- return genlmsg_mcast(skb, portid, group, flags);
+ return genlmsg_mcast(skb, portid, group);
}
EXPORT_SYMBOL_GPL(backport_genlmsg_multicast_allns);
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -17596,10 +17596,15 @@
genlmsg_end(msg, hdr);
+#if LINUX_VERSION_IS_GEQ(6,6,59) || LINUX_VERSION_IS_GEQ(6,1,115) || LINUX_VERSION_IS_GEQ(5,10,230) || LINUX_VERSION_IS_GEQ(5,4,283)
+ genlmsg_multicast_allns(&nl80211_fam, msg, 0,
+ NL80211_MCGRP_REGULATORY);
+#else
rcu_read_lock();
genlmsg_multicast_allns(&nl80211_fam, msg, 0,
NL80211_MCGRP_REGULATORY, GFP_ATOMIC);
rcu_read_unlock();
+#endif
return;
@@ -18217,10 +18222,15 @@
genlmsg_end(msg, hdr);
+#if LINUX_VERSION_IS_GEQ(6,6,59) || LINUX_VERSION_IS_GEQ(6,1,115) || LINUX_VERSION_IS_GEQ(5,10,230) || LINUX_VERSION_IS_GEQ(5,4,283)
+ genlmsg_multicast_allns(&nl80211_fam, msg, 0,
+ NL80211_MCGRP_REGULATORY);
+#else
rcu_read_lock();
genlmsg_multicast_allns(&nl80211_fam, msg, 0,
NL80211_MCGRP_REGULATORY, GFP_ATOMIC);
rcu_read_unlock();
+#endif
return;
Reference in New Issue View Git Blame Copy Permalink