From: Sasha Levin <sashal@kernel•org>
To: linux-kernel@vger•kernel.org, stable@vger•kernel.org
Cc: Eric Dumazet <edumazet@google•com>,
"David S . Miller" <davem@davemloft•net>,
Sasha Levin <sashal@kernel•org>,
kuba@kernel•org, pabeni@redhat•com, akpm@linux-foundation•org,
mhiramat@kernel•org, rostedt@goodmis•org, vbabka@suse•cz,
ahalaney@redhat•com, wangkefeng.wang@huawei•com,
linux@rasmusvillemoes•dk, keescook@chromium•org,
mark-pk.tsai@mediatek•com, peterz@infradead•org,
valentin.schneider@arm•com, bigeasy@linutronix•de,
toke@redhat•com, imagedong@tencent•com, petrm@nvidia•com,
memxor@gmail•com, arnd@arndb•de, changbin.du@intel•com,
yajun.deng@linux•dev, hmukos@yandex-team•ru,
netdev@vger•kernel.org
Subject: [PATCH AUTOSEL 5.16 034/109] net: initialize init_net earlier
Date: Fri, 1 Apr 2022 10:31:41 -0400 [thread overview]
Message-ID: <20220401143256.1950537-34-sashal@kernel.org> (raw)
In-Reply-To: <20220401143256.1950537-1-sashal@kernel.org>
From: Eric Dumazet <edumazet@google•com>
[ Upstream commit 9c1be1935fb68b2413796cdc03d019b8cf35ab51 ]
While testing a patch that will follow later
("net: add netns refcount tracker to struct nsproxy")
I found that devtmpfs_init() was called before init_net
was initialized.
This is a bug, because devtmpfs_setup() calls
ksys_unshare(CLONE_NEWNS);
This has the effect of increasing init_net refcount,
which will be later overwritten to 1, as part of setup_net(&init_net)
We had too many prior patches [1] trying to work around the root cause.
Really, make sure init_net is in BSS section, and that net_ns_init()
is called earlier at boot time.
Note that another patch ("vfs: add netns refcount tracker
to struct fs_context") also will need net_ns_init() being called
before vfs_caches_init()
As a bonus, this patch saves around 4KB in .data section.
[1]
f8c46cb39079 ("netns: do not call pernet ops for not yet set up init_net namespace")
b5082df8019a ("net: Initialise init_net.count to 1")
734b65417b24 ("net: Statically initialize init_net.dev_base_head")
v2: fixed a build error reported by kernel build bots (CONFIG_NET=n)
Signed-off-by: Eric Dumazet <edumazet@google•com>
Signed-off-by: David S. Miller <davem@davemloft•net>
Signed-off-by: Sasha Levin <sashal@kernel•org>
---
include/net/net_namespace.h | 6 ++++++
init/main.c | 2 ++
net/core/dev.c | 3 +--
net/core/net_namespace.c | 17 +++++------------
4 files changed, 14 insertions(+), 14 deletions(-)
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index bb5fa5914032..2ba326f9e004 100644
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -479,4 +479,10 @@ static inline void fnhe_genid_bump(struct net *net)
atomic_inc(&net->fnhe_genid);
}
+#ifdef CONFIG_NET
+void net_ns_init(void);
+#else
+static inline void net_ns_init(void) {}
+#endif
+
#endif /* __NET_NET_NAMESPACE_H */
diff --git a/init/main.c b/init/main.c
index bb984ed79de0..cb68bc48a682 100644
--- a/init/main.c
+++ b/init/main.c
@@ -99,6 +99,7 @@
#include <linux/kcsan.h>
#include <linux/init_syscalls.h>
#include <linux/stackdepot.h>
+#include <net/net_namespace.h>
#include <asm/io.h>
#include <asm/bugs.h>
@@ -1113,6 +1114,7 @@ asmlinkage __visible void __init __no_sanitize_address start_kernel(void)
key_init();
security_init();
dbg_late_init();
+ net_ns_init();
vfs_caches_init();
pagecache_init();
signals_init();
diff --git a/net/core/dev.c b/net/core/dev.c
index 2078d04c6482..8c47e0f2075d 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -11403,8 +11403,7 @@ static int __net_init netdev_init(struct net *net)
BUILD_BUG_ON(GRO_HASH_BUCKETS >
8 * sizeof_field(struct napi_struct, gro_bitmask));
- if (net != &init_net)
- INIT_LIST_HEAD(&net->dev_base_head);
+ INIT_LIST_HEAD(&net->dev_base_head);
net->dev_name_head = netdev_create_hash();
if (net->dev_name_head == NULL)
diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index 9702d2b0d920..9745cb6fdf51 100644
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -44,13 +44,7 @@ EXPORT_SYMBOL_GPL(net_rwsem);
static struct key_tag init_net_key_domain = { .usage = REFCOUNT_INIT(1) };
#endif
-struct net init_net = {
- .ns.count = REFCOUNT_INIT(1),
- .dev_base_head = LIST_HEAD_INIT(init_net.dev_base_head),
-#ifdef CONFIG_KEYS
- .key_domain = &init_net_key_domain,
-#endif
-};
+struct net init_net;
EXPORT_SYMBOL(init_net);
static bool init_net_initialized;
@@ -1081,7 +1075,7 @@ static void rtnl_net_notifyid(struct net *net, int cmd, int id, u32 portid,
rtnl_set_sk_err(net, RTNLGRP_NSID, err);
}
-static int __init net_ns_init(void)
+void __init net_ns_init(void)
{
struct net_generic *ng;
@@ -1102,6 +1096,9 @@ static int __init net_ns_init(void)
rcu_assign_pointer(init_net.gen, ng);
+#ifdef CONFIG_KEYS
+ init_net.key_domain = &init_net_key_domain;
+#endif
down_write(&pernet_ops_rwsem);
if (setup_net(&init_net, &init_user_ns))
panic("Could not setup the initial network namespace");
@@ -1116,12 +1113,8 @@ static int __init net_ns_init(void)
RTNL_FLAG_DOIT_UNLOCKED);
rtnl_register(PF_UNSPEC, RTM_GETNSID, rtnl_net_getid, rtnl_net_dumpid,
RTNL_FLAG_DOIT_UNLOCKED);
-
- return 0;
}
-pure_initcall(net_ns_init);
-
static void free_exit_list(struct pernet_operations *ops, struct list_head *net_exit_list)
{
ops_pre_exit_list(ops, net_exit_list);
--
2.34.1
next prev parent reply other threads:[~2022-04-01 14:50 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20220401143256.1950537-1-sashal@kernel.org>
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 002/109] ath5k: fix OOB in ath5k_eeprom_read_pcal_info_5111 Sasha Levin
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 013/109] ptp: replace snprintf with sysfs_emit Sasha Levin
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 014/109] selftests, xsk: Fix bpf_res cleanup test Sasha Levin
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 019/109] ath11k: fix kernel panic during unload/load ath11k modules Sasha Levin
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 020/109] ath11k: pci: fix crash on suspend if board file is not found Sasha Levin
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 021/109] ath11k: mhi: use mhi_sync_power_up() Sasha Levin
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 022/109] net/smc: Send directly when TCP_CORK is cleared Sasha Levin
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 024/109] bpf: Make dst_port field in struct bpf_sock 16-bit wide Sasha Levin
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 029/109] mt76: mt7921: fix crash when startup fails Sasha Levin
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 030/109] mt76: dma: initialize skip_unmap in mt76_dma_rx_fill Sasha Levin
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 031/109] cfg80211: don't add non transmitted BSS to 6GHz scanned channels Sasha Levin
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 032/109] libbpf: Fix build issue with llvm-readelf Sasha Levin
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 033/109] ipv6: make mc_forwarding atomic Sasha Levin
2022-04-01 14:31 ` Sasha Levin [this message]
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 044/109] tcp: Don't acquire inet_listen_hashbucket::lock with disabled BH Sasha Levin
2022-04-01 14:31 ` [PATCH AUTOSEL 5.16 051/109] net/mlx5e: Disable TX queues before registering the netdev Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 053/109] iwlwifi: mvm: Correctly set fragmented EBS Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 054/109] iwlwifi: mvm: Passively scan non PSC channels only when requested so Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 055/109] iwlwifi: fix small doc mistake for iwl_fw_ini_addr_val Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 056/109] iwlwifi: mvm: move only to an enabled channel Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 058/109] rtw89: fix RCU usage in rtw89_core_txq_push() Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 059/109] ipv4: Invalidate neighbour for broadcast address upon address addition Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 069/109] mt76: mt7915: fix injected MPDU transmission to not use HW A-MSDU Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 072/109] mt76: mt7615: Fix assigning negative values to unsigned variable Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 076/109] net/smc: correct settings of RMB window update limit Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 078/109] macvtap: advertise link netns via netlink Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 079/109] tuntap: add sanity checks about msg_controllen in sendmsg Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 081/109] Bluetooth: Fix not checking for valid hdev on bt_dev_{info,warn,err,dbg} Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 082/109] Bluetooth: use memset avoid memory leaks Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 083/109] bnxt_en: Eliminate unintended link toggle during FW reset Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 086/109] powerpc/64e: Tie PPC_BOOK3E_64 to PPC_FSL_BOOK3E Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 089/109] can: isotp: set default value for N_As to 50 micro seconds Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 090/109] can: etas_es58x: es58x_fd_rx_event_msg(): initialize rx_event_msg before calling es58x_check_msg_len() Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 092/109] net: account alternate interface name memory Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 093/109] net: limit altnames to 64k total Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 094/109] net/mlx5e: Remove overzealous validations in netlink EEPROM query Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 097/109] net: sfp: add 2500base-X quirk for Lantech SFP module Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 099/109] mt76: fix monitor mode crash with sdio driver Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 102/109] Bluetooth: Fix use after free in hci_send_acl Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 103/109] netfilter: conntrack: revisit gc autotuning Sasha Levin
2022-04-01 14:32 ` [PATCH AUTOSEL 5.16 104/109] netlabel: fix out-of-bounds memory accesses Sasha Levin
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