Taehee Yoo 4c05ec4738 netfilter: nf_tables: fix suspicious RCU usage in nft_chain_stats_replace() ... basechain->stats is rcu protected data which is updated from nft_chain_stats_replace(). This function is executed from the commit phase which holds the pernet nf_tables commit mutex - not the global nfnetlink subsystem mutex. Test commands to reproduce the problem are: %iptables-nft -I INPUT %iptables-nft -Z %iptables-nft -Z This patch uses RCU calls to handle basechain->stats updates to fix a splat that looks like: [89279.358755] ============================= [89279.363656] WARNING: suspicious RCU usage [89279.368458] 4.20.0-rc2+ #44 Tainted: G W L [89279.374661] ----------------------------- [89279.379542] net/netfilter/nf_tables_api.c:1404 suspicious rcu_dereference_protected() usage! [...] [89279.406556] 1 lock held by iptables-nft/5225: [89279.411728] #0: 00000000bf45a000 (&net->nft.commit_mutex){+.+.}, at: nf_tables_valid_genid+0x1f/0x70 [nf_tables] [89279.424022] stack backtrace: [89279.429236] CPU: 0 PID: 5225 Comm: iptables-nft Tainted: G W L 4.20.0-rc2+ #44 [89279.430135] Call Trace: [89279.430135] dump_stack+0xc9/0x16b [89279.430135] ? show_regs_print_info+0x5/0x5 [89279.430135] ? lockdep_rcu_suspicious+0x117/0x160 [89279.430135] nft_chain_commit_update+0x4ea/0x640 [nf_tables] [89279.430135] ? sched_clock_local+0xd4/0x140 [89279.430135] ? check_flags.part.35+0x440/0x440 [89279.430135] ? __rhashtable_remove_fast.constprop.67+0xec0/0xec0 [nf_tables] [89279.430135] ? sched_clock_cpu+0x126/0x170 [89279.430135] ? find_held_lock+0x39/0x1c0 [89279.430135] ? hlock_class+0x140/0x140 [89279.430135] ? is_bpf_text_address+0x5/0xf0 [89279.430135] ? check_flags.part.35+0x440/0x440 [89279.430135] ? __lock_is_held+0xb4/0x140 [89279.430135] nf_tables_commit+0x2555/0x39c0 [nf_tables] Fixes: f102d66b33 ("netfilter: nf_tables: use dedicated mutex to guard transactions") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>		2018-12-04 01:37:13 +01:00
..
acpi	pci-v4.20-changes	2018-10-25 06:50:48 -07:00
asm-generic	s390 updates for 4.20-rc2	2018-11-09 06:30:44 -06:00
clocksource
crypto	KEYS: asym_tpm: extract key size & public key [ver #2]	2018-10-26 09:30:46 +01:00
drm	drm, i915, amdgpu, bridge + core quirk	2018-11-02 10:58:20 -07:00
dt-bindings	This time it looks like a quieter release cycle in the clk tree. I guess that's	2018-10-31 11:08:30 -07:00
keys	KEYS: Move trusted.h to include/keys [ver #2]	2018-10-26 09:30:47 +01:00
kvm
linux	netfilter: nf_tables: fix suspicious RCU usage in nft_chain_stats_replace()	2018-12-04 01:37:13 +01:00
math-emu
media	media: Rename vb2_m2m_request_queue -> v4l2_m2m_request_queue	2018-11-06 05:24:22 -05:00
memory
misc
net	Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf	2018-11-28 11:02:45 -08:00
pcmcia
ras
rdma	First merge window pull request	2018-10-26 07:38:19 -07:00
scsi
soc	ARM: SoC driver updates for 4.17	2018-10-29 15:16:01 -07:00
sound
target
trace	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2018-11-19 09:24:04 -08:00
uapi	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid	2018-11-24 12:58:47 -08:00
video
xen	CONFIG_XEN_PV breaks xen_create_contiguous_region on ARM	2018-11-02 17:18:34 +01:00