diff options
author | Eric Dumazet <edumazet@google.com> | 2019-10-23 09:53:03 -0700 |
---|---|---|
committer | Simon Horman <horms@verge.net.au> | 2019-10-24 11:56:02 +0200 |
commit | c24b75e0f9239e78105f81c5f03a751641eb07ef (patch) | |
tree | 25b22e73798a8b701d8ccd56ed61de5ba4b38f32 | |
parent | 62931f59ce9cbabb934a431f48f2f1f441c605ac (diff) | |
download | linux-c24b75e0f9239e78105f81c5f03a751641eb07ef.tar.gz |
ipvs: move old_secure_tcp into struct netns_ipvs
syzbot reported the following issue :
BUG: KCSAN: data-race in update_defense_level / update_defense_level
read to 0xffffffff861a6260 of 4 bytes by task 3006 on cpu 1:
update_defense_level+0x621/0xb30 net/netfilter/ipvs/ip_vs_ctl.c:177
defense_work_handler+0x3d/0xd0 net/netfilter/ipvs/ip_vs_ctl.c:225
process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
worker_thread+0xa0/0x800 kernel/workqueue.c:2415
kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352
write to 0xffffffff861a6260 of 4 bytes by task 7333 on cpu 0:
update_defense_level+0xa62/0xb30 net/netfilter/ipvs/ip_vs_ctl.c:205
defense_work_handler+0x3d/0xd0 net/netfilter/ipvs/ip_vs_ctl.c:225
process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
worker_thread+0xa0/0x800 kernel/workqueue.c:2415
kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7333 Comm: kworker/0:5 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events defense_work_handler
Indeed, old_secure_tcp is currently a static variable, while it
needs to be a per netns variable.
Fixes: a0840e2e165a ("IPVS: netns, ip_vs_ctl local vars moved to ipvs struct.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
-rw-r--r-- | include/net/ip_vs.h | 1 | ||||
-rw-r--r-- | net/netfilter/ipvs/ip_vs_ctl.c | 15 |
2 files changed, 8 insertions, 8 deletions
diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h index 3759167f91f5..078887c8c586 100644 --- a/include/net/ip_vs.h +++ b/include/net/ip_vs.h @@ -889,6 +889,7 @@ struct netns_ipvs { struct delayed_work defense_work; /* Work handler */ int drop_rate; int drop_counter; + int old_secure_tcp; atomic_t dropentry; /* locks in ctl.c */ spinlock_t dropentry_lock; /* drop entry handling */ diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c index c8f81dd15c83..3cccc88ef817 100644 --- a/net/netfilter/ipvs/ip_vs_ctl.c +++ b/net/netfilter/ipvs/ip_vs_ctl.c @@ -93,7 +93,6 @@ static bool __ip_vs_addr_is_local_v6(struct net *net, static void update_defense_level(struct netns_ipvs *ipvs) { struct sysinfo i; - static int old_secure_tcp = 0; int availmem; int nomem; int to_change = -1; @@ -174,35 +173,35 @@ static void update_defense_level(struct netns_ipvs *ipvs) spin_lock(&ipvs->securetcp_lock); switch (ipvs->sysctl_secure_tcp) { case 0: - if (old_secure_tcp >= 2) + if (ipvs->old_secure_tcp >= 2) to_change = 0; break; case 1: if (nomem) { - if (old_secure_tcp < 2) + if (ipvs->old_secure_tcp < 2) to_change = 1; ipvs->sysctl_secure_tcp = 2; } else { - if (old_secure_tcp >= 2) + if (ipvs->old_secure_tcp >= 2) to_change = 0; } break; case 2: if (nomem) { - if (old_secure_tcp < 2) + if (ipvs->old_secure_tcp < 2) to_change = 1; } else { - if (old_secure_tcp >= 2) + if (ipvs->old_secure_tcp >= 2) to_change = 0; ipvs->sysctl_secure_tcp = 1; } break; case 3: - if (old_secure_tcp < 2) + if (ipvs->old_secure_tcp < 2) to_change = 1; break; } - old_secure_tcp = ipvs->sysctl_secure_tcp; + ipvs->old_secure_tcp = ipvs->sysctl_secure_tcp; if (to_change >= 0) ip_vs_protocol_timeout_change(ipvs, ipvs->sysctl_secure_tcp > 1); |