diff options
| author | Juhee Kang | 2022-02-19 15:29:59 +0000 |
|---|---|---|
| committer | David S. Miller | 2022-02-19 16:39:45 +0000 |
| commit | e7f27420681f23e7e0f28beed38144058752112e (patch) | |
| tree | 0b3788376ed56e8a2f4a64bc77ad24187df0ba8f | |
| parent | 92c54a65e6a82a897a9fecaae8de6c57682ba510 (diff) | |
net: hsr: fix suspicious RCU usage warning in hsr_node_get_first()
When hsr_create_self_node() calls hsr_node_get_first(), the suspicious
RCU usage warning is occurred. The reason why this warning is raised is
the callers of hsr_node_get_first() use rcu_read_lock_bh() and
other different synchronization mechanisms. Thus, this patch solved by
replacing rcu_dereference() with rcu_dereference_bh_check().
The kernel test robot reports:
[ 50.083470][ T3596] =============================
[ 50.088648][ T3596] WARNING: suspicious RCU usage
[ 50.093785][ T3596] 5.17.0-rc3-next-20220208-syzkaller #0 Not tainted
[ 50.100669][ T3596] -----------------------------
[ 50.105513][ T3596] net/hsr/hsr_framereg.c:34 suspicious rcu_dereference_check() usage!
[ 50.113799][ T3596]
[ 50.113799][ T3596] other info that might help us debug this:
[ 50.113799][ T3596]
[ 50.124257][ T3596]
[ 50.124257][ T3596] rcu_scheduler_active = 2, debug_locks = 1
[ 50.132368][ T3596] 2 locks held by syz-executor.0/3596:
[ 50.137863][ T3596] #0: ffffffff8d3357e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3be/0xb80
[ 50.147470][ T3596] #1: ffff88807ec9d5f0 (&hsr->list_lock){+...}-{2:2}, at: hsr_create_self_node+0x225/0x650
[ 50.157623][ T3596]
[ 50.157623][ T3596] stack backtrace:
[ 50.163510][ T3596] CPU: 1 PID: 3596 Comm: syz-executor.0 Not tainted 5.17.0-rc3-next-20220208-syzkaller #0
[ 50.173381][ T3596] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 50.183623][ T3596] Call Trace:
[ 50.186904][ T3596] <TASK>
[ 50.189844][ T3596] dump_stack_lvl+0xcd/0x134
[ 50.194640][ T3596] hsr_node_get_first+0x9b/0xb0
[ 50.199499][ T3596] hsr_create_self_node+0x22d/0x650
[ 50.204688][ T3596] hsr_dev_finalize+0x2c1/0x7d0
[ 50.209669][ T3596] hsr_newlink+0x315/0x730
[ 50.214113][ T3596] ? hsr_dellink+0x130/0x130
[ 50.218789][ T3596] ? rtnl_create_link+0x7e8/0xc00
[ 50.223803][ T3596] ? hsr_dellink+0x130/0x130
[ 50.228397][ T3596] __rtnl_newlink+0x107c/0x1760
[ 50.233249][ T3596] ? rtnl_setlink+0x3c0/0x3c0
[ 50.238043][ T3596] ? is_bpf_text_address+0x77/0x170
[ 50.243362][ T3596] ? lock_downgrade+0x6e0/0x6e0
[ 50.248219][ T3596] ? unwind_next_frame+0xee1/0x1ce0
[ 50.253605][ T3596] ? entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 50.259669][ T3596] ? __sanitizer_cov_trace_cmp4+0x1c/0x70
[ 50.265423][ T3596] ? is_bpf_text_address+0x99/0x170
[ 50.270819][ T3596] ? kernel_text_address+0x39/0x80
[ 50.275950][ T3596] ? __kernel_text_address+0x9/0x30
[ 50.281336][ T3596] ? unwind_get_return_address+0x51/0x90
[ 50.286975][ T3596] ? create_prof_cpu_mask+0x20/0x20
[ 50.292178][ T3596] ? arch_stack_walk+0x93/0xe0
[ 50.297172][ T3596] ? kmem_cache_alloc_trace+0x42/0x2c0
[ 50.302637][ T3596] ? rcu_read_lock_sched_held+0x3a/0x70
[ 50.308194][ T3596] rtnl_newlink+0x64/0xa0
[ 50.312524][ T3596] ? __rtnl_newlink+0x1760/0x1760
[ 50.317545][ T3596] rtnetlink_rcv_msg+0x413/0xb80
[ 50.322631][ T3596] ? rtnl_newlink+0xa0/0xa0
[ 50.327159][ T3596] netlink_rcv_skb+0x153/0x420
[ 50.331931][ T3596] ? rtnl_newlink+0xa0/0xa0
[ 50.336436][ T3596] ? netlink_ack+0xa80/0xa80
[ 50.341095][ T3596] ? netlink_deliver_tap+0x1a2/0xc40
[ 50.346532][ T3596] ? netlink_deliver_tap+0x1b1/0xc40
[ 50.351839][ T3596] netlink_unicast+0x539/0x7e0
[ 50.356633][ T3596] ? netlink_attachskb+0x880/0x880
[ 50.361750][ T3596] ? __sanitizer_cov_trace_const_cmp8+0x1d/0x70
[ 50.368003][ T3596] ? __sanitizer_cov_trace_const_cmp8+0x1d/0x70
[ 50.374707][ T3596] ? __phys_addr_symbol+0x2c/0x70
[ 50.379753][ T3596] ? __sanitizer_cov_trace_cmp8+0x1d/0x70
[ 50.385568][ T3596] ? __check_object_size+0x16c/0x4f0
[ 50.390859][ T3596] netlink_sendmsg+0x904/0xe00
[ 50.395715][ T3596] ? netlink_unicast+0x7e0/0x7e0
[ 50.400722][ T3596] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70
[ 50.407003][ T3596] ? netlink_unicast+0x7e0/0x7e0
[ 50.412119][ T3596] sock_sendmsg+0xcf/0x120
[ 50.416548][ T3596] __sys_sendto+0x21c/0x320
[ 50.421052][ T3596] ? __ia32_sys_getpeername+0xb0/0xb0
[ 50.426427][ T3596] ? lockdep_hardirqs_on_prepare+0x400/0x400
[ 50.432721][ T3596] ? __context_tracking_exit+0xb8/0xe0
[ 50.438188][ T3596] ? lock_downgrade+0x6e0/0x6e0
[ 50.443041][ T3596] ? lock_downgrade+0x6e0/0x6e0
[ 50.447902][ T3596] __x64_sys_sendto+0xdd/0x1b0
[ 50.452759][ T3596] ? lockdep_hardirqs_on+0x79/0x100
[ 50.457964][ T3596] ? syscall_enter_from_user_mode+0x21/0x70
[ 50.464150][ T3596] do_syscall_64+0x35/0xb0
[ 50.468565][ T3596] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 50.474452][ T3596] RIP: 0033:0x7f3148504e1c
[ 50.479052][ T3596] Code: fa fa ff ff 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 20 fb ff ff 48 8b
[ 50.498926][ T3596] RSP: 002b:00007ffeab5f2ab0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
[ 50.507342][ T3596] RAX: ffffffffffffffda RBX: 00007f314959d320 RCX: 00007f3148504e1c
[ 50.515393][ T3596] RDX: 0000000000000048 RSI: 00007f314959d370 RDI: 0000000000000003
[ 50.523444][ T3596] RBP: 0000000000000000 R08: 00007ffeab5f2b04 R09: 000000000000000c
[ 50.531492][ T3596] R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
[ 50.539455][ T3596] R13: 00007f314959d370 R14: 0000000000000003 R15: 0000000000000000
Fixes: 4acc45db7115 ("net: hsr: use hlist_head instead of list_head for mac addresses")
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Reported-and-tested-by: syzbot+f0eb4f3876de066b128c@syzkaller.appspotmail.com
Signed-off-by: Juhee Kang <claudiajkang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/hsr/hsr_framereg.c | 16 | ||||
| -rw-r--r-- | net/hsr/hsr_framereg.h | 2 |
2 files changed, 11 insertions, 7 deletions
diff --git a/net/hsr/hsr_framereg.c b/net/hsr/hsr_framereg.c index b3c6ffa1894d..62272d76545c 100644 --- a/net/hsr/hsr_framereg.c +++ b/net/hsr/hsr_framereg.c @@ -27,11 +27,11 @@ u32 hsr_mac_hash(struct hsr_priv *hsr, const unsigned char *addr) return reciprocal_scale(hash, hsr->hash_buckets); } -struct hsr_node *hsr_node_get_first(struct hlist_head *head) +struct hsr_node *hsr_node_get_first(struct hlist_head *head, int cond) { struct hlist_node *first; - first = rcu_dereference(hlist_first_rcu(head)); + first = rcu_dereference_bh_check(hlist_first_rcu(head), cond); if (first) return hlist_entry(first, struct hsr_node, mac_list); @@ -59,7 +59,8 @@ bool hsr_addr_is_self(struct hsr_priv *hsr, unsigned char *addr) { struct hsr_node *node; - node = hsr_node_get_first(&hsr->self_node_db); + node = hsr_node_get_first(&hsr->self_node_db, + lockdep_is_held(&hsr->list_lock)); if (!node) { WARN_ONCE(1, "HSR: No self node\n"); return false; @@ -106,7 +107,8 @@ int hsr_create_self_node(struct hsr_priv *hsr, ether_addr_copy(node->macaddress_B, addr_b); spin_lock_bh(&hsr->list_lock); - oldnode = hsr_node_get_first(self_node_db); + oldnode = hsr_node_get_first(self_node_db, + lockdep_is_held(&hsr->list_lock)); if (oldnode) { hlist_replace_rcu(&oldnode->mac_list, &node->mac_list); spin_unlock_bh(&hsr->list_lock); @@ -125,7 +127,8 @@ void hsr_del_self_node(struct hsr_priv *hsr) struct hsr_node *node; spin_lock_bh(&hsr->list_lock); - node = hsr_node_get_first(self_node_db); + node = hsr_node_get_first(self_node_db, + lockdep_is_held(&hsr->list_lock)); if (node) { hlist_del_rcu(&node->mac_list); kfree_rcu(node, rcu_head); @@ -597,7 +600,8 @@ void *hsr_get_next_node(struct hsr_priv *hsr, void *_pos, hash = hsr_mac_hash(hsr, addr); if (!_pos) { - node = hsr_node_get_first(&hsr->node_db[hash]); + node = hsr_node_get_first(&hsr->node_db[hash], + lockdep_is_held(&hsr->list_lock)); if (node) ether_addr_copy(addr, node->macaddress_A); return node; diff --git a/net/hsr/hsr_framereg.h b/net/hsr/hsr_framereg.h index d7cce6b161e3..2efd03fb3465 100644 --- a/net/hsr/hsr_framereg.h +++ b/net/hsr/hsr_framereg.h @@ -29,7 +29,7 @@ struct hsr_frame_info { }; u32 hsr_mac_hash(struct hsr_priv *hsr, const unsigned char *addr); -struct hsr_node *hsr_node_get_first(struct hlist_head *head); +struct hsr_node *hsr_node_get_first(struct hlist_head *head, int cond); void hsr_del_self_node(struct hsr_priv *hsr); void hsr_del_nodes(struct hlist_head *node_db); struct hsr_node *hsr_get_node(struct hsr_port *port, struct hlist_head *node_db, |