diff options
| author | Eric Dumazet <edumazet@google.com> | 2022-06-23 04:34:35 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2022-06-24 11:34:37 +0100 |
| commit | 121fefc669bf6f603bbda380c91d788405bc4f1f (patch) | |
| tree | 11a475f2c934f2cffd0441aad4aa41b995c6768c /net/ipv4/ipmr.c | |
| parent | 646679881a02a15a0915f4cd18dff6cecb8960fc (diff) | |
| download | linux-121fefc669bf6f603bbda380c91d788405bc4f1f.tar.bz2 | |
ipmr: do not acquire mrt_lock in __pim_rcv()
rcu_read_lock() protection is more than enough.
vif_dev_read() supports either mrt_lock or rcu_read_lock().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/ipmr.c')
| -rw-r--r-- | net/ipv4/ipmr.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c index 8fe7a688cf41..8a94f9a459cd 100644 --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -582,6 +582,7 @@ static int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb, { struct net_device *reg_dev = NULL; struct iphdr *encap; + int vif_num; encap = (struct iphdr *)(skb_transport_header(skb) + pimlen); /* Check that: @@ -594,11 +595,10 @@ static int __pim_rcv(struct mr_table *mrt, struct sk_buff *skb, ntohs(encap->tot_len) + pimlen > skb->len) return 1; - read_lock(&mrt_lock); - if (mrt->mroute_reg_vif_num >= 0) - reg_dev = vif_dev_read(&mrt->vif_table[mrt->mroute_reg_vif_num]); - read_unlock(&mrt_lock); - + /* Pairs with WRITE_ONCE() in vif_add()/vid_delete() */ + vif_num = READ_ONCE(mrt->mroute_reg_vif_num); + if (vif_num >= 0) + reg_dev = vif_dev_read(&mrt->vif_table[vif_num]); if (!reg_dev) return 1; |