diff options
| author |   Paolo Abeni <pabeni@redhat.com> | 2021-03-30 18:43:54 +0200 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2021-03-30 13:57:28 -0700 |
| commit | 9adc89af724f12a03b47099cd943ed54e877cd59 (patch) | |
| tree | 6bf5372364c7c76a17132f6df8b55ad2b1afdd9d /net/core | |
| parent | sch_htb: fix null pointer dereference on a null new_q (diff) | |
| download | linux-dev-9adc89af724f12a03b47099cd943ed54e877cd59.tar.xz linux-dev-9adc89af724f12a03b47099cd943ed54e877cd59.zip | |
net: let skb_orphan_partial wake-up waiters.
Currently the mentioned helper can end-up freeing the socket wmem
without waking-up any processes waiting for more write memory.
If the partially orphaned skb is attached to an UDP (or raw) socket,
the lack of wake-up can hang the user-space.
Even for TCP sockets not calling the sk destructor could have bad
effects on TSQ.
Address the issue using skb_orphan to release the sk wmem before
setting the new sock_efree destructor. Additionally bundle the
whole ownership update in a new helper, so that later other
potential users could avoid duplicate code.
v1 -> v2:
- use skb_orphan() instead of sort of open coding it (Eric)
- provide an helper for the ownership change (Eric)
Fixes: f6ba8d33cfbb ("netem: fix skb_orphan_partial()")
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/sock.c | 12 |
1 files changed, 3 insertions, 9 deletions
diff --git a/net/core/sock.c b/net/core/sock.c index cc31b601ae10..5ec90f99e102 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2132,16 +2132,10 @@ void skb_orphan_partial(struct sk_buff *skb) if (skb_is_tcp_pure_ack(skb)) return; - if (can_skb_orphan_partial(skb)) { - struct sock *sk = skb->sk; - - if (refcount_inc_not_zero(&sk->sk_refcnt)) { - WARN_ON(refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc)); - skb->destructor = sock_efree; - } - } else { + if (can_skb_orphan_partial(skb)) + skb_set_owner_sk_safe(skb, skb->sk); + else skb_orphan(skb); - } } EXPORT_SYMBOL(skb_orphan_partial); |