diff options
| author | David Howells <dhowells@redhat.com> | 2018-03-30 21:05:23 +0100 |
|---|---|---|
| committer | David Howells <dhowells@redhat.com> | 2018-03-30 21:05:23 +0100 |
| commit | d3be4d244330f7ef53242d8dc1b7f77d105e767f (patch) | |
| tree | 794c9aeba90ac11e8d6a3109df89ad966adc73f6 /net/rxrpc/ar-internal.h | |
| parent | 88f2a8257c9aa7df957b1a79a104f348d60d8027 (diff) | |
rxrpc: Fix potential call vs socket/net destruction race
rxrpc_call structs don't pin sockets or network namespaces, but may attempt
to access both after their refcount reaches 0 so that they can detach
themselves from the network namespace. However, there's no guarantee that
the socket still exists at this point (so sock_net(&call->socket->sk) may
be invalid) and the namespace may have gone away if the call isn't pinning
a peer.
Fix this by (a) carrying a net pointer in the rxrpc_call struct and (b)
waiting for all calls to be destroyed when the network namespace goes away.
This was detected by checker:
net/rxrpc/call_object.c:634:57: warning: incorrect type in argument 1 (different address spaces)
net/rxrpc/call_object.c:634:57: expected struct sock const *sk
net/rxrpc/call_object.c:634:57: got struct sock [noderef] <asn:4>*<noident>
Fixes: 2baec2c3f854 ("rxrpc: Support network namespacing")
Signed-off-by: David Howells <dhowells@redhat.com>
Diffstat (limited to 'net/rxrpc/ar-internal.h')
| -rw-r--r-- | net/rxrpc/ar-internal.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h index 8a348e0a9d95..2a2b0fdfb157 100644 --- a/net/rxrpc/ar-internal.h +++ b/net/rxrpc/ar-internal.h @@ -75,6 +75,7 @@ struct rxrpc_net { u32 epoch; /* Local epoch for detecting local-end reset */ struct list_head calls; /* List of calls active in this namespace */ rwlock_t call_lock; /* Lock for ->calls */ + atomic_t nr_calls; /* Count of allocated calls */ struct list_head conn_proc_list; /* List of conns in this namespace for proc */ struct list_head service_conns; /* Service conns in this namespace */ @@ -528,6 +529,7 @@ struct rxrpc_call { struct rxrpc_connection *conn; /* connection carrying call */ struct rxrpc_peer *peer; /* Peer record for remote address */ struct rxrpc_sock __rcu *socket; /* socket responsible */ + struct rxrpc_net *rxnet; /* Network namespace to which call belongs */ struct mutex user_mutex; /* User access mutex */ unsigned long ack_at; /* When deferred ACK needs to happen */ unsigned long ack_lost_at; /* When ACK is figured as lost */ |