diff options
| author | Marcel Holtmann <marcel@holtmann.org> | 2006-10-15 17:31:14 +0200 |
|---|---|---|
| committer | David S. Miller <davem@sunset.davemloft.net> | 2006-10-15 23:14:34 -0700 |
| commit | 74da626a1098640ddc40c0e3481c0cd41e8ec1e9 (patch) | |
| tree | 65e6f72f07c0cccbb37b3b079d93276b061d9ade /net/bluetooth/af_bluetooth.c | |
| parent | cb19d9ea2ce2bcbe291d3d48e3501dc4f33ba627 (diff) | |
| download | lwn-74da626a1098640ddc40c0e3481c0cd41e8ec1e9.tar.gz lwn-74da626a1098640ddc40c0e3481c0cd41e8ec1e9.zip | |
[Bluetooth] Add locking for bt_proto array manipulation
The bt_proto array needs to be protected by some kind of locking to
prevent a race condition between bt_sock_create and bt_sock_register.
And in addition all calls to sk_alloc need to be made GFP_ATOMIC now.
Signed-off-by: Masatake YAMATO <jet@gyve.org>
Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Diffstat (limited to 'net/bluetooth/af_bluetooth.c')
| -rw-r--r-- | net/bluetooth/af_bluetooth.c | 36 |
1 files changed, 29 insertions, 7 deletions
diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c index a91fee4f2705..67df99e2e5c8 100644 --- a/net/bluetooth/af_bluetooth.c +++ b/net/bluetooth/af_bluetooth.c @@ -53,36 +53,51 @@ /* Bluetooth sockets */ #define BT_MAX_PROTO 8 static struct net_proto_family *bt_proto[BT_MAX_PROTO]; +static DEFINE_RWLOCK(bt_proto_lock); int bt_sock_register(int proto, struct net_proto_family *ops) { + int err = 0; + if (proto < 0 || proto >= BT_MAX_PROTO) return -EINVAL; + write_lock(&bt_proto_lock); + if (bt_proto[proto]) - return -EEXIST; + err = -EEXIST; + else + bt_proto[proto] = ops; - bt_proto[proto] = ops; - return 0; + write_unlock(&bt_proto_lock); + + return err; } EXPORT_SYMBOL(bt_sock_register); int bt_sock_unregister(int proto) { + int err = 0; + if (proto < 0 || proto >= BT_MAX_PROTO) return -EINVAL; + write_lock(&bt_proto_lock); + if (!bt_proto[proto]) - return -ENOENT; + err = -ENOENT; + else + bt_proto[proto] = NULL; - bt_proto[proto] = NULL; - return 0; + write_unlock(&bt_proto_lock); + + return err; } EXPORT_SYMBOL(bt_sock_unregister); static int bt_sock_create(struct socket *sock, int proto) { - int err = 0; + int err; if (proto < 0 || proto >= BT_MAX_PROTO) return -EINVAL; @@ -92,11 +107,18 @@ static int bt_sock_create(struct socket *sock, int proto) request_module("bt-proto-%d", proto); } #endif + err = -EPROTONOSUPPORT; + + read_lock(&bt_proto_lock); + if (bt_proto[proto] && try_module_get(bt_proto[proto]->owner)) { err = bt_proto[proto]->create(sock, proto); module_put(bt_proto[proto]->owner); } + + read_unlock(&bt_proto_lock); + return err; } |