[PATCH 59/93] libceph: wrap auth methods in a mutex

From: Luis Henriques
Date: Tue Jun 18 2013 - 07:55:28 EST


3.5.7.15 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Sage Weil <sage@xxxxxxxxxxx>

commit e9966076cdd952e19f2dd4854cd719be0d7cbebc upstream.

The auth code is called from a variety of contexts, include the mon_client
(protected by the monc's mutex) and the messenger callbacks (currently
protected by nothing). Avoid chaos by protecting all auth state with a
mutex. Nothing is blocking, so this should be simple and lightweight.

Signed-off-by: Sage Weil <sage@xxxxxxxxxxx>
Reviewed-by: Alex Elder <elder@xxxxxxxxxxx>
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
---
include/linux/ceph/auth.h | 2 ++
net/ceph/auth.c | 78 ++++++++++++++++++++++++++++++++++-------------
2 files changed, 58 insertions(+), 22 deletions(-)

diff --git a/include/linux/ceph/auth.h b/include/linux/ceph/auth.h
index c9c3b3a..5f33868 100644
--- a/include/linux/ceph/auth.h
+++ b/include/linux/ceph/auth.h
@@ -78,6 +78,8 @@ struct ceph_auth_client {
u64 global_id; /* our unique id in system */
const struct ceph_crypto_key *key; /* our secret key */
unsigned want_keys; /* which services we want */
+
+ struct mutex mutex;
};

extern struct ceph_auth_client *ceph_auth_init(const char *name,
diff --git a/net/ceph/auth.c b/net/ceph/auth.c
index a22de54..6b923bc 100644
--- a/net/ceph/auth.c
+++ b/net/ceph/auth.c
@@ -47,6 +47,7 @@ struct ceph_auth_client *ceph_auth_init(const char *name, const struct ceph_cryp
if (!ac)
goto out;

+ mutex_init(&ac->mutex);
ac->negotiating = true;
if (name)
ac->name = name;
@@ -73,10 +74,12 @@ void ceph_auth_destroy(struct ceph_auth_client *ac)
*/
void ceph_auth_reset(struct ceph_auth_client *ac)
{
+ mutex_lock(&ac->mutex);
dout("auth_reset %p\n", ac);
if (ac->ops && !ac->negotiating)
ac->ops->reset(ac);
ac->negotiating = true;
+ mutex_unlock(&ac->mutex);
}

int ceph_entity_name_encode(const char *name, void **p, void *end)
@@ -102,6 +105,7 @@ int ceph_auth_build_hello(struct ceph_auth_client *ac, void *buf, size_t len)
int i, num;
int ret;

+ mutex_lock(&ac->mutex);
dout("auth_build_hello\n");
monhdr->have_version = 0;
monhdr->session_mon = cpu_to_le16(-1);
@@ -122,15 +126,19 @@ int ceph_auth_build_hello(struct ceph_auth_client *ac, void *buf, size_t len)

ret = ceph_entity_name_encode(ac->name, &p, end);
if (ret < 0)
- return ret;
+ goto out;
ceph_decode_need(&p, end, sizeof(u64), bad);
ceph_encode_64(&p, ac->global_id);

ceph_encode_32(&lenp, p - lenp - sizeof(u32));
- return p - buf;
+ ret = p - buf;
+out:
+ mutex_unlock(&ac->mutex);
+ return ret;

bad:
- return -ERANGE;
+ ret = -ERANGE;
+ goto out;
}

static int ceph_build_auth_request(struct ceph_auth_client *ac,
@@ -151,11 +159,13 @@ static int ceph_build_auth_request(struct ceph_auth_client *ac,
if (ret < 0) {
pr_err("error %d building auth method %s request\n", ret,
ac->ops->name);
- return ret;
+ goto out;
}
dout(" built request %d bytes\n", ret);
ceph_encode_32(&p, ret);
- return p + ret - msg_buf;
+ ret = p + ret - msg_buf;
+out:
+ return ret;
}

/*
@@ -176,6 +186,7 @@ int ceph_handle_auth_reply(struct ceph_auth_client *ac,
int result_msg_len;
int ret = -EINVAL;

+ mutex_lock(&ac->mutex);
dout("handle_auth_reply %p %p\n", p, end);
ceph_decode_need(&p, end, sizeof(u32) * 3 + sizeof(u64), bad);
protocol = ceph_decode_32(&p);
@@ -227,35 +238,44 @@ int ceph_handle_auth_reply(struct ceph_auth_client *ac,

ret = ac->ops->handle_reply(ac, result, payload, payload_end);
if (ret == -EAGAIN) {
- return ceph_build_auth_request(ac, reply_buf, reply_len);
+ ret = ceph_build_auth_request(ac, reply_buf, reply_len);
} else if (ret) {
pr_err("auth method '%s' error %d\n", ac->ops->name, ret);
- return ret;
}
- return 0;

-bad:
- pr_err("failed to decode auth msg\n");
out:
+ mutex_unlock(&ac->mutex);
return ret;
+
+bad:
+ pr_err("failed to decode auth msg\n");
+ ret = -EINVAL;
+ goto out;
}

int ceph_build_auth(struct ceph_auth_client *ac,
void *msg_buf, size_t msg_len)
{
+ int ret = 0;
+
+ mutex_lock(&ac->mutex);
if (!ac->protocol)
- return ceph_auth_build_hello(ac, msg_buf, msg_len);
- BUG_ON(!ac->ops);
- if (ac->ops->should_authenticate(ac))
- return ceph_build_auth_request(ac, msg_buf, msg_len);
- return 0;
+ ret = ceph_auth_build_hello(ac, msg_buf, msg_len);
+ else if (ac->ops->should_authenticate(ac))
+ ret = ceph_build_auth_request(ac, msg_buf, msg_len);
+ mutex_unlock(&ac->mutex);
+ return ret;
}

int ceph_auth_is_authenticated(struct ceph_auth_client *ac)
{
- if (!ac->ops)
- return 0;
- return ac->ops->is_authenticated(ac);
+ int ret = 0;
+
+ mutex_lock(&ac->mutex);
+ if (ac->ops)
+ ret = ac->ops->is_authenticated(ac);
+ mutex_unlock(&ac->mutex);
+ return ret;
}
EXPORT_SYMBOL(ceph_auth_is_authenticated);

@@ -263,17 +283,23 @@ int ceph_auth_create_authorizer(struct ceph_auth_client *ac,
int peer_type,
struct ceph_auth_handshake *auth)
{
+ int ret = 0;
+
+ mutex_lock(&ac->mutex);
if (ac->ops && ac->ops->create_authorizer)
- return ac->ops->create_authorizer(ac, peer_type, auth);
- return 0;
+ ret = ac->ops->create_authorizer(ac, peer_type, auth);
+ mutex_unlock(&ac->mutex);
+ return ret;
}
EXPORT_SYMBOL(ceph_auth_create_authorizer);

void ceph_auth_destroy_authorizer(struct ceph_auth_client *ac,
struct ceph_authorizer *a)
{
+ mutex_lock(&ac->mutex);
if (ac->ops && ac->ops->destroy_authorizer)
ac->ops->destroy_authorizer(ac, a);
+ mutex_unlock(&ac->mutex);
}
EXPORT_SYMBOL(ceph_auth_destroy_authorizer);

@@ -283,8 +309,10 @@ int ceph_auth_update_authorizer(struct ceph_auth_client *ac,
{
int ret = 0;

+ mutex_lock(&ac->mutex);
if (ac->ops && ac->ops->update_authorizer)
ret = ac->ops->update_authorizer(ac, peer_type, a);
+ mutex_unlock(&ac->mutex);
return ret;
}
EXPORT_SYMBOL(ceph_auth_update_authorizer);
@@ -292,15 +320,21 @@ EXPORT_SYMBOL(ceph_auth_update_authorizer);
int ceph_auth_verify_authorizer_reply(struct ceph_auth_client *ac,
struct ceph_authorizer *a, size_t len)
{
+ int ret = 0;
+
+ mutex_lock(&ac->mutex);
if (ac->ops && ac->ops->verify_authorizer_reply)
- return ac->ops->verify_authorizer_reply(ac, a, len);
- return 0;
+ ret = ac->ops->verify_authorizer_reply(ac, a, len);
+ mutex_unlock(&ac->mutex);
+ return ret;
}
EXPORT_SYMBOL(ceph_auth_verify_authorizer_reply);

void ceph_auth_invalidate_authorizer(struct ceph_auth_client *ac, int peer_type)
{
+ mutex_lock(&ac->mutex);
if (ac->ops && ac->ops->invalidate_authorizer)
ac->ops->invalidate_authorizer(ac, peer_type);
+ mutex_unlock(&ac->mutex);
}
EXPORT_SYMBOL(ceph_auth_invalidate_authorizer);
--
1.8.1.2

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