diff mbox

[5/6] libceph: wrap auth methods in a mutex

Message ID 1363734486-26879-5-git-send-email-sage@inktank.com (mailing list archive)
State New, archived
Headers show

Commit Message

Sage Weil March 19, 2013, 11:08 p.m. UTC
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@inktank.com>
---
 include/linux/ceph/auth.h |    2 ++
 net/ceph/auth.c           |   78 ++++++++++++++++++++++++++++++++-------------
 2 files changed, 58 insertions(+), 22 deletions(-)

Comments

Alex Elder March 25, 2013, 2:32 p.m. UTC | #1
On 03/19/2013 06:08 PM, Sage Weil wrote:
> 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@inktank.com>

This looks good, but there are some cleanups that should have gone
into the previous patch that I suggest below.

Reviewed-by: Alex Elder <elder@inktank.com>

> ---
>  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);

I suggest creating ceph_auth_handle_reply() in the previous patch,
and then use it here.

>  	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))

Same basic suggestion here, create ceph_auth_should_authenticate()
in the previous patch and use it here.

> -		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);

And ceph_auth_is_authenticated() here...

> +	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);

This should have been switched to use the helper in the previous patch.

> -	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)

And this too.

>  		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);

And here, and so on.  (Done making this comment.)

> +	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);
> 

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Sage Weil March 25, 2013, 4:26 p.m. UTC | #2
On Mon, 25 Mar 2013, Alex Elder wrote:
> On 03/19/2013 06:08 PM, Sage Weil wrote:
> > 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@inktank.com>
> 
> This looks good, but there are some cleanups that should have gone
> into the previous patch that I suggest below.
> 
> Reviewed-by: Alex Elder <elder@inktank.com>
> 
> > ---
> >  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);
> 
> I suggest creating ceph_auth_handle_reply() in the previous patch,
> and then use it here.

This one is an internal op that is not used outside of auth.c, and its 
required.

> 
> >  	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))
> 
> Same basic suggestion here, create ceph_auth_should_authenticate()
> in the previous patch and use it here.

Ditto

> 
> > -		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);
> 
> And ceph_auth_is_authenticated() here...

These *are* the wrappers :)


> 
> > +	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);
> 
> This should have been switched to use the helper in the previous patch.
> 
> > -	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)
> 
> And this too.
> 
> >  		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);
> 
> And here, and so on.  (Done making this comment.)
> 
> > +	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);
> > 
> 
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> 
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Alex Elder March 25, 2013, 4:49 p.m. UTC | #3
On 03/25/2013 11:26 AM, Sage Weil wrote:
>> > And ceph_auth_is_authenticated() here...
> These *are* the wrappers :)

D'oh!

Good thing I quit commenting on those then.

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diff mbox

Patch

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);