[PATCH 0/7] keys: Add tracepoints

[PATCH 0/7] keys: Add tracepoints

[David Howells]

Hi Jarkko,

Here's a patch to add some tracepoints to keyrings to make it easier to
debug what's going on, plus a bunch of preliminary patches to move things
about a bit to make that easier.

The patches can also be found here:

	https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/log/?h=keys-next

Thanks,
David

David Howells (7):
  keys: Out of line key_is_dead() so it can have tracepoints added in
  keys: Extract struct key_user to its own header for tracing purposes
  keys: Move key_get() out of line so a tracepoint can be added
  keys: Add a key_ref_get() wrapper
  keys: Use key_get() instead of __key_get()
  keys: Provide a key_try_get() function and use it
  keys: Add tracepoints for the keyrings facility

 Documentation/security/keys/core.rst |   1 -
 crypto/asymmetric_keys/restrict.c    |   6 +-
 include/keys/key_user.h              |  35 +++
 include/linux/key.h                  |  16 +-
 include/trace/events/key.h           | 401 +++++++++++++++++++++++++++
 security/keys/gc.c                   |   4 +
 security/keys/internal.h             |  41 +--
 security/keys/key.c                  |  70 ++++-
 security/keys/keyctl.c               |   2 +
 security/keys/keyring.c              |  45 ++-
 security/keys/process_keys.c         |  15 +-
 11 files changed, 566 insertions(+), 70 deletions(-)
 create mode 100644 include/keys/key_user.h
 create mode 100644 include/trace/events/key.h

[PATCH 1/7] keys: Out of line key_is_dead() so it can have tracepoints added in

[David Howells]

Move key_is_dead() out of line so that tracepoints can be added in to it
without incurring circular #includes.  Also, it is only used from the file
it is moved into.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jarkko Sakkinen <jarkko@kernel.org>
cc: keyrings@vger.kernel.org
cc: linux-security-module@vger.kernel.org
---
 security/keys/internal.h | 20 --------------------
 security/keys/keyring.c  | 20 ++++++++++++++++++++
 2 files changed, 20 insertions(+), 20 deletions(-)

diff --git a/security/keys/internal.h b/security/keys/internal.h
index 2cffa6dc8255..8ba87127e446 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -211,26 +211,6 @@ extern struct key *request_key_auth_new(struct key *target,
 
 extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
 
-/*
- * Determine whether a key is dead.
- */
-static inline bool key_is_dead(const struct key *key, time64_t limit)
-{
-	time64_t expiry = key->expiry;
-
-	if (expiry != TIME64_MAX) {
-		if (!(key->type->flags & KEY_TYPE_INSTANT_REAP))
-			expiry += key_gc_delay;
-		if (expiry <= limit)
-			return true;
-	}
-
-	return
-		key->flags & ((1 << KEY_FLAG_DEAD) |
-			      (1 << KEY_FLAG_INVALIDATED)) ||
-		key->domain_tag->removed;
-}
-
 /*
  * keyctl() functions
  */
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index 4448758f643a..0eed018448cb 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -1687,6 +1687,26 @@ static void keyring_revoke(struct key *keyring)
 	}
 }
 
+/*
+ * Determine whether a key is dead.
+ */
+static bool key_is_dead(const struct key *key, time64_t limit)
+{
+	time64_t expiry = key->expiry;
+
+	if (expiry != TIME64_MAX) {
+		if (!(key->type->flags & KEY_TYPE_INSTANT_REAP))
+			expiry += key_gc_delay;
+		if (expiry <= limit)
+			return true;
+	}
+
+	return
+		key->flags & ((1 << KEY_FLAG_DEAD) |
+			      (1 << KEY_FLAG_INVALIDATED)) ||
+		key->domain_tag->removed;
+}
+
 static bool keyring_gc_select_iterator(void *object, void *iterator_data)
 {
 	struct key *key = keyring_ptr_to_key(object);

Re: [PATCH 1/7] keys: Out of line key_is_dead() so it can have tracepoints added in

[Jarkko Sakkinen]

On Wed Aug 21, 2024 at 3:36 PM EEST, David Howells wrote:
> Move key_is_dead() out of line so that tracepoints can be added in to it
> without incurring circular #includes.  Also, it is only used from the file
> it is moved into.
>
> Signed-off-by: David Howells <dhowells@redhat.com>
> cc: Jarkko Sakkinen <jarkko@kernel.org>
> cc: keyrings@vger.kernel.org
> cc: linux-security-module@vger.kernel.org
> ---
>  security/keys/internal.h | 20 --------------------
>  security/keys/keyring.c  | 20 ++++++++++++++++++++
>  2 files changed, 20 insertions(+), 20 deletions(-)
>
> diff --git a/security/keys/internal.h b/security/keys/internal.h
> index 2cffa6dc8255..8ba87127e446 100644
> --- a/security/keys/internal.h
> +++ b/security/keys/internal.h
> @@ -211,26 +211,6 @@ extern struct key *request_key_auth_new(struct key *target,
>  
>  extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
>  
> -/*
> - * Determine whether a key is dead.
> - */
> -static inline bool key_is_dead(const struct key *key, time64_t limit)
> -{
> -	time64_t expiry = key->expiry;
> -
> -	if (expiry != TIME64_MAX) {
> -		if (!(key->type->flags & KEY_TYPE_INSTANT_REAP))
> -			expiry += key_gc_delay;
> -		if (expiry <= limit)
> -			return true;
> -	}
> -
> -	return
> -		key->flags & ((1 << KEY_FLAG_DEAD) |
> -			      (1 << KEY_FLAG_INVALIDATED)) ||
> -		key->domain_tag->removed;
> -}
> -
>  /*
>   * keyctl() functions
>   */
> diff --git a/security/keys/keyring.c b/security/keys/keyring.c
> index 4448758f643a..0eed018448cb 100644
> --- a/security/keys/keyring.c
> +++ b/security/keys/keyring.c
> @@ -1687,6 +1687,26 @@ static void keyring_revoke(struct key *keyring)
>  	}
>  }
>  
> +/*
> + * Determine whether a key is dead.
> + */
> +static bool key_is_dead(const struct key *key, time64_t limit)
> +{
> +	time64_t expiry = key->expiry;
> +
> +	if (expiry != TIME64_MAX) {
> +		if (!(key->type->flags & KEY_TYPE_INSTANT_REAP))
> +			expiry += key_gc_delay;
> +		if (expiry <= limit)
> +			return true;
> +	}
> +
> +	return
> +		key->flags & ((1 << KEY_FLAG_DEAD) |
> +			      (1 << KEY_FLAG_INVALIDATED)) ||
> +		key->domain_tag->removed;
> +}
> +
>  static bool keyring_gc_select_iterator(void *object, void *iterator_data)
>  {
>  	struct key *key = keyring_ptr_to_key(object);

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>

BR, Jarkko

[PATCH 2/7] keys: Extract struct key_user to its own header for tracing purposes

[David Howells]

Extract the key_user struct  to its own header file to make it easier to
access from tracepoints.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jarkko Sakkinen <jarkko@kernel.org>
cc: keyrings@vger.kernel.org
cc: linux-security-module@vger.kernel.org
---
 include/keys/key_user.h  | 35 +++++++++++++++++++++++++++++++++++
 security/keys/internal.h | 20 +-------------------
 2 files changed, 36 insertions(+), 19 deletions(-)
 create mode 100644 include/keys/key_user.h

diff --git a/include/keys/key_user.h b/include/keys/key_user.h
new file mode 100644
index 000000000000..e9c383d8116e
--- /dev/null
+++ b/include/keys/key_user.h
@@ -0,0 +1,35 @@
+/* User quota tracking for keys.
+ *
+ * Copyright (C) 2024 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#ifndef _KEYS_KEY_USER_H
+#define _KEYS_KEY_USER_H
+
+/*
+ * Keep track of keys for a user.
+ *
+ * This needs to be separate to user_struct to avoid a refcount-loop
+ * (user_struct pins some keyrings which pin this struct).
+ *
+ * We also keep track of keys under request from userspace for this UID here.
+ */
+struct key_user {
+	struct rb_node		node;
+	struct mutex		cons_lock;	/* construction initiation lock */
+	spinlock_t		lock;
+	refcount_t		usage;		/* for accessing qnkeys & qnbytes */
+	atomic_t		nkeys;		/* number of keys */
+	atomic_t		nikeys;		/* number of instantiated keys */
+	kuid_t			uid;
+	int			qnkeys;		/* number of keys allocated to this user */
+	int			qnbytes;	/* number of bytes allocated to this user */
+};
+
+#endif /* _KEYS_KEY_USER_H */
diff --git a/security/keys/internal.h b/security/keys/internal.h
index 8ba87127e446..33c929a6bb97 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -19,6 +19,7 @@
 #include <linux/compat.h>
 #include <linux/mm.h>
 #include <linux/vmalloc.h>
+#include <keys/key_user.h>
 
 struct iovec;
 
@@ -43,25 +44,6 @@ extern struct key_type key_type_user;
 extern struct key_type key_type_logon;
 
 /*****************************************************************************/
-/*
- * Keep track of keys for a user.
- *
- * This needs to be separate to user_struct to avoid a refcount-loop
- * (user_struct pins some keyrings which pin this struct).
- *
- * We also keep track of keys under request from userspace for this UID here.
- */
-struct key_user {
-	struct rb_node		node;
-	struct mutex		cons_lock;	/* construction initiation lock */
-	spinlock_t		lock;
-	refcount_t		usage;		/* for accessing qnkeys & qnbytes */
-	atomic_t		nkeys;		/* number of keys */
-	atomic_t		nikeys;		/* number of instantiated keys */
-	kuid_t			uid;
-	int			qnkeys;		/* number of keys allocated to this user */
-	int			qnbytes;	/* number of bytes allocated to this user */
-};
 
 extern struct rb_root	key_user_tree;
 extern spinlock_t	key_user_lock;

Re: [PATCH 2/7] keys: Extract struct key_user to its own header for tracing purposes

[Jarkko Sakkinen]

On Wed Aug 21, 2024 at 3:36 PM EEST, David Howells wrote:
> Extract the key_user struct  to its own header file to make it easier to
> access from tracepoints.
>
> Signed-off-by: David Howells <dhowells@redhat.com>
> cc: Jarkko Sakkinen <jarkko@kernel.org>
> cc: keyrings@vger.kernel.org
> cc: linux-security-module@vger.kernel.org
> ---
>  include/keys/key_user.h  | 35 +++++++++++++++++++++++++++++++++++
>  security/keys/internal.h | 20 +-------------------
>  2 files changed, 36 insertions(+), 19 deletions(-)
>  create mode 100644 include/keys/key_user.h
>
> diff --git a/include/keys/key_user.h b/include/keys/key_user.h
> new file mode 100644
> index 000000000000..e9c383d8116e
> --- /dev/null
> +++ b/include/keys/key_user.h
> @@ -0,0 +1,35 @@
> +/* User quota tracking for keys.
> + *
> + * Copyright (C) 2024 Red Hat, Inc. All Rights Reserved.
> + * Written by David Howells (dhowells@redhat.com)
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public Licence
> + * as published by the Free Software Foundation; either version
> + * 2 of the Licence, or (at your option) any later version.
> + */
> +
> +#ifndef _KEYS_KEY_USER_H
> +#define _KEYS_KEY_USER_H
> +
> +/*
> + * Keep track of keys for a user.
> + *
> + * This needs to be separate to user_struct to avoid a refcount-loop
> + * (user_struct pins some keyrings which pin this struct).
> + *
> + * We also keep track of keys under request from userspace for this UID here.
> + */
> +struct key_user {
> +	struct rb_node		node;
> +	struct mutex		cons_lock;	/* construction initiation lock */
> +	spinlock_t		lock;
> +	refcount_t		usage;		/* for accessing qnkeys & qnbytes */
> +	atomic_t		nkeys;		/* number of keys */
> +	atomic_t		nikeys;		/* number of instantiated keys */
> +	kuid_t			uid;
> +	int			qnkeys;		/* number of keys allocated to this user */
> +	int			qnbytes;	/* number of bytes allocated to this user */
> +};
> +
> +#endif /* _KEYS_KEY_USER_H */
> diff --git a/security/keys/internal.h b/security/keys/internal.h
> index 8ba87127e446..33c929a6bb97 100644
> --- a/security/keys/internal.h
> +++ b/security/keys/internal.h
> @@ -19,6 +19,7 @@
>  #include <linux/compat.h>
>  #include <linux/mm.h>
>  #include <linux/vmalloc.h>
> +#include <keys/key_user.h>
>  
>  struct iovec;
>  
> @@ -43,25 +44,6 @@ extern struct key_type key_type_user;
>  extern struct key_type key_type_logon;
>  
>  /*****************************************************************************/
> -/*
> - * Keep track of keys for a user.
> - *
> - * This needs to be separate to user_struct to avoid a refcount-loop
> - * (user_struct pins some keyrings which pin this struct).
> - *
> - * We also keep track of keys under request from userspace for this UID here.
> - */
> -struct key_user {
> -	struct rb_node		node;
> -	struct mutex		cons_lock;	/* construction initiation lock */
> -	spinlock_t		lock;
> -	refcount_t		usage;		/* for accessing qnkeys & qnbytes */
> -	atomic_t		nkeys;		/* number of keys */
> -	atomic_t		nikeys;		/* number of instantiated keys */
> -	kuid_t			uid;
> -	int			qnkeys;		/* number of keys allocated to this user */
> -	int			qnbytes;	/* number of bytes allocated to this user */
> -};
>  
>  extern struct rb_root	key_user_tree;
>  extern spinlock_t	key_user_lock;


Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>


BR, Jarkko

[PATCH 3/7] keys: Move key_get() out of line so a tracepoint can be added

[David Howells]

Move key_get() out of line so that a tracepoint can be added into it
without incurring circular header dependencies or overly expanding the
callers.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jarkko Sakkinen <jarkko@kernel.org>
cc: keyrings@vger.kernel.org
cc: linux-security-module@vger.kernel.org
---
 include/linux/key.h |  6 +-----
 security/keys/key.c | 14 ++++++++++++++
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/include/linux/key.h b/include/linux/key.h
index 943a432da3ae..08062b4f807c 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -299,6 +299,7 @@ extern struct key *key_alloc(struct key_type *type,
 
 extern void key_revoke(struct key *key);
 extern void key_invalidate(struct key *key);
+struct key *key_get(struct key *key);
 extern void key_put(struct key *key);
 extern bool key_put_tag(struct key_tag *tag);
 extern void key_remove_domain(struct key_tag *domain_tag);
@@ -309,11 +310,6 @@ static inline struct key *__key_get(struct key *key)
 	return key;
 }
 
-static inline struct key *key_get(struct key *key)
-{
-	return key ? __key_get(key) : key;
-}
-
 static inline void key_ref_put(key_ref_t key_ref)
 {
 	key_put(key_ref_to_ptr(key_ref));
diff --git a/security/keys/key.c b/security/keys/key.c
index 3d7d185019d3..14c7ee77ea15 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -635,6 +635,20 @@ int key_reject_and_link(struct key *key,
 }
 EXPORT_SYMBOL(key_reject_and_link);
 
+/**
+ * key_get - Get a reference on a key
+ * @key: The key to get a reference on.
+ *
+ * Get a reference on a key, if not NULL, and return the parameter.
+ */
+struct key *key_get(struct key *key)
+{
+	if (key)
+		refcount_inc(&key->usage);
+	return key;
+}
+EXPORT_SYMBOL(key_get);
+
 /**
  * key_put - Discard a reference to a key.
  * @key: The key to discard a reference from.

Re: [PATCH 3/7] keys: Move key_get() out of line so a tracepoint can be added

[Jarkko Sakkinen]

On Wed Aug 21, 2024 at 3:36 PM EEST, David Howells wrote:
> Move key_get() out of line so that a tracepoint can be added into it
> without incurring circular header dependencies or overly expanding the
> callers.
>
> Signed-off-by: David Howells <dhowells@redhat.com>
> cc: Jarkko Sakkinen <jarkko@kernel.org>
> cc: keyrings@vger.kernel.org
> cc: linux-security-module@vger.kernel.org
> ---
>  include/linux/key.h |  6 +-----
>  security/keys/key.c | 14 ++++++++++++++
>  2 files changed, 15 insertions(+), 5 deletions(-)
>
> diff --git a/include/linux/key.h b/include/linux/key.h
> index 943a432da3ae..08062b4f807c 100644
> --- a/include/linux/key.h
> +++ b/include/linux/key.h
> @@ -299,6 +299,7 @@ extern struct key *key_alloc(struct key_type *type,
>  
>  extern void key_revoke(struct key *key);
>  extern void key_invalidate(struct key *key);
> +struct key *key_get(struct key *key);
>  extern void key_put(struct key *key);
>  extern bool key_put_tag(struct key_tag *tag);
>  extern void key_remove_domain(struct key_tag *domain_tag);
> @@ -309,11 +310,6 @@ static inline struct key *__key_get(struct key *key)
>  	return key;
>  }
>  
> -static inline struct key *key_get(struct key *key)
> -{
> -	return key ? __key_get(key) : key;
> -}
> -
>  static inline void key_ref_put(key_ref_t key_ref)
>  {
>  	key_put(key_ref_to_ptr(key_ref));
> diff --git a/security/keys/key.c b/security/keys/key.c
> index 3d7d185019d3..14c7ee77ea15 100644
> --- a/security/keys/key.c
> +++ b/security/keys/key.c
> @@ -635,6 +635,20 @@ int key_reject_and_link(struct key *key,
>  }
>  EXPORT_SYMBOL(key_reject_and_link);
>  
> +/**
> + * key_get - Get a reference on a key
> + * @key: The key to get a reference on.
> + *
> + * Get a reference on a key, if not NULL, and return the parameter.
> + */
> +struct key *key_get(struct key *key)
> +{
> +	if (key)
> +		refcount_inc(&key->usage);
> +	return key;
> +}
> +EXPORT_SYMBOL(key_get);
> +
>  /**
>   * key_put - Discard a reference to a key.
>   * @key: The key to discard a reference from.


Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>

BR, Jarkko

[PATCH 4/7] keys: Add a key_ref_get() wrapper

[David Howells]

Add a key_ref_get() wrapper function to go with key_ref_put() and use it
for the place that needs it.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jarkko Sakkinen <jarkko@kernel.org>
cc: keyrings@vger.kernel.org
cc: linux-security-module@vger.kernel.org
---
 include/linux/key.h     | 5 +++++
 security/keys/keyring.c | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/include/linux/key.h b/include/linux/key.h
index 08062b4f807c..50a19e5f9e45 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -315,6 +315,11 @@ static inline void key_ref_put(key_ref_t key_ref)
 	key_put(key_ref_to_ptr(key_ref));
 }
 
+static inline void key_ref_get(key_ref_t key_ref)
+{
+	key_get(key_ref_to_ptr(key_ref));
+}
+
 extern struct key *request_key_tag(struct key_type *type,
 				   const char *description,
 				   struct key_tag *domain_tag,
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index 0eed018448cb..7f02b913c560 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -920,7 +920,7 @@ key_ref_t keyring_search_rcu(key_ref_t keyring_ref,
 
 	ctx->now = ktime_get_real_seconds();
 	if (search_nested_keyrings(keyring, ctx))
-		__key_get(key_ref_to_ptr(ctx->result));
+		key_ref_get(ctx->result);
 	return ctx->result;
 }
 

Re: [PATCH 4/7] keys: Add a key_ref_get() wrapper

[Jarkko Sakkinen]

On Wed Aug 21, 2024 at 3:36 PM EEST, David Howells wrote:
> Add a key_ref_get() wrapper function to go with key_ref_put() and use it
> for the place that needs it.
>
> Signed-off-by: David Howells <dhowells@redhat.com>
> cc: Jarkko Sakkinen <jarkko@kernel.org>
> cc: keyrings@vger.kernel.org
> cc: linux-security-module@vger.kernel.org
> ---
>  include/linux/key.h     | 5 +++++
>  security/keys/keyring.c | 2 +-
>  2 files changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/include/linux/key.h b/include/linux/key.h
> index 08062b4f807c..50a19e5f9e45 100644
> --- a/include/linux/key.h
> +++ b/include/linux/key.h
> @@ -315,6 +315,11 @@ static inline void key_ref_put(key_ref_t key_ref)
>  	key_put(key_ref_to_ptr(key_ref));
>  }
>  
> +static inline void key_ref_get(key_ref_t key_ref)
> +{
> +	key_get(key_ref_to_ptr(key_ref));
> +}
> +
>  extern struct key *request_key_tag(struct key_type *type,
>  				   const char *description,
>  				   struct key_tag *domain_tag,
> diff --git a/security/keys/keyring.c b/security/keys/keyring.c
> index 0eed018448cb..7f02b913c560 100644
> --- a/security/keys/keyring.c
> +++ b/security/keys/keyring.c
> @@ -920,7 +920,7 @@ key_ref_t keyring_search_rcu(key_ref_t keyring_ref,
>  
>  	ctx->now = ktime_get_real_seconds();
>  	if (search_nested_keyrings(keyring, ctx))
> -		__key_get(key_ref_to_ptr(ctx->result));
> +		key_ref_get(ctx->result);
>  	return ctx->result;
>  }
>  

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>

BR, Jarkko

[PATCH 5/7] keys: Use key_get() instead of __key_get()

[David Howells]

Switch users of __key_get() over to key_get() so that they benefit from the
future tracepointage thereof also and remove __key_get().

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jarkko Sakkinen <jarkko@kernel.org>
cc: keyrings@vger.kernel.org
cc: linux-security-module@vger.kernel.org
---
 Documentation/security/keys/core.rst |  1 -
 crypto/asymmetric_keys/restrict.c    |  6 +++---
 include/linux/key.h                  |  6 ------
 security/keys/keyring.c              |  4 ++--
 security/keys/process_keys.c         | 15 ++++++---------
 5 files changed, 11 insertions(+), 21 deletions(-)

diff --git a/Documentation/security/keys/core.rst b/Documentation/security/keys/core.rst
index 326b8a973828..0b179540d885 100644
--- a/Documentation/security/keys/core.rst
+++ b/Documentation/security/keys/core.rst
@@ -1217,7 +1217,6 @@ payload contents" for more information.
  *  Extra references can be made to a key by calling one of the following
     functions::
 
-	struct key *__key_get(struct key *key);
 	struct key *key_get(struct key *key);
 
     Keys so references will need to be disposed of by calling key_put() when
diff --git a/crypto/asymmetric_keys/restrict.c b/crypto/asymmetric_keys/restrict.c
index afcd4d101ac5..1ea7bfd4e5d7 100644
--- a/crypto/asymmetric_keys/restrict.c
+++ b/crypto/asymmetric_keys/restrict.c
@@ -267,20 +267,20 @@ static int key_or_keyring_common(struct key *dest_keyring,
 			if (!sig->auth_ids[0] && !sig->auth_ids[1]) {
 				if (asymmetric_key_id_same(signer_ids[2],
 							   sig->auth_ids[2]))
-					key = __key_get(trusted);
+					key = key_get(trusted);
 
 			} else if (!sig->auth_ids[0] || !sig->auth_ids[1]) {
 				const struct asymmetric_key_id *auth_id;
 
 				auth_id = sig->auth_ids[0] ?: sig->auth_ids[1];
 				if (match_either_id(signer_ids, auth_id))
-					key = __key_get(trusted);
+					key = key_get(trusted);
 
 			} else if (asymmetric_key_id_same(signer_ids[1],
 							  sig->auth_ids[1]) &&
 				   match_either_id(signer_ids,
 						   sig->auth_ids[0])) {
-				key = __key_get(trusted);
+				key = key_get(trusted);
 			}
 		} else {
 			return -EOPNOTSUPP;
diff --git a/include/linux/key.h b/include/linux/key.h
index 50a19e5f9e45..80d736813b89 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -304,12 +304,6 @@ extern void key_put(struct key *key);
 extern bool key_put_tag(struct key_tag *tag);
 extern void key_remove_domain(struct key_tag *domain_tag);
 
-static inline struct key *__key_get(struct key *key)
-{
-	refcount_inc(&key->usage);
-	return key;
-}
-
 static inline void key_ref_put(key_ref_t key_ref)
 {
 	key_put(key_ref_to_ptr(key_ref));
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index 7f02b913c560..e77d927f1d4d 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -1122,7 +1122,7 @@ key_ref_t find_key_to_update(key_ref_t keyring_ref,
 		kleave(" = NULL [x]");
 		return NULL;
 	}
-	__key_get(key);
+	key_get(key);
 	kleave(" = {%d}", key->serial);
 	return make_key_ref(key, is_key_possessed(keyring_ref));
 }
@@ -1367,7 +1367,7 @@ int __key_link_check_live_key(struct key *keyring, struct key *key)
 void __key_link(struct key *keyring, struct key *key,
 		struct assoc_array_edit **_edit)
 {
-	__key_get(key);
+	key_get(key);
 	assoc_array_insert_set_object(*_edit, keyring_key_to_ptr(key));
 	assoc_array_apply_edit(*_edit);
 	*_edit = NULL;
diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index b5d5333ab330..01291b2d0888 100644
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -333,7 +333,7 @@ int install_session_keyring_to_cred(struct cred *cred, struct key *keyring)
 		if (IS_ERR(keyring))
 			return PTR_ERR(keyring);
 	} else {
-		__key_get(keyring);
+		key_get(keyring);
 	}
 
 	/* install the keyring */
@@ -641,7 +641,7 @@ key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
 		}
 
 		key = ctx.cred->thread_keyring;
-		__key_get(key);
+		key_get(key);
 		key_ref = make_key_ref(key, 1);
 		break;
 
@@ -658,8 +658,7 @@ key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
 			goto reget_creds;
 		}
 
-		key = ctx.cred->process_keyring;
-		__key_get(key);
+		key = key_get(ctx.cred->process_keyring);
 		key_ref = make_key_ref(key, 1);
 		break;
 
@@ -688,8 +687,7 @@ key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
 			goto reget_creds;
 		}
 
-		key = ctx.cred->session_keyring;
-		__key_get(key);
+		key = key_get(ctx.cred->session_keyring);
 		key_ref = make_key_ref(key, 1);
 		break;
 
@@ -717,7 +715,7 @@ key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
 		if (!key)
 			goto error;
 
-		__key_get(key);
+		key_get(key);
 		key_ref = make_key_ref(key, 1);
 		break;
 
@@ -732,8 +730,7 @@ key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
 			key = NULL;
 		} else {
 			rka = ctx.cred->request_key_auth->payload.data[0];
-			key = rka->dest_keyring;
-			__key_get(key);
+			key = key_get(rka->dest_keyring);
 		}
 		up_read(&ctx.cred->request_key_auth->sem);
 		if (!key)

Re: [PATCH 5/7] keys: Use key_get() instead of __key_get()

[Jarkko Sakkinen]

On Wed Aug 21, 2024 at 3:36 PM EEST, David Howells wrote:
> Switch users of __key_get() over to key_get() so that they benefit from the
> future tracepointage thereof also and remove __key_get().
>
> Signed-off-by: David Howells <dhowells@redhat.com>
> cc: Jarkko Sakkinen <jarkko@kernel.org>
> cc: keyrings@vger.kernel.org
> cc: linux-security-module@vger.kernel.org
> ---
>  Documentation/security/keys/core.rst |  1 -
>  crypto/asymmetric_keys/restrict.c    |  6 +++---
>  include/linux/key.h                  |  6 ------
>  security/keys/keyring.c              |  4 ++--
>  security/keys/process_keys.c         | 15 ++++++---------
>  5 files changed, 11 insertions(+), 21 deletions(-)
>
> diff --git a/Documentation/security/keys/core.rst b/Documentation/security/keys/core.rst
> index 326b8a973828..0b179540d885 100644
> --- a/Documentation/security/keys/core.rst
> +++ b/Documentation/security/keys/core.rst
> @@ -1217,7 +1217,6 @@ payload contents" for more information.
>   *  Extra references can be made to a key by calling one of the following
>      functions::
>  
> -	struct key *__key_get(struct key *key);
>  	struct key *key_get(struct key *key);
>  
>      Keys so references will need to be disposed of by calling key_put() when
> diff --git a/crypto/asymmetric_keys/restrict.c b/crypto/asymmetric_keys/restrict.c
> index afcd4d101ac5..1ea7bfd4e5d7 100644
> --- a/crypto/asymmetric_keys/restrict.c
> +++ b/crypto/asymmetric_keys/restrict.c
> @@ -267,20 +267,20 @@ static int key_or_keyring_common(struct key *dest_keyring,
>  			if (!sig->auth_ids[0] && !sig->auth_ids[1]) {
>  				if (asymmetric_key_id_same(signer_ids[2],
>  							   sig->auth_ids[2]))
> -					key = __key_get(trusted);
> +					key = key_get(trusted);
>  
>  			} else if (!sig->auth_ids[0] || !sig->auth_ids[1]) {
>  				const struct asymmetric_key_id *auth_id;
>  
>  				auth_id = sig->auth_ids[0] ?: sig->auth_ids[1];
>  				if (match_either_id(signer_ids, auth_id))
> -					key = __key_get(trusted);
> +					key = key_get(trusted);
>  
>  			} else if (asymmetric_key_id_same(signer_ids[1],
>  							  sig->auth_ids[1]) &&
>  				   match_either_id(signer_ids,
>  						   sig->auth_ids[0])) {
> -				key = __key_get(trusted);
> +				key = key_get(trusted);
>  			}
>  		} else {
>  			return -EOPNOTSUPP;
> diff --git a/include/linux/key.h b/include/linux/key.h
> index 50a19e5f9e45..80d736813b89 100644
> --- a/include/linux/key.h
> +++ b/include/linux/key.h
> @@ -304,12 +304,6 @@ extern void key_put(struct key *key);
>  extern bool key_put_tag(struct key_tag *tag);
>  extern void key_remove_domain(struct key_tag *domain_tag);
>  
> -static inline struct key *__key_get(struct key *key)
> -{
> -	refcount_inc(&key->usage);
> -	return key;
> -}
> -
>  static inline void key_ref_put(key_ref_t key_ref)
>  {
>  	key_put(key_ref_to_ptr(key_ref));
> diff --git a/security/keys/keyring.c b/security/keys/keyring.c
> index 7f02b913c560..e77d927f1d4d 100644
> --- a/security/keys/keyring.c
> +++ b/security/keys/keyring.c
> @@ -1122,7 +1122,7 @@ key_ref_t find_key_to_update(key_ref_t keyring_ref,
>  		kleave(" = NULL [x]");
>  		return NULL;
>  	}
> -	__key_get(key);
> +	key_get(key);
>  	kleave(" = {%d}", key->serial);
>  	return make_key_ref(key, is_key_possessed(keyring_ref));
>  }
> @@ -1367,7 +1367,7 @@ int __key_link_check_live_key(struct key *keyring, struct key *key)
>  void __key_link(struct key *keyring, struct key *key,
>  		struct assoc_array_edit **_edit)
>  {
> -	__key_get(key);
> +	key_get(key);
>  	assoc_array_insert_set_object(*_edit, keyring_key_to_ptr(key));
>  	assoc_array_apply_edit(*_edit);
>  	*_edit = NULL;
> diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
> index b5d5333ab330..01291b2d0888 100644
> --- a/security/keys/process_keys.c
> +++ b/security/keys/process_keys.c
> @@ -333,7 +333,7 @@ int install_session_keyring_to_cred(struct cred *cred, struct key *keyring)
>  		if (IS_ERR(keyring))
>  			return PTR_ERR(keyring);
>  	} else {
> -		__key_get(keyring);
> +		key_get(keyring);
>  	}
>  
>  	/* install the keyring */
> @@ -641,7 +641,7 @@ key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
>  		}
>  
>  		key = ctx.cred->thread_keyring;
> -		__key_get(key);
> +		key_get(key);
>  		key_ref = make_key_ref(key, 1);
>  		break;
>  
> @@ -658,8 +658,7 @@ key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
>  			goto reget_creds;
>  		}
>  
> -		key = ctx.cred->process_keyring;
> -		__key_get(key);
> +		key = key_get(ctx.cred->process_keyring);
>  		key_ref = make_key_ref(key, 1);
>  		break;
>  
> @@ -688,8 +687,7 @@ key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
>  			goto reget_creds;
>  		}
>  
> -		key = ctx.cred->session_keyring;
> -		__key_get(key);
> +		key = key_get(ctx.cred->session_keyring);
>  		key_ref = make_key_ref(key, 1);
>  		break;
>  
> @@ -717,7 +715,7 @@ key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
>  		if (!key)
>  			goto error;
>  
> -		__key_get(key);
> +		key_get(key);
>  		key_ref = make_key_ref(key, 1);
>  		break;
>  
> @@ -732,8 +730,7 @@ key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
>  			key = NULL;
>  		} else {
>  			rka = ctx.cred->request_key_auth->payload.data[0];
> -			key = rka->dest_keyring;
> -			__key_get(key);
> +			key = key_get(rka->dest_keyring);
>  		}
>  		up_read(&ctx.cred->request_key_auth->sem);
>  		if (!key)

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>

BR, Jarkko

[PATCH 6/7] keys: Provide a key_try_get() function and use it

[David Howells]

Add a key_try_get() function to try to get a ref on a key and switch code
that's manipulating the key refcount directly to use it.  This will allow a
tracepoint to be emplaced there later.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jarkko Sakkinen <jarkko@kernel.org>
cc: keyrings@vger.kernel.org
cc: linux-security-module@vger.kernel.org
---
 include/linux/key.h     |  1 +
 security/keys/key.c     | 16 +++++++++++++++-
 security/keys/keyring.c |  2 +-
 3 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/include/linux/key.h b/include/linux/key.h
index 80d736813b89..4e5baf3e7286 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -300,6 +300,7 @@ extern struct key *key_alloc(struct key_type *type,
 extern void key_revoke(struct key *key);
 extern void key_invalidate(struct key *key);
 struct key *key_get(struct key *key);
+struct key *key_try_get(struct key *key);
 extern void key_put(struct key *key);
 extern bool key_put_tag(struct key_tag *tag);
 extern void key_remove_domain(struct key_tag *domain_tag);
diff --git a/security/keys/key.c b/security/keys/key.c
index 14c7ee77ea15..59cffb6f9b94 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -649,6 +649,20 @@ struct key *key_get(struct key *key)
 }
 EXPORT_SYMBOL(key_get);
 
+/**
+ * key_try_get - Get a ref on a key if its refcount is not non-zero.
+ * @key: The key to get a reference on.
+ *
+ * Get a reference on a key unless it has no references and return true if
+ * successful.  @key must not be NULL.
+ */
+struct key *key_try_get(struct key *key)
+{
+	if (!refcount_inc_not_zero(&key->usage))
+		return NULL;
+	return key;
+}
+
 /**
  * key_put - Discard a reference to a key.
  * @key: The key to discard a reference from.
@@ -709,7 +723,7 @@ struct key *key_lookup(key_serial_t id)
 	/* A key is allowed to be looked up only if someone still owns a
 	 * reference to it - otherwise it's awaiting the gc.
 	 */
-	if (!refcount_inc_not_zero(&key->usage))
+	if (!key_try_get(key))
 		goto not_found;
 
 error:
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index e77d927f1d4d..a09a4c2b1bcb 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -1174,7 +1174,7 @@ struct key *find_keyring_by_name(const char *name, bool uid_keyring)
 		/* we've got a match but we might end up racing with
 		 * key_cleanup() if the keyring is currently 'dead'
 		 * (ie. it has a zero usage count) */
-		if (!refcount_inc_not_zero(&keyring->usage))
+		if (!key_try_get(keyring))
 			continue;
 		keyring->last_used_at = ktime_get_real_seconds();
 		goto out;

Re: [PATCH 6/7] keys: Provide a key_try_get() function and use it

[Jarkko Sakkinen]

On Wed Aug 21, 2024 at 3:36 PM EEST, David Howells wrote:
> Add a key_try_get() function to try to get a ref on a key and switch code
> that's manipulating the key refcount directly to use it.  This will allow a
> tracepoint to be emplaced there later.
>
> Signed-off-by: David Howells <dhowells@redhat.com>
> cc: Jarkko Sakkinen <jarkko@kernel.org>
> cc: keyrings@vger.kernel.org
> cc: linux-security-module@vger.kernel.org
> ---
>  include/linux/key.h     |  1 +
>  security/keys/key.c     | 16 +++++++++++++++-
>  security/keys/keyring.c |  2 +-
>  3 files changed, 17 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/key.h b/include/linux/key.h
> index 80d736813b89..4e5baf3e7286 100644
> --- a/include/linux/key.h
> +++ b/include/linux/key.h
> @@ -300,6 +300,7 @@ extern struct key *key_alloc(struct key_type *type,
>  extern void key_revoke(struct key *key);
>  extern void key_invalidate(struct key *key);
>  struct key *key_get(struct key *key);
> +struct key *key_try_get(struct key *key);
>  extern void key_put(struct key *key);
>  extern bool key_put_tag(struct key_tag *tag);
>  extern void key_remove_domain(struct key_tag *domain_tag);
> diff --git a/security/keys/key.c b/security/keys/key.c
> index 14c7ee77ea15..59cffb6f9b94 100644
> --- a/security/keys/key.c
> +++ b/security/keys/key.c
> @@ -649,6 +649,20 @@ struct key *key_get(struct key *key)
>  }
>  EXPORT_SYMBOL(key_get);
>  
> +/**
> + * key_try_get - Get a ref on a key if its refcount is not non-zero.
> + * @key: The key to get a reference on.
> + *
> + * Get a reference on a key unless it has no references and return true if
> + * successful.  @key must not be NULL.
> + */
> +struct key *key_try_get(struct key *key)
> +{
> +	if (!refcount_inc_not_zero(&key->usage))
> +		return NULL;
> +	return key;
> +}
> +
>  /**
>   * key_put - Discard a reference to a key.
>   * @key: The key to discard a reference from.
> @@ -709,7 +723,7 @@ struct key *key_lookup(key_serial_t id)
>  	/* A key is allowed to be looked up only if someone still owns a
>  	 * reference to it - otherwise it's awaiting the gc.
>  	 */
> -	if (!refcount_inc_not_zero(&key->usage))
> +	if (!key_try_get(key))
>  		goto not_found;
>  
>  error:
> diff --git a/security/keys/keyring.c b/security/keys/keyring.c
> index e77d927f1d4d..a09a4c2b1bcb 100644
> --- a/security/keys/keyring.c
> +++ b/security/keys/keyring.c
> @@ -1174,7 +1174,7 @@ struct key *find_keyring_by_name(const char *name, bool uid_keyring)
>  		/* we've got a match but we might end up racing with
>  		 * key_cleanup() if the keyring is currently 'dead'
>  		 * (ie. it has a zero usage count) */
> -		if (!refcount_inc_not_zero(&keyring->usage))
> +		if (!key_try_get(keyring))
>  			continue;
>  		keyring->last_used_at = ktime_get_real_seconds();
>  		goto out;

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>

BR, Jarkko

[PATCH 7/7] keys: Add tracepoints for the keyrings facility

[David Howells]

Add some tracepoints to aid in debuggin the keyrings facility and
applications that use it.  A number of events and operations are traceable,
including:

  - Allocation
  - Refcounting
  - Instantiation and negative instantiation/rejection
  - Update
  - Detection of key being dead
  - Key quota changes
  - Key quota failure
  - Link, unlink and move
  - Keyring clearance
  - Revocation and invalidation
  - Garbage collection

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jarkko Sakkinen <jarkko@kernel.org>
cc: keyrings@vger.kernel.org
cc: linux-security-module@vger.kernel.org
---
 include/trace/events/key.h | 401 +++++++++++++++++++++++++++++++++++++
 security/keys/gc.c         |   4 +
 security/keys/internal.h   |   1 +
 security/keys/key.c        |  50 ++++-
 security/keys/keyctl.c     |   2 +
 security/keys/keyring.c    |  27 ++-
 6 files changed, 472 insertions(+), 13 deletions(-)
 create mode 100644 include/trace/events/key.h

diff --git a/include/trace/events/key.h b/include/trace/events/key.h
new file mode 100644
index 000000000000..b3f8c39cc0e8
--- /dev/null
+++ b/include/trace/events/key.h
@@ -0,0 +1,401 @@
+/* Keyrings tracepoints
+ *
+ * Copyright (C) 2024 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM key
+
+#if !defined(_TRACE_KEY_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_KEY_H
+
+#include <linux/tracepoint.h>
+
+struct key;
+
+/*
+ * Declare tracing information enums and their string mappings for display.
+ */
+#define key_ref_traces \
+	EM(key_trace_ref_alloc,			"ALLOC") \
+	EM(key_trace_ref_free,			"FREE ") \
+	EM(key_trace_ref_gc,			"GC   ") \
+	EM(key_trace_ref_get,			"GET  ") \
+	EM(key_trace_ref_put,			"PUT  ") \
+	E_(key_trace_ref_try_get,		"GET  ")
+
+#define key_dead_traces \
+	EM(key_trace_dead_type_removed,		"TYPR") \
+	EM(key_trace_dead_domain_removed,	"DOMR") \
+	EM(key_trace_dead_expired,		"EXPD") \
+	E_(key_trace_dead_invalidated,		"INVL")
+
+/*
+ * Generate enums for tracing information.
+ */
+#ifndef __NETFS_DECLARE_TRACE_ENUMS_ONCE_ONLY
+#define __NETFS_DECLARE_TRACE_ENUMS_ONCE_ONLY
+
+#undef EM
+#undef E_
+#define EM(a, b) a,
+#define E_(a, b) a
+
+enum key_dead_trace	{ key_dead_traces } __mode(byte);
+enum key_ref_trace	{ key_ref_traces } __mode(byte);
+
+#endif /* end __RXRPC_DECLARE_TRACE_ENUMS_ONCE_ONLY */
+
+/*
+ * Export enum symbols via userspace.
+ */
+#undef EM
+#undef E_
+#define EM(a, b) TRACE_DEFINE_ENUM(a);
+#define E_(a, b) TRACE_DEFINE_ENUM(a);
+
+key_dead_traces;
+key_ref_traces;
+
+/*
+ * Now redefine the EM() and E_() macros to map the enums to the strings that
+ * will be printed in the output.
+ */
+#undef EM
+#undef E_
+#define EM(a, b)	{ a, b },
+#define E_(a, b)	{ a, b }
+
+TRACE_EVENT(key_alloc,
+	    TP_PROTO(const struct key *key),
+
+	    TP_ARGS(key),
+
+	    TP_STRUCT__entry(
+		    __field(key_serial_t,		key)
+		    __field(uid_t,			uid)
+		    __array(char,			type, 8)
+		    __array(char,			desc, 24)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->key = key->serial;
+		    __entry->uid = from_kuid(&init_user_ns, key->uid);
+		    strncpy(__entry->type, key->type->name, sizeof(__entry->type) - 1);
+		    strncpy(__entry->desc, key->description ?: "", sizeof(__entry->desc) - 1);
+		    __entry->type[sizeof(__entry->type) - 1] = 0;
+		    __entry->desc[sizeof(__entry->desc) - 1] = 0;
+			   ),
+
+	    TP_printk("key=%08x uid=%08x t=%s d=%s",
+		      __entry->key,
+		      __entry->uid,
+		      __entry->type,
+		      __entry->desc)
+	    );
+
+TRACE_EVENT(key_ref,
+	    TP_PROTO(key_serial_t key, unsigned int ref, enum key_ref_trace trace,
+		     const void *where),
+
+	    TP_ARGS(key, ref, trace, where),
+
+	    TP_STRUCT__entry(
+		    __field(key_serial_t,		key)
+		    __field(enum key_ref_trace,		trace)
+		    __field(unsigned int,		ref)
+		    __field(const void *,		where)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->key = key;
+		    __entry->trace = trace;
+		    __entry->ref = ref;
+		    __entry->where = where;
+			   ),
+
+	    TP_printk("key=%08x %s r=%d pc=%pSR",
+		      __entry->key,
+		      __print_symbolic(__entry->trace, key_ref_traces),
+		      __entry->ref,
+		      __entry->where)
+	    );
+
+TRACE_EVENT(key_instantiate,
+	    TP_PROTO(const struct key *key, const struct key_preparsed_payload *prep),
+
+	    TP_ARGS(key, prep),
+
+	    TP_STRUCT__entry(
+		    __field(key_serial_t,	key)
+		    __field(unsigned int,	datalen)
+		    __field(unsigned int,	quotalen)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->key = key->serial;
+		    __entry->datalen = prep->datalen;
+		    __entry->quotalen = prep->quotalen;
+			   ),
+
+	    TP_printk("key=%08x dlen=%u qlen=%u",
+		      __entry->key,
+		      __entry->datalen,
+		      __entry->quotalen)
+	    );
+
+TRACE_EVENT(key_reject,
+	    TP_PROTO(const struct key *key, int error),
+
+	    TP_ARGS(key, error),
+
+	    TP_STRUCT__entry(
+		    __field(key_serial_t,	key)
+		    __field(int,		error)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->key = key->serial;
+		    __entry->error = error;
+			   ),
+
+	    TP_printk("key=%08x err=%d",
+		      __entry->key,
+		      __entry->error)
+	    );
+
+TRACE_EVENT(key_update,
+	    TP_PROTO(const struct key *key, const struct key_preparsed_payload *prep),
+
+	    TP_ARGS(key, prep),
+
+	    TP_STRUCT__entry(
+		    __field(key_serial_t,	key)
+		    __field(unsigned int,	datalen)
+		    __field(unsigned int,	quotalen)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->key = key->serial;
+		    __entry->datalen = prep->datalen;
+		    __entry->quotalen = prep->quotalen;
+			   ),
+
+	    TP_printk("key=%08x dlen=%u qlen=%u",
+		      __entry->key,
+		      __entry->datalen,
+		      __entry->quotalen)
+	    );
+
+TRACE_EVENT(key_dead,
+	    TP_PROTO(const struct key *key, enum key_dead_trace trace),
+
+	    TP_ARGS(key, trace),
+
+	    TP_STRUCT__entry(
+		    __field(key_serial_t,		key)
+		    __field(enum key_dead_trace,	trace)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->key = key->serial;
+		    __entry->trace = trace;
+			   ),
+
+	    TP_printk("key=%08x %s",
+		      __entry->key,
+		      __print_symbolic(__entry->trace, key_dead_traces))
+	    );
+
+TRACE_EVENT(key_quota,
+	    TP_PROTO(const struct key_user *user, int change_keys, int change_bytes),
+
+	    TP_ARGS(user, change_keys, change_bytes),
+
+	    TP_STRUCT__entry(
+		    __field(uid_t,		uid)
+		    __field(unsigned int,	nkeys)
+		    __field(unsigned int,	nikeys)
+		    __field(unsigned int,	qnkeys)
+		    __field(unsigned int,	qnbytes)
+		    __field(int,		change_keys)
+		    __field(int,		change_bytes)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->uid = from_kuid(&init_user_ns, user->uid);
+		    __entry->nkeys = atomic_read(&user->nkeys);
+		    __entry->nikeys = atomic_read(&user->nikeys);
+		    __entry->qnkeys = user->qnkeys;
+		    __entry->qnbytes = user->qnbytes;
+		    __entry->change_keys = change_keys;
+		    __entry->change_bytes = change_bytes;
+			   ),
+
+	    TP_printk("uid=%d nkeys=%u/%u qkeys=%u qpay=%u ckeys=%d cpay=%d",
+		      __entry->uid,
+		      __entry->nikeys, __entry->nkeys,
+		      __entry->qnkeys,
+		      __entry->qnbytes,
+		      __entry->change_keys, __entry->change_bytes)
+	    );
+
+TRACE_EVENT(key_edquot,
+	    TP_PROTO(const struct key_user *user, unsigned int maxkeys,
+		     unsigned int maxbytes, unsigned int reqbytes),
+
+	    TP_ARGS(user, maxkeys, maxbytes, reqbytes),
+
+	    TP_STRUCT__entry(
+		    __field(uid_t,		uid)
+		    __field(unsigned int,	nkeys)
+		    __field(unsigned int,	nikeys)
+		    __field(unsigned int,	qnkeys)
+		    __field(unsigned int,	qnbytes)
+		    __field(unsigned int,	maxkeys)
+		    __field(unsigned int,	maxbytes)
+		    __field(unsigned int,	reqbytes)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->uid = from_kuid(&init_user_ns, user->uid);
+		    __entry->nkeys = atomic_read(&user->nkeys);
+		    __entry->nikeys = atomic_read(&user->nikeys);
+		    __entry->qnkeys = user->qnkeys;
+		    __entry->qnbytes = user->qnbytes;
+		    __entry->maxkeys = maxkeys;
+		    __entry->maxbytes = maxbytes;
+		    __entry->reqbytes = reqbytes;
+			   ),
+
+	    TP_printk("u=%d nkeys=%u/%u qkeys=%u/%u qpay=%u/%u cpay=%u",
+		      __entry->uid,
+		      __entry->nikeys, __entry->nkeys,
+		      __entry->qnkeys, __entry->maxkeys,
+		      __entry->qnbytes, __entry->maxbytes,
+		      __entry->reqbytes)
+	    );
+
+TRACE_EVENT(key_link,
+	    TP_PROTO(const struct key *keyring, const struct key *key),
+
+	    TP_ARGS(keyring, key),
+
+	    TP_STRUCT__entry(
+		    __field(key_serial_t,	keyring)
+		    __field(key_serial_t,	key)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->keyring = keyring->serial;
+		    __entry->key = key->serial;
+			   ),
+
+	    TP_printk("key=%08x to=%08x",
+		      __entry->key, __entry->keyring)
+	    );
+
+TRACE_EVENT(key_unlink,
+	    TP_PROTO(const struct key *keyring, const struct key *key),
+
+	    TP_ARGS(keyring, key),
+
+	    TP_STRUCT__entry(
+		    __field(key_serial_t,	keyring)
+		    __field(key_serial_t,	key)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->keyring = keyring->serial;
+		    __entry->key = key->serial;
+			   ),
+
+	    TP_printk("key=%08x from=%08x",
+		      __entry->key, __entry->keyring)
+	    );
+
+TRACE_EVENT(key_move,
+	    TP_PROTO(const struct key *from, const struct key *to,
+		     const struct key *key),
+
+	    TP_ARGS(from, to, key),
+
+	    TP_STRUCT__entry(
+		    __field(key_serial_t,	from)
+		    __field(key_serial_t,	to)
+		    __field(key_serial_t,	key)
+			     ),
+
+	    TP_fast_assign(
+		    __entry->from = from->serial;
+		    __entry->to = to->serial;
+		    __entry->key = key->serial;
+			   ),
+
+	    TP_printk("key=%08x from=%08x to=%08x",
+		      __entry->key, __entry->from, __entry->to)
+	    );
+
+TRACE_EVENT(key_clear,
+	    TP_PROTO(const struct key *keyring),
+	    TP_ARGS(keyring),
+	    TP_STRUCT__entry(
+		    __field(key_serial_t,	keyring)
+			     ),
+	    TP_fast_assign(
+		    __entry->keyring = keyring->serial;
+			   ),
+	    TP_printk("key=%08x",
+		      __entry->keyring)
+	    );
+
+TRACE_EVENT(key_revoke,
+	    TP_PROTO(const struct key *key),
+	    TP_ARGS(key),
+	    TP_STRUCT__entry(
+		    __field(key_serial_t,	key)
+			     ),
+	    TP_fast_assign(
+		    __entry->key = key->serial;
+			   ),
+	    TP_printk("key=%08x",
+		      __entry->key)
+	    );
+
+TRACE_EVENT(key_invalidate,
+	    TP_PROTO(const struct key *key),
+	    TP_ARGS(key),
+	    TP_STRUCT__entry(
+		    __field(key_serial_t,	key)
+			     ),
+	    TP_fast_assign(
+		    __entry->key = key->serial;
+			   ),
+	    TP_printk("key=%08x",
+		      __entry->key)
+	    );
+
+TRACE_EVENT(key_gc,
+	    TP_PROTO(const struct key *key),
+	    TP_ARGS(key),
+	    TP_STRUCT__entry(
+		    __field(key_serial_t,	key)
+			     ),
+	    TP_fast_assign(
+		    __entry->key = key->serial;
+			   ),
+	    TP_printk("key=%08x",
+		      __entry->key)
+	    );
+
+#undef EM
+#undef E_
+#endif /* _TRACE_KEY_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/security/keys/gc.c b/security/keys/gc.c
index 7d687b0962b1..47f857653854 100644
--- a/security/keys/gc.c
+++ b/security/keys/gc.c
@@ -141,6 +141,7 @@ static noinline void key_gc_unused_keys(struct list_head *keys)
 
 		list_del(&key->graveyard_link);
 
+		trace_key_gc(key);
 		kdebug("- %u", key->serial);
 		key_check(key);
 
@@ -163,6 +164,8 @@ static noinline void key_gc_unused_keys(struct list_head *keys)
 		key_put_tag(key->domain_tag);
 		kfree(key->description);
 
+		trace_key_ref(key->serial, refcount_read(&key->usage),
+			      key_trace_ref_free, 0);
 		memzero_explicit(key, sizeof(*key));
 		kmem_cache_free(key_jar, key);
 	}
@@ -331,6 +334,7 @@ static void key_garbage_collector(struct work_struct *work)
 	 */
 found_unreferenced_key:
 	kdebug("unrefd key %d", key->serial);
+	trace_key_ref(key->serial, refcount_read(&key->usage), key_trace_ref_gc, 0);
 	rb_erase(&key->serial_node, &key_serial_tree);
 	spin_unlock(&key_serial_lock);
 
diff --git a/security/keys/internal.h b/security/keys/internal.h
index 33c929a6bb97..87600683a7f5 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -20,6 +20,7 @@
 #include <linux/mm.h>
 #include <linux/vmalloc.h>
 #include <keys/key_user.h>
+#include <trace/events/key.h>
 
 struct iovec;
 
diff --git a/security/keys/key.c b/security/keys/key.c
index 59cffb6f9b94..abb8d60a0dc2 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -14,6 +14,7 @@
 #include <linux/workqueue.h>
 #include <linux/random.h>
 #include <linux/err.h>
+#define CREATE_TRACE_POINTS
 #include "internal.h"
 
 struct kmem_cache *key_jar;
@@ -264,12 +265,15 @@ struct key *key_alloc(struct key_type *type, const char *desc,
 		if (!(flags & KEY_ALLOC_QUOTA_OVERRUN)) {
 			if (user->qnkeys + 1 > maxkeys ||
 			    user->qnbytes + quotalen > maxbytes ||
-			    user->qnbytes + quotalen < user->qnbytes)
+			    user->qnbytes + quotalen < user->qnbytes) {
+				trace_key_edquot(user, maxkeys, maxbytes, quotalen);
 				goto no_quota;
+			}
 		}
 
 		user->qnkeys++;
 		user->qnbytes += quotalen;
+		trace_key_quota(user, +1, quotalen);
 		spin_unlock_irqrestore(&user->lock, irqflags);
 	}
 
@@ -319,7 +323,10 @@ struct key *key_alloc(struct key_type *type, const char *desc,
 	/* publish the key by giving it a serial number */
 	refcount_inc(&key->domain_tag->usage);
 	atomic_inc(&user->nkeys);
+	trace_key_quota(user, 0, 0);
 	key_alloc_serial(key);
+	trace_key_alloc(key);
+	trace_key_ref(key->serial, 1, key_trace_ref_alloc, __builtin_return_address(0));
 
 error:
 	return key;
@@ -331,6 +338,7 @@ struct key *key_alloc(struct key_type *type, const char *desc,
 		spin_lock_irqsave(&user->lock, irqflags);
 		user->qnkeys--;
 		user->qnbytes -= quotalen;
+		trace_key_quota(user, -1, -quotalen);
 		spin_unlock_irqrestore(&user->lock, irqflags);
 	}
 	key_user_put(user);
@@ -344,6 +352,7 @@ struct key *key_alloc(struct key_type *type, const char *desc,
 		spin_lock_irqsave(&user->lock, irqflags);
 		user->qnkeys--;
 		user->qnbytes -= quotalen;
+		trace_key_quota(user, -1, quotalen);
 		spin_unlock_irqrestore(&user->lock, irqflags);
 	}
 	key_user_put(user);
@@ -388,11 +397,13 @@ int key_payload_reserve(struct key *key, size_t datalen)
 		if (delta > 0 &&
 		    (key->user->qnbytes + delta > maxbytes ||
 		     key->user->qnbytes + delta < key->user->qnbytes)) {
+			trace_key_edquot(key->user, 0, maxbytes, datalen);
 			ret = -EDQUOT;
 		}
 		else {
 			key->user->qnbytes += delta;
 			key->quotalen += delta;
+			trace_key_quota(key->user, 0, delta);
 		}
 		spin_unlock_irqrestore(&key->user->lock, flags);
 	}
@@ -447,6 +458,7 @@ static int __key_instantiate_and_link(struct key *key,
 		if (ret == 0) {
 			/* mark the key as being instantiated */
 			atomic_inc(&key->user->nikeys);
+			trace_key_instantiate(key, prep);
 			mark_key_instantiated(key, 0);
 			notify_key(key, NOTIFY_KEY_INSTANTIATED, 0);
 
@@ -604,6 +616,7 @@ int key_reject_and_link(struct key *key,
 	if (key->state == KEY_IS_UNINSTANTIATED) {
 		/* mark the key as being negatively instantiated */
 		atomic_inc(&key->user->nikeys);
+		trace_key_reject(key, -error);
 		mark_key_instantiated(key, -error);
 		notify_key(key, NOTIFY_KEY_INSTANTIATED, -error);
 		key_set_expiry(key, ktime_get_real_seconds() + timeout);
@@ -641,10 +654,15 @@ EXPORT_SYMBOL(key_reject_and_link);
  *
  * Get a reference on a key, if not NULL, and return the parameter.
  */
-struct key *key_get(struct key *key)
+noinline struct key *key_get(struct key *key)
 {
-	if (key)
-		refcount_inc(&key->usage);
+	if (key) {
+		int r;
+
+		__refcount_inc(&key->usage, &r);
+		trace_key_ref(key->serial, r + 1, key_trace_ref_get,
+			      __builtin_return_address(0));
+	}
 	return key;
 }
 EXPORT_SYMBOL(key_get);
@@ -656,10 +674,14 @@ EXPORT_SYMBOL(key_get);
  * Get a reference on a key unless it has no references and return true if
  * successful.  @key must not be NULL.
  */
-struct key *key_try_get(struct key *key)
+noinline struct key *key_try_get(struct key *key)
 {
-	if (!refcount_inc_not_zero(&key->usage))
+	int r;
+
+	if (!__refcount_inc_not_zero(&key->usage, &r))
 		return NULL;
+	trace_key_ref(key->serial, r + 1, key_trace_ref_try_get,
+		      __builtin_return_address(0));
 	return key;
 }
 
@@ -671,12 +693,19 @@ struct key *key_try_get(struct key *key)
  * schedule the cleanup task to come and pull it out of the tree in process
  * context at some later time.
  */
-void key_put(struct key *key)
+noinline void key_put(struct key *key)
 {
 	if (key) {
+		key_serial_t serial = key->serial;
+		bool zero;
+		int r;
+
 		key_check(key);
 
-		if (refcount_dec_and_test(&key->usage)) {
+		zero = __refcount_dec_and_test(&key->usage, &r);
+		trace_key_ref(serial, r - 1, key_trace_ref_put,
+			      __builtin_return_address(0));
+		if (zero) {
 			unsigned long flags;
 
 			/* deal with the user's key tracking and quota */
@@ -684,6 +713,7 @@ void key_put(struct key *key)
 				spin_lock_irqsave(&key->user->lock, flags);
 				key->user->qnkeys--;
 				key->user->qnbytes -= key->quotalen;
+				trace_key_quota(key->user, -1, -key->quotalen);
 				spin_unlock_irqrestore(&key->user->lock, flags);
 			}
 			schedule_work(&key_gc_work);
@@ -807,6 +837,7 @@ static inline key_ref_t __key_update(key_ref_t key_ref,
 	ret = key->type->update(key, prep);
 	if (ret == 0) {
 		/* Updating a negative key positively instantiates it */
+		trace_key_update(key, prep);
 		mark_key_instantiated(key, 0);
 		notify_key(key, NOTIFY_KEY_UPDATED, 0);
 	}
@@ -1131,6 +1162,7 @@ int key_update(key_ref_t key_ref, const void *payload, size_t plen)
 	ret = key->type->update(key, &prep);
 	if (ret == 0) {
 		/* Updating a negative key positively instantiates it */
+		trace_key_update(key, &prep);
 		mark_key_instantiated(key, 0);
 		notify_key(key, NOTIFY_KEY_UPDATED, 0);
 	}
@@ -1166,6 +1198,7 @@ void key_revoke(struct key *key)
 	 */
 	down_write_nested(&key->sem, 1);
 	if (!test_and_set_bit(KEY_FLAG_REVOKED, &key->flags)) {
+		trace_key_revoke(key);
 		notify_key(key, NOTIFY_KEY_REVOKED, 0);
 		if (key->type->revoke)
 			key->type->revoke(key);
@@ -1198,6 +1231,7 @@ void key_invalidate(struct key *key)
 	if (!test_bit(KEY_FLAG_INVALIDATED, &key->flags)) {
 		down_write_nested(&key->sem, 1);
 		if (!test_and_set_bit(KEY_FLAG_INVALIDATED, &key->flags)) {
+			trace_key_invalidate(key);
 			notify_key(key, NOTIFY_KEY_INVALIDATED, 0);
 			key_schedule_gc_links();
 		}
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index ab927a142f51..f2ef898209e6 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -1020,11 +1020,13 @@ long keyctl_chown_key(key_serial_t id, uid_t user, gid_t group)
 
 			newowner->qnkeys++;
 			newowner->qnbytes += key->quotalen;
+			trace_key_quota(newowner, +1, key->quotalen);
 			spin_unlock_irqrestore(&newowner->lock, flags);
 
 			spin_lock_irqsave(&key->user->lock, flags);
 			key->user->qnkeys--;
 			key->user->qnbytes -= key->quotalen;
+			trace_key_quota(newowner, -1, -key->quotalen);
 			spin_unlock_irqrestore(&key->user->lock, flags);
 		}
 
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index a09a4c2b1bcb..d67a60142318 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -1368,6 +1368,7 @@ void __key_link(struct key *keyring, struct key *key,
 		struct assoc_array_edit **_edit)
 {
 	key_get(key);
+	trace_key_link(keyring, key);
 	assoc_array_insert_set_object(*_edit, keyring_key_to_ptr(key));
 	assoc_array_apply_edit(*_edit);
 	*_edit = NULL;
@@ -1506,6 +1507,7 @@ static int __key_unlink_begin(struct key *keyring, struct key *key,
 static void __key_unlink(struct key *keyring, struct key *key,
 			 struct assoc_array_edit **_edit)
 {
+	trace_key_unlink(keyring, key);
 	assoc_array_apply_edit(*_edit);
 	notify_key(keyring, NOTIFY_KEY_UNLINKED, key_serial(key));
 	*_edit = NULL;
@@ -1625,6 +1627,7 @@ int key_move(struct key *key,
 	if (ret < 0)
 		goto error;
 
+	trace_key_move(from_keyring, to_keyring, key);
 	__key_unlink(from_keyring, key, &from_edit);
 	__key_link(to_keyring, key, &to_edit);
 error:
@@ -1654,6 +1657,7 @@ int keyring_clear(struct key *keyring)
 
 	down_write(&keyring->sem);
 
+	trace_key_clear(keyring);
 	edit = assoc_array_clear(&keyring->keys, &keyring_assoc_array_ops);
 	if (IS_ERR(edit)) {
 		ret = PTR_ERR(edit);
@@ -1697,14 +1701,27 @@ static bool key_is_dead(const struct key *key, time64_t limit)
 	if (expiry != TIME64_MAX) {
 		if (!(key->type->flags & KEY_TYPE_INSTANT_REAP))
 			expiry += key_gc_delay;
-		if (expiry <= limit)
+		if (expiry <= limit) {
+			trace_key_dead(key, key_trace_dead_expired);
 			return true;
+		}
+	}
+
+	if (test_bit(KEY_FLAG_DEAD, &key->flags)) {
+		trace_key_dead(key, key_trace_dead_type_removed);
+		return true;
+	}
+
+	if (test_bit(KEY_FLAG_INVALIDATED, &key->flags)) {
+		trace_key_dead(key, key_trace_dead_invalidated);
+		return true;
 	}
 
-	return
-		key->flags & ((1 << KEY_FLAG_DEAD) |
-			      (1 << KEY_FLAG_INVALIDATED)) ||
-		key->domain_tag->removed;
+	if (key->domain_tag->removed) {
+		trace_key_dead(key, key_trace_dead_domain_removed);
+		return true;
+	}
+	return false;
 }
 
 static bool keyring_gc_select_iterator(void *object, void *iterator_data)

Re: [PATCH 7/7] keys: Add tracepoints for the keyrings facility

[Jarkko Sakkinen]

On Wed Aug 21, 2024 at 3:36 PM EEST, David Howells wrote:
> Add some tracepoints to aid in debuggin the keyrings facility and
> applications that use it.  A number of events and operations are traceable,
> including:
>
>   - Allocation
>   - Refcounting
>   - Instantiation and negative instantiation/rejection
>   - Update
>   - Detection of key being dead
>   - Key quota changes
>   - Key quota failure
>   - Link, unlink and move
>   - Keyring clearance
>   - Revocation and invalidation
>   - Garbage collection
>
> Signed-off-by: David Howells <dhowells@redhat.com>
> cc: Jarkko Sakkinen <jarkko@kernel.org>
> cc: keyrings@vger.kernel.org
> cc: linux-security-module@vger.kernel.org

I have immediate use for this when I take the time and refine [1] so
I guess that goes for existential reason :-)

> ---
>  include/trace/events/key.h | 401 +++++++++++++++++++++++++++++++++++++
>  security/keys/gc.c         |   4 +
>  security/keys/internal.h   |   1 +
>  security/keys/key.c        |  50 ++++-
>  security/keys/keyctl.c     |   2 +
>  security/keys/keyring.c    |  27 ++-
>  6 files changed, 472 insertions(+), 13 deletions(-)
>  create mode 100644 include/trace/events/key.h
>
> diff --git a/include/trace/events/key.h b/include/trace/events/key.h
> new file mode 100644
> index 000000000000..b3f8c39cc0e8
> --- /dev/null
> +++ b/include/trace/events/key.h
> @@ -0,0 +1,401 @@
> +/* Keyrings tracepoints
> + *
> + * Copyright (C) 2024 Red Hat, Inc. All Rights Reserved.
> + * Written by David Howells (dhowells@redhat.com)
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public Licence
> + * as published by the Free Software Foundation; either version
> + * 2 of the Licence, or (at your option) any later version.
> + */
> +#undef TRACE_SYSTEM
> +#define TRACE_SYSTEM key
> +
> +#if !defined(_TRACE_KEY_H) || defined(TRACE_HEADER_MULTI_READ)
> +#define _TRACE_KEY_H
> +
> +#include <linux/tracepoint.h>
> +
> +struct key;
> +
> +/*
> + * Declare tracing information enums and their string mappings for display.
> + */
> +#define key_ref_traces \
> +	EM(key_trace_ref_alloc,			"ALLOC") \
> +	EM(key_trace_ref_free,			"FREE ") \
> +	EM(key_trace_ref_gc,			"GC   ") \
> +	EM(key_trace_ref_get,			"GET  ") \
> +	EM(key_trace_ref_put,			"PUT  ") \
> +	E_(key_trace_ref_try_get,		"GET  ")
> +
> +#define key_dead_traces \
> +	EM(key_trace_dead_type_removed,		"TYPR") \
> +	EM(key_trace_dead_domain_removed,	"DOMR") \
> +	EM(key_trace_dead_expired,		"EXPD") \
> +	E_(key_trace_dead_invalidated,		"INVL")
> +
> +/*
> + * Generate enums for tracing information.
> + */
> +#ifndef __NETFS_DECLARE_TRACE_ENUMS_ONCE_ONLY
> +#define __NETFS_DECLARE_TRACE_ENUMS_ONCE_ONLY
> +
> +#undef EM
> +#undef E_
> +#define EM(a, b) a,
> +#define E_(a, b) a
> +
> +enum key_dead_trace	{ key_dead_traces } __mode(byte);
> +enum key_ref_trace	{ key_ref_traces } __mode(byte);
> +
> +#endif /* end __RXRPC_DECLARE_TRACE_ENUMS_ONCE_ONLY */
> +
> +/*
> + * Export enum symbols via userspace.
> + */
> +#undef EM
> +#undef E_
> +#define EM(a, b) TRACE_DEFINE_ENUM(a);
> +#define E_(a, b) TRACE_DEFINE_ENUM(a);
> +
> +key_dead_traces;
> +key_ref_traces;
> +
> +/*
> + * Now redefine the EM() and E_() macros to map the enums to the strings that
> + * will be printed in the output.
> + */
> +#undef EM
> +#undef E_
> +#define EM(a, b)	{ a, b },
> +#define E_(a, b)	{ a, b }
> +
> +TRACE_EVENT(key_alloc,
> +	    TP_PROTO(const struct key *key),
> +
> +	    TP_ARGS(key),
> +
> +	    TP_STRUCT__entry(
> +		    __field(key_serial_t,		key)
> +		    __field(uid_t,			uid)
> +		    __array(char,			type, 8)
> +		    __array(char,			desc, 24)
> +			     ),
> +
> +	    TP_fast_assign(
> +		    __entry->key = key->serial;
> +		    __entry->uid = from_kuid(&init_user_ns, key->uid);
> +		    strncpy(__entry->type, key->type->name, sizeof(__entry->type) - 1);
> +		    strncpy(__entry->desc, key->description ?: "", sizeof(__entry->desc) - 1);
> +		    __entry->type[sizeof(__entry->type) - 1] = 0;
> +		    __entry->desc[sizeof(__entry->desc) - 1] = 0;
> +			   ),
> +
> +	    TP_printk("key=%08x uid=%08x t=%s d=%s",
> +		      __entry->key,
> +		      __entry->uid,
> +		      __entry->type,
> +		      __entry->desc)
> +	    );
> +
> +TRACE_EVENT(key_ref,
> +	    TP_PROTO(key_serial_t key, unsigned int ref, enum key_ref_trace trace,
> +		     const void *where),
> +
> +	    TP_ARGS(key, ref, trace, where),
> +
> +	    TP_STRUCT__entry(
> +		    __field(key_serial_t,		key)
> +		    __field(enum key_ref_trace,		trace)
> +		    __field(unsigned int,		ref)
> +		    __field(const void *,		where)
> +			     ),
> +
> +	    TP_fast_assign(
> +		    __entry->key = key;
> +		    __entry->trace = trace;
> +		    __entry->ref = ref;
> +		    __entry->where = where;
> +			   ),
> +
> +	    TP_printk("key=%08x %s r=%d pc=%pSR",
> +		      __entry->key,
> +		      __print_symbolic(__entry->trace, key_ref_traces),
> +		      __entry->ref,
> +		      __entry->where)
> +	    );
> +
> +TRACE_EVENT(key_instantiate,
> +	    TP_PROTO(const struct key *key, const struct key_preparsed_payload *prep),
> +
> +	    TP_ARGS(key, prep),
> +
> +	    TP_STRUCT__entry(
> +		    __field(key_serial_t,	key)
> +		    __field(unsigned int,	datalen)
> +		    __field(unsigned int,	quotalen)
> +			     ),
> +
> +	    TP_fast_assign(
> +		    __entry->key = key->serial;
> +		    __entry->datalen = prep->datalen;
> +		    __entry->quotalen = prep->quotalen;
> +			   ),
> +
> +	    TP_printk("key=%08x dlen=%u qlen=%u",
> +		      __entry->key,
> +		      __entry->datalen,
> +		      __entry->quotalen)
> +	    );
> +
> +TRACE_EVENT(key_reject,
> +	    TP_PROTO(const struct key *key, int error),
> +
> +	    TP_ARGS(key, error),
> +
> +	    TP_STRUCT__entry(
> +		    __field(key_serial_t,	key)
> +		    __field(int,		error)
> +			     ),
> +
> +	    TP_fast_assign(
> +		    __entry->key = key->serial;
> +		    __entry->error = error;
> +			   ),
> +
> +	    TP_printk("key=%08x err=%d",
> +		      __entry->key,
> +		      __entry->error)
> +	    );
> +
> +TRACE_EVENT(key_update,
> +	    TP_PROTO(const struct key *key, const struct key_preparsed_payload *prep),
> +
> +	    TP_ARGS(key, prep),
> +
> +	    TP_STRUCT__entry(
> +		    __field(key_serial_t,	key)
> +		    __field(unsigned int,	datalen)
> +		    __field(unsigned int,	quotalen)
> +			     ),
> +
> +	    TP_fast_assign(
> +		    __entry->key = key->serial;
> +		    __entry->datalen = prep->datalen;
> +		    __entry->quotalen = prep->quotalen;
> +			   ),
> +
> +	    TP_printk("key=%08x dlen=%u qlen=%u",
> +		      __entry->key,
> +		      __entry->datalen,
> +		      __entry->quotalen)
> +	    );
> +
> +TRACE_EVENT(key_dead,
> +	    TP_PROTO(const struct key *key, enum key_dead_trace trace),
> +
> +	    TP_ARGS(key, trace),
> +
> +	    TP_STRUCT__entry(
> +		    __field(key_serial_t,		key)
> +		    __field(enum key_dead_trace,	trace)
> +			     ),
> +
> +	    TP_fast_assign(
> +		    __entry->key = key->serial;
> +		    __entry->trace = trace;
> +			   ),
> +
> +	    TP_printk("key=%08x %s",
> +		      __entry->key,
> +		      __print_symbolic(__entry->trace, key_dead_traces))
> +	    );
> +
> +TRACE_EVENT(key_quota,
> +	    TP_PROTO(const struct key_user *user, int change_keys, int change_bytes),
> +
> +	    TP_ARGS(user, change_keys, change_bytes),
> +
> +	    TP_STRUCT__entry(
> +		    __field(uid_t,		uid)
> +		    __field(unsigned int,	nkeys)
> +		    __field(unsigned int,	nikeys)
> +		    __field(unsigned int,	qnkeys)
> +		    __field(unsigned int,	qnbytes)
> +		    __field(int,		change_keys)
> +		    __field(int,		change_bytes)
> +			     ),
> +
> +	    TP_fast_assign(
> +		    __entry->uid = from_kuid(&init_user_ns, user->uid);
> +		    __entry->nkeys = atomic_read(&user->nkeys);
> +		    __entry->nikeys = atomic_read(&user->nikeys);
> +		    __entry->qnkeys = user->qnkeys;
> +		    __entry->qnbytes = user->qnbytes;
> +		    __entry->change_keys = change_keys;
> +		    __entry->change_bytes = change_bytes;
> +			   ),
> +
> +	    TP_printk("uid=%d nkeys=%u/%u qkeys=%u qpay=%u ckeys=%d cpay=%d",
> +		      __entry->uid,
> +		      __entry->nikeys, __entry->nkeys,
> +		      __entry->qnkeys,
> +		      __entry->qnbytes,
> +		      __entry->change_keys, __entry->change_bytes)
> +	    );
> +
> +TRACE_EVENT(key_edquot,
> +	    TP_PROTO(const struct key_user *user, unsigned int maxkeys,
> +		     unsigned int maxbytes, unsigned int reqbytes),
> +
> +	    TP_ARGS(user, maxkeys, maxbytes, reqbytes),
> +
> +	    TP_STRUCT__entry(
> +		    __field(uid_t,		uid)
> +		    __field(unsigned int,	nkeys)
> +		    __field(unsigned int,	nikeys)
> +		    __field(unsigned int,	qnkeys)
> +		    __field(unsigned int,	qnbytes)
> +		    __field(unsigned int,	maxkeys)
> +		    __field(unsigned int,	maxbytes)
> +		    __field(unsigned int,	reqbytes)
> +			     ),
> +
> +	    TP_fast_assign(
> +		    __entry->uid = from_kuid(&init_user_ns, user->uid);
> +		    __entry->nkeys = atomic_read(&user->nkeys);
> +		    __entry->nikeys = atomic_read(&user->nikeys);
> +		    __entry->qnkeys = user->qnkeys;
> +		    __entry->qnbytes = user->qnbytes;
> +		    __entry->maxkeys = maxkeys;
> +		    __entry->maxbytes = maxbytes;
> +		    __entry->reqbytes = reqbytes;
> +			   ),
> +
> +	    TP_printk("u=%d nkeys=%u/%u qkeys=%u/%u qpay=%u/%u cpay=%u",
> +		      __entry->uid,
> +		      __entry->nikeys, __entry->nkeys,
> +		      __entry->qnkeys, __entry->maxkeys,
> +		      __entry->qnbytes, __entry->maxbytes,
> +		      __entry->reqbytes)
> +	    );
> +
> +TRACE_EVENT(key_link,
> +	    TP_PROTO(const struct key *keyring, const struct key *key),
> +
> +	    TP_ARGS(keyring, key),
> +
> +	    TP_STRUCT__entry(
> +		    __field(key_serial_t,	keyring)
> +		    __field(key_serial_t,	key)
> +			     ),
> +
> +	    TP_fast_assign(
> +		    __entry->keyring = keyring->serial;
> +		    __entry->key = key->serial;
> +			   ),
> +
> +	    TP_printk("key=%08x to=%08x",
> +		      __entry->key, __entry->keyring)
> +	    );
> +
> +TRACE_EVENT(key_unlink,
> +	    TP_PROTO(const struct key *keyring, const struct key *key),
> +
> +	    TP_ARGS(keyring, key),
> +
> +	    TP_STRUCT__entry(
> +		    __field(key_serial_t,	keyring)
> +		    __field(key_serial_t,	key)
> +			     ),
> +
> +	    TP_fast_assign(
> +		    __entry->keyring = keyring->serial;
> +		    __entry->key = key->serial;
> +			   ),
> +
> +	    TP_printk("key=%08x from=%08x",
> +		      __entry->key, __entry->keyring)
> +	    );
> +
> +TRACE_EVENT(key_move,
> +	    TP_PROTO(const struct key *from, const struct key *to,
> +		     const struct key *key),
> +
> +	    TP_ARGS(from, to, key),
> +
> +	    TP_STRUCT__entry(
> +		    __field(key_serial_t,	from)
> +		    __field(key_serial_t,	to)
> +		    __field(key_serial_t,	key)
> +			     ),
> +
> +	    TP_fast_assign(
> +		    __entry->from = from->serial;
> +		    __entry->to = to->serial;
> +		    __entry->key = key->serial;
> +			   ),
> +
> +	    TP_printk("key=%08x from=%08x to=%08x",
> +		      __entry->key, __entry->from, __entry->to)
> +	    );
> +
> +TRACE_EVENT(key_clear,
> +	    TP_PROTO(const struct key *keyring),
> +	    TP_ARGS(keyring),
> +	    TP_STRUCT__entry(
> +		    __field(key_serial_t,	keyring)
> +			     ),
> +	    TP_fast_assign(
> +		    __entry->keyring = keyring->serial;
> +			   ),
> +	    TP_printk("key=%08x",
> +		      __entry->keyring)
> +	    );
> +
> +TRACE_EVENT(key_revoke,
> +	    TP_PROTO(const struct key *key),
> +	    TP_ARGS(key),
> +	    TP_STRUCT__entry(
> +		    __field(key_serial_t,	key)
> +			     ),
> +	    TP_fast_assign(
> +		    __entry->key = key->serial;
> +			   ),
> +	    TP_printk("key=%08x",
> +		      __entry->key)
> +	    );
> +
> +TRACE_EVENT(key_invalidate,
> +	    TP_PROTO(const struct key *key),
> +	    TP_ARGS(key),
> +	    TP_STRUCT__entry(
> +		    __field(key_serial_t,	key)
> +			     ),
> +	    TP_fast_assign(
> +		    __entry->key = key->serial;
> +			   ),
> +	    TP_printk("key=%08x",
> +		      __entry->key)
> +	    );
> +
> +TRACE_EVENT(key_gc,
> +	    TP_PROTO(const struct key *key),
> +	    TP_ARGS(key),
> +	    TP_STRUCT__entry(
> +		    __field(key_serial_t,	key)
> +			     ),
> +	    TP_fast_assign(
> +		    __entry->key = key->serial;
> +			   ),
> +	    TP_printk("key=%08x",
> +		      __entry->key)
> +	    );
> +
> +#undef EM
> +#undef E_
> +#endif /* _TRACE_KEY_H */
> +
> +/* This part must be outside protection */
> +#include <trace/define_trace.h>
> diff --git a/security/keys/gc.c b/security/keys/gc.c
> index 7d687b0962b1..47f857653854 100644
> --- a/security/keys/gc.c
> +++ b/security/keys/gc.c
> @@ -141,6 +141,7 @@ static noinline void key_gc_unused_keys(struct list_head *keys)
>  
>  		list_del(&key->graveyard_link);
>  
> +		trace_key_gc(key);
>  		kdebug("- %u", key->serial);
>  		key_check(key);
>  
> @@ -163,6 +164,8 @@ static noinline void key_gc_unused_keys(struct list_head *keys)
>  		key_put_tag(key->domain_tag);
>  		kfree(key->description);
>  
> +		trace_key_ref(key->serial, refcount_read(&key->usage),
> +			      key_trace_ref_free, 0);
>  		memzero_explicit(key, sizeof(*key));
>  		kmem_cache_free(key_jar, key);
>  	}
> @@ -331,6 +334,7 @@ static void key_garbage_collector(struct work_struct *work)
>  	 */
>  found_unreferenced_key:
>  	kdebug("unrefd key %d", key->serial);
> +	trace_key_ref(key->serial, refcount_read(&key->usage), key_trace_ref_gc, 0);
>  	rb_erase(&key->serial_node, &key_serial_tree);
>  	spin_unlock(&key_serial_lock);
>  
> diff --git a/security/keys/internal.h b/security/keys/internal.h
> index 33c929a6bb97..87600683a7f5 100644
> --- a/security/keys/internal.h
> +++ b/security/keys/internal.h
> @@ -20,6 +20,7 @@
>  #include <linux/mm.h>
>  #include <linux/vmalloc.h>
>  #include <keys/key_user.h>
> +#include <trace/events/key.h>
>  
>  struct iovec;
>  
> diff --git a/security/keys/key.c b/security/keys/key.c
> index 59cffb6f9b94..abb8d60a0dc2 100644
> --- a/security/keys/key.c
> +++ b/security/keys/key.c
> @@ -14,6 +14,7 @@
>  #include <linux/workqueue.h>
>  #include <linux/random.h>
>  #include <linux/err.h>
> +#define CREATE_TRACE_POINTS
>  #include "internal.h"
>  
>  struct kmem_cache *key_jar;
> @@ -264,12 +265,15 @@ struct key *key_alloc(struct key_type *type, const char *desc,
>  		if (!(flags & KEY_ALLOC_QUOTA_OVERRUN)) {
>  			if (user->qnkeys + 1 > maxkeys ||
>  			    user->qnbytes + quotalen > maxbytes ||
> -			    user->qnbytes + quotalen < user->qnbytes)
> +			    user->qnbytes + quotalen < user->qnbytes) {
> +				trace_key_edquot(user, maxkeys, maxbytes, quotalen);
>  				goto no_quota;
> +			}
>  		}
>  
>  		user->qnkeys++;
>  		user->qnbytes += quotalen;
> +		trace_key_quota(user, +1, quotalen);
>  		spin_unlock_irqrestore(&user->lock, irqflags);
>  	}
>  
> @@ -319,7 +323,10 @@ struct key *key_alloc(struct key_type *type, const char *desc,
>  	/* publish the key by giving it a serial number */
>  	refcount_inc(&key->domain_tag->usage);
>  	atomic_inc(&user->nkeys);
> +	trace_key_quota(user, 0, 0);
>  	key_alloc_serial(key);
> +	trace_key_alloc(key);
> +	trace_key_ref(key->serial, 1, key_trace_ref_alloc, __builtin_return_address(0));
>  
>  error:
>  	return key;
> @@ -331,6 +338,7 @@ struct key *key_alloc(struct key_type *type, const char *desc,
>  		spin_lock_irqsave(&user->lock, irqflags);
>  		user->qnkeys--;
>  		user->qnbytes -= quotalen;
> +		trace_key_quota(user, -1, -quotalen);
>  		spin_unlock_irqrestore(&user->lock, irqflags);
>  	}
>  	key_user_put(user);
> @@ -344,6 +352,7 @@ struct key *key_alloc(struct key_type *type, const char *desc,
>  		spin_lock_irqsave(&user->lock, irqflags);
>  		user->qnkeys--;
>  		user->qnbytes -= quotalen;
> +		trace_key_quota(user, -1, quotalen);
>  		spin_unlock_irqrestore(&user->lock, irqflags);
>  	}
>  	key_user_put(user);
> @@ -388,11 +397,13 @@ int key_payload_reserve(struct key *key, size_t datalen)
>  		if (delta > 0 &&
>  		    (key->user->qnbytes + delta > maxbytes ||
>  		     key->user->qnbytes + delta < key->user->qnbytes)) {
> +			trace_key_edquot(key->user, 0, maxbytes, datalen);
>  			ret = -EDQUOT;
>  		}
>  		else {
>  			key->user->qnbytes += delta;
>  			key->quotalen += delta;
> +			trace_key_quota(key->user, 0, delta);
>  		}
>  		spin_unlock_irqrestore(&key->user->lock, flags);
>  	}
> @@ -447,6 +458,7 @@ static int __key_instantiate_and_link(struct key *key,
>  		if (ret == 0) {
>  			/* mark the key as being instantiated */
>  			atomic_inc(&key->user->nikeys);
> +			trace_key_instantiate(key, prep);
>  			mark_key_instantiated(key, 0);
>  			notify_key(key, NOTIFY_KEY_INSTANTIATED, 0);
>  
> @@ -604,6 +616,7 @@ int key_reject_and_link(struct key *key,
>  	if (key->state == KEY_IS_UNINSTANTIATED) {
>  		/* mark the key as being negatively instantiated */
>  		atomic_inc(&key->user->nikeys);
> +		trace_key_reject(key, -error);
>  		mark_key_instantiated(key, -error);
>  		notify_key(key, NOTIFY_KEY_INSTANTIATED, -error);
>  		key_set_expiry(key, ktime_get_real_seconds() + timeout);
> @@ -641,10 +654,15 @@ EXPORT_SYMBOL(key_reject_and_link);
>   *
>   * Get a reference on a key, if not NULL, and return the parameter.
>   */
> -struct key *key_get(struct key *key)
> +noinline struct key *key_get(struct key *key)
>  {
> -	if (key)
> -		refcount_inc(&key->usage);
> +	if (key) {
> +		int r;
> +
> +		__refcount_inc(&key->usage, &r);
> +		trace_key_ref(key->serial, r + 1, key_trace_ref_get,
> +			      __builtin_return_address(0));
> +	}
>  	return key;
>  }
>  EXPORT_SYMBOL(key_get);
> @@ -656,10 +674,14 @@ EXPORT_SYMBOL(key_get);
>   * Get a reference on a key unless it has no references and return true if
>   * successful.  @key must not be NULL.
>   */
> -struct key *key_try_get(struct key *key)
> +noinline struct key *key_try_get(struct key *key)
>  {
> -	if (!refcount_inc_not_zero(&key->usage))
> +	int r;
> +
> +	if (!__refcount_inc_not_zero(&key->usage, &r))
>  		return NULL;
> +	trace_key_ref(key->serial, r + 1, key_trace_ref_try_get,
> +		      __builtin_return_address(0));
>  	return key;
>  }
>  
> @@ -671,12 +693,19 @@ struct key *key_try_get(struct key *key)
>   * schedule the cleanup task to come and pull it out of the tree in process
>   * context at some later time.
>   */
> -void key_put(struct key *key)
> +noinline void key_put(struct key *key)
>  {
>  	if (key) {
> +		key_serial_t serial = key->serial;
> +		bool zero;
> +		int r;
> +
>  		key_check(key);
>  
> -		if (refcount_dec_and_test(&key->usage)) {
> +		zero = __refcount_dec_and_test(&key->usage, &r);
> +		trace_key_ref(serial, r - 1, key_trace_ref_put,
> +			      __builtin_return_address(0));
> +		if (zero) {
>  			unsigned long flags;
>  
>  			/* deal with the user's key tracking and quota */
> @@ -684,6 +713,7 @@ void key_put(struct key *key)
>  				spin_lock_irqsave(&key->user->lock, flags);
>  				key->user->qnkeys--;
>  				key->user->qnbytes -= key->quotalen;
> +				trace_key_quota(key->user, -1, -key->quotalen);
>  				spin_unlock_irqrestore(&key->user->lock, flags);
>  			}
>  			schedule_work(&key_gc_work);
> @@ -807,6 +837,7 @@ static inline key_ref_t __key_update(key_ref_t key_ref,
>  	ret = key->type->update(key, prep);
>  	if (ret == 0) {
>  		/* Updating a negative key positively instantiates it */
> +		trace_key_update(key, prep);
>  		mark_key_instantiated(key, 0);
>  		notify_key(key, NOTIFY_KEY_UPDATED, 0);
>  	}
> @@ -1131,6 +1162,7 @@ int key_update(key_ref_t key_ref, const void *payload, size_t plen)
>  	ret = key->type->update(key, &prep);
>  	if (ret == 0) {
>  		/* Updating a negative key positively instantiates it */
> +		trace_key_update(key, &prep);
>  		mark_key_instantiated(key, 0);
>  		notify_key(key, NOTIFY_KEY_UPDATED, 0);
>  	}
> @@ -1166,6 +1198,7 @@ void key_revoke(struct key *key)
>  	 */
>  	down_write_nested(&key->sem, 1);
>  	if (!test_and_set_bit(KEY_FLAG_REVOKED, &key->flags)) {
> +		trace_key_revoke(key);
>  		notify_key(key, NOTIFY_KEY_REVOKED, 0);
>  		if (key->type->revoke)
>  			key->type->revoke(key);
> @@ -1198,6 +1231,7 @@ void key_invalidate(struct key *key)
>  	if (!test_bit(KEY_FLAG_INVALIDATED, &key->flags)) {
>  		down_write_nested(&key->sem, 1);
>  		if (!test_and_set_bit(KEY_FLAG_INVALIDATED, &key->flags)) {
> +			trace_key_invalidate(key);
>  			notify_key(key, NOTIFY_KEY_INVALIDATED, 0);
>  			key_schedule_gc_links();
>  		}
> diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
> index ab927a142f51..f2ef898209e6 100644
> --- a/security/keys/keyctl.c
> +++ b/security/keys/keyctl.c
> @@ -1020,11 +1020,13 @@ long keyctl_chown_key(key_serial_t id, uid_t user, gid_t group)
>  
>  			newowner->qnkeys++;
>  			newowner->qnbytes += key->quotalen;
> +			trace_key_quota(newowner, +1, key->quotalen);
>  			spin_unlock_irqrestore(&newowner->lock, flags);
>  
>  			spin_lock_irqsave(&key->user->lock, flags);
>  			key->user->qnkeys--;
>  			key->user->qnbytes -= key->quotalen;
> +			trace_key_quota(newowner, -1, -key->quotalen);
>  			spin_unlock_irqrestore(&key->user->lock, flags);
>  		}
>  
> diff --git a/security/keys/keyring.c b/security/keys/keyring.c
> index a09a4c2b1bcb..d67a60142318 100644
> --- a/security/keys/keyring.c
> +++ b/security/keys/keyring.c
> @@ -1368,6 +1368,7 @@ void __key_link(struct key *keyring, struct key *key,
>  		struct assoc_array_edit **_edit)
>  {
>  	key_get(key);
> +	trace_key_link(keyring, key);
>  	assoc_array_insert_set_object(*_edit, keyring_key_to_ptr(key));
>  	assoc_array_apply_edit(*_edit);
>  	*_edit = NULL;
> @@ -1506,6 +1507,7 @@ static int __key_unlink_begin(struct key *keyring, struct key *key,
>  static void __key_unlink(struct key *keyring, struct key *key,
>  			 struct assoc_array_edit **_edit)
>  {
> +	trace_key_unlink(keyring, key);
>  	assoc_array_apply_edit(*_edit);
>  	notify_key(keyring, NOTIFY_KEY_UNLINKED, key_serial(key));
>  	*_edit = NULL;
> @@ -1625,6 +1627,7 @@ int key_move(struct key *key,
>  	if (ret < 0)
>  		goto error;
>  
> +	trace_key_move(from_keyring, to_keyring, key);
>  	__key_unlink(from_keyring, key, &from_edit);
>  	__key_link(to_keyring, key, &to_edit);
>  error:
> @@ -1654,6 +1657,7 @@ int keyring_clear(struct key *keyring)
>  
>  	down_write(&keyring->sem);
>  
> +	trace_key_clear(keyring);
>  	edit = assoc_array_clear(&keyring->keys, &keyring_assoc_array_ops);
>  	if (IS_ERR(edit)) {
>  		ret = PTR_ERR(edit);
> @@ -1697,14 +1701,27 @@ static bool key_is_dead(const struct key *key, time64_t limit)
>  	if (expiry != TIME64_MAX) {
>  		if (!(key->type->flags & KEY_TYPE_INSTANT_REAP))
>  			expiry += key_gc_delay;
> -		if (expiry <= limit)
> +		if (expiry <= limit) {
> +			trace_key_dead(key, key_trace_dead_expired);
>  			return true;
> +		}
> +	}
> +
> +	if (test_bit(KEY_FLAG_DEAD, &key->flags)) {
> +		trace_key_dead(key, key_trace_dead_type_removed);
> +		return true;
> +	}
> +
> +	if (test_bit(KEY_FLAG_INVALIDATED, &key->flags)) {
> +		trace_key_dead(key, key_trace_dead_invalidated);
> +		return true;
>  	}
>  
> -	return
> -		key->flags & ((1 << KEY_FLAG_DEAD) |
> -			      (1 << KEY_FLAG_INVALIDATED)) ||
> -		key->domain_tag->removed;
> +	if (key->domain_tag->removed) {
> +		trace_key_dead(key, key_trace_dead_domain_removed);
> +		return true;
> +	}
> +	return false;
>  }
>  
>  static bool keyring_gc_select_iterator(void *object, void *iterator_data)

Splits matter because you can "set and forget" stuff now there is not
much to review in this main patch because the change is so dead
obvious and at sight:

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>

I also gave quick test:

Tested-by: Jarkko Sakkinen <jarkko@kernel.org>

[1] TPM2 asymmetric keys:
    https://lore.kernel.org/linux-integrity/20240528210823.28798-1-jarkko@kernel.org/

BR, Jarkko

Re: [PATCH 7/7] keys: Add tracepoints for the keyrings facility

[Justin Stitt]

Hi,

On Wed, Aug 21, 2024 at 01:36:15PM GMT, David Howells wrote:
> Add some tracepoints to aid in debuggin the keyrings facility and
> applications that use it.  A number of events and operations are traceable,
> including:
> 
>   - Allocation
>   - Refcounting
>   - Instantiation and negative instantiation/rejection
>   - Update
>   - Detection of key being dead
>   - Key quota changes
>   - Key quota failure
>   - Link, unlink and move
>   - Keyring clearance
>   - Revocation and invalidation
>   - Garbage collection
> 
> Signed-off-by: David Howells <dhowells@redhat.com>
> cc: Jarkko Sakkinen <jarkko@kernel.org>
> cc: keyrings@vger.kernel.org
> cc: linux-security-module@vger.kernel.org
> ---
>  include/trace/events/key.h | 401 +++++++++++++++++++++++++++++++++++++
>  security/keys/gc.c         |   4 +
>  security/keys/internal.h   |   1 +
>  security/keys/key.c        |  50 ++++-
>  security/keys/keyctl.c     |   2 +
>  security/keys/keyring.c    |  27 ++-
>  6 files changed, 472 insertions(+), 13 deletions(-)
>  create mode 100644 include/trace/events/key.h
> 
> diff --git a/include/trace/events/key.h b/include/trace/events/key.h
> new file mode 100644
> index 000000000000..b3f8c39cc0e8
> --- /dev/null
> +++ b/include/trace/events/key.h
> @@ -0,0 +1,401 @@

<snip>

> +	    TP_STRUCT__entry(
> +		    __field(key_serial_t,		key)
> +		    __field(uid_t,			uid)
> +		    __array(char,			type, 8)
> +		    __array(char,			desc, 24)
> +			     ),
> +
> +	    TP_fast_assign(
> +		    __entry->key = key->serial;
> +		    __entry->uid = from_kuid(&init_user_ns, key->uid);
> +		    strncpy(__entry->type, key->type->name, sizeof(__entry->type) - 1);
> +		    strncpy(__entry->desc, key->description ?: "", sizeof(__entry->desc) - 1);
> +		    __entry->type[sizeof(__entry->type) - 1] = 0;
> +		    __entry->desc[sizeof(__entry->desc) - 1] = 0;

Looks like these want to be NUL-terminated. Can we use strscpy or
strscpy_pad since strncpy is deprecated [1] for use on NUL-terminated
strings.

> +			   ),
> +
> +	    TP_printk("key=%08x uid=%08x t=%s d=%s",
> +		      __entry->key,
> +		      __entry->uid,
> +		      __entry->type,
> +		      __entry->desc)
> +	    );
> +

<snip>

[1]: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings

Thanks
Justin