KEYS: Add an RCU payload dereference macro
Add an RCU payload dereference macro as this seems to be a common piece of code
amongst key types that use RCU referenced payloads.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/include/linux/key.h b/include/linux/key.h
index 3db0adc..a6b1edc 100644
--- a/include/linux/key.h
+++ b/include/linux/key.h
@@ -275,6 +275,10 @@
return key ? key->serial : 0;
}
+#define rcu_dereference_key(KEY) \
+ (rcu_dereference_protected((KEY)->payload.rcudata, \
+ rwsem_is_locked(&((struct key *)(KEY))->sem)))
+
#ifdef CONFIG_SYSCTL
extern ctl_table key_sysctls[];
#endif
diff --git a/security/keys/encrypted.c b/security/keys/encrypted.c
index 9e7e4ce..69907a5 100644
--- a/security/keys/encrypted.c
+++ b/security/keys/encrypted.c
@@ -765,8 +765,7 @@
size_t asciiblob_len;
int ret;
- epayload = rcu_dereference_protected(key->payload.data,
- rwsem_is_locked(&((struct key *)key)->sem));
+ epayload = rcu_dereference_key(key);
/* returns the hex encoded iv, encrypted-data, and hmac as ascii */
asciiblob_len = epayload->datablob_len + ivsize + 1
diff --git a/security/keys/trusted.c b/security/keys/trusted.c
index 83fc92e..c99b936 100644
--- a/security/keys/trusted.c
+++ b/security/keys/trusted.c
@@ -1076,8 +1076,7 @@
char *bufp;
int i;
- p = rcu_dereference_protected(key->payload.data,
- rwsem_is_locked(&((struct key *)key)->sem));
+ p = rcu_dereference_key(key);
if (!p)
return -EINVAL;
if (!buffer || buflen <= 0)
diff --git a/security/keys/user_defined.c b/security/keys/user_defined.c
index 02807fb..c6ca866 100644
--- a/security/keys/user_defined.c
+++ b/security/keys/user_defined.c
@@ -184,8 +184,7 @@
struct user_key_payload *upayload;
long ret;
- upayload = rcu_dereference_protected(
- key->payload.data, rwsem_is_locked(&((struct key *)key)->sem));
+ upayload = rcu_dereference_key(key);
ret = upayload->datalen;
/* we can return the data as is */
