merge task_work and rcu_head, get rid of separate allocation for keyring case
task_work and rcu_head are identical now; merge them (calling the result
struct callback_head, rcu_head #define'd to it), kill separate allocation
in security/keys since we can just use cred->rcu now.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/security/keys/internal.h b/security/keys/internal.h
index b510a31..c246ba5 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -148,12 +148,8 @@
#define KEY_LOOKUP_PARTIAL 0x02
#define KEY_LOOKUP_FOR_UNLINK 0x04
-struct kludge { /* this will die off very soon */
- struct task_work twork;
- struct cred *cred;
-};
extern long join_session_keyring(const char *name);
-extern void key_change_session_keyring(struct task_work *twork);
+extern void key_change_session_keyring(struct callback_head *twork);
extern struct work_struct key_gc_work;
extern unsigned key_gc_delay;
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index 26723ca..0291b3f 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -1456,8 +1456,7 @@
{
struct task_struct *me, *parent;
const struct cred *mycred, *pcred;
- struct kludge *newwork;
- struct task_work *oldwork;
+ struct callback_head *newwork, *oldwork;
key_ref_t keyring_r;
struct cred *cred;
int ret;
@@ -1467,20 +1466,17 @@
return PTR_ERR(keyring_r);
ret = -ENOMEM;
- newwork = kmalloc(sizeof(struct kludge), GFP_KERNEL);
- if (!newwork)
- goto error_keyring;
/* our parent is going to need a new cred struct, a new tgcred struct
* and new security data, so we allocate them here to prevent ENOMEM in
* our parent */
cred = cred_alloc_blank();
if (!cred)
- goto error_newwork;
+ goto error_keyring;
+ newwork = &cred->rcu;
cred->tgcred->session_keyring = key_ref_to_ptr(keyring_r);
- init_task_work(&newwork->twork, key_change_session_keyring);
- newwork->cred = cred;
+ init_task_work(newwork, key_change_session_keyring);
me = current;
rcu_read_lock();
@@ -1529,24 +1525,18 @@
/* the replacement session keyring is applied just prior to userspace
* restarting */
- ret = task_work_add(parent, &newwork->twork, true);
+ ret = task_work_add(parent, newwork, true);
if (!ret)
newwork = NULL;
unlock:
write_unlock_irq(&tasklist_lock);
rcu_read_unlock();
- if (oldwork) {
- put_cred(container_of(oldwork, struct kludge, twork)->cred);
- kfree(oldwork);
- }
- if (newwork) {
- put_cred(newwork->cred);
- kfree(newwork);
- }
+ if (oldwork)
+ put_cred(container_of(oldwork, struct cred, rcu));
+ if (newwork)
+ put_cred(cred);
return ret;
-error_newwork:
- kfree(newwork);
error_keyring:
key_ref_put(keyring_r);
return ret;
diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index c9b07c9..54339cf 100644
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -834,13 +834,11 @@
* Replace a process's session keyring on behalf of one of its children when
* the target process is about to resume userspace execution.
*/
-void key_change_session_keyring(struct task_work *twork)
+void key_change_session_keyring(struct callback_head *twork)
{
const struct cred *old = current_cred();
- struct kludge *p = container_of(twork, struct kludge, twork);
- struct cred *new = p->cred;
+ struct cred *new = container_of(twork, struct cred, rcu);
- kfree(p);
if (unlikely(current->flags & PF_EXITING)) {
put_cred(new);
return;
