ring-buffer: Fix wake ups when buffer_percent is set to 100
[platform/kernel/linux-starfive.git] / kernel / cred.c
index 98cb4ec..64404d5 100644 (file)
@@ -43,10 +43,6 @@ static struct group_info init_groups = { .usage = ATOMIC_INIT(2) };
  */
 struct cred init_cred = {
        .usage                  = ATOMIC_INIT(4),
-#ifdef CONFIG_DEBUG_CREDENTIALS
-       .subscribers            = ATOMIC_INIT(2),
-       .magic                  = CRED_MAGIC,
-#endif
        .uid                    = GLOBAL_ROOT_UID,
        .gid                    = GLOBAL_ROOT_GID,
        .suid                   = GLOBAL_ROOT_UID,
@@ -66,31 +62,6 @@ struct cred init_cred = {
        .ucounts                = &init_ucounts,
 };
 
-static inline void set_cred_subscribers(struct cred *cred, int n)
-{
-#ifdef CONFIG_DEBUG_CREDENTIALS
-       atomic_set(&cred->subscribers, n);
-#endif
-}
-
-static inline int read_cred_subscribers(const struct cred *cred)
-{
-#ifdef CONFIG_DEBUG_CREDENTIALS
-       return atomic_read(&cred->subscribers);
-#else
-       return 0;
-#endif
-}
-
-static inline void alter_cred_subscribers(const struct cred *_cred, int n)
-{
-#ifdef CONFIG_DEBUG_CREDENTIALS
-       struct cred *cred = (struct cred *) _cred;
-
-       atomic_add(n, &cred->subscribers);
-#endif
-}
-
 /*
  * The RCU callback to actually dispose of a set of credentials
  */
@@ -100,20 +71,9 @@ static void put_cred_rcu(struct rcu_head *rcu)
 
        kdebug("put_cred_rcu(%p)", cred);
 
-#ifdef CONFIG_DEBUG_CREDENTIALS
-       if (cred->magic != CRED_MAGIC_DEAD ||
-           atomic_read(&cred->usage) != 0 ||
-           read_cred_subscribers(cred) != 0)
-               panic("CRED: put_cred_rcu() sees %p with"
-                     " mag %x, put %p, usage %d, subscr %d\n",
-                     cred, cred->magic, cred->put_addr,
-                     atomic_read(&cred->usage),
-                     read_cred_subscribers(cred));
-#else
-       if (atomic_read(&cred->usage) != 0)
-               panic("CRED: put_cred_rcu() sees %p with usage %d\n",
-                     cred, atomic_read(&cred->usage));
-#endif
+       if (atomic_long_read(&cred->usage) != 0)
+               panic("CRED: put_cred_rcu() sees %p with usage %ld\n",
+                     cred, atomic_long_read(&cred->usage));
 
        security_cred_free(cred);
        key_put(cred->session_keyring);
@@ -137,16 +97,10 @@ static void put_cred_rcu(struct rcu_head *rcu)
  */
 void __put_cred(struct cred *cred)
 {
-       kdebug("__put_cred(%p{%d,%d})", cred,
-              atomic_read(&cred->usage),
-              read_cred_subscribers(cred));
-
-       BUG_ON(atomic_read(&cred->usage) != 0);
-#ifdef CONFIG_DEBUG_CREDENTIALS
-       BUG_ON(read_cred_subscribers(cred) != 0);
-       cred->magic = CRED_MAGIC_DEAD;
-       cred->put_addr = __builtin_return_address(0);
-#endif
+       kdebug("__put_cred(%p{%ld})", cred,
+              atomic_long_read(&cred->usage));
+
+       BUG_ON(atomic_long_read(&cred->usage) != 0);
        BUG_ON(cred == current->cred);
        BUG_ON(cred == current->real_cred);
 
@@ -164,20 +118,15 @@ void exit_creds(struct task_struct *tsk)
 {
        struct cred *cred;
 
-       kdebug("exit_creds(%u,%p,%p,{%d,%d})", tsk->pid, tsk->real_cred, tsk->cred,
-              atomic_read(&tsk->cred->usage),
-              read_cred_subscribers(tsk->cred));
+       kdebug("exit_creds(%u,%p,%p,{%ld})", tsk->pid, tsk->real_cred, tsk->cred,
+              atomic_long_read(&tsk->cred->usage));
 
        cred = (struct cred *) tsk->real_cred;
        tsk->real_cred = NULL;
-       validate_creds(cred);
-       alter_cred_subscribers(cred, -1);
        put_cred(cred);
 
        cred = (struct cred *) tsk->cred;
        tsk->cred = NULL;
-       validate_creds(cred);
-       alter_cred_subscribers(cred, -1);
        put_cred(cred);
 
 #ifdef CONFIG_KEYS_REQUEST_CACHE
@@ -224,10 +173,7 @@ struct cred *cred_alloc_blank(void)
        if (!new)
                return NULL;
 
-       atomic_set(&new->usage, 1);
-#ifdef CONFIG_DEBUG_CREDENTIALS
-       new->magic = CRED_MAGIC;
-#endif
+       atomic_long_set(&new->usage, 1);
        if (security_cred_alloc_blank(new, GFP_KERNEL_ACCOUNT) < 0)
                goto error;
 
@@ -258,8 +204,6 @@ struct cred *prepare_creds(void)
        const struct cred *old;
        struct cred *new;
 
-       validate_process_creds();
-
        new = kmem_cache_alloc(cred_jar, GFP_KERNEL);
        if (!new)
                return NULL;
@@ -270,8 +214,7 @@ struct cred *prepare_creds(void)
        memcpy(new, old, sizeof(struct cred));
 
        new->non_rcu = 0;
-       atomic_set(&new->usage, 1);
-       set_cred_subscribers(new, 0);
+       atomic_long_set(&new->usage, 1);
        get_group_info(new->group_info);
        get_uid(new->user);
        get_user_ns(new->user_ns);
@@ -294,7 +237,6 @@ struct cred *prepare_creds(void)
        if (security_prepare_creds(new, old, GFP_KERNEL_ACCOUNT) < 0)
                goto error;
 
-       validate_creds(new);
        return new;
 
 error:
@@ -357,10 +299,8 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags)
            ) {
                p->real_cred = get_cred(p->cred);
                get_cred(p->cred);
-               alter_cred_subscribers(p->cred, 2);
-               kdebug("share_creds(%p{%d,%d})",
-                      p->cred, atomic_read(&p->cred->usage),
-                      read_cred_subscribers(p->cred));
+               kdebug("share_creds(%p{%ld})",
+                      p->cred, atomic_long_read(&p->cred->usage));
                inc_rlimit_ucounts(task_ucounts(p), UCOUNT_RLIMIT_NPROC, 1);
                return 0;
        }
@@ -399,8 +339,6 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags)
 
        p->cred = p->real_cred = get_cred(new);
        inc_rlimit_ucounts(task_ucounts(p), UCOUNT_RLIMIT_NPROC, 1);
-       alter_cred_subscribers(new, 2);
-       validate_creds(new);
        return 0;
 
 error_put:
@@ -452,17 +390,11 @@ int commit_creds(struct cred *new)
        struct task_struct *task = current;
        const struct cred *old = task->real_cred;
 
-       kdebug("commit_creds(%p{%d,%d})", new,
-              atomic_read(&new->usage),
-              read_cred_subscribers(new));
+       kdebug("commit_creds(%p{%ld})", new,
+              atomic_long_read(&new->usage));
 
        BUG_ON(task->cred != old);
-#ifdef CONFIG_DEBUG_CREDENTIALS
-       BUG_ON(read_cred_subscribers(old) < 2);
-       validate_creds(old);
-       validate_creds(new);
-#endif
-       BUG_ON(atomic_read(&new->usage) < 1);
+       BUG_ON(atomic_long_read(&new->usage) < 1);
 
        get_cred(new); /* we will require a ref for the subj creds too */
 
@@ -497,14 +429,12 @@ int commit_creds(struct cred *new)
         * RLIMIT_NPROC limits on user->processes have already been checked
         * in set_user().
         */
-       alter_cred_subscribers(new, 2);
        if (new->user != old->user || new->user_ns != old->user_ns)
                inc_rlimit_ucounts(new->ucounts, UCOUNT_RLIMIT_NPROC, 1);
        rcu_assign_pointer(task->real_cred, new);
        rcu_assign_pointer(task->cred, new);
        if (new->user != old->user || new->user_ns != old->user_ns)
                dec_rlimit_ucounts(old->ucounts, UCOUNT_RLIMIT_NPROC, 1);
-       alter_cred_subscribers(old, -2);
 
        /* send notifications */
        if (!uid_eq(new->uid,   old->uid)  ||
@@ -535,14 +465,10 @@ EXPORT_SYMBOL(commit_creds);
  */
 void abort_creds(struct cred *new)
 {
-       kdebug("abort_creds(%p{%d,%d})", new,
-              atomic_read(&new->usage),
-              read_cred_subscribers(new));
+       kdebug("abort_creds(%p{%ld})", new,
+              atomic_long_read(&new->usage));
 
-#ifdef CONFIG_DEBUG_CREDENTIALS
-       BUG_ON(read_cred_subscribers(new) != 0);
-#endif
-       BUG_ON(atomic_read(&new->usage) < 1);
+       BUG_ON(atomic_long_read(&new->usage) < 1);
        put_cred(new);
 }
 EXPORT_SYMBOL(abort_creds);
@@ -558,12 +484,8 @@ const struct cred *override_creds(const struct cred *new)
 {
        const struct cred *old = current->cred;
 
-       kdebug("override_creds(%p{%d,%d})", new,
-              atomic_read(&new->usage),
-              read_cred_subscribers(new));
-
-       validate_creds(old);
-       validate_creds(new);
+       kdebug("override_creds(%p{%ld})", new,
+              atomic_long_read(&new->usage));
 
        /*
         * NOTE! This uses 'get_new_cred()' rather than 'get_cred()'.
@@ -572,18 +494,12 @@ const struct cred *override_creds(const struct cred *new)
         * we are only installing the cred into the thread-synchronous
         * '->cred' pointer, not the '->real_cred' pointer that is
         * visible to other threads under RCU.
-        *
-        * Also note that we did validate_creds() manually, not depending
-        * on the validation in 'get_cred()'.
         */
        get_new_cred((struct cred *)new);
-       alter_cred_subscribers(new, 1);
        rcu_assign_pointer(current->cred, new);
-       alter_cred_subscribers(old, -1);
 
-       kdebug("override_creds() = %p{%d,%d}", old,
-              atomic_read(&old->usage),
-              read_cred_subscribers(old));
+       kdebug("override_creds() = %p{%ld}", old,
+              atomic_long_read(&old->usage));
        return old;
 }
 EXPORT_SYMBOL(override_creds);
@@ -599,15 +515,10 @@ void revert_creds(const struct cred *old)
 {
        const struct cred *override = current->cred;
 
-       kdebug("revert_creds(%p{%d,%d})", old,
-              atomic_read(&old->usage),
-              read_cred_subscribers(old));
+       kdebug("revert_creds(%p{%ld})", old,
+              atomic_long_read(&old->usage));
 
-       validate_creds(old);
-       validate_creds(override);
-       alter_cred_subscribers(old, 1);
        rcu_assign_pointer(current->cred, old);
-       alter_cred_subscribers(override, -1);
        put_cred(override);
 }
 EXPORT_SYMBOL(revert_creds);
@@ -727,12 +638,10 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon)
        kdebug("prepare_kernel_cred() alloc %p", new);
 
        old = get_task_cred(daemon);
-       validate_creds(old);
 
        *new = *old;
        new->non_rcu = 0;
-       atomic_set(&new->usage, 1);
-       set_cred_subscribers(new, 0);
+       atomic_long_set(&new->usage, 1);
        get_uid(new->user);
        get_user_ns(new->user_ns);
        get_group_info(new->group_info);
@@ -756,7 +665,6 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon)
                goto error;
 
        put_cred(old);
-       validate_creds(new);
        return new;
 
 error:
@@ -821,109 +729,3 @@ int set_create_files_as(struct cred *new, struct inode *inode)
        return security_kernel_create_files_as(new, inode);
 }
 EXPORT_SYMBOL(set_create_files_as);
-
-#ifdef CONFIG_DEBUG_CREDENTIALS
-
-bool creds_are_invalid(const struct cred *cred)
-{
-       if (cred->magic != CRED_MAGIC)
-               return true;
-       return false;
-}
-EXPORT_SYMBOL(creds_are_invalid);
-
-/*
- * dump invalid credentials
- */
-static void dump_invalid_creds(const struct cred *cred, const char *label,
-                              const struct task_struct *tsk)
-{
-       pr_err("%s credentials: %p %s%s%s\n",
-              label, cred,
-              cred == &init_cred ? "[init]" : "",
-              cred == tsk->real_cred ? "[real]" : "",
-              cred == tsk->cred ? "[eff]" : "");
-       pr_err("->magic=%x, put_addr=%p\n",
-              cred->magic, cred->put_addr);
-       pr_err("->usage=%d, subscr=%d\n",
-              atomic_read(&cred->usage),
-              read_cred_subscribers(cred));
-       pr_err("->*uid = { %d,%d,%d,%d }\n",
-               from_kuid_munged(&init_user_ns, cred->uid),
-               from_kuid_munged(&init_user_ns, cred->euid),
-               from_kuid_munged(&init_user_ns, cred->suid),
-               from_kuid_munged(&init_user_ns, cred->fsuid));
-       pr_err("->*gid = { %d,%d,%d,%d }\n",
-               from_kgid_munged(&init_user_ns, cred->gid),
-               from_kgid_munged(&init_user_ns, cred->egid),
-               from_kgid_munged(&init_user_ns, cred->sgid),
-               from_kgid_munged(&init_user_ns, cred->fsgid));
-#ifdef CONFIG_SECURITY
-       pr_err("->security is %p\n", cred->security);
-       if ((unsigned long) cred->security >= PAGE_SIZE &&
-           (((unsigned long) cred->security & 0xffffff00) !=
-            (POISON_FREE << 24 | POISON_FREE << 16 | POISON_FREE << 8)))
-               pr_err("->security {%x, %x}\n",
-                      ((u32*)cred->security)[0],
-                      ((u32*)cred->security)[1]);
-#endif
-}
-
-/*
- * report use of invalid credentials
- */
-void __noreturn __invalid_creds(const struct cred *cred, const char *file, unsigned line)
-{
-       pr_err("Invalid credentials\n");
-       pr_err("At %s:%u\n", file, line);
-       dump_invalid_creds(cred, "Specified", current);
-       BUG();
-}
-EXPORT_SYMBOL(__invalid_creds);
-
-/*
- * check the credentials on a process
- */
-void __validate_process_creds(struct task_struct *tsk,
-                             const char *file, unsigned line)
-{
-       if (tsk->cred == tsk->real_cred) {
-               if (unlikely(read_cred_subscribers(tsk->cred) < 2 ||
-                            creds_are_invalid(tsk->cred)))
-                       goto invalid_creds;
-       } else {
-               if (unlikely(read_cred_subscribers(tsk->real_cred) < 1 ||
-                            read_cred_subscribers(tsk->cred) < 1 ||
-                            creds_are_invalid(tsk->real_cred) ||
-                            creds_are_invalid(tsk->cred)))
-                       goto invalid_creds;
-       }
-       return;
-
-invalid_creds:
-       pr_err("Invalid process credentials\n");
-       pr_err("At %s:%u\n", file, line);
-
-       dump_invalid_creds(tsk->real_cred, "Real", tsk);
-       if (tsk->cred != tsk->real_cred)
-               dump_invalid_creds(tsk->cred, "Effective", tsk);
-       else
-               pr_err("Effective creds == Real creds\n");
-       BUG();
-}
-EXPORT_SYMBOL(__validate_process_creds);
-
-/*
- * check creds for do_exit()
- */
-void validate_creds_for_do_exit(struct task_struct *tsk)
-{
-       kdebug("validate_creds_for_do_exit(%p,%p{%d,%d})",
-              tsk->real_cred, tsk->cred,
-              atomic_read(&tsk->cred->usage),
-              read_cred_subscribers(tsk->cred));
-
-       __validate_process_creds(tsk, __FILE__, __LINE__);
-}
-
-#endif /* CONFIG_DEBUG_CREDENTIALS */