[PATCH] refactor capable() to one implementation, add __capable() helper
Move capable() to kernel/capability.c and eliminate duplicate
implementations. Add __capable() function which can be used to check for
capabiilty of any process.
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/capability.h b/include/linux/capability.h
index 5a23ce7..6548b35 100644
--- a/include/linux/capability.h
+++ b/include/linux/capability.h
@@ -357,7 +357,8 @@
#define cap_is_fs_cap(c) (CAP_TO_MASK(c) & CAP_FS_MASK)
-extern int capable(int cap);
+int capable(int cap);
+int __capable(struct task_struct *t, int cap);
#endif /* __KERNEL__ */
diff --git a/include/linux/security.h b/include/linux/security.h
index b18eb8c..3c19be3 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -1040,6 +1040,11 @@
* @effective contains the effective capability set.
* @inheritable contains the inheritable capability set.
* @permitted contains the permitted capability set.
+ * @capable:
+ * Check whether the @tsk process has the @cap capability.
+ * @tsk contains the task_struct for the process.
+ * @cap contains the capability <include/linux/capability.h>.
+ * Return 0 if the capability is granted for @tsk.
* @acct:
* Check permission before enabling or disabling process accounting. If
* accounting is being enabled, then @file refers to the open file used to
@@ -1053,11 +1058,6 @@
* @table contains the ctl_table structure for the sysctl variable.
* @op contains the operation (001 = search, 002 = write, 004 = read).
* Return 0 if permission is granted.
- * @capable:
- * Check whether the @tsk process has the @cap capability.
- * @tsk contains the task_struct for the process.
- * @cap contains the capability <include/linux/capability.h>.
- * Return 0 if the capability is granted for @tsk.
* @syslog:
* Check permission before accessing the kernel message ring or changing
* logging to the console.
@@ -1099,9 +1099,9 @@
kernel_cap_t * effective,
kernel_cap_t * inheritable,
kernel_cap_t * permitted);
+ int (*capable) (struct task_struct * tsk, int cap);
int (*acct) (struct file * file);
int (*sysctl) (struct ctl_table * table, int op);
- int (*capable) (struct task_struct * tsk, int cap);
int (*quotactl) (int cmds, int type, int id, struct super_block * sb);
int (*quota_on) (struct dentry * dentry);
int (*syslog) (int type);
@@ -1347,6 +1347,11 @@
security_ops->capset_set (target, effective, inheritable, permitted);
}
+static inline int security_capable(struct task_struct *tsk, int cap)
+{
+ return security_ops->capable(tsk, cap);
+}
+
static inline int security_acct (struct file *file)
{
return security_ops->acct (file);
@@ -2050,6 +2055,11 @@
cap_capset_set (target, effective, inheritable, permitted);
}
+static inline int security_capable(struct task_struct *tsk, int cap)
+{
+ return cap_capable(tsk, cap);
+}
+
static inline int security_acct (struct file *file)
{
return 0;
diff --git a/kernel/capability.c b/kernel/capability.c
index bfa3c92..1a4d8a4 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -233,3 +233,19 @@
return ret;
}
+
+int __capable(struct task_struct *t, int cap)
+{
+ if (security_capable(t, cap) == 0) {
+ t->flags |= PF_SUPERPRIV;
+ return 1;
+ }
+ return 0;
+}
+EXPORT_SYMBOL(__capable);
+
+int capable(int cap)
+{
+ return __capable(current, cap);
+}
+EXPORT_SYMBOL(capable);
diff --git a/kernel/sys.c b/kernel/sys.c
index 19d058b..421009c 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -224,18 +224,6 @@
EXPORT_SYMBOL(unregister_reboot_notifier);
-#ifndef CONFIG_SECURITY
-int capable(int cap)
-{
- if (cap_raised(current->cap_effective, cap)) {
- current->flags |= PF_SUPERPRIV;
- return 1;
- }
- return 0;
-}
-EXPORT_SYMBOL(capable);
-#endif
-
static int set_one_prio(struct task_struct *p, int niceval, int error)
{
int no_nice;
diff --git a/security/security.c b/security/security.c
index f693e1f..51ef509 100644
--- a/security/security.c
+++ b/security/security.c
@@ -174,31 +174,8 @@
return security_ops->unregister_security(name, ops);
}
-/**
- * capable - calls the currently loaded security module's capable() function with the specified capability
- * @cap: the requested capability level.
- *
- * This function calls the currently loaded security module's capable()
- * function with a pointer to the current task and the specified @cap value.
- *
- * This allows the security module to implement the capable function call
- * however it chooses to.
- */
-int capable(int cap)
-{
- if (security_ops->capable(current, cap)) {
- /* capability denied */
- return 0;
- }
-
- /* capability granted */
- current->flags |= PF_SUPERPRIV;
- return 1;
-}
-
EXPORT_SYMBOL_GPL(register_security);
EXPORT_SYMBOL_GPL(unregister_security);
EXPORT_SYMBOL_GPL(mod_reg_security);
EXPORT_SYMBOL_GPL(mod_unreg_security);
-EXPORT_SYMBOL(capable);
EXPORT_SYMBOL(security_ops);