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-rw-r--r--include/linux/capability.h17
-rw-r--r--include/linux/security.h41
-rw-r--r--kernel/capability.c2
-rw-r--r--security/commoncap.c29
-rw-r--r--security/security.c26
-rw-r--r--security/selinux/hooks.c16
6 files changed, 94 insertions, 37 deletions
diff --git a/include/linux/capability.h b/include/linux/capability.h
index e22f48c..02bdb76 100644
--- a/include/linux/capability.h
+++ b/include/linux/capability.h
@@ -529,8 +529,21 @@ extern const kernel_cap_t __cap_init_eff_set;
*
* Note that this does not set PF_SUPERPRIV on the task.
*/
-#define has_capability(t, cap) (security_capable((t), (cap)) == 0)
-#define has_capability_noaudit(t, cap) (security_capable_noaudit((t), (cap)) == 0)
+#define has_capability(t, cap) (security_real_capable((t), (cap)) == 0)
+
+/**
+ * has_capability_noaudit - Determine if a task has a superior capability available (unaudited)
+ * @t: The task in question
+ * @cap: The capability to be tested for
+ *
+ * Return true if the specified task has the given superior capability
+ * currently in effect, false if not, but don't write an audit message for the
+ * check.
+ *
+ * Note that this does not set PF_SUPERPRIV on the task.
+ */
+#define has_capability_noaudit(t, cap) \
+ (security_real_capable_noaudit((t), (cap)) == 0)
extern int capable(int cap);
diff --git a/include/linux/security.h b/include/linux/security.h
index 3416cb8..f9c3904 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -48,7 +48,8 @@ struct audit_krule;
* These functions are in security/capability.c and are used
* as the default capabilities functions
*/
-extern int cap_capable(struct task_struct *tsk, int cap, int audit);
+extern int cap_capable(struct task_struct *tsk, const struct cred *cred,
+ int cap, int audit);
extern int cap_settime(struct timespec *ts, struct timezone *tz);
extern int cap_ptrace_may_access(struct task_struct *child, unsigned int mode);
extern int cap_ptrace_traceme(struct task_struct *parent);
@@ -1195,9 +1196,12 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts)
* @permitted contains the permitted capability set.
* Return 0 and update @new if permission is granted.
* @capable:
- * Check whether the @tsk process has the @cap capability.
+ * Check whether the @tsk process has the @cap capability in the indicated
+ * credentials.
* @tsk contains the task_struct for the process.
+ * @cred contains the credentials to use.
* @cap contains the capability <include/linux/capability.h>.
+ * @audit: Whether to write an audit message or not
* Return 0 if the capability is granted for @tsk.
* @acct:
* Check permission before enabling or disabling process accounting. If
@@ -1290,7 +1294,8 @@ struct security_operations {
const kernel_cap_t *effective,
const kernel_cap_t *inheritable,
const kernel_cap_t *permitted);
- int (*capable) (struct task_struct *tsk, int cap, int audit);
+ int (*capable) (struct task_struct *tsk, const struct cred *cred,
+ int cap, int audit);
int (*acct) (struct file *file);
int (*sysctl) (struct ctl_table *table, int op);
int (*quotactl) (int cmds, int type, int id, struct super_block *sb);
@@ -1556,8 +1561,9 @@ int security_capset(struct cred *new, const struct cred *old,
const kernel_cap_t *effective,
const kernel_cap_t *inheritable,
const kernel_cap_t *permitted);
-int security_capable(struct task_struct *tsk, int cap);
-int security_capable_noaudit(struct task_struct *tsk, int cap);
+int security_capable(int cap);
+int security_real_capable(struct task_struct *tsk, int cap);
+int security_real_capable_noaudit(struct task_struct *tsk, int cap);
int security_acct(struct file *file);
int security_sysctl(struct ctl_table *table, int op);
int security_quotactl(int cmds, int type, int id, struct super_block *sb);
@@ -1754,14 +1760,31 @@ static inline int security_capset(struct cred *new,
return cap_capset(new, old, effective, inheritable, permitted);
}
-static inline int security_capable(struct task_struct *tsk, int cap)
+static inline int security_capable(int cap)
{
- return cap_capable(tsk, cap, SECURITY_CAP_AUDIT);
+ return cap_capable(current, current_cred(), cap, SECURITY_CAP_AUDIT);
}
-static inline int security_capable_noaudit(struct task_struct *tsk, int cap)
+static inline int security_real_capable(struct task_struct *tsk, int cap)
{
- return cap_capable(tsk, cap, SECURITY_CAP_NOAUDIT);
+ int ret;
+
+ rcu_read_lock();
+ ret = cap_capable(tsk, __task_cred(tsk), cap, SECURITY_CAP_AUDIT);
+ rcu_read_unlock();
+ return ret;
+}
+
+static inline
+int security_real_capable_noaudit(struct task_struct *tsk, int cap)
+{
+ int ret;
+
+ rcu_read_lock();
+ ret = cap_capable(tsk, __task_cred(tsk), cap,
+ SECURITY_CAP_NOAUDIT);
+ rcu_read_unlock();
+ return ret;
}
static inline int security_acct(struct file *file)
diff --git a/kernel/capability.c b/kernel/capability.c
index 36b4b4d..df62f53 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -308,7 +308,7 @@ int capable(int cap)
BUG();
}
- if (has_capability(current, cap)) {
+ if (security_capable(cap) == 0) {
current->flags |= PF_SUPERPRIV;
return 1;
}
diff --git a/security/commoncap.c b/security/commoncap.c
index 7971354..f0e671d 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -45,26 +45,22 @@ EXPORT_SYMBOL(cap_netlink_recv);
/**
* cap_capable - Determine whether a task has a particular effective capability
* @tsk: The task to query
+ * @cred: The credentials to use
* @cap: The capability to check for
* @audit: Whether to write an audit message or not
*
* Determine whether the nominated task has the specified capability amongst
* its effective set, returning 0 if it does, -ve if it does not.
*
- * NOTE WELL: cap_capable() cannot be used like the kernel's capable()
- * function. That is, it has the reverse semantics: cap_capable() returns 0
- * when a task has a capability, but the kernel's capable() returns 1 for this
- * case.
+ * NOTE WELL: cap_has_capability() cannot be used like the kernel's capable()
+ * and has_capability() functions. That is, it has the reverse semantics:
+ * cap_has_capability() returns 0 when a task has a capability, but the
+ * kernel's capable() and has_capability() returns 1 for this case.
*/
-int cap_capable(struct task_struct *tsk, int cap, int audit)
+int cap_capable(struct task_struct *tsk, const struct cred *cred, int cap,
+ int audit)
{
- __u32 cap_raised;
-
- /* Derived from include/linux/sched.h:capable. */
- rcu_read_lock();
- cap_raised = cap_raised(__task_cred(tsk)->cap_effective, cap);
- rcu_read_unlock();
- return cap_raised ? 0 : -EPERM;
+ return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM;
}
/**
@@ -160,7 +156,8 @@ static inline int cap_inh_is_capped(void)
/* they are so limited unless the current task has the CAP_SETPCAP
* capability
*/
- if (cap_capable(current, CAP_SETPCAP, SECURITY_CAP_AUDIT) == 0)
+ if (cap_capable(current, current_cred(), CAP_SETPCAP,
+ SECURITY_CAP_AUDIT) == 0)
return 0;
#endif
return 1;
@@ -869,7 +866,8 @@ int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3,
& (new->securebits ^ arg2)) /*[1]*/
|| ((new->securebits & SECURE_ALL_LOCKS & ~arg2)) /*[2]*/
|| (arg2 & ~(SECURE_ALL_LOCKS | SECURE_ALL_BITS)) /*[3]*/
- || (cap_capable(current, CAP_SETPCAP, SECURITY_CAP_AUDIT) != 0) /*[4]*/
+ || (cap_capable(current, current_cred(), CAP_SETPCAP,
+ SECURITY_CAP_AUDIT) != 0) /*[4]*/
/*
* [1] no changing of bits that are locked
* [2] no unlocking of locks
@@ -950,7 +948,8 @@ int cap_vm_enough_memory(struct mm_struct *mm, long pages)
{
int cap_sys_admin = 0;
- if (cap_capable(current, CAP_SYS_ADMIN, SECURITY_CAP_NOAUDIT) == 0)
+ if (cap_capable(current, current_cred(), CAP_SYS_ADMIN,
+ SECURITY_CAP_NOAUDIT) == 0)
cap_sys_admin = 1;
return __vm_enough_memory(mm, pages, cap_sys_admin);
}
diff --git a/security/security.c b/security/security.c
index d85dbb3..a02f243 100644
--- a/security/security.c
+++ b/security/security.c
@@ -154,14 +154,32 @@ int security_capset(struct cred *new, const struct cred *old,
effective, inheritable, permitted);
}
-int security_capable(struct task_struct *tsk, int cap)
+int security_capable(int cap)
{
- return security_ops->capable(tsk, cap, SECURITY_CAP_AUDIT);
+ return security_ops->capable(current, current_cred(), cap,
+ SECURITY_CAP_AUDIT);
}
-int security_capable_noaudit(struct task_struct *tsk, int cap)
+int security_real_capable(struct task_struct *tsk, int cap)
{
- return security_ops->capable(tsk, cap, SECURITY_CAP_NOAUDIT);
+ const struct cred *cred;
+ int ret;
+
+ cred = get_task_cred(tsk);
+ ret = security_ops->capable(tsk, cred, cap, SECURITY_CAP_AUDIT);
+ put_cred(cred);
+ return ret;
+}
+
+int security_real_capable_noaudit(struct task_struct *tsk, int cap)
+{
+ const struct cred *cred;
+ int ret;
+
+ cred = get_task_cred(tsk);
+ ret = security_ops->capable(tsk, cred, cap, SECURITY_CAP_NOAUDIT);
+ put_cred(cred);
+ return ret;
}
int security_acct(struct file *file)
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index df30a75..0081597 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -1433,12 +1433,13 @@ static int current_has_perm(const struct task_struct *tsk,
/* Check whether a task is allowed to use a capability. */
static int task_has_capability(struct task_struct *tsk,
+ const struct cred *cred,
int cap, int audit)
{
struct avc_audit_data ad;
struct av_decision avd;
u16 sclass;
- u32 sid = task_sid(tsk);
+ u32 sid = cred_sid(cred);
u32 av = CAP_TO_MASK(cap);
int rc;
@@ -1865,15 +1866,16 @@ static int selinux_capset(struct cred *new, const struct cred *old,
return cred_has_perm(old, new, PROCESS__SETCAP);
}
-static int selinux_capable(struct task_struct *tsk, int cap, int audit)
+static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
+ int cap, int audit)
{
int rc;
- rc = secondary_ops->capable(tsk, cap, audit);
+ rc = secondary_ops->capable(tsk, cred, cap, audit);
if (rc)
return rc;
- return task_has_capability(tsk, cap, audit);
+ return task_has_capability(tsk, cred, cap, audit);
}
static int selinux_sysctl_get_sid(ctl_table *table, u16 tclass, u32 *sid)
@@ -2037,7 +2039,8 @@ static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
{
int rc, cap_sys_admin = 0;
- rc = selinux_capable(current, CAP_SYS_ADMIN, SECURITY_CAP_NOAUDIT);
+ rc = selinux_capable(current, current_cred(), CAP_SYS_ADMIN,
+ SECURITY_CAP_NOAUDIT);
if (rc == 0)
cap_sys_admin = 1;
@@ -2880,7 +2883,8 @@ static int selinux_inode_getsecurity(const struct inode *inode, const char *name
* and lack of permission just means that we fall back to the
* in-core context value, not a denial.
*/
- error = selinux_capable(current, CAP_MAC_ADMIN, SECURITY_CAP_NOAUDIT);
+ error = selinux_capable(current, current_cred(), CAP_MAC_ADMIN,
+ SECURITY_CAP_NOAUDIT);
if (!error)
error = security_sid_to_context_force(isec->sid, &context,
&size);
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