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-rw-r--r--include/linux/capability.h17
-rw-r--r--include/linux/security.h49
-rw-r--r--kernel/capability.c2
-rw-r--r--security/capability.c1
-rw-r--r--security/commoncap.c42
-rw-r--r--security/root_plug.c1
-rw-r--r--security/security.c25
-rw-r--r--security/selinux/hooks.c26
-rw-r--r--security/smack/smack_lsm.c1
9 files changed, 129 insertions, 35 deletions
diff --git a/include/linux/capability.h b/include/linux/capability.h
index e22f48c2a46..5b8a1321445 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_task_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_task_capable_noaudit((t), (cap)) == 0)
extern int capable(int cap);
diff --git a/include/linux/security.h b/include/linux/security.h
index 3416cb85e77..76989b8bc34 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -48,7 +48,9 @@ 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(int cap, int audit);
+extern int cap_task_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 +1197,18 @@ 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 current process has the @cap capability in its
+ * subjective/effective credentials.
+ * @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.
+ * @task_capable:
+ * Check whether the @tsk process has the @cap capability in its
+ * objective/real 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 +1301,9 @@ 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) (int cap, int audit);
+ int (*task_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 +1569,9 @@ 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_task_capable(struct task_struct *tsk, int cap);
+int security_task_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 +1768,31 @@ 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(cap, SECURITY_CAP_AUDIT);
}
-static inline int security_capable_noaudit(struct task_struct *tsk, int cap)
+static inline int security_task_capable(struct task_struct *tsk, int cap)
{
- return cap_capable(tsk, cap, SECURITY_CAP_NOAUDIT);
+ int ret;
+
+ rcu_read_lock();
+ ret = cap_task_capable(tsk, __task_cred(tsk), cap, SECURITY_CAP_AUDIT);
+ rcu_read_unlock();
+ return ret;
+}
+
+static inline
+int security_task_capable_noaudit(struct task_struct *tsk, int cap)
+{
+ int ret;
+
+ rcu_read_lock();
+ ret = cap_task_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 36b4b4daebe..df62f53f84a 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/capability.c b/security/capability.c
index 2dce66fcb99..fd1493da4f8 100644
--- a/security/capability.c
+++ b/security/capability.c
@@ -826,6 +826,7 @@ void security_fixup_ops(struct security_operations *ops)
set_to_cap_if_null(ops, capset);
set_to_cap_if_null(ops, acct);
set_to_cap_if_null(ops, capable);
+ set_to_cap_if_null(ops, task_capable);
set_to_cap_if_null(ops, quotactl);
set_to_cap_if_null(ops, quota_on);
set_to_cap_if_null(ops, sysctl);
diff --git a/security/commoncap.c b/security/commoncap.c
index 79713545cd6..7f0b2a68717 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -43,28 +43,44 @@ int cap_netlink_recv(struct sk_buff *skb, int cap)
EXPORT_SYMBOL(cap_netlink_recv);
/**
- * cap_capable - Determine whether a task has a particular effective capability
- * @tsk: The task to query
+ * cap_capable - Determine whether current has a particular effective capability
* @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.
+ * its effective set, returning 0 if it does, -ve if it does not. Note that
+ * this uses current's subjective/effective credentials.
*
* 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.
*/
-int cap_capable(struct task_struct *tsk, int cap, int audit)
+int cap_capable(int cap, int audit)
{
- __u32 cap_raised;
+ return cap_raised(current_cap(), cap) ? 0 : -EPERM;
+}
- /* 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;
+/**
+ * cap_has_capability - 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 that
+ * this uses the task's objective/real credentials.
+ *
+ * NOTE WELL: cap_has_capability() cannot be used like the kernel's
+ * has_capability() function. That is, it has the reverse semantics:
+ * cap_has_capability() returns 0 when a task has a capability, but the
+ * kernel's has_capability() returns 1 for this case.
+ */
+int cap_task_capable(struct task_struct *tsk, const struct cred *cred, int cap,
+ int audit)
+{
+ return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM;
}
/**
@@ -160,7 +176,7 @@ 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(CAP_SETPCAP, SECURITY_CAP_AUDIT) == 0)
return 0;
#endif
return 1;
@@ -869,7 +885,7 @@ 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(CAP_SETPCAP, SECURITY_CAP_AUDIT) != 0) /*[4]*/
/*
* [1] no changing of bits that are locked
* [2] no unlocking of locks
@@ -950,7 +966,7 @@ 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(CAP_SYS_ADMIN, SECURITY_CAP_NOAUDIT) == 0)
cap_sys_admin = 1;
return __vm_enough_memory(mm, pages, cap_sys_admin);
}
diff --git a/security/root_plug.c b/security/root_plug.c
index 40fb4f15e27..559578f8ac6 100644
--- a/security/root_plug.c
+++ b/security/root_plug.c
@@ -77,6 +77,7 @@ static struct security_operations rootplug_security_ops = {
.capget = cap_capget,
.capset = cap_capset,
.capable = cap_capable,
+ .task_capable = cap_task_capable,
.bprm_set_creds = cap_bprm_set_creds,
diff --git a/security/security.c b/security/security.c
index d85dbb37c97..9bbc8e57b8c 100644
--- a/security/security.c
+++ b/security/security.c
@@ -154,14 +154,31 @@ 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(cap, SECURITY_CAP_AUDIT);
}
-int security_capable_noaudit(struct task_struct *tsk, int cap)
+int security_task_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->task_capable(tsk, cred, cap, SECURITY_CAP_AUDIT);
+ put_cred(cred);
+ return ret;
+}
+
+int security_task_capable_noaudit(struct task_struct *tsk, int cap)
+{
+ const struct cred *cred;
+ int ret;
+
+ cred = get_task_cred(tsk);
+ ret = security_ops->task_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 df30a7555d8..eb6c45107a0 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 +1866,27 @@ 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(int cap, int audit)
+{
+ int rc;
+
+ rc = secondary_ops->capable(cap, audit);
+ if (rc)
+ return rc;
+
+ return task_has_capability(current, current_cred(), cap, audit);
+}
+
+static int selinux_task_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->task_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 +2050,7 @@ 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(CAP_SYS_ADMIN, SECURITY_CAP_NOAUDIT);
if (rc == 0)
cap_sys_admin = 1;
@@ -2880,7 +2893,7 @@ 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(CAP_MAC_ADMIN, SECURITY_CAP_NOAUDIT);
if (!error)
error = security_sid_to_context_force(isec->sid, &context,
&size);
@@ -5568,6 +5581,7 @@ static struct security_operations selinux_ops = {
.capset = selinux_capset,
.sysctl = selinux_sysctl,
.capable = selinux_capable,
+ .task_capable = selinux_task_capable,
.quotactl = selinux_quotactl,
.quota_on = selinux_quota_on,
.syslog = selinux_syslog,
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 6bfaba6177c..7f12cc7015b 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -2827,6 +2827,7 @@ struct security_operations smack_ops = {
.capget = cap_capget,
.capset = cap_capset,
.capable = cap_capable,
+ .task_capable = cap_task_capable,
.syslog = smack_syslog,
.settime = cap_settime,
.vm_enough_memory = cap_vm_enough_memory,