EXPORT_SYMBOL(cap_netlink_recv);
+/*
+ * 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)
{
/* Derived from include/linux/sched.h:capable. */
static inline int cap_inh_is_capped(void)
{
/*
- * return 1 if changes to the inheritable set are limited
- * to the old permitted set.
+ * Return 1 if changes to the inheritable set are limited
+ * to the old permitted set. That is, if the current task
+ * does *not* possess the CAP_SETPCAP capability.
*/
- return !cap_capable(current, CAP_SETPCAP);
+ return (cap_capable(current, CAP_SETPCAP) != 0);
}
#else /* ie., ndef CONFIG_SECURITY_FILE_CAPABILITIES */
if (info != SEND_SIG_NOINFO && (is_si_special(info) || SI_FROMKERNEL(info)))
return 0;
+ /*
+ * Running a setuid root program raises your capabilities.
+ * Killing your own setuid root processes was previously
+ * allowed.
+ * We must preserve legacy signal behavior in this case.
+ */
+ if (p->euid == 0 && p->uid == current->uid)
+ return 0;
+
+ /* sigcont is permitted within same session */
+ if (sig == SIGCONT && (task_session_nr(current) == task_session_nr(p)))
+ return 0;
+
if (secid)
/*
* Signal sent as a particular user.