diff --git a/security/commoncap.c b/security/commoncap.c index 302e8d0839a9..5bc1895f3f9c 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -526,6 +526,15 @@ int cap_task_kill(struct task_struct *p, struct siginfo *info, 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;