$NetBSD: patch-ar,v 1.6 2007/06/28 00:43:36 lkundrak Exp $

Fix for CVE-2007-1863 remote crash when mod_cache enabled.

--- src/main/http_main.c.orig	2007-06-28 02:10:30.000000000 +0200
+++ src/main/http_main.c
@@ -2751,6 +2751,17 @@ static int find_child_by_pid(int pid)
     return -1;
 }
 
+static int safe_child_kill(pid_t pid, int sig)
+{
+    if (getpgid(pid) == getpgrp()) {
+        return kill(pid, sig);
+    }
+    else {
+        errno = EINVAL;
+        return -1;
+    }
+}
+
 static void reclaim_child_processes(int terminate)
 {
 #ifndef MULTITHREAD
@@ -5113,7 +5124,7 @@ static void perform_idle_server_maintena
 		else if (ps->last_rtime + ss->timeout_len < now) {
 		    /* no progress, and the timeout length has been exceeded */
 		    ss->timeout_len = 0;
-		    kill(ps->pid, SIG_TIMEOUT_KILL);
+		    safe_child_kill(ps->pid, SIG_TIMEOUT_KILL);
 		}
 	    }
 #endif
@@ -5126,7 +5137,7 @@ static void perform_idle_server_maintena
 	 * while we were counting. Use the define SIG_IDLE_KILL to reflect
 	 * which signal should be used on the specific OS.
 	 */
-	kill(ap_scoreboard_image->parent[to_kill].pid, SIG_IDLE_KILL);
+	safe_child_kill(ap_scoreboard_image->parent[to_kill].pid, SIG_IDLE_KILL);
 	idle_spawn_rate = 1;
 #ifdef TPF
         ap_update_child_status(to_kill, SERVER_DEAD, (request_rec *)NULL);