From: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Date: Mon, 17 Apr 2006 11:39:23 +0000 (+0400)
Subject: [PATCH] IPC: access to unmapped vmalloc area in grow_ary()
X-Git-Tag: v2.6.17-rc2~17
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a9a5cd5d2a57fb76dbae2115450f777b69beccf7;p=linux-2.6

[PATCH] IPC: access to unmapped vmalloc area in grow_ary()

grow_ary() should not copy struct ipc_id_ary (it copies new->p, not
new). Due to this, memcpy() src pointer could hit unmapped vmalloc page
when near page boundary.

Found during OpenVZ stress testing

Signed-off-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/ipc/util.c b/ipc/util.c
index 5e785a29e1..b3dcfad3b4 100644
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -183,8 +183,7 @@ static int grow_ary(struct ipc_ids* ids, int newsize)
 	if(new == NULL)
 		return size;
 	new->size = newsize;
-	memcpy(new->p, ids->entries->p, sizeof(struct kern_ipc_perm *)*size +
-					sizeof(struct ipc_id_ary));
+	memcpy(new->p, ids->entries->p, sizeof(struct kern_ipc_perm *)*size);
 	for(i=size;i<newsize;i++) {
 		new->p[i] = NULL;
 	}