From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1162516Ab3LFXjZ (ORCPT ); Fri, 6 Dec 2013 18:39:25 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:48719 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161567Ab3LFXSI (ORCPT ); Fri, 6 Dec 2013 18:18:08 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Peter Hurley , Andrew Morton , Linus Torvalds , Kamal Mostafa Subject: [PATCH 3.8 112/152] ipc: tighten msg copy loops Date: Fri, 6 Dec 2013 15:10:36 -0800 Message-Id: <1386371476-2477-113-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1386371476-2477-1-git-send-email-kamal@canonical.com> References: <1386371476-2477-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.8.13.14 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Peter Hurley commit da085d4591a6fe11eac2e1f659f25b655e9f2e53 upstream. Signed-off-by: Peter Hurley Acked-by: Stanislav Kinsbursky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds [ kamal: 3.8 stable prereq for 4e9b45a ipc, msg: fix message length check for negative values ] Signed-off-by: Kamal Mostafa --- ipc/msgutil.c | 32 +++++++++++--------------------- 1 file changed, 11 insertions(+), 21 deletions(-) diff --git a/ipc/msgutil.c b/ipc/msgutil.c index 0a5c8a9..b79582d 100644 --- a/ipc/msgutil.c +++ b/ipc/msgutil.c @@ -97,18 +97,14 @@ struct msg_msg *load_msg(const void __user *src, int len) goto out_err; } - len -= alen; - src = ((char __user *)src) + alen; - seg = msg->next; - while (len > 0) { + for (seg = msg->next; seg != NULL; seg = seg->next) { + len -= alen; + src = (char __user *)src + alen; alen = min(len, DATALEN_SEG); if (copy_from_user(seg + 1, src, alen)) { err = -EFAULT; goto out_err; } - seg = seg->next; - len -= alen; - src = ((char __user *)src) + alen; } err = security_msg_msg_alloc(msg); @@ -135,15 +131,13 @@ struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst) alen = min(len, DATALEN_MSG); memcpy(dst + 1, src + 1, alen); - len -= alen; - dst_pseg = dst->next; - src_pseg = src->next; - while (len > 0) { + for (dst_pseg = dst->next, src_pseg = src->next; + src_pseg != NULL; + dst_pseg = dst_pseg->next, src_pseg = src_pseg->next) { + + len -= alen; alen = min(len, DATALEN_SEG); memcpy(dst_pseg + 1, src_pseg + 1, alen); - dst_pseg = dst_pseg->next; - len -= alen; - src_pseg = src_pseg->next; } dst->m_type = src->m_type; @@ -166,16 +160,12 @@ int store_msg(void __user *dest, struct msg_msg *msg, int len) if (copy_to_user(dest, msg + 1, alen)) return -1; - len -= alen; - dest = ((char __user *)dest) + alen; - seg = msg->next; - while (len > 0) { + for (seg = msg->next; seg != NULL; seg = seg->next) { + len -= alen; + dest = (char __user *)dest + alen; alen = min(len, DATALEN_SEG); if (copy_to_user(dest, seg + 1, alen)) return -1; - len -= alen; - dest = ((char __user *)dest) + alen; - seg = seg->next; } return 0; } -- 1.8.3.2