From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Peter Hurley , Stanislav Kinsbursky , Andrew Morton , Linus Torvalds Subject: [ 058/100] ipc: dont allocate a copy larger than max Date: Tue, 12 Mar 2013 15:31:43 -0700 Message-Id: <20130312223129.241562840@linuxfoundation.org> In-Reply-To: <20130312223122.884099393@linuxfoundation.org> References: <20130312223122.884099393@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Peter Hurley commit 88b9e456b1649722673ffa147914299799dc9041 upstream. When MSG_COPY is set, a duplicate message must be allocated for the copy before locking the queue. However, the copy could not be larger than was sent which is limited to msg_ctlmax. Signed-off-by: Peter Hurley Acked-by: Stanislav Kinsbursky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- ipc/msg.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/ipc/msg.c +++ b/ipc/msg.c @@ -820,15 +820,17 @@ long do_msgrcv(int msqid, void __user *b struct msg_msg *copy = NULL; unsigned long copy_number = 0; + ns = current->nsproxy->ipc_ns; + if (msqid < 0 || (long) bufsz < 0) return -EINVAL; if (msgflg & MSG_COPY) { - copy = prepare_copy(buf, bufsz, msgflg, &msgtyp, ©_number); + copy = prepare_copy(buf, min_t(size_t, bufsz, ns->msg_ctlmax), + msgflg, &msgtyp, ©_number); if (IS_ERR(copy)) return PTR_ERR(copy); } mode = convert_mode(&msgtyp, msgflg); - ns = current->nsproxy->ipc_ns; msq = msg_lock_check(ns, msqid); if (IS_ERR(msq)) {