Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964928AbbFJNos (ORCPT ); Wed, 10 Jun 2015 09:44:48 -0400 Received: from mail-lb0-f173.google.com ([209.85.217.173]:33198 "EHLO mail-lb0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933810AbbFJNoI (ORCPT ); Wed, 10 Jun 2015 09:44:08 -0400 MIME-Version: 1.0 In-Reply-To: References: Date: Wed, 10 Jun 2015 15:44:06 +0200 Message-ID: Subject: Re: [PATCH v2 01/10] kdbus: fix operator precedence issues in item macros From: David Herrmann To: Sergei Zviagintsev Cc: Greg Kroah-Hartman , Daniel Mack , David Herrmann , Djalal Harouni , linux-kernel Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2118 Lines: 57 Hi On Tue, Jun 9, 2015 at 10:59 PM, Sergei Zviagintsev wrote: > `_i' argument in KDBUS_ITEM_NEXT and KDBUS_ITEMS_END macros is not > enclosed into parentheses when the cast operator is applied, which > leads to improper type conversion if `_i' is supplied as a complex > expression, e.g. > > KDBUS_ITEM_NEXT(condition ? a : b) > > KDBUS_ITEMS_SIZE macro has similar issue, missing parentheses around > `_h' when using indirection operator. > > Use parentheses properly to guarantee right precedence. > > Signed-off-by: Sergei Zviagintsev > --- > ipc/kdbus/item.h | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) Reviewed-by: David Herrmann Thanks David > diff --git a/ipc/kdbus/item.h b/ipc/kdbus/item.h > index eeefd8beac3b..32909e2e7954 100644 > --- a/ipc/kdbus/item.h > +++ b/ipc/kdbus/item.h > @@ -21,8 +21,8 @@ > #include "util.h" > > /* generic access and iterators over a stream of items */ > -#define KDBUS_ITEM_NEXT(_i) (typeof(_i))(((u8 *)_i) + KDBUS_ALIGN8((_i)->size)) > -#define KDBUS_ITEMS_SIZE(_h, _is) ((_h)->size - offsetof(typeof(*_h), _is)) > +#define KDBUS_ITEM_NEXT(_i) (typeof(_i))((u8 *)(_i) + KDBUS_ALIGN8((_i)->size)) > +#define KDBUS_ITEMS_SIZE(_h, _is) ((_h)->size - offsetof(typeof(*(_h)), _is)) > #define KDBUS_ITEM_HEADER_SIZE offsetof(struct kdbus_item, data) > #define KDBUS_ITEM_SIZE(_s) KDBUS_ALIGN8(KDBUS_ITEM_HEADER_SIZE + (_s)) > #define KDBUS_ITEM_PAYLOAD_SIZE(_i) ((_i)->size - KDBUS_ITEM_HEADER_SIZE) > @@ -40,7 +40,7 @@ > (u8 *)(_i) >= (u8 *)(_is)) > > #define KDBUS_ITEMS_END(_i, _is, _s) \ > - ((u8 *)_i == ((u8 *)(_is) + KDBUS_ALIGN8(_s))) > + ((u8 *)(_i) == ((u8 *)(_is) + KDBUS_ALIGN8(_s))) > > /** > * struct kdbus_item_header - Describes the fix part of an item > -- > 1.8.3.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/