Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759365Ab3ICFdq (ORCPT ); Tue, 3 Sep 2013 01:33:46 -0400 Received: from intranet.asianux.com ([58.214.24.6]:33767 "EHLO intranet.asianux.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753133Ab3ICFdp (ORCPT ); Tue, 3 Sep 2013 01:33:45 -0400 X-Spam-Score: -100.9 Message-ID: <52257478.7070305@asianux.com> Date: Tue, 03 Sep 2013 13:32:40 +0800 From: Chen Gang User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 To: Andrew Morton CC: Mel Gorman , kosaki.motohiro@jp.fujitsu.com, riel@redhat.com, hughd@google.com, xemul@parallels.com, rientjes@google.com, Wanpeng Li , Cyrill Gorcunov , linux-mm@kvack.org, "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] mm/shmem.c: check the return value of mpol_to_str() References: <5212E8DF.5020209@asianux.com> <20130820053036.GB18673@moon> <52130194.4030903@asianux.com> <20130820064730.GD18673@moon> <52131F48.1030002@asianux.com> <52132011.60501@asianux.com> <52132432.3050308@asianux.com> <20130820082516.GE18673@moon> <52142422.9050209@asianux.com> <52142464.8060903@asianux.com> <521424BE.8020309@asianux.com> <20130821150337.bad5f71869cec813e2ded90c@linux-foundation.org> <521560BB.30006@asianux.com> <5215639D.1080202@asianux.com> In-Reply-To: <5215639D.1080202@asianux.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2438 Lines: 82 Hello Maintainers: Please help check this patch, when you have time. If it need additional test, please let me know, I should try (better to provide some suggestions for test). Thanks. On 08/22/2013 09:04 AM, Chen Gang wrote: > mpol_to_str() may fail, and not fill the buffer (e.g. -EINVAL), so need > check about it, or buffer may not be zero based, and next seq_printf() > will cause issue. > > Also need let shmem_show_mpol() return value, since it may fail. > > Signed-off-by: Chen Gang > Reviewed-by: Cyrill Gorcunov > --- > mm/shmem.c | 16 ++++++++++------ > 1 files changed, 10 insertions(+), 6 deletions(-) > > diff --git a/mm/shmem.c b/mm/shmem.c > index f00c1c1..b4d44db 100644 > --- a/mm/shmem.c > +++ b/mm/shmem.c > @@ -883,16 +883,20 @@ redirty: > > #ifdef CONFIG_NUMA > #ifdef CONFIG_TMPFS > -static void shmem_show_mpol(struct seq_file *seq, struct mempolicy *mpol) > +static int shmem_show_mpol(struct seq_file *seq, struct mempolicy *mpol) > { > char buffer[64]; > + int ret; > > if (!mpol || mpol->mode == MPOL_DEFAULT) > - return; /* show nothing */ > + return 0; /* show nothing */ > > - mpol_to_str(buffer, sizeof(buffer), mpol); > + ret = mpol_to_str(buffer, sizeof(buffer), mpol); > + if (ret < 0) > + return ret; > > seq_printf(seq, ",mpol=%s", buffer); > + return 0; > } > > static struct mempolicy *shmem_get_sbmpol(struct shmem_sb_info *sbinfo) > @@ -951,8 +955,9 @@ static struct page *shmem_alloc_page(gfp_t gfp, > } > #else /* !CONFIG_NUMA */ > #ifdef CONFIG_TMPFS > -static inline void shmem_show_mpol(struct seq_file *seq, struct mempolicy *mpol) > +static inline int shmem_show_mpol(struct seq_file *seq, struct mempolicy *mpol) > { > + return 0; > } > #endif /* CONFIG_TMPFS */ > > @@ -2555,8 +2560,7 @@ static int shmem_show_options(struct seq_file *seq, struct dentry *root) > if (!gid_eq(sbinfo->gid, GLOBAL_ROOT_GID)) > seq_printf(seq, ",gid=%u", > from_kgid_munged(&init_user_ns, sbinfo->gid)); > - shmem_show_mpol(seq, sbinfo->mpol); > - return 0; > + return shmem_show_mpol(seq, sbinfo->mpol); > } > #endif /* CONFIG_TMPFS */ > > -- Chen Gang -- 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/