linux-kernel - Re: nfs regression 2.6.35+

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <s5hfwyelu28.wl%tiwai@suse.de>
Date:	Mon, 16 Aug 2010 12:40:15 +0200
From:	Takashi Iwai <tiwai@...e.de>
To:	Shaohua Li <shaohua.li@...el.com>
Cc:	Trond.Myklebust@...app.com, rjw@...k.pl,
	linux-kernel@...r.kernel.org, linux-nfs@...r.kernel.org
Subject: Re: nfs regression 2.6.35+

At Mon, 16 Aug 2010 12:09:12 +0200, Takashi Iwai wrote:
> At Mon, 16 Aug 2010 15:06:26 +0800,
> Shaohua Li wrote:
> > 
> > NFS client runs latest git. At client side, use vim to edit a file located at
> > NFS server. If I save the file, vim always reports 'E667: Fsync failed'. If I
> > revert f7fa16506bf9b6323e862a61e14c20555152bb3, vim works. No kernel errors
> > reported.
> 
> This hits me, too.  Reverting it cures the problem.
> (BTW, the correct commit id of the affecting patch is
>  af7fa16506bf9b6323e862a61e14c20555152bb3
>  "NFS: Fix up the fsync code")
> 
> Reproduced on 2.6.36-rc1.
> 
> Looking at strace output, 
> 
>   open("afo", O_WRONLY|O_CREAT|O_TRUNC, 0666) = 4
>   write(4, "#!/bin\n", 7)                 = 7
>   fsync(4)                                = 1
>   stat("afo", {st_mode=S_IFREG|0644, st_size=7, ...}) = 0
>   close(4)                                = 0
> 
> So, fsync() returns 1 wrongly.

How about a band-aid fix below?


Takashi


>From c75eab5ac47f5ce27a0d450423f8c46824f832f0 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@...e.de>
Date: Mon, 16 Aug 2010 12:25:19 +0200
Subject: [PATCH] NFS: fix fsync return code

With the commit af7fa16506bf9b6323e862a61e14c20555152bb3
    NFS: Fix up the fsync code
fsync returns a postive number for success incorrectly because now it
calls nfs_commit_inode() which returns the number of pages.

This patch makes fsync simply ignore a positive return value.

Signed-off-by: Takashi Iwai <tiwai@...e.de>
---
 fs/nfs/file.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 2d141a7..eb51bd6 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -323,7 +323,7 @@ nfs_file_fsync(struct file *file, int datasync)
 	have_error |= test_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags);
 	if (have_error)
 		ret = xchg(&ctx->error, 0);
-	if (!ret)
+	if (!ret && status < 0)
 		ret = status;
 	return ret;
 }
-- 
1.7.2.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/