linux-kernel - Re: utimes() with vfat is problematic

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Date:	Tue, 10 Jul 2007 12:18:17 +0200
From:	"Pawel Dziepak" <hryssta@...il.com>
To:	"Jan Engelhardt" <jengelh@...putergmbh.de>
Cc:	linux-fsdevel@...r.kernel.org,
	"Linux Kernel Mailing List" <linux-kernel@...r.kernel.org>,
	hirofumi@...l.parknet.co.jp
Subject: Re: utimes() with vfat is problematic

2007/7/10, Jan Engelhardt <jengelh@...putergmbh.de>:
> I am not sure how this could be dealt with besides passing -o quiet to
> mount.vfat. Any ideas?

The problem is in the function utimes. I have mounted vfat partition
as a root, then changed permissions to 777 for all files. However, I
wasn't be able to touch any file (changing date to the  past) as a
normal user. utimes() should check write permission instead of uid/
I didn't read 'touch' source code and it is probably caused by it's
procedures that I was able to change modification date to the current
date.
Single UNIX Specification says crealy that to do utimes on a file user
have to had write permissions or be a file owner.

Pawel
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