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Message-ID: <4987030D.1070907@gmail.com>
Date: Mon, 02 Feb 2009 15:28:29 +0100
From: Roel Kluin <roel.kluin@gmail.com>
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To: hirofumi@mail.parknet.co.jp
CC: lkml <linux-kernel@vger.kernel.org>
Subject: msdos_format_name() bug?
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in msdos_format_name(const unsigned char *name, int len, ...)

name is the proposed name, len is its length.

        while (c != '.' && len--)
                c = *name++;
        if (c == '.') {
                while (walk - res < 8)
                        *walk++ = ' ';
                while (len > 0 && walk - res < MSDOS_NAME) {

Is the postfix decrement in the first loop correct, or should it be
prefix? (isn't that one character too many?)

If not, note that if the proposed name ends with a dot: e.g.
'myfile.' the first while loop iterates until the dot which ends
the loop, but because of the postfix decrement len already is 0,
so the third while loop won't start. Is that correct?

Roel