From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Tue, 17 Mar 2009 20:00:02 +0100
From: Jan Kiszka <jan.kiszka@domain.hid>
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Subject: Re: [Xenomai-core] [PATCH] posix: Fix error checks when copying
 user strings
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Cc: xenomai-core <xenomai@xenomai.org>

Gilles Chanteperdrix wrote:
> Jan Kiszka wrote:
>> Gilles Chanteperdrix wrote:
>>> Jan Kiszka wrote:
>>>> Obviously a conversion error while switching to __xn_safe*.
>>>>
>>>> Signed-off-by: Jan Kiszka <jan.kiszka@domain.hid>
>>> Well, I have just checked the kernel code, and 0 as a return value of
>>> strncpy_from_user is treated as a value in most places, even if not -EFAULT.
>>>
>> Better check our code: :) __xn_safe_strncpy_from_user works differently.
> 
> Then I would tend to consider that xn_safe_strncpy is broken.

No, because it not a derivate of strncpy_from_user, but an internal
service optimized for the most common use cases (where you don't care
about the precise return value).

Jan

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