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Date: Mon, 31 Mar 2025 12:12:52 -0600
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Subject: Re: symbolic link curiousity in 3.6.0
To: =?UTF-8?Q?P=C3=A1draig_Brady?= <P AT draigBrady DOT com>
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Autocrypt: addr=eggert AT cs DOT ucla DOT edu; keydata=
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On 3/31/25 11:27, Pádraig Brady wrote:
> The file could be deleted at any time.
> We're just suppressing errors in the edge case it's deleted

More generally, though, the file could be renamed and another put in its 
place, which means that an attacker could cause 'ls' to generate a line 
that does not correspond to any state of any file.

For this sort of attack an O_PATH solution is the only defense I can 
think of (for systems with O_PATH and /proc/self/fd; I don't know of 
solutions elsewhere.) And if we use O_PATH for this, we've solved the 
problem for the file-being-deleted case too.

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