linux-ext4 - [Bug 198301] ext4 fails to create symlink if target length is greater than block size (but smaller than PATH

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 for Android: free password hash cracker in your pocket

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

Message-ID: <bug-198301-13602-lXUh7ZKLl7@https.bugzilla.kernel.org/>
Date:   Sun, 14 Jan 2018 00:16:34 +0000
From:   bugzilla-daemon@...zilla.kernel.org
To:     linux-ext4@...nel.org
Subject: [Bug 198301] ext4 fails to create symlink if target length is
 greater than block size (but smaller than PATH_MAX)

https://bugzilla.kernel.org/show_bug.cgi?id=198301

Eric Biggers (ebiggers3@...il.com) changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ebiggers3@...il.com

--- Comment #7 from Eric Biggers (ebiggers3@...il.com) ---
> The strange side effect of this bug is that one can not link to every file in
> a file system with a block size of e.g. 1k while PATH_MAX is 4k.

Note that you cannot necessarily link to every file in the filesystem even with
a 4k block size, since the absolute path to a file can be over PATH_MAX. 
PATH_MAX is a limit on the path string passed to syscalls, not a limit on the
directory structure.  By using cwd-relative paths, fd-relative paths, chroots,
or bind mounts, you can create a directory structure that is much deeper than
PATH_MAX.  None of the major Linux filesystems enforce a directory depth limit,
as far as I know -- and even if one did, it could still be mounted at a
mountpoint whose absolute path is already PATH_MAX, or close to it.

-- 
You are receiving this mail because:
You are watching the assignee of the bug.