linux-kernel - is VM_GROWSDOWN still useful

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:	Sat, 21 Aug 2010 17:58:57 +0200
From:	castet.matthieu@...e.fr
To:	linux-kernel@...r.kernel.org
Subject: is VM_GROWSDOWN still useful

Hi,

I am wondering if the flags GROWSDOWN/GROWSUP is still useful on linux today. It
is only used for the main thread stack.
Stack allocated by pthread doesn't use anymore GROWSDOWN because you can't
guaranty that a user mapping (via mmap) will collide with it.

Why not doing the same for the main thread : allocate a stack of the rlimit size
?

Linux memory allocation use over-commit, and physical memory will only be
allocated when the stack is really used.

Or are they real usage of GROWSDOWN ?

Matthieu
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/