mirror of
https://github.com/privatevoid-net/nix-super.git
synced 2024-11-25 23:36:16 +02:00
31 lines
1.4 KiB
XML
31 lines
1.4 KiB
XML
<section xmlns="http://docbook.org/ns/docbook"
|
||
xmlns:xlink="http://www.w3.org/1999/xlink"
|
||
xmlns:xi="http://www.w3.org/2001/XInclude"
|
||
version="5.0"
|
||
xml:id="ssec-relnotes-1.11.10">
|
||
|
||
<title>Release 1.11.10 (2017-06-12)</title>
|
||
|
||
<para>This release fixes a security bug in Nix’s “build user” build
|
||
isolation mechanism. Previously, Nix builders had the ability to
|
||
create setuid binaries owned by a <literal>nixbld</literal>
|
||
user. Such a binary could then be used by an attacker to assume a
|
||
<literal>nixbld</literal> identity and interfere with subsequent
|
||
builds running under the same UID.</para>
|
||
|
||
<para>To prevent this issue, Nix now disallows builders to create
|
||
setuid and setgid binaries. On Linux, this is done using a seccomp BPF
|
||
filter. Note that this imposes a small performance penalty (e.g. 1%
|
||
when building GNU Hello). Using seccomp, we now also prevent the
|
||
creation of extended attributes and POSIX ACLs since these cannot be
|
||
represented in the NAR format and (in the case of POSIX ACLs) allow
|
||
bypassing regular Nix store permissions. On macOS, the restriction is
|
||
implemented using the existing sandbox mechanism, which now uses a
|
||
minimal “allow all except the creation of setuid/setgid binaries”
|
||
profile when regular sandboxing is disabled. On other platforms, the
|
||
“build user” mechanism is now disabled.</para>
|
||
|
||
<para>Thanks go to Linus Heckemann for discovering and reporting this
|
||
bug.</para>
|
||
|
||
</section>
|