The inability to run strace or gdb is the kind of
developer-unfriendliness that we're used to from OS X, let's not do it
on NixOS.
This restriction can be re-enabled by setting
boot.kernel.sysctl."kernel.yama.ptrace_scope" = 1;
It might be nice to have a NixOS module for enabling hardened defaults.
Xref #14392.
Thanks @abbradar.
This is based on a prototype Nicolas B. Pierron worked on during a
discussion we had at FOSDEM.
A new version with a workaround for problems of the reverted original.
Discussion: https://github.com/NixOS/nixpkgs/commit/3f2566689
If a package's meta has `knownVulnerabilities`, like so:
stdenv.mkDerivation {
name = "foobar-1.2.3";
...
meta.knownVulnerabilities = [
"CVE-0000-00000: remote code execution"
"CVE-0000-00001: local privilege escalation"
];
}
and a user attempts to install the package, they will be greeted with
a warning indicating that maybe they don't want to install it:
error: Package ‘foobar-1.2.3’ in ‘...default.nix:20’ is marked as insecure, refusing to evaluate.
Known issues:
- CVE-0000-00000: remote code execution
- CVE-0000-00001: local privilege escalation
You can install it anyway by whitelisting this package, using the
following methods:
a) for `nixos-rebuild` you can add ‘foobar-1.2.3’ to
`nixpkgs.config.permittedInsecurePackages` in the configuration.nix,
like so:
{
nixpkgs.config.permittedInsecurePackages = [
"foobar-1.2.3"
];
}
b) For `nix-env`, `nix-build`, `nix-shell` or any other Nix command you can add
‘foobar-1.2.3’ to `permittedInsecurePackages` in
~/.config/nixpkgs/config.nix, like so:
{
permittedInsecurePackages = [
"foobar-1.2.3"
];
}
Adding either of these configurations will permit this specific
version to be installed. A third option also exists:
NIXPKGS_ALLOW_INSECURE=1 nix-build ...
though I specifically avoided having a global file-based toggle to
disable this check. This way, users don't disable it once in order to
get a single package, and then don't realize future packages are
insecure.
From Postfix documentation:
With this setting, the Postfix SMTP server will not reject mail with "User
unknown in local recipient table". Don't do this on systems that receive mail
directly from the Internet. With today's worms and viruses, Postfix will become
a backscatter source: it accepts mail for non-existent recipients and then
tries to return that mail as "undeliverable" to the often forged sender
address.
