diff options
Diffstat (limited to '')
| -rw-r--r-- | debian/patches/0002-pager-set-LESSSECURE-whenver-we-invoke-a-pager.patch | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/debian/patches/0002-pager-set-LESSSECURE-whenver-we-invoke-a-pager.patch b/debian/patches/0002-pager-set-LESSSECURE-whenver-we-invoke-a-pager.patch new file mode 100644 index 0000000..4b4ccc3 --- /dev/null +++ b/debian/patches/0002-pager-set-LESSSECURE-whenver-we-invoke-a-pager.patch @@ -0,0 +1,112 @@ +From 47bf4e7c6be2f73ecc8cfd8732920987df09e487 Mon Sep 17 00:00:00 2001 +From: Lennart Poettering <lennart@poettering.net> +Date: Mon, 31 Aug 2020 19:37:13 +0200 +Subject: pager: set $LESSSECURE whenver we invoke a pager + +Some extra safety when invoked via "sudo". With this we address a +genuine design flaw of sudo, and we shouldn't need to deal with this. +But it's still a good idea to disable this surface given how exotic it +is. + +Prompted by #5666 +--- + man/less-variables.xml | 9 +++++++++ + man/systemctl.xml | 1 + + man/systemd.xml | 1 + + src/shared/pager.c | 23 +++++++++++++++++++++-- + 4 files changed, 32 insertions(+), 2 deletions(-) + +diff --git a/man/less-variables.xml b/man/less-variables.xml +index 334eb19871..fed4178b01 100644 +--- a/man/less-variables.xml ++++ b/man/less-variables.xml +@@ -60,5 +60,14 @@ + </listitem> + </varlistentry> + ++ <varlistentry id='lesssecure'> ++ <term><varname>$SYSTEMD_LESSSECURE</varname></term> ++ ++ <listitem><para>Takes a boolean argument. Overrides the <varname>$LESSSECURE</varname> environment ++ variable when invoking the pager, which controls the "secure" mode of less (which disables commands ++ such as <literal>|</literal> which allow to easily shell out to external command lines). By default ++ less secure mode is enabled, with this setting it may be disabled.</para></listitem> ++ </varlistentry> ++ + </variablelist> + </refsect1> +diff --git a/man/systemctl.xml b/man/systemctl.xml +index 08aacd8f41..22b26d3607 100644 +--- a/man/systemctl.xml ++++ b/man/systemctl.xml +@@ -2039,6 +2039,7 @@ Jan 12 10:46:45 example.com bluetoothd[8900]: gatt-time-server: Input/output err + <xi:include href="less-variables.xml" xpointer="pager"/> + <xi:include href="less-variables.xml" xpointer="less"/> + <xi:include href="less-variables.xml" xpointer="lesscharset"/> ++ <xi:include href="less-variables.xml" xpointer="lesssecure"/> + </refsect1> + + <refsect1> +diff --git a/man/systemd.xml b/man/systemd.xml +index 1ff1f34dbe..d0d847c353 100644 +--- a/man/systemd.xml ++++ b/man/systemd.xml +@@ -875,6 +875,7 @@ + + <xi:include href="less-variables.xml" xpointer="colors" /> + <xi:include href="less-variables.xml" xpointer="urlify" /> ++ <xi:include href="less-variables.xml" xpointer="lesssecure"/> + + <varlistentry> + <term><varname>$LISTEN_PID</varname></term> +diff --git a/src/shared/pager.c b/src/shared/pager.c +index bf2597e65a..7a56271760 100644 +--- a/src/shared/pager.c ++++ b/src/shared/pager.c +@@ -11,6 +11,7 @@ + #include <unistd.h> + + #include "copy.h" ++#include "env-util.h" + #include "fd-util.h" + #include "fileio.h" + #include "io-util.h" +@@ -152,8 +153,7 @@ int pager_open(PagerFlags flags) { + _exit(EXIT_FAILURE); + } + +- /* Initialize a good charset for less. This is +- * particularly important if we output UTF-8 ++ /* Initialize a good charset for less. This is particularly important if we output UTF-8 + * characters. */ + less_charset = getenv("SYSTEMD_LESSCHARSET"); + if (!less_charset && is_locale_utf8()) +@@ -164,6 +164,25 @@ int pager_open(PagerFlags flags) { + _exit(EXIT_FAILURE); + } + ++ /* People might invoke us from sudo, don't needlessly allow less to be a way to shell out ++ * privileged stuff. */ ++ r = getenv_bool("SYSTEMD_LESSSECURE"); ++ if (r == 0) { /* Remove env var if off */ ++ if (unsetenv("LESSSECURE") < 0) { ++ log_error_errno(errno, "Failed to uset environment variable LESSSECURE: %m"); ++ _exit(EXIT_FAILURE); ++ } ++ } else { ++ /* Set env var otherwise */ ++ if (r < 0) ++ log_warning_errno(r, "Unable to parse $SYSTEMD_LESSSECURE, ignoring: %m"); ++ ++ if (setenv("LESSSECURE", "1", 1) < 0) { ++ log_error_errno(errno, "Failed to set environment variable LESSSECURE: %m"); ++ _exit(EXIT_FAILURE); ++ } ++ } ++ + if (pager_args) { + r = loop_write(exe_name_pipe[1], pager_args[0], strlen(pager_args[0]) + 1, false); + if (r < 0) { +-- +2.30.2 + |