diff --git a/man/less-variables.xml b/man/less-variables.xml index 08e513c99f..c52511ca8e 100644 --- a/man/less-variables.xml +++ b/man/less-variables.xml @@ -64,6 +64,15 @@ the invoking terminal is determined to be UTF-8 compatible). + + $SYSTEMD_LESSSECURE + + Takes a boolean argument. Overrides the $LESSSECURE environment + variable when invoking the pager, which controls the "secure" mode of less (which disables commands + such as | which allow to easily shell out to external command lines). By default + less secure mode is enabled, with this setting it may be disabled. + + $SYSTEMD_COLORS diff --git a/man/systemctl.xml b/man/systemctl.xml index 1c55028837..a3f0c3041a 100644 --- a/man/systemctl.xml +++ b/man/systemctl.xml @@ -2240,6 +2240,7 @@ Jan 12 10:46:45 example.com bluetoothd[8900]: gatt-time-server: Input/output err + diff --git a/man/systemd.xml b/man/systemd.xml index a9040545c2..c92cfef776 100644 --- a/man/systemd.xml +++ b/man/systemd.xml @@ -692,6 +692,7 @@ + diff --git a/src/shared/pager.c b/src/shared/pager.c index e03be6d23b..9c21881241 100644 --- a/src/shared/pager.c +++ b/src/shared/pager.c @@ -9,6 +9,7 @@ #include #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) {