From 248b69d63068cabd7463c325d2ecc3db3239272e Mon Sep 17 00:00:00 2001

From: Daan De Meyer <daan.j.demeyer@gmail.com>

Date: Tue, 23 Jul 2024 13:14:05 +0200

Subject: [PATCH] tmpfiles: make --purge hard to (mis-)use

Follow-up for https://github.com/systemd/systemd/pull/33383.

---

 src/tmpfiles/tmpfiles.c           | 17 +++++++++++++++++

 test/units/TEST-22-TMPFILES.18.sh |  6 +++---

 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/src/tmpfiles/tmpfiles.c b/src/tmpfiles/tmpfiles.c

index 86bf16356d..539c18f5e0 100644

--- a/src/tmpfiles/tmpfiles.c

+++ b/src/tmpfiles/tmpfiles.c

@@ -4213,6 +4213,7 @@ static int parse_argv(int argc, char *argv[]) {

                 ARG_IMAGE_POLICY,

                 ARG_REPLACE,

                 ARG_DRY_RUN,

+                ARG_DESTROY_DATA,

                 ARG_NO_PAGER,

         };

@@ -4236,10 +4237,18 @@ static int parse_argv(int argc, char *argv[]) {

                 { "replace",        required_argument,   NULL, ARG_REPLACE        },

                 { "dry-run",        no_argument,         NULL, ARG_DRY_RUN        },

                 { "no-pager",       no_argument,         NULL, ARG_NO_PAGER       },

+

+                /* This is not documented on purpose.

+                 * If you think --purge should be allowed without jumping through hoops,

+                 * consider opening a bug report with the description of the use case.

+                 */

+                { "destroy-data",   no_argument,         NULL, ARG_DESTROY_DATA   },

+

                 {}

         };

         int c, r;

+        bool destroy_data = false;

         assert(argc >= 0);

         assert(argv);

@@ -4346,6 +4355,10 @@ static int parse_argv(int argc, char *argv[]) {

                         arg_dry_run = true;

                         break;

+                case ARG_DESTROY_DATA:

+                        destroy_data = true;

+                        break;

+

                 case ARG_NO_PAGER:

                         arg_pager_flags |= PAGER_DISABLE;

                         break;

@@ -4365,6 +4378,10 @@ static int parse_argv(int argc, char *argv[]) {

                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),

                                        "Refusing --purge without specification of a configuration file.");

+        if (FLAGS_SET(arg_operation, OPERATION_PURGE) && !arg_dry_run && !destroy_data)

+                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),

+                                       "Refusing --purge without --destroy-data.");

+

         if (arg_replace && arg_cat_flags != CAT_CONFIG_OFF)

                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),

                                        "Option --replace= is not supported with --cat-config/--tldr.");

diff --git a/test/units/TEST-22-TMPFILES.18.sh b/test/units/TEST-22-TMPFILES.18.sh

index c81f6bd0ef..1eb264a279 100755

--- a/test/units/TEST-22-TMPFILES.18.sh

+++ b/test/units/TEST-22-TMPFILES.18.sh

@@ -24,7 +24,7 @@ test -f /tmp/somedir/somefile

 grep -q baz /tmp/somedir/somefile

 grep -q qux /tmp/someotherfile

-systemd-tmpfiles --purge - <<<"$c"

+systemd-tmpfiles --purge --destroy-data - <<<"$c"

 test ! -f /tmp/somedir/somefile

 test ! -d /tmp/somedir/

 grep -q qux /tmp/someotherfile

@@ -34,12 +34,12 @@ test ! -f /tmp/somedir/somefile

 test ! -d /tmp/somedir/

 grep -q qux /tmp/someotherfile

-systemd-tmpfiles --create --purge - <<<"$c"

+systemd-tmpfiles --create --destroy-data --purge - <<<"$c"

 test -f /tmp/somedir/somefile

 grep -q baz /tmp/somedir/somefile

 grep -q qux /tmp/someotherfile

-systemd-tmpfiles --purge - <<<"$c"

+systemd-tmpfiles --purge --destroy-data - <<<"$c"

 test ! -f /tmp/somedir/somefile

 test ! -d /tmp/somedir/

 grep -q qux /tmp/someotherfile

-- 

2.47.0