[systemd-devel] [RFC][PATCH] Escape unit name from udev

[MUNEDA Takahiro]

This patch escapes a unit name which was derived from udev.

Please imagine following udev rule.

  ACTION=="online|offline", TAG+="systemd", ENV{SYSTEMD_WANTS}="muneda@%p.service"
  ACTION=="online|offline", TAG+="systemd", ENV{SYSTEMD_WANTS}="muneda@%r.service"
  ACTION=="online|offline", TAG+="systemd", ENV{SYSTEMD_WANTS}="muneda@%S.service"

When unit name is derived from udev via
udev_device_get_property_value(), the name may contains '/' if
ENV{SYSTEMD_WANTS} has the udev options $devpath(%p), $root(%r), or
$sys(%S).  However, '/' is a invalid char for unit name so processing
of this rule fails as Invalid argument with following message.

Apr 22 13:21:37 localhost systemd[1]: Failed to load device unit: Invalid argument
Apr 22 13:21:37 localhost systemd[1]: Failed to process udev device event: Invalid argument

This patch escapes those invalid chars in a unit name.
Tested with 202, and confirmed to apply cleanly on top of commit 195f8e36.

Thanks,
Takahiro
---
 src/core/device.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/core/device.c b/src/core/device.c
index 734d3f3..7b28aba 100644
--- a/src/core/device.c
+++ b/src/core/device.c
@@ -281,16 +281,22 @@ static int device_update_unit(Manager *m, struct udev_device *dev, const char *p
                         size_t l;
 
                         FOREACH_WORD_QUOTED(w, l, wants, state) {
-                                char *e;
+                                char *e, *n;
 
                                 e = strndup(w, l);
                                 if (!e) {
                                         r = -ENOMEM;
                                         goto fail;
                                 }
-
-                                r = unit_add_dependency_by_name(u, UNIT_WANTS, e, NULL, true);
+                                n = unit_name_mangle(e);
+                                if (!n) {
+                                        r = -ENOMEM;
+                                        goto fail;
+                                }
                                 free(e);
+
+                                r = unit_add_dependency_by_name(u, UNIT_WANTS, n, NULL, true);
+                                free(n);
                                 if (r < 0)
                                         goto fail;
                         }
-- 
1.8.2