From c7d4f7a5a6cef5a46f905141e2ac27da3c96d2b7 Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>

Date: Mon, 23 Feb 2015 23:19:54 -0500

Subject: [PATCH] tmpfiles: avoid creating duplicate acl entries

https://bugs.freedesktop.org/show_bug.cgi?id=89202

https://bugs.debian.org/778656

Status quo ante can be restored with:

  getfacl -p /var/log/journal/`cat /etc/machine-id`|grep -v '^#'|sort -u|sudo setfacl --set-file=- /var/log/journal/`cat /etc/machine-id`

(cherry picked from commit 1c73f3bc29111a00738569c9d40a989b161a0624)

---

 src/shared/acl-util.c | 79 +++++++++++++++++++++++++++++++++++++++++--

 src/shared/acl-util.h |  4 +++

 2 files changed, 81 insertions(+), 2 deletions(-)

diff --git a/src/shared/acl-util.c b/src/shared/acl-util.c

index a4ff1ab87..cbe09d7ab 100644

--- a/src/shared/acl-util.c

+++ b/src/shared/acl-util.c

@@ -282,6 +282,77 @@ int parse_acl(char *text, acl_t *acl_access, acl_t *acl_default, bool want_mask)

         return 0;

 }

+static int acl_entry_equal(acl_entry_t a, acl_entry_t b) {

+        acl_tag_t tag_a, tag_b;

+

+        if (acl_get_tag_type(a, &tag_a) < 0)

+                return -errno;

+

+        if (acl_get_tag_type(b, &tag_b) < 0)

+                return -errno;

+

+        if (tag_a != tag_b)

+                return false;

+

+        switch (tag_a) {

+        case ACL_USER_OBJ:

+        case ACL_GROUP_OBJ:

+        case ACL_MASK:

+        case ACL_OTHER:

+                /* can have only one of those */

+                return true;

+        case ACL_USER: {

+                _cleanup_(acl_free_uid_tpp) uid_t *uid_a, *uid_b;

+

+                uid_a = acl_get_qualifier(a);

+                if (!uid_a)

+                        return -errno;

+

+                uid_b = acl_get_qualifier(b);

+                if (!uid_b)

+                        return -errno;

+

+                return *uid_a == *uid_b;

+        }

+        case ACL_GROUP: {

+                _cleanup_(acl_free_gid_tpp) gid_t *gid_a, *gid_b;

+

+                gid_a = acl_get_qualifier(a);

+                if (!gid_a)

+                        return -errno;

+

+                gid_b = acl_get_qualifier(b);

+                if (!gid_b)

+                        return -errno;

+

+                return *gid_a == *gid_b;

+        }

+        default:

+                assert_not_reached("Unknown acl tag type");

+        }

+}

+

+static int find_acl_entry(acl_t acl, acl_entry_t entry, acl_entry_t *out) {

+        acl_entry_t i;

+        int r;

+

+        for (r = acl_get_entry(acl, ACL_FIRST_ENTRY, &i);

+             r > 0;

+             r = acl_get_entry(acl, ACL_NEXT_ENTRY, &i)) {

+

+                r = acl_entry_equal(i, entry);

+                if (r < 0)

+                        return r;

+                if (r > 0) {

+                        *out = i;

+                        return 1;

+                }

+        }

+        if (r < 0)

+                return -errno;

+        return 0;

+}

+

 int acls_for_file(const char *path, acl_type_t type, acl_t new, acl_t *acl) {

         _cleanup_(acl_freep) acl_t old;

         acl_entry_t i;

@@ -297,8 +368,12 @@ int acls_for_file(const char *path, acl_type_t type, acl_t new, acl_t *acl) {

                 acl_entry_t j;

-                if (acl_create_entry(&old, &j) < 0)

-                        return -errno;

+                r = find_acl_entry(old, i, &j);

+                if (r < 0)

+                        return r;

+                if (r == 0)

+                        if (acl_create_entry(&old, &j) < 0)

+                                return -errno;

                 if (acl_copy_entry(j, i) < 0)

                         return -errno;

diff --git a/src/shared/acl-util.h b/src/shared/acl-util.h

index 90e88ffa2..fdb90063f 100644

--- a/src/shared/acl-util.h

+++ b/src/shared/acl-util.h

@@ -41,5 +41,9 @@ int acls_for_file(const char *path, acl_type_t type, acl_t new, acl_t *acl);

 DEFINE_TRIVIAL_CLEANUP_FUNC(acl_t, acl_free);

 #define acl_free_charp acl_free

 DEFINE_TRIVIAL_CLEANUP_FUNC(char*, acl_free_charp);

+#define acl_free_uid_tp acl_free

+DEFINE_TRIVIAL_CLEANUP_FUNC(uid_t*, acl_free_uid_tp);

+#define acl_free_gid_tp acl_free

+DEFINE_TRIVIAL_CLEANUP_FUNC(gid_t*, acl_free_gid_tp);

 #endif