From bac7488e06e379628653fb2f3ece0a30414ff84e Mon Sep 17 00:00:00 2001

From: Lennart Poettering <lennart@poettering.net>

Date: Mon, 22 Jan 2018 21:03:53 +0100

Subject: [PATCH] tmpfiles: change ownership of symlinks too

Ownership is supported for symlinks, too, only file modes are not.

Support that too.

Fixes: #7509

(cherry picked from commit 51207ca134716a0dee5fd763a6c39204be849eb1)

Resolves: #1620110

---

 src/shared/macro.h      |  7 +++++++

 src/tmpfiles/tmpfiles.c | 41 +++++++++++++++++++++--------------------

 2 files changed, 28 insertions(+), 20 deletions(-)

diff --git a/src/shared/macro.h b/src/shared/macro.h

index 7a57f4e5b1..26df270d51 100644

--- a/src/shared/macro.h

+++ b/src/shared/macro.h

@@ -125,6 +125,13 @@ static inline unsigned long ALIGN_POWER2(unsigned long u) {

 #define ELEMENTSOF(x) (sizeof(x)/sizeof((x)[0]))

+/*

+ * STRLEN - return the length of a string literal, minus the trailing NUL byte.

+ *          Contrary to strlen(), this is a constant expression.

+ * @x: a string literal.

+ */

+#define STRLEN(x) (sizeof(""x"") - 1)

+

 /*

  * container_of - cast a member of a structure out to the containing structure

  * @ptr: the pointer to the member.

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

index 0b17b5908e..663f6c8b2d 100644

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

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

@@ -591,6 +591,7 @@ finish:

 }

 static int path_set_perms(Item *i, const char *path) {

+        char fn[STRLEN("/proc/self/fd/") + DECIMAL_STR_MAX(int)];

         _cleanup_close_ int fd = -1;

         struct stat st;

@@ -624,14 +625,12 @@ static int path_set_perms(Item *i, const char *path) {

         if (i->type == EMPTY_DIRECTORY && !S_ISDIR(st.st_mode))

                 return log_error_errno(EEXIST, "'%s' already exists and is not a directory. ", path);

-        if (S_ISLNK(st.st_mode))

-                log_debug("Skipping mode an owner fix for symlink %s.", path);

-        else {

-                char fn[strlen("/proc/self/fd/") + DECIMAL_STR_MAX(int)];

-                xsprintf(fn, "/proc/self/fd/%i", fd);

+        xsprintf(fn, "/proc/self/fd/%i", fd);

-                /* not using i->path directly because it may be a glob */

-                if (i->mode_set) {

+        if (i->mode_set) {

+                if (S_ISLNK(st.st_mode))

+                        log_debug("Skipping mode fix for symlink %s.", path);

+                else {

                         mode_t m = i->mode;

                         if (i->mask_perms) {

@@ -646,25 +645,27 @@ static int path_set_perms(Item *i, const char *path) {

                         }

                         if (m == (st.st_mode & 07777))

-                                log_debug("\"%s\" has right mode %o", path, st.st_mode);

+                                log_debug("\"%s\" has correct mode %o already.", path, st.st_mode);

                         else {

-                                log_debug("chmod \"%s\" to mode %o", path, m);

+                                log_debug("Changing \"%s\" to mode %o.", path, m);

+

                                 if (chmod(fn, m) < 0)

                                         return log_error_errno(errno, "chmod(%s) failed: %m", path);

                         }

                 }

+        }

-                if ((i->uid != st.st_uid || i->gid != st.st_gid) &&

-                    (i->uid_set || i->gid_set)) {

-                        log_debug("chown \"%s\" to "UID_FMT"."GID_FMT,

-                                  path,

-                                  i->uid_set ? i->uid : UID_INVALID,

-                                  i->gid_set ? i->gid : GID_INVALID);

-                        if (chown(fn,

-                                  i->uid_set ? i->uid : UID_INVALID,

-                                  i->gid_set ? i->gid : GID_INVALID) < 0)

-                        return log_error_errno(errno, "chown(%s) failed: %m", path);

-                }

+        if ((i->uid != st.st_uid || i->gid != st.st_gid) &&

+            (i->uid_set || i->gid_set)) {

+                log_debug("Changing \"%s\" to owner "UID_FMT":"GID_FMT,

+                          path,

+                          i->uid_set ? i->uid : UID_INVALID,

+                          i->gid_set ? i->gid : GID_INVALID);

+

+                if (chown(fn,

+                          i->uid_set ? i->uid : UID_INVALID,

+                          i->gid_set ? i->gid : GID_INVALID) < 0)

+                        return log_error_errno(errno, "chown() of %s via %s failed: %m", path, fn);

         }

         fd = safe_close(fd);