From: Lennart Poettering <lennart@poettering.net>
Date: Fri, 12 Nov 2021 10:16:02 +0000 (+0100)
Subject: namespace: make tmp dir handling code independent of umask too
X-Git-Tag: v250-rc1~290^2~1
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=30443439274cc223583c6c57f7d9041e440e346f;p=thirdparty%2Fsystemd.git

namespace: make tmp dir handling code independent of umask too

Let's make all code in namespace.c robust towards weird umask. This
doesn't matter too much given that the parent dirs we deal here almost
certainly exist anyway, but let's clean this up anyway and make it fully
clean.
---

diff --git a/src/core/namespace.c b/src/core/namespace.c
index 2239bbfb8aa..c01975b9de2 100644
--- a/src/core/namespace.c
+++ b/src/core/namespace.c
@@ -2508,7 +2508,8 @@ static int make_tmp_prefix(const char *prefix) {
         if (errno != ENOENT)
                 return -errno;
 
-        r = mkdir_parents(prefix, 0755);
+        RUN_WITH_UMASK(000)
+                r = mkdir_parents(prefix, 0755);
         if (r < 0)
                 return r;
 
@@ -2516,7 +2517,8 @@ static int make_tmp_prefix(const char *prefix) {
         if (r < 0)
                 return r;
 
-        if (mkdir(t, 0777) < 0)
+        if (mkdir(t, 0777) < 0) /* umask will corrupt this access mode, but that doesn't matter, we need to
+                                 * call chmod() anyway for the suid bit, below. */
                 return -errno;
 
         if (chmod(t, 01777) < 0) {
@@ -2574,10 +2576,9 @@ static int setup_one_tmp_dir(const char *id, const char *prefix, char **path, ch
                 if (!y)
                         return -ENOMEM;
 
-                RUN_WITH_UMASK(0000) {
+                RUN_WITH_UMASK(0000)
                         if (mkdir(y, 0777 | S_ISVTX) < 0)
                                     return -errno;
-                }
 
                 r = label_fix_container(y, prefix, 0);
                 if (r < 0)
@@ -2589,7 +2590,8 @@ static int setup_one_tmp_dir(const char *id, const char *prefix, char **path, ch
                 /* Trouble: we failed to create the directory. Instead of failing, let's simulate /tmp being
                  * read-only. This way the service will get the EROFS result as if it was writing to the real
                  * file system. */
-                r = mkdir_p(RUN_SYSTEMD_EMPTY, 0500);
+                RUN_WITH_UMASK(0000)
+                        r = mkdir_p(RUN_SYSTEMD_EMPTY, 0500);
                 if (r < 0)
                         return r;