X-Git-Url: https://git.saurik.com/apt.git/blobdiff_plain/a4221092e50af0b74040f5b4ee800c78b05fd84e..9224ce3d4d1ea0428a70e75134998e08aa45b1e6:/apt-pkg/contrib/fileutl.cc

diff --git a/apt-pkg/contrib/fileutl.cc b/apt-pkg/contrib/fileutl.cc
index f6351b7b5..47033eadf 100644
--- a/apt-pkg/contrib/fileutl.cc
+++ b/apt-pkg/contrib/fileutl.cc
@@ -2066,9 +2066,11 @@ std::string GetTempDir()						/*{{{*/
       tmpdir = P_tmpdir;
 #endif
 
-   // check that tmpdir is set and exists
    struct stat st;
-   if (!tmpdir || strlen(tmpdir) == 0 || stat(tmpdir, &st) != 0)
+   if (!tmpdir || strlen(tmpdir) == 0 || // tmpdir is set
+	 stat(tmpdir, &st) != 0 || (st.st_mode & S_IFDIR) == 0 || // exists and is directory
+	 access(tmpdir, R_OK | W_OK | X_OK) != 0 // current user has rwx access to directory
+      )
       tmpdir = "/tmp";
 
    return string(tmpdir);
@@ -2168,12 +2170,6 @@ bool DropPrivileges()							/*{{{*/
    if(_config->FindB("Debug::NoDropPrivs", false) == true)
       return true;
 
-   // empty setting disables DropPrivilidges - this also ensures
-   // backward compatibility, see bug #764506
-   const std::string toUser = _config->Find("APT::Sandbox::User");
-   if (toUser.empty())
-      return true;
-
 #if __gnu_linux__
 #if defined(PR_SET_NO_NEW_PRIVS) && ( PR_SET_NO_NEW_PRIVS != 38 )
 #error "PR_SET_NO_NEW_PRIVS is defined, but with a different value than expected!"
@@ -2185,6 +2181,12 @@ bool DropPrivileges()							/*{{{*/
       _error->Warning("PR_SET_NO_NEW_PRIVS failed with %i", ret);
 #endif
 
+   // empty setting disables privilege dropping - this also ensures
+   // backward compatibility, see bug #764506
+   const std::string toUser = _config->Find("APT::Sandbox::User");
+   if (toUser.empty())
+      return true;
+
    // uid will be 0 in the end, but gid might be different anyway
    uid_t const old_uid = getuid();
    gid_t const old_gid = getgid();