Merge from trunk.

1 files changed, 27 insertions, 8 deletions

diff --git a/src/fileio.c b/src/fileio.c
index af11e927059..60ee35bb399 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -38,8 +38,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <selinux/context.h>
 #endif
 
-#include <ignore-value.h>
-
 #include "lisp.h"
 #include "intervals.h"
 #include "buffer.h"
@@ -1939,10 +1937,19 @@ on the system, we copy the SELinux context of FILE to NEWNAME.  */)
                     | (NILP (ok_if_already_exists) ? O_EXCL : 0),
                     S_IREAD | S_IWRITE);
 #else  /* not MSDOS */
-  ofd = emacs_open (SSDATA (encoded_newname),
-                    O_WRONLY | O_TRUNC | O_CREAT
-                    | (NILP (ok_if_already_exists) ? O_EXCL : 0),
-                    0666);
+  {
+    int new_mask = 0666;
+    if (input_file_statable_p)
+      {
+        if (!NILP (preserve_uid_gid))
+          new_mask = 0600;
+        new_mask &= st.st_mode;
+      }
+    ofd = emacs_open (SSDATA (encoded_newname),
+                      (O_WRONLY | O_TRUNC | O_CREAT
+                       | (NILP (ok_if_already_exists) ? O_EXCL : 0)),
+                      new_mask);
+  }
 #endif /* not MSDOS */
   if (ofd < 0)
     report_file_error ("Opening output file", Fcons (newname, Qnil));
@@ -1961,9 +1968,21 @@ on the system, we copy the SELinux context of FILE to NEWNAME.  */)
      owner and group.  */
   if (input_file_statable_p)
     {
+      int mode_mask = 07777;
       if (!NILP (preserve_uid_gid))
-        ignore_value (fchown (ofd, st.st_uid, st.st_gid));
-      if (fchmod (ofd, st.st_mode & 07777) != 0)
+        {
+          /* Attempt to change owner and group.  If that doesn't work
+             attempt to change just the group, as that is sometimes allowed.
+             Adjust the mode mask to eliminate setuid or setgid bits
+             that are inappropriate if the owner and group are wrong.  */
+          if (fchown (ofd, st.st_uid, st.st_gid) != 0)
+            {
+              mode_mask &= ~06000;
+              if (fchown (ofd, -1, st.st_gid) == 0)
+                mode_mask |= 02000;
+            }
+        }
+      if (fchmod (ofd, st.st_mode & mode_mask) != 0)
         report_file_error ("Doing chmod", Fcons (newname, Qnil));
     }
 #endif  /* not MSDOS */