Tighten pledge in List and Append mode:

Drop "wpath cpath fattr dpath" in read-only:
-  cpio -i -t < test.tar
-  pax < test.tar
-  tar -t -f test.tar

Drop "cpath fattr dpath" in read-write:
-  echo foo | cpio -o -A -H ustar -O test.tar
-  tar -r -f test.tar foo
-  pax -w -a -f test.tar foo

Other modes remain unchanged and thus can create or modify files.

Feedback OK millert

diff --git a/bin/pax/ar_io.c b/bin/pax/ar_io.c
index ddbd36e..ab0ea92 100644 (file)
--- a/bin/pax/ar_io.c
+++ b/bin/pax/ar_io.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: ar_io.c,v 1.63 2019/06/28 13:34:59 deraadt Exp $      */
+/*     $OpenBSD: ar_io.c,v 1.64 2023/11/09 18:54:15 kn Exp $   */
 /*     $NetBSD: ar_io.c,v 1.5 1996/03/26 23:54:13 mrg Exp $    */
 
 /*-
@@ -1261,9 +1261,16 @@ ar_start_gzip(int fd, const char *path, int wr)
                close(fds[1]);
 
                if (pmode == 0 || (act != EXTRACT && act != COPY)) {
-                   if (pledge("stdio rpath wpath cpath fattr dpath getpw proc tape",
-                       NULL) == -1)
-                               err(1, "pledge");
+                       if (act == LIST) {
+                               if (pledge("stdio rpath getpw proc tape",
+                                  NULL) == -1)
+                                       err(1, "pledge");
+                       /* can not gzip while appending */
+                       } else {
+                               if (pledge("stdio rpath wpath cpath fattr dpath getpw proc tape",
+                                  NULL) == -1)
+                                       err(1, "pledge");
+                       }
                }
        } else {
                if (wr) {

diff --git a/bin/pax/pax.c b/bin/pax/pax.c
index f86ba6d..1bdb616 100644 (file)
--- a/bin/pax/pax.c
+++ b/bin/pax/pax.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: pax.c,v 1.55 2023/10/15 09:49:57 kn Exp $     */
+/*     $OpenBSD: pax.c,v 1.56 2023/11/09 18:54:15 kn Exp $     */
 /*     $NetBSD: pax.c,v 1.5 1996/03/26 23:54:20 mrg Exp $      */
 
 /*-
@@ -273,13 +273,32 @@ main(int argc, char **argv)
        if (pmode == 0 || (act != EXTRACT && act != COPY)) {
                /* Copy mode, or no gzip -- don't need to fork/exec. */
                if (gzip_program == NULL || act == COPY) {
-                       if (pledge("stdio rpath wpath cpath fattr dpath getpw tape",
-                           NULL) == -1)
-                               err(1, "pledge");
+                       /* List mode -- don't need to write/create/modify files. */
+                       if (act == LIST) {
+                               if (pledge("stdio rpath getpw tape",
+                                   NULL) == -1)
+                                       err(1, "pledge");
+                       /* Append mode -- don't need to create/modify files. */
+                       } else if (act == APPND) {
+                               if (pledge("stdio rpath wpath getpw tape",
+                                   NULL) == -1)
+                                       err(1, "pledge");
+                       } else {
+                               if (pledge("stdio rpath wpath cpath fattr dpath getpw tape",
+                                   NULL) == -1)
+                                       err(1, "pledge");
+                       }
                } else {
-                       if (pledge("stdio rpath wpath cpath fattr dpath getpw proc exec tape",
-                           NULL) == -1)
-                               err(1, "pledge");
+                       if (act == LIST) {
+                               if (pledge("stdio rpath getpw proc exec tape",
+                                   NULL) == -1)
+                                       err(1, "pledge");
+                       /* can not gzip while appending */
+                       } else {
+                               if (pledge("stdio rpath wpath cpath fattr dpath getpw proc exec tape",
+                                   NULL) == -1)
+                                       err(1, "pledge");
+                       }
                }
        }