kbuild: add support for squashing uid/gid in gen_initramfs_list.sh

Sometimes it is useful to squash all uid's/gid's to 0:0 regardless of
current owner.  For example, in build systems that get run as arbitrary
users (uClinux-dist).  This adds a special "squash" keyword so you can do
'-g squash -u squash' and have ownership squashed to root.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/scripts/gen_initramfs_list.sh b/scripts/gen_initramfs_list.sh
index 683eb12babbb3a46730cd39aadb03166a7cf2648..684fb9cdc055cc15d1ac3f39cdbd9fa47a245104 100644 (file)
--- a/scripts/gen_initramfs_list.sh
+++ b/scripts/gen_initramfs_list.sh
@@ -19,11 +19,11 @@ $0 [-o <file>] [-u <uid>] [-g <gid>] {-d | <cpio_source>} ...
        -o <file>      Create gzipped initramfs file named <file> using
                       gen_init_cpio and gzip
        -u <uid>       User ID to map to user ID 0 (root).
-                      <uid> is only meaningful if <cpio_source>
-                      is a directory.
+                      <uid> is only meaningful if <cpio_source> is a
+                      directory.  "squash" forces all files to uid 0.
        -g <gid>       Group ID to map to group ID 0 (root).
-                      <gid> is only meaningful if <cpio_source>
-                      is a directory.
+                      <gid> is only meaningful if <cpio_source> is a
+                      directory.  "squash" forces all files to gid 0.
        <cpio_source>  File list or directory for cpio archive.
                       If <cpio_source> is a .cpio file it will be used
                       as direct input to initramfs.
@@ -113,8 +113,8 @@ parse() {
        local gid="$4"
        local ftype=$(filetype "${location}")
        # remap uid/gid to 0 if necessary
-       [ "$uid" -eq "$root_uid" ] && uid=0
-       [ "$gid" -eq "$root_gid" ] && gid=0
+       [ "$root_uid" = "squash" ] && uid=0 || [ "$uid" -eq "$root_uid" ] && uid=0
+       [ "$root_gid" = "squash" ] && gid=0 || [ "$gid" -eq "$root_gid" ] && gid=0
        local str="${mode} ${uid} ${gid}"
 
        [ "${ftype}" == "invalid" ] && return 0