gen_init_cpio: remove leading `/' from file names

When we extracted the generated cpio archive using "cpio -id" command,
it complained,

cpio: Removing leading `/' from member names
var/run
cpio: Removing leading `/' from member names
var/lib
cpio: Removing leading `/' from member names
var/lib/misc

It is worse with the latest "cpio" or "pax", which tries to overwrite
the host file system with the leading '/'.

So the leading '/' of file names should be removed. This is consistent
with the initramfs come with major distributions such as Fedora or
Debian, etc.

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Acked-by: Mike Frysinger<vapier@gentoo.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>

1 files changed, 8 insertions, 0 deletions

diff --git a/usr/gen_init_cpio.c b/usr/gen_init_cpio.c
index b2b3c2d1cf8b..59df70d9d1dc 100644
--- a/usr/gen_init_cpio.c
+++ b/usr/gen_init_cpio.c
@@ -104,6 +104,8 @@ static int cpio_mkslink(const char *name, const char *target,
         char s[256];
         time_t mtime = time(NULL);
 
+        if (name[0] == '/')
+                name++;
         sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
                "%08X%08X%08X%08X%08X%08X%08X",
                 "070701",               /* magic */
@@ -152,6 +154,8 @@ static int cpio_mkgeneric(const char *name, unsigned int mode,
         char s[256];
         time_t mtime = time(NULL);
 
+        if (name[0] == '/')
+                name++;
         sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
                "%08X%08X%08X%08X%08X%08X%08X",
                 "070701",               /* magic */
@@ -245,6 +249,8 @@ static int cpio_mknod(const char *name, unsigned int mode,
         else
                 mode |= S_IFCHR;
 
+        if (name[0] == '/')
+                name++;
         sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
                "%08X%08X%08X%08X%08X%08X%08X",
                 "070701",               /* magic */
@@ -332,6 +338,8 @@ static int cpio_mkfile(const char *name, const char *location,
                 /* data goes on last link */
                 if (i == nlinks) size = buf.st_size;
 
+                if (name[0] == '/')
+                        name++;
                 namesize = strlen(name) + 1;
                 sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
                        "%08lX%08X%08X%08X%08X%08X%08X",