[PATCH] dracut: write initramfs to temp file then move into place

[PATCH] dracut: write initramfs to temp file then move into place

[lars-3XmpO8hA3EAAvxtiuMwx3w]

From: "Lars R. Damerow" <lars-3XmpO8hA3EAAvxtiuMwx3w@public.gmane.org>

We've been finding cases where multiple instances of dracut can be launched
simultaneously, resulting in a corrupted initramfs file. This patch makes
dracut write the initramfs to a new file, then move it into place atomically.
---
 dracut.sh | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/dracut.sh b/dracut.sh
index 31cf2a5..da96aaa 100755
--- a/dracut.sh
+++ b/dracut.sh
@@ -1103,10 +1103,11 @@ fi
 rm -f "$outfile"
 dinfo "*** Creating image file ***"
 if ! ( umask 077; cd "$initdir"; find . |cpio -R 0:0 -H newc -o --quiet| \
-    $compress > "$outfile"; ); then
-    dfatal "dracut: creation of $outfile failed"
+    $compress > "$outfile.$$"; ); then
+    dfatal "dracut: creation of $outfile.$$ failed"
     exit 1
 fi
+mv $outfile.$$ $outfile
 dinfo "*** Creating image file done ***"
 
 dinfo "Wrote $outfile:"
-- 
1.8.0

Re: [PATCH] dracut: write initramfs to temp file then move into place

[Harald Hoyer]

Am 21.02.2013 22:40, schrieb lars-3XmpO8hA3EAAvxtiuMwx3w@public.gmane.org:
> From: "Lars R. Damerow" <lars-3XmpO8hA3EAAvxtiuMwx3w@public.gmane.org>
> 
> We've been finding cases where multiple instances of dracut can be launched
> simultaneously, resulting in a corrupted initramfs file. This patch makes
> dracut write the initramfs to a new file, then move it into place atomically.
> ---
>  dracut.sh | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/dracut.sh b/dracut.sh
> index 31cf2a5..da96aaa 100755
> --- a/dracut.sh
> +++ b/dracut.sh
> @@ -1103,10 +1103,11 @@ fi
>  rm -f "$outfile"
>  dinfo "*** Creating image file ***"
>  if ! ( umask 077; cd "$initdir"; find . |cpio -R 0:0 -H newc -o --quiet| \
> -    $compress > "$outfile"; ); then
> -    dfatal "dracut: creation of $outfile failed"
> +    $compress > "$outfile.$$"; ); then
> +    dfatal "dracut: creation of $outfile.$$ failed"
>      exit 1
>  fi
> +mv $outfile.$$ $outfile
>  dinfo "*** Creating image file done ***"
>  
>  dinfo "Wrote $outfile:"
> 

Yes, right!
Thanks for the patch!