[PATCH] 95rootfs-block: fix missing root when label contains slash

[PATCH] 95rootfs-block: fix missing root when label contains slash

[Andrey Borzenkov]

It is not clearly documented, but apparently fsck
(or, probably, getmntent) is using backslash as
escape character.

Label containing slash is converted to \x2f but '\'
is eaten by fsck later. Escape '\' before writing
into fstab.

Signed-off-by: Andrey Borzenkov <arvidjaar-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

---
 modules.d/95rootfs-block/mount-root.sh |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/modules.d/95rootfs-block/mount-root.sh b/modules.d/95rootfs-block/mount-root.sh
index ff64209..493b54b 100755
--- a/modules.d/95rootfs-block/mount-root.sh
+++ b/modules.d/95rootfs-block/mount-root.sh
@@ -106,7 +106,9 @@ if [ -n "$root" -a -z "${root%%block:*}" ]; then
             done
     fi
 
-    echo ${root#block:} "$NEWROOT" "$rootfs" ${rflags},${rootopts} 1 1 > /etc/fstab
+    # backslashes are treated as escape character in fstab
+    esc_root=$(echo ${root#block:} | sed ',\\,\\\\,g')
+    echo "$esc_root" "$NEWROOT" "$rootfs" ${rflags},${rootopts} 1 1 > /etc/fstab
 
     if [ -z "$fastboot" -a "$READONLY" != "yes" ]; then
         info "Checking filesystems"
-- 
tg: (921f4b5..) upstream/rootdev (depends on: master)

[PATCH v2] 95rootfs-block: fix missing root when label contains slash

[Andrey Borzenkov]

It is not clearly documented, but apparently fsck
(or, probably, getmntent) is using backslash as
escape character.

Label containing slash is converted to \x2f but '\'
is eaten by fsck later. Escape '\' before writing
into fstab.

v2:
- fix sed expression
- use printf instead of echo because echo eats '\' as well

Signed-off-by: Andrey Borzenkov <arvidjaar-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

---
 modules.d/95rootfs-block/mount-root.sh |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/modules.d/95rootfs-block/mount-root.sh b/modules.d/95rootfs-block/mount-root.sh
index ff64209..9065bed 100755
--- a/modules.d/95rootfs-block/mount-root.sh
+++ b/modules.d/95rootfs-block/mount-root.sh
@@ -106,7 +106,9 @@ if [ -n "$root" -a -z "${root%%block:*}" ]; then
             done
     fi
 
-    echo ${root#block:} "$NEWROOT" "$rootfs" ${rflags},${rootopts} 1 1 > /etc/fstab
+    # backslashes are treated as escape character in fstab
+    esc_root=$(echo ${root#block:} | sed 's,\\,\\\\,g')
+    printf "%s $NEWROOT $rootfs ${rflags},${rootopts} 1 1\n" "$esc_root" > /etc/fstab
 
     if [ -z "$fastboot" -a "$READONLY" != "yes" ]; then
         info "Checking filesystems"
-- 
tg: (1c29003..) upstream/rootdev (depends on: master)

Re: [PATCH v2] 95rootfs-block: fix missing root when label contains slash

[Harald Hoyer]

On 11/06/2010 10:46 PM, Andrey Borzenkov wrote:
> It is not clearly documented, but apparently fsck
> (or, probably, getmntent) is using backslash as
> escape character.
>
> Label containing slash is converted to \x2f but '\'
> is eaten by fsck later. Escape '\' before writing
> into fstab.
>
> v2:
> - fix sed expression
> - use printf instead of echo because echo eats '\' as well
>
> Signed-off-by: Andrey Borzenkov<arvidjaar-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
>
> ---
>   modules.d/95rootfs-block/mount-root.sh |    4 +++-
>   1 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/modules.d/95rootfs-block/mount-root.sh b/modules.d/95rootfs-block/mount-root.sh
> index ff64209..9065bed 100755
> --- a/modules.d/95rootfs-block/mount-root.sh
> +++ b/modules.d/95rootfs-block/mount-root.sh
> @@ -106,7 +106,9 @@ if [ -n "$root" -a -z "${root%%block:*}" ]; then
>               done
>       fi
>
> -    echo ${root#block:} "$NEWROOT" "$rootfs" ${rflags},${rootopts} 1 1>  /etc/fstab
> +    # backslashes are treated as escape character in fstab
> +    esc_root=$(echo ${root#block:} | sed 's,\\,\\\\,g')
> +    printf "%s $NEWROOT $rootfs ${rflags},${rootopts} 1 1\n" "$esc_root">  /etc/fstab
>
>       if [ -z "$fastboot" -a "$READONLY" != "yes" ]; then
>           info "Checking filesystems"

maybe we should just turn \x2f back into / ??

Re: [PATCH v2] 95rootfs-block: fix missing root when label contains slash

[Harald Hoyer]

On 11/06/2010 10:46 PM, Andrey Borzenkov wrote:
> It is not clearly documented, but apparently fsck
> (or, probably, getmntent) is using backslash as
> escape character.
>
> Label containing slash is converted to \x2f but '\'
> is eaten by fsck later. Escape '\' before writing
> into fstab.
>
> v2:
> - fix sed expression
> - use printf instead of echo because echo eats '\' as well
>
> Signed-off-by: Andrey Borzenkov<arvidjaar-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
>
> ---
>   modules.d/95rootfs-block/mount-root.sh |    4 +++-
>   1 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/modules.d/95rootfs-block/mount-root.sh b/modules.d/95rootfs-block/mount-root.sh
> index ff64209..9065bed 100755
> --- a/modules.d/95rootfs-block/mount-root.sh
> +++ b/modules.d/95rootfs-block/mount-root.sh
> @@ -106,7 +106,9 @@ if [ -n "$root" -a -z "${root%%block:*}" ]; then
>               done
>       fi
>
> -    echo ${root#block:} "$NEWROOT" "$rootfs" ${rflags},${rootopts} 1 1>  /etc/fstab
> +    # backslashes are treated as escape character in fstab
> +    esc_root=$(echo ${root#block:} | sed 's,\\,\\\\,g')
> +    printf "%s $NEWROOT $rootfs ${rflags},${rootopts} 1 1\n" "$esc_root">  /etc/fstab
>
>       if [ -z "$fastboot" -a "$READONLY" != "yes" ]; then
>           info "Checking filesystems"

pushed