[PATCH] Fix "can't shift that many" crash with empty /proc/cmdline

[PATCH] Fix "can't shift that many" crash with empty /proc/cmdline

[Will Woods]

If /proc/cmdline is empty (like if root=... is set in /etc/cmdline),
modules.d/99base/init will crash with a message saying "can't shift that
many" right before switch_root. The problem is in the block of code that
tries to look for init args. It does something like:

read CMDLINE </proc/cpuinfo
    [...]
    set $CMDLINE
    shift

If CMDLINE="" then "set $CMDLINE" will dump all the variables to stdout.
(That should be "set -- $CMDLINE" instead.) Since there's no $1, the
"shift" causes an error, and dracut crashes.

The 'shift' was copy-and-pasted from the previous block. It doesn't
belong here; remove it.

Signed-off-by: Will Woods <wwoods-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 modules.d/99base/init |    7 +++----
 1 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/modules.d/99base/init b/modules.d/99base/init
index e2c34c7..87778ac 100755
--- a/modules.d/99base/init
+++ b/modules.d/99base/init
@@ -361,8 +361,8 @@ if getarg init= >/dev/null ; then
     ignoreargs="console BOOT_IMAGE"
     # only pass arguments after init= to the init
     CLINE=${CLINE#*init=}
-        set $CLINE
-        shift
+        set -- $CLINE
+        shift # clear out the rest of the "init=" arg
         for x in "$@"; do
             for s in $ignoreargs; do
                 [ "${x%%=*}" = $s ] && continue 2
@@ -372,8 +372,7 @@ if getarg init= >/dev/null ; then
         unset CLINE
 else
     set +x # Turn off debugging for this section
-    set $CLINE
-    shift
+    set -- $CLINE
     for x in "$@"; do
         case "$x" in
             [0-9]|s|S|single|emergency|auto ) \
-- 
1.7.5.1

Re: [PATCH] Fix "can't shift that many" crash with empty /proc/cmdline

[Harald Hoyer]

Am 17.05.2011 01:17, schrieb Will Woods:
> If /proc/cmdline is empty (like if root=... is set in /etc/cmdline),
> modules.d/99base/init will crash with a message saying "can't shift that
> many" right before switch_root. The problem is in the block of code that
> tries to look for init args. It does something like:
> 
> read CMDLINE </proc/cpuinfo
>     [...]
>     set $CMDLINE
>     shift
> 
> If CMDLINE="" then "set $CMDLINE" will dump all the variables to stdout.
> (That should be "set -- $CMDLINE" instead.) Since there's no $1, the
> "shift" causes an error, and dracut crashes.
> 
> The 'shift' was copy-and-pasted from the previous block. It doesn't
> belong here; remove it.
> 
> Signed-off-by: Will Woods <wwoods-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> ---
>  modules.d/99base/init |    7 +++----
>  1 files changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/modules.d/99base/init b/modules.d/99base/init
> index e2c34c7..87778ac 100755
> --- a/modules.d/99base/init
> +++ b/modules.d/99base/init
> @@ -361,8 +361,8 @@ if getarg init= >/dev/null ; then
>      ignoreargs="console BOOT_IMAGE"
>      # only pass arguments after init= to the init
>      CLINE=${CLINE#*init=}
> -        set $CLINE
> -        shift
> +        set -- $CLINE
> +        shift # clear out the rest of the "init=" arg
>          for x in "$@"; do
>              for s in $ignoreargs; do
>                  [ "${x%%=*}" = $s ] && continue 2
> @@ -372,8 +372,7 @@ if getarg init= >/dev/null ; then
>          unset CLINE
>  else
>      set +x # Turn off debugging for this section
> -    set $CLINE
> -    shift
> +    set -- $CLINE
>      for x in "$@"; do
>          case "$x" in
>              [0-9]|s|S|single|emergency|auto ) \


Thanks! Pushed