diff options
| author |   Kees Cook <keescook@chromium.org> | 2015-01-26 12:58:35 -0800 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2015-01-26 13:37:18 -0800 |
| commit | d69911a68c865b152a067feaa45e98e6bb0f655b (patch) | |
| tree | 521455763dbd6c013aa90cb4fa5dc1ce302be5a8 /arch/x86/tools/calc_run_size.sh | |
| parent | mm: page_alloc: embed OOM killing naturally into allocation slowpath (diff) | |
| download | linux-dev-d69911a68c865b152a067feaa45e98e6bb0f655b.tar.xz linux-dev-d69911a68c865b152a067feaa45e98e6bb0f655b.zip | |
x86, build: replace Perl script with Shell script
Commit e6023367d779 ("x86, kaslr: Prevent .bss from overlaping initrd")
added Perl to the required build environment. This reimplements in
shell the Perl script used to find the size of the kernel with bss and
brk added.
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Rob Landley <rob@landley.net>
Acked-by: Rob Landley <rob@landley.net>
Cc: Anca Emanuel <anca.emanuel@gmail.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Junjie Mao <eternal.n08@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
| -rw-r--r-- | arch/x86/tools/calc_run_size.sh | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/arch/x86/tools/calc_run_size.sh b/arch/x86/tools/calc_run_size.sh new file mode 100644 index 000000000000..1a4c17bb3910 --- /dev/null +++ b/arch/x86/tools/calc_run_size.sh @@ -0,0 +1,42 @@ +#!/bin/sh +# +# Calculate the amount of space needed to run the kernel, including room for +# the .bss and .brk sections. +# +# Usage: +# objdump -h a.out | sh calc_run_size.sh + +NUM='\([0-9a-fA-F]*[ \t]*\)' +OUT=$(sed -n 's/^[ \t0-9]*.b[sr][sk][ \t]*'"$NUM$NUM$NUM$NUM"'.*/\1\4/p') +if [ -z "$OUT" ] ; then + echo "Never found .bss or .brk file offset" >&2 + exit 1 +fi + +OUT=$(echo ${OUT# }) +sizeA=$(printf "%d" 0x${OUT%% *}) +OUT=${OUT#* } +offsetA=$(printf "%d" 0x${OUT%% *}) +OUT=${OUT#* } +sizeB=$(printf "%d" 0x${OUT%% *}) +OUT=${OUT#* } +offsetB=$(printf "%d" 0x${OUT%% *}) + +run_size=$(( $offsetA + $sizeA + $sizeB )) + +# BFD linker shows the same file offset in ELF. +if [ "$offsetA" -ne "$offsetB" ] ; then + # Gold linker shows them as consecutive. + endB=$(( $offsetB + $sizeB )) + if [ "$endB" != "$run_size" ] ; then + printf "sizeA: 0x%x\n" $sizeA >&2 + printf "offsetA: 0x%x\n" $offsetA >&2 + printf "sizeB: 0x%x\n" $sizeB >&2 + printf "offsetB: 0x%x\n" $offsetB >&2 + echo ".bss and .brk are non-contiguous" >&2 + exit 1 + fi +fi + +printf "%d\n" $run_size +exit 0 |