diff options
| author | Yinghai Lu <yinghai@kernel.org> | 2016-04-29 00:09:08 (GMT) |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-04-29 09:03:30 (GMT) |
| commit | 4abf061bf87bbd856c8d60199b2fba8b8f9b9fd6 (patch) | |
| tree | d7e276656737cc3aa430da52a2791c1104b474d0 /arch/x86/boot | |
| parent | 4d2d542482205d3df1a0852751f5b004cc6390cc (diff) | |
| download | linux-4abf061bf87bbd856c8d60199b2fba8b8f9b9fd6.tar.xz | |
x86/boot: Correctly bounds-check relocations
Relocation handling performs bounds checking on the resulting calculated
addresses. The existing code uses output_len (VO size plus relocs size) as
the max address. This is not right since the max_addr check should stop at
the end of VO and exclude bss, brk, etc, which follows. The valid range
should be VO [_text, __bss_start] in the loaded physical address space.
This patch adds an export for __bss_start in voffset.h and uses it to
set the correct limit for max_addr.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
[ Rewrote the changelog. ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1461888548-32439-7-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/boot')
| -rw-r--r-- | arch/x86/boot/compressed/Makefile | 2 | ||||
| -rw-r--r-- | arch/x86/boot/compressed/misc.c | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index adef26d..75f2233 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -57,7 +57,7 @@ LDFLAGS_vmlinux := -T hostprogs-y := mkpiggy HOST_EXTRACFLAGS += -I$(srctree)/tools/include -sed-voffset := -e 's/^\([0-9a-fA-F]*\) [ABCDGRSTVW] \(_text\|_end\)$$/\#define VO_\2 _AC(0x\1,UL)/p' +sed-voffset := -e 's/^\([0-9a-fA-F]*\) [ABCDGRSTVW] \(_text\|__bss_start\|_end\)$$/\#define VO_\2 _AC(0x\1,UL)/p' quiet_cmd_voffset = VOFFSET $@ cmd_voffset = $(NM) $< | sed -n $(sed-voffset) > $@ diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index bee6238..8f0253d 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -191,7 +191,7 @@ static void handle_relocations(void *output, unsigned long output_len) int *reloc; unsigned long delta, map, ptr; unsigned long min_addr = (unsigned long)output; - unsigned long max_addr = min_addr + output_len; + unsigned long max_addr = min_addr + (VO___bss_start - VO__text); /* * Calculate the delta between where vmlinux was linked to load |