2015-11-02 19:33:29

by Steven Rostedt

Subject: Re: [PATCH 1/3] recordmcount: fix endianness handling bug for nop_mcount

On Sat, 31 Oct 2015 10:07:38 +0800
libin <[email protected]> wrote:

>
>
> on 2015/10/30 22:35, Sergei Shtylyov wrote:
> > Hello.
> >
> > On 10/30/2015 11:31 AM, Li Bin wrote:
> >
> >> In nop_mcount, shdr->sh_offset and welp->r_offset should handle
> >> endianness properly, otherwise it will trigger Segmentation fault
> >> if the recordmcount main and file.o have different endianness.
> >>
> >> Cc: <[email protected]> # 3.0+
> >> Signed-off-by: Li Bin <[email protected]>
> >> ---
> >> scripts/recordmcount.h | 5 +++--
> >> 1 file changed, 3 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h
> >> index 49b582a..dda9dba 100644
> >> --- a/scripts/recordmcount.h
> >> +++ b/scripts/recordmcount.h
> >> @@ -376,8 +376,9 @@ static void nop_mcount(Elf_Shdr const *const relhdr,
> >> mcountsym = get_mcountsym(sym0, relp, str0);
> >>
> >> if (mcountsym == Elf_r_sym(relp) && !is_fake_mcount(relp)) {
> >> - if (make_nop)
> >> - ret = make_nop((void *)ehdr, shdr->sh_offset + relp->r_offset);
> >> + if (make_nop) {
> >> + ret = make_nop((void *)ehdr, _w(shdr->sh_offset) + _w(relp->r_offset));
> >> + }
> >
> > {} not needed here.
>
> Oh, yes. When I cleaned the debugging code, forgot delete the {}.
>
>

Is there a new version of this patch, or should I just take this and
remove the '{}' myself?

I already added the x86 update.

-- Steve

2015-11-03 01:00:25

by Li Bin

Subject: [PATCH] recordmcount: fix endianness handling bug for nop_mcount

In nop_mcount, shdr->sh_offset and welp->r_offset should handle
endianness properly, otherwise it will trigger Segmentation fault
if the recordmcount main and file.o have different endianness.

Cc: <[email protected]> # 3.0+
Signed-off-by: Li Bin <[email protected]>
---
scripts/recordmcount.h | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/scripts/recordmcount.h b/scripts/recordmcount.h
index 49b582a..b9897e2 100644
--- a/scripts/recordmcount.h
+++ b/scripts/recordmcount.h
@@ -377,7 +377,7 @@ static void nop_mcount(Elf_Shdr const *const relhdr,

if (mcountsym == Elf_r_sym(relp) && !is_fake_mcount(relp)) {
if (make_nop)
- ret = make_nop((void *)ehdr, shdr->sh_offset + relp->r_offset);
+ ret = make_nop((void *)ehdr, _w(shdr->sh_offset) + _w(relp->r_offset));
if (warn_on_notrace_sect && !once) {
printf("Section %s has mcount callers being ignored\n",
txtname);
--
1.7.1