From: "Maciej W. Rozycki" <macro@linux-mips.org>
To: Mark Kettenis <mark.kettenis@xs4all.nl>
Cc: drow@false.org, binutils@sources.redhat.com
Subject: Re: MIPS, strip --only-keep-debug & an infinite loop
Date: Mon, 23 May 2005 20:51:00 -0000 [thread overview]
Message-ID: <Pine.LNX.4.61L.0505232051440.4541@blysk.ds.pg.gda.pl> (raw)
In-Reply-To: <Pine.LNX.4.61L.0505181157111.19170@blysk.ds.pg.gda.pl>
On Wed, 18 May 2005, Maciej W. Rozycki wrote:
> > Hmm, this seems to have fallen between the cracks. Anyway, here is a
> > patch that seems to work for me. It seems to fix objcopy/strip
> > --only-keep-debug and avoids the infinite loop. However, I do think
> > the SEC_HAS_CONTENTS check should probably be applied to other faked
> > sections too.
>
> It hasn't really fallen -- it's just my lack of time, sigh... Thanks for
> looking into it -- I'll see if I can test it before 2.16.1.
Well, I've had a look at the patch and I found out just returning a
failure is inadequate for these functions. For
_bfd_mips_elf_section_processing() it's simply ignored. For
_bfd_mips_elf_section_from_shdr() it leads to such a damaged object being
completely rejected, which prevents doing `objdump' or fixing it with
another run of `strip --only-keep-debug' and is probably an overkill. In
neither case any useful diagnostics is available. Therefore I've
rewritten these changes to provide some diagnostics and attempt to
continue anyway.
For _bfd_mips_elf_fake_sections() I agree appropriate handling of all
special sections is desirable.
This has been checked not to cause any regressions in the test suite run
for mipsel-linux-gnu natively.
2005-05-23 Mark Kettenis <kettenis@gnu.org>
Maciej W. Rozycki <macro@linux-mips.org>
* elfxx-mips.c (_bfd_mips_elf_section_processing): Warn and
stop processing of options if one of invalid size is
encountered.
(_bfd_mips_elf_section_from_shdr): Likewise.
(_bfd_mips_elf_fake_sections): Reset the type of empty special
sections.
OK to apply? Since it fixes a fatal problem, I'm asking for permission
for 2.16.1, too.
Maciej
binutils-2.16-mips-fake-sections.patch
diff -up --recursive --new-file binutils-2.16.macro/bfd/elfxx-mips.c binutils-2.16/bfd/elfxx-mips.c
--- binutils-2.16.macro/bfd/elfxx-mips.c 2005-04-19 18:37:04.000000000 +0000
+++ binutils-2.16/bfd/elfxx-mips.c 2005-05-22 06:08:02.000000000 +0000
@@ -4990,6 +4990,13 @@ _bfd_mips_elf_section_processing (bfd *a
bfd_mips_elf_swap_options_in (abfd, (Elf_External_Options *) l,
&intopt);
+ if (intopt.size < sizeof (Elf_External_Options))
+ {
+ (*_bfd_error_handler)
+ (_("%B: Warning: bad `%s' option size %u smaller than its header"),
+ abfd, MIPS_ELF_OPTIONS_SECTION_NAME (abfd), intopt.size);
+ break;
+ }
if (ABI_64_P (abfd) && intopt.kind == ODK_REGINFO)
{
bfd_byte buf[8];
@@ -5202,6 +5209,13 @@ _bfd_mips_elf_section_from_shdr (bfd *ab
bfd_mips_elf_swap_options_in (abfd, (Elf_External_Options *) l,
&intopt);
+ if (intopt.size < sizeof (Elf_External_Options))
+ {
+ (*_bfd_error_handler)
+ (_("%B: Warning: bad `%s' option size %u smaller than its header"),
+ abfd, MIPS_ELF_OPTIONS_SECTION_NAME (abfd), intopt.size);
+ break;
+ }
if (ABI_64_P (abfd) && intopt.kind == ODK_REGINFO)
{
Elf64_Internal_RegInfo intreg;
@@ -5240,8 +5254,10 @@ bfd_boolean
_bfd_mips_elf_fake_sections (bfd *abfd, Elf_Internal_Shdr *hdr, asection *sec)
{
register const char *name;
+ unsigned int sh_type;
name = bfd_get_section_name (abfd, sec);
+ sh_type = hdr->sh_type;
if (strcmp (name, ".liblist") == 0)
{
@@ -5343,6 +5359,12 @@ _bfd_mips_elf_fake_sections (bfd *abfd,
hdr->sh_entsize = 8;
}
+ /* In the unlikely event a special section is empty it has to lose its
+ special meaning. This may happen e.g. when using `strip' with the
+ "--only-keep-debug" option. */
+ if (sec->size > 0 && !(sec->flags & SEC_HAS_CONTENTS))
+ hdr->sh_type = sh_type;
+
/* The generic elf_fake_sections will set up REL_HDR using the default
kind of relocations. We used to set up a second header for the
non-default kind of relocations here, but only NewABI would use
next prev parent reply other threads:[~2005-05-23 20:36 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-04-28 23:02 Mark Kettenis
2005-04-29 12:30 ` Maciej W. Rozycki
2005-04-29 13:02 ` Thiemo Seufer
2005-04-29 13:06 ` Maciej W. Rozycki
2005-04-29 13:47 ` Thiemo Seufer
2005-04-29 13:51 ` Daniel Jacobowitz
2005-04-29 14:06 ` Maciej W. Rozycki
2005-04-29 14:07 ` Daniel Jacobowitz
2005-04-29 16:13 ` Maciej W. Rozycki
2005-05-01 1:50 ` Daniel Jacobowitz
2005-05-01 16:16 ` Maciej W. Rozycki
2005-05-01 16:17 ` Daniel Jacobowitz
2005-05-17 23:20 ` Mark Kettenis
2005-05-18 13:36 ` Maciej W. Rozycki
2005-05-18 17:32 ` Mark Kettenis
2005-05-23 20:51 ` Maciej W. Rozycki [this message]
2005-05-25 23:35 ` Mark Kettenis
2005-05-26 16:27 ` Eric Christopher
2005-04-29 15:16 ` Mark Kettenis
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=Pine.LNX.4.61L.0505232051440.4541@blysk.ds.pg.gda.pl \
--to=macro@linux-mips.org \
--cc=binutils@sources.redhat.com \
--cc=drow@false.org \
--cc=mark.kettenis@xs4all.nl \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).