[PATCH 08/10] strip,unstrip: Use and set shdrstrndx consistently.
Mark Wielaard
mark@klomp.org
Thu Sep 13 23:02:00 GMT 2018
In various places in strip we used e_shstrndx instead of shdrstrndx and we
didn't setup the shdrstrndx for the debug file. In unstrip we forgot to copy
the shdrstrndx in case the -o output option was used.
Added a new testcase that adds many sections to a testfile and runs strip, elflint,
unstrip and elfcmp.
Signed-off-by: Mark Wielaard <mark@klomp.org>
---
src/ChangeLog | 7 +++++
src/strip.c | 43 ++++++++++++++++++++++++++---
src/unstrip.c | 21 +++++++++++++-
tests/ChangeLog | 6 ++++
tests/Makefile.am | 4 +--
tests/run-strip-test-many.sh | 66 ++++++++++++++++++++++++++++++++++++++++++++
6 files changed, 140 insertions(+), 7 deletions(-)
create mode 100755 tests/run-strip-test-many.sh
diff --git a/src/ChangeLog b/src/ChangeLog
index a093a73..524c81a 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,12 @@
2018-09-13 Mark Wielaard <mark@klomp.org>
+ * strip.c (handle_elf): Check against shstrndx, not e_shstrndx.
+ Explicitly set shdrstrndx for debug file.
+ * unstrip.c (copy_elf): Explicitly copy shstrndx.
+ (find_alloc_sections_prelink): Document shnum usage.
+
+2018-09-13 Mark Wielaard <mark@klomp.org>
+
* elflint.c (check_elf_header): Use shnum instead of e_shnum for all
checks.
(check_symtab): Use shstrndx instead of e_shstrndx to get section
diff --git a/src/strip.c b/src/strip.c
index dc71236..4a3db1b 100644
--- a/src/strip.c
+++ b/src/strip.c
@@ -820,7 +820,7 @@ handle_elf (int fd, Elf *elf, const char *prefix, const char *fname,
: (ebl_section_strip_p (ebl, &shdr_info[cnt].shdr,
shdr_info[cnt].name, remove_comment,
remove_debug)
- || cnt == ehdr->e_shstrndx
+ || cnt == shstrndx
|| section_name_matches (remove_secs, shdr_info[cnt].name)))
{
/* The user might want to explicitly keep this one. */
@@ -1081,7 +1081,7 @@ handle_elf (int fd, Elf *elf, const char *prefix, const char *fname,
&& shdr_info[cnt].debug_data == NULL
&& shdr_info[cnt].shdr.sh_type != SHT_NOTE
&& shdr_info[cnt].shdr.sh_type != SHT_GROUP
- && cnt != ehdr->e_shstrndx);
+ && cnt != shstrndx);
/* Set the section header in the new file. */
GElf_Shdr debugshdr = shdr_info[cnt].shdr;
@@ -1134,7 +1134,42 @@ handle_elf (int fd, Elf *elf, const char *prefix, const char *fname,
debugehdr->e_version = ehdr->e_version;
debugehdr->e_entry = ehdr->e_entry;
debugehdr->e_flags = ehdr->e_flags;
- debugehdr->e_shstrndx = ehdr->e_shstrndx;
+
+ size_t shdrstrndx;
+ if (elf_getshdrstrndx (elf, &shdrstrndx) < 0)
+ {
+ error (0, 0, gettext ("%s: error while getting shdrstrndx: %s"),
+ fname, elf_errmsg (-1));
+ result = 1;
+ goto fail_close;
+ }
+
+ if (shstrndx < SHN_LORESERVE)
+ debugehdr->e_shstrndx = shdrstrndx;
+ else
+ {
+ debugehdr->e_shstrndx = SHN_XINDEX;
+ Elf_Scn *scn0 = elf_getscn (debugelf, 0);
+ GElf_Shdr shdr0_mem;
+ GElf_Shdr *shdr0 = gelf_getshdr (scn0, &shdr0_mem);
+ if (shdr0 == NULL)
+ {
+ error (0, 0, gettext ("%s: error getting zero section: %s"),
+ debug_fname, elf_errmsg (-1));
+ result = 1;
+ goto fail_close;
+ }
+
+ shdr0->sh_link = shdrstrndx;
+ if (gelf_update_shdr (scn0, shdr0) == 0)
+ {
+ error (0, 0, gettext ("%s: error while updating zero section: %s"),
+ debug_fname, elf_errmsg (-1));
+ result = 1;
+ goto fail_close;
+ }
+
+ }
if (unlikely (gelf_update_ehdr (debugelf, debugehdr) == 0))
{
@@ -1187,7 +1222,7 @@ handle_elf (int fd, Elf *elf, const char *prefix, const char *fname,
the .shstrtab section which we would add again. */
bool removing_sections = !(cnt == idx
|| (cnt == idx + 1
- && shdr_info[ehdr->e_shstrndx].idx == 0));
+ && shdr_info[shstrndx].idx == 0));
if (output_fname == NULL && !removing_sections)
goto fail_close;
diff --git a/src/unstrip.c b/src/unstrip.c
index ec46c95..e6f0947 100644
--- a/src/unstrip.c
+++ b/src/unstrip.c
@@ -239,8 +239,27 @@ copy_elf (Elf *outelf, Elf *inelf)
ELF_CHECK (gelf_newehdr (outelf, gelf_getclass (inelf)),
_("cannot create ELF header: %s"));
+ size_t shstrndx;
+ ELF_CHECK (elf_getshdrstrndx (inelf, &shstrndx) == 0,
+ _("cannot get shdrstrndx:%s"));
+
GElf_Ehdr ehdr_mem;
GElf_Ehdr *ehdr = gelf_getehdr (inelf, &ehdr_mem);
+ if (shstrndx < SHN_LORESERVE)
+ ehdr->e_shstrndx = shstrndx;
+ else
+ {
+ ehdr->e_shstrndx = SHN_XINDEX;
+ Elf_Scn *scn0 = elf_getscn (outelf, 0);
+ GElf_Shdr shdr0_mem;
+ GElf_Shdr *shdr0 = gelf_getshdr (scn0, &shdr0_mem);
+ ELF_CHECK (shdr0 != NULL,
+ _("cannot get new zero section: %s"));
+ shdr0->sh_link = shstrndx;
+ ELF_CHECK (gelf_update_shdr (scn0, shdr0),
+ _("cannot update new zero section: %s"));
+ }
+
ELF_CHECK (gelf_update_ehdr (outelf, ehdr),
_("cannot copy ELF header: %s"));
@@ -1025,7 +1044,7 @@ find_alloc_sections_prelink (Elf *debug, Elf_Data *debug_shstrtab,
_("cannot read '.gnu.prelink_undo' section: %s"));
uint_fast16_t phnum;
- uint_fast16_t shnum;
+ uint_fast16_t shnum; /* prelink doesn't handle > SHN_LORESERVE. */
if (ehdr.e32.e_ident[EI_CLASS] == ELFCLASS32)
{
phnum = ehdr.e32.e_phnum;
diff --git a/tests/ChangeLog b/tests/ChangeLog
index 33fee35..4e8b814 100644
--- a/tests/ChangeLog
+++ b/tests/ChangeLog
@@ -1,5 +1,11 @@
2018-09-13 Mark Wielaard <mark@klomp.org>
+ * run-strip-test-many.sh: New test.
+ * Makefile.am (TESTS): Add run-strip-test-many.sh.
+ (EXTRA_DIST): Likewise.
+
+2018-09-13 Mark Wielaard <mark@klomp.org>
+
* run-typeiter-many.sh: New test.
* Makefile.am (TESTS): Add run-typeiter-many.sh.
(EXTRA_DIST): Likewise.
diff --git a/tests/Makefile.am b/tests/Makefile.am
index d8ebd03..74c477e 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -156,7 +156,7 @@ TESTS = run-arextract.sh run-arsymtest.sh run-ar.sh newfile test-nlist \
run-reloc-bpf.sh \
run-next-cfi.sh run-next-cfi-self.sh \
run-copyadd-sections.sh run-copymany-sections.sh \
- run-typeiter-many.sh
+ run-typeiter-many.sh run-strip-test-many.sh
if !BIARCH
export ELFUTILS_DISABLE_BIARCH = 1
@@ -408,7 +408,7 @@ EXTRA_DIST = run-arextract.sh run-arsymtest.sh run-ar.sh \
testfile-riscv64.bz2 testfile-riscv64-s.bz2 \
testfile-riscv64-core.bz2 \
run-copyadd-sections.sh run-copymany-sections.sh \
- run-typeiter-many.sh
+ run-typeiter-many.sh run-strip-test-many.sh
if USE_VALGRIND
valgrind_cmd='valgrind -q --leak-check=full --error-exitcode=1'
diff --git a/tests/run-strip-test-many.sh b/tests/run-strip-test-many.sh
new file mode 100755
index 0000000..9a9657c
--- /dev/null
+++ b/tests/run-strip-test-many.sh
@@ -0,0 +1,66 @@
+#! /bin/sh
+# Copyright (C) 2018 Red Hat, Inc.
+# This file is part of elfutils.
+#
+# This file is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# elfutils is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+. $srcdir/test-subr.sh
+
+# Use the original file from run-strip-test.sh but with many sections
+testfiles testfile
+tempfiles testfile.strip testfile.debug testfile.unstrip
+
+echo "Adding sections to testfile"
+testrun ${abs_builddir}/addsections 65535 testfile
+
+echo "Testing strip -o"
+testrun ${abs_top_builddir}/src/strip -o testfile.strip -f testfile.debug testfile
+
+# Do the parts check out?
+echo "elflint testfile.strip"
+testrun ${abs_top_builddir}/src/elflint --gnu -q testfile.strip
+echo "elflint testfile.debug"
+testrun ${abs_top_builddir}/src/elflint --gnu -q -d testfile.debug
+
+# Now test unstrip recombining those files.
+echo "unstrip"
+testrun ${abs_top_builddir}/src/unstrip -o testfile.unstrip testfile.strip testfile.debug
+echo "elfcmp"
+testrun ${abs_top_builddir}/src/elfcmp testfile testfile.unstrip
+
+# test strip -g
+echo "Testing strip -g"
+testrun ${abs_top_builddir}/src/strip -g -o testfile.strip -f testfile.debug testfile
+
+# Do the parts check out?
+echo "elflint testfile.strip"
+testrun ${abs_top_builddir}/src/elflint --gnu -q testfile.strip
+echo "elflint testfile.debug"
+testrun ${abs_top_builddir}/src/elflint --gnu -q -d testfile.debug
+
+# Now strip "in-place" and make sure it is smaller.
+echo "TEsting strip in-place"
+SIZE_original=$(stat -c%s testfile)
+echo "original size $SIZE_original"
+
+testrun ${abs_top_builddir}/src/strip testfile
+SIZE_stripped=$(stat -c%s testfile)
+echo "stripped size $SIZE_stripped"
+test $SIZE_stripped -lt $SIZE_original ||
+ { echo "*** failure in-place strip file not smaller $original"; exit 1; }
+
+echo "elflint in-place"
+testrun ${abs_top_builddir}/src/elflint --gnu -q testfile
+
+exit 0
--
1.8.3.1
More information about the Elfutils-devel
mailing list