David Malcolm [Fri, 23 Feb 2018 14:54:02 +0000 (09:54 -0500)]
Explicitly qualify specializations of elfutils::to_string
I attempted to build the "dwarflint" branch with gcc 7.3.1 , but ran
into various problems of the form:
c++/known.cc:220:1: error: explicit specialization of ‘template<class type> std::__cxx11::string elfutils::to_string(const type&)’ outside its namespace must use a nested-name-specifier [-fpermissive]
to_string<dwarf::dwarf_enum> (const dwarf::dwarf_enum &value)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~
The fix appears to be trivial.
Signed-off-by: David Malcolm <dmalcolm@redhat.com>
* dwarflint/tests: Update all scripts and makefiles to work
with current test environment.
* dwarflint/Makefile.am: Add support for dwarflint testing.
* tests/test-subr.sh: Update to be used in dwarflint/tests.
* tests/test-wrapper.sh: Likewise.
* tests/run-dwarflint-self.sh: Return back into tests/.
Signed-off-by: Djordje Todorovic <djordje.todorovic@rt-rk.com> Signed-off-by: Mark Wielaard <mark@klomp.org>
Mark Wielaard [Mon, 2 Oct 2017 14:06:30 +0000 (16:06 +0200)]
C++ build fixes.
Add AX_CXX_COMPILE_STDCXX_11 and AX_CXX_COMPILE_STDCXX from the
autoconf-archive. Use it in configure.ac to make sure we get a
C++11 capable compiler. Add various c++ sources to libdw/Makefile.am.
Change INCLUDES in dwarflint/Makefile.am to AM_CPPFLAGS to support
newer automake.
Mark Wielaard [Tue, 3 Oct 2017 21:08:01 +0000 (23:08 +0200)]
libdw: Define LIBDW_CIE_ID and use it in dwarf_cfi_cie_p.
dwarf_cfi_cie_p used DW_CIE_ID_64 from dwarf.h which meant you had
to include dwarf.h just to use the dwarf_cfi_cie_p macros. Just define
the constant as LIBDW_CIE_ID in libdw.h to keep it independent.
Ulf Hermann [Fri, 18 Aug 2017 12:05:10 +0000 (14:05 +0200)]
Make sure packed structs follow the gcc memory layout
gcc defaults to using struct layouts that follow the native conventions,
even if __attribute__((packed)) is given. In order to get the layout we
expect, we need to tell gcc to always use the gcc struct layout, at
least for packed structs. To do this, we can use the gcc_struct
attribute.
This is important, not only for porting to windows, but also potentially
for other platforms, as the bugs resulting from struct layout
differences are rather subtle and hard to find.
Mark Wielaard [Sun, 10 Sep 2017 22:12:31 +0000 (00:12 +0200)]
ar: Check whether ar header values fit.
When compiling with -O3 gcc finds an interesting error:
src/ar.c: In function ‘do_oper_insert’:
src/ar.c:1077:56: error: ‘%-*ld’ directive output may be truncated writing between 6 and 10 bytes into a region of size 7 [-Werror=format-truncation=]
snprintf (tmpbuf, sizeof (tmpbuf), ofmt ? "%-*lo" : "%-*ld", bufsize, val);
^~~~~
The problem is that the ar header values have to fit in a limited
(not zero terminated) string. We should check the snprintf return
value to see if the values are representable.
Also make ar valgrind and ubsan clean and add a minimal sanity test.
Reported-by: Matthias Klose <doko@ubuntu.com> Signed-off-by: Mark Wielaard <mark@klomp.org>
Ulf Hermann [Fri, 18 Aug 2017 15:20:02 +0000 (17:20 +0200)]
Cast pid_t to long long when printing
We don't know sizeof(pid_t) as it's not specified in any standard. In
order to still print it, we cast to long long, the largest integer type
we can easily print.
Signed-off-by: Ulf Hermann <ulf.hermann@qt.io> Signed-off-by: Mark Wielaard <mark@klomp.org>
Ulf Hermann [Fri, 18 Aug 2017 15:03:50 +0000 (17:03 +0200)]
On non-linux systems, don't use native signal numbers
We assume core files from linux systems, so we should use the linux
version of the signals when reading them. Other OS might have different
signal numbers.
Ulf Hermann [Fri, 18 Aug 2017 13:17:38 +0000 (15:17 +0200)]
Drop -rdynamic from deleted-lib.so link step
-rdynamic is meant for ELF objects that need to export internal
symbols to libraries they link to, but deleted-lib.so does not link to
anything else and doesn't have any internal symbols.
Note that the "deleted" test program does link to deleted-lib.so, but
deleted-lib.so being a shared object, will automatically export the
(non-hidden) "libfunc" symbol anyway.
Ulf Hermann [Fri, 18 Aug 2017 11:06:36 +0000 (13:06 +0200)]
Check if gcc complains about __attribute__ (visibility(..))
If so, define attribute_hidden to be empty. Also, use attribute_hidden
in all places where we hide symbols. If this attribute is missing, it
simply means that we cannot hide private symbols in the binary using
attributes. This disables some optimizations and may increase the risk
of symbol name clashes with other libraries, but is not fatal.
However, we still employ linker version scripts to explicitly define
the exported symbols. This serves much of the same purpose. Also, as
all our symbols are prefixed with the library name, and "__" for
private ones, the chance of clashes is low anyway.
Ulf Hermann [Fri, 18 Aug 2017 10:41:11 +0000 (12:41 +0200)]
Check for -z,defs, -z,relro, -fPIC, -fPIE before using them
Those flags are not available on all platforms, and omitting them when
not available will not cause any harm. In particular:
-z,defs disallows undefined symbols in object files. This option is
unsupported if the target binary format enforces the same condition
already. Furthermore it is only a compile time sanity check. When it is
omitted, the same binary is produced.
-z,relro instructs the loader to mark sections read-only after loading
the library, where possible. This is a hardening mechanism. If it is
unavailable, the functionality of the code is not affected in any way.
-fPIC instructs the compiler to produce position independent code. While
this is preferable to relocatable code, relocatable code also works and
may even be faster. Relocatable code might just be loaded into memory
multiple times for different processes.
-fPIE is the same thing as -fPIC for executables rather than shared
libraries.
Dmitry V. Levin [Tue, 8 Aug 2017 16:06:16 +0000 (19:06 +0300)]
tests: robustify run-strip-nothing.sh against unstripped libc_nonshared.a
When glibc's libc_nonshared.a contains objects with debug info,
this debug info is leaked into every output file produced by gcc.
Change run-strip-nothing.sh to use "gcc -s" instead of plain "gcc"
for producing objects without debug info.
Mark Wielaard [Wed, 26 Jul 2017 21:02:18 +0000 (23:02 +0200)]
libdw: Add DW_MACRO constants and DW_MACRO_GNU compatibility defines.
Accept version 5 .debug_macro format, which is identical to the GNU
version 4 format. No real support yet for the new supplementary object
file (sup) and indirect string references (strx). GCC doesn't generate
them yet. readelf does recognize them, but doesn't try to decode them.
dwarf_getmacros currently rejects the new formats.
Mark Wielaard [Wed, 26 Jul 2017 20:54:59 +0000 (22:54 +0200)]
libdw: Handle DWARF5 immutable, packed and shared in dwarf_peel_type.
Also update the documentation to explain that any type alias or modifier
that doesn't modify, change the structural layout or the way to access
the underlying type is peeled. Explicitly mention pointer and reference
types as examples of modifiers that don't obey that rule and so aren't
peeled.
Mark Wielaard [Wed, 26 Jul 2017 16:06:21 +0000 (18:06 +0200)]
libdw: Add dwarf_default_lower_bound.
Add dwarf_default_lower_bound to get the default lower bound for a language
when not given as attribute for an subrange type. Implementation extracted
from dwarf_aggregate_size.
Add a test to check all known language codes are handled.
Mark Wielaard [Tue, 25 Jul 2017 13:29:10 +0000 (15:29 +0200)]
libdw: Add DWARF5 attributes.
Add new DWARF5 attribute constant names to the attributes enum.
Also add reserved comments between non-consecutive (reserved) numbers.
Remove DW_AT_subscr_data, DW_AT_element_list and DW_AT_member from the
enum list and turn them into compatibility defines because they are
not part of DWARF2+. That way code that directly references them still
compiles but they won't show up in known-dwarf.h.
Since POWER8, PowerPC 64 supports Hardware Transactional Memory, which has
three special purpose registers associated to it: tfhar, tfiar, and texasr.
This commit add HTM SPRs set as known note type so it's possible to use
'readelf --notes' to inspect the HTM SPRs in a coredump file generated in
such a machines.
Mark Wielaard [Thu, 20 Jul 2017 20:34:29 +0000 (22:34 +0200)]
strip: Deal with ARM data marker symbols pointing to debug sections.
ARM data marker symbols "$d" indicate the start of a sequence of data
items in a section. For data only sections no data marker symbol is
necessary, but may be put pointing to the start of the section.
binutils however has a bug which places a data marker symbol somewhere
inside the section (at least for .debug_frame).
https://sourceware.org/bugzilla/show_bug.cgi?id=21809
When strip finds a symbol pointing to a debug section that would be
put into the .debug file then it will copy over the whole symbol table.
This isn't necessary because the symbol is redundant.
Add an ebl hook to recognize data marker symbols with implementations
for arm and aarch64. Use it in strip to strip such symbols from the
symbol table if they point to a debug section.
Mark Wielaard [Tue, 18 Jul 2017 12:12:36 +0000 (14:12 +0200)]
backends: Don't depend on linux/bpf.h to compile bpf disassembler.
We only need a few constants and one structure definition from linux/bpf.
Just define those in a local lib/bpf.h file. This makes sure the bpf
disassembler is always build and included even when elfutils is build
on older GNU/Linux systems (and even on other platforms).
Ulf Hermann [Fri, 17 Feb 2017 15:11:28 +0000 (16:11 +0100)]
Unify linking of libasm, libelf, libdw, backends
Link them all with -z,defs,-z,relro,--no-undefined, provide complete
dependencies for the link steps, and add libeu.a to each one. libeu.a
contains useful library functionality that each of them might use. The
linker will strip unneeded symbols, so linking it in won't hurt even if
none of the functions are used.
Mark Wielaard [Mon, 17 Jul 2017 15:26:25 +0000 (17:26 +0200)]
backends: Swap sys/ptrace.h and asm/ptrace.h include order on s390.
glibc 2.26 changed the sys/ptrace.h header so that it cannot be included
after asm/ptrace.h. We still need to include the kernel asm/ptrace.h for
the ptrace_area definition. Including it after sys/ptrace.h works against
both old and new glibc.
Mark Wielaard [Fri, 14 Jul 2017 15:09:40 +0000 (17:09 +0200)]
strip: Add --keep-section=SECTION and --remove-section=SECTION.
Adds two new output options:
--keep-section=SECTION Keep the named section. SECTION is an extended
wildcard pattern. May be given more than once.
--remove-section=SECTION Remove the named section. SECTION is an
extended wildcard pattern. May be given more than
once. Only non-allocated sections can be removed.
The --remove-section was already partially implemented, but only for the
.comment section. The short option -R is to be compatible with binutils.
The new testcase makes sure that various combinations of kept/removed
sections pull the correct dependencies into the output and/or debug files.
Mark Wielaard [Wed, 7 Jun 2017 18:32:38 +0000 (20:32 +0200)]
strip: Don't generate empty output file when nothing to do.
If there was nothing to do strip would skip generating a separate
debug file if one was requested, but it would also not finish the
creation of a new output file (with the non-stripped sections).
Also if there was an error any partially created output would be kept.
Make sure that when the -o output file option is given we always generate
a complete output file (except on error). Also make sure that when the -f
debug file option is given it is only generated when it is not empty.
Add testcase run-strip-nothing.sh that tests the various combinations.
Mark Wielaard [Wed, 7 Jun 2017 12:05:36 +0000 (14:05 +0200)]
strip: Make sure old .shstrab is removed when eu-strip recreates it.
Although we always recreate the .shstrtab section for the new output
file we never explicitly assumed it could be removed. It might not be
possible to remove it when the section string table is shared with
a symbol table. But if it is removable we should (and recreate it for
the new section list).
Regression introduced in commit elfutils-0.163-33-gdf7dfab.
"Handle merged strtab/shstrtab string tables in strip and unstrip."
Add extra testcase to explicitly check for this case.
Mark Wielaard [Sun, 21 May 2017 21:33:15 +0000 (23:33 +0200)]
ppc64: Add minimal fallback unwinder.
This adds a minimal fallback unwinder for ppc64[le] in case we cannot find
CFI for a particular address. It simply always sets the program counter to
the link register, picks the previous stack pointer from the backchain,
and the previous link register from the LR save area.
This is enough for some simple situations when we don't have CFI and
seems to work nicely in the case of perf with libdw powerpc support:
https://lkml.org/lkml/2017/5/18/998
Ulf Hermann [Thu, 20 Apr 2017 14:54:26 +0000 (16:54 +0200)]
Make elf section sorting more deterministic
At least one test (dwfl-addr-sect) depends on the order of elf sections
with equal addresses. This is not guaranteed by the code. Compare also
by end address and section index to tell entries apart.
Signed-off-by: Ulf Hermann <ulf.hermann@qt.io> Signed-off-by: Mark Wielaard <mark@klomp.org>
Ulf Hermann [Thu, 20 Apr 2017 12:41:35 +0000 (14:41 +0200)]
Add frame pointer unwinding for aarch64 and relax backtrace testcases.
If we don't find any debug information for a given frame, we usually
cannot unwind any further. However, the binary in question might have
been compiled with frame pointers, in which case we can look up the
well known frame pointer locations in the stack snapshot and use them
to bridge the frames without debug information.
Relax the backtrace core testcases a little by allowing a duplicate
sigusr2 frame or a backtrace ending with an invalid register. Both of
which can happen if the frame pointer unwinder guesses slightly wrong.
Signed-off-by: Ulf Hermann <ulf.hermann@qt.io> Signed-off-by: Mark Wielaard <mark@klomp.org>
Ulf Hermann [Fri, 10 Feb 2017 14:19:40 +0000 (15:19 +0100)]
Add frame pointer unwinding as fallback on x86_64
If we don't find any debug information for a given frame, we usually
cannot unwind any further. However, the binary in question might have
been compiled with frame pointers, in which case we can look up the
well known frame pointer locations in the stack snapshot and use them
to bridge the frames without debug information.
The "unwind" hook is the right place for this as it is so far only
used on s390 and called only after trying to unwind with debug
information.
Mark Wielaard [Tue, 25 Apr 2017 10:41:58 +0000 (12:41 +0200)]
tests: Add core backtracegen check and regen ppc32 backtrace testfiles.
Add a check to check_core to make sure the backtracegen function is
found in the backtrace. This function is in the middle of the backtrace
in the main executable and if not found it means the backtrace was
incomplete or the frame was skipped (which could happen on a bad frame
pointer only unwind).
This showed that the ppc32 backtrace test files were missing DWARF CFI
for the main executable. Regenerated them to include full CFI.
Allowing no symbol resolving at all makes it too hard to see
whether the test actually tests anything.
But do keep "address out of range" as allowed error in check_err.
This can be interpreted as DWARF not available (if end of callstack
marker is missing, which it unfortunately often is missing even if CFI
is available.).
Ulf Hermann [Thu, 20 Apr 2017 14:31:02 +0000 (16:31 +0200)]
Avoid double-including config.h
config.h doesn't have include guards, so including it twice is bad. We
deal with this by checking for PACKAGE_NAME, but only in some places.
Once we start using gnulib, we will need to include config.h before any
gnulib-generated headers. This is problematic if we include it
transitively through our own private headers.
In order to set a clear rule about inclusion of config.h, it is now
included in every .c file as first header, but not in any header. This
will definitely avoid double-inclusion and satisfy the condition that it
has to be included before gnulib headers. It comes at the price of
adding some redundancy, but there is no clean way to avoid this.
Ulf Hermann [Thu, 20 Apr 2017 13:55:47 +0000 (15:55 +0200)]
Make __attribute__ conditional in all installed headers
__attribute__ is a GNU extension. If we want to link against the
libraries using a different compiler, it needs to be disabled. It was
already disabled in libdw.h, and this patch extends this to the other
headers. We move the defines to libelf.h as that is included in all
the others.
Ulf Hermann [Thu, 27 Apr 2017 14:35:23 +0000 (16:35 +0200)]
Fix nesting of braces
The way it was before it didn't actually test if elf_update failed, but
rather did something random. !!(<some number>) is a boolean and boolean
true can be represented as anything non-0, including negative numbers.
Ulf Hermann [Thu, 20 Apr 2017 14:40:30 +0000 (16:40 +0200)]
Avoid signed/unsigned comparison
Some compilers implicitly cast the result of uint_fast16_t *
uint_fast16_t to something signed and then complain about the
comparison to (unsigned) size_t.
Casting phnum to size_t is a good idea anyway as 16bit multiplication
can easily overflow and we are not checking for this.
Ulf Hermann [Thu, 20 Apr 2017 13:47:49 +0000 (15:47 +0200)]
Avoid YESSTR and NOSTR
Those are deprecated and apparently some implementations of nl_langinfo
return empty strings for them. The tests even tested for those empty
strings even though the intention of the code was clearly to output
"yes" or "no" there.
Mark Wielaard [Wed, 19 Apr 2017 15:07:46 +0000 (17:07 +0200)]
libelf: Initialize n to zero in elf_getarsym.
When building with gcc -Os it seems we can inline read_number_entries
but if that function fails then n will not be initialized. GCC seems not
to realize that in that case n won't be used at all. Explicitly initialize
n to zero to prevent a spurious error: 'n' may be used uninitialized in
this function [-Werror=maybe-uninitialized] in that case.
Mark Wielaard [Thu, 30 Mar 2017 10:19:53 +0000 (12:19 +0200)]
libdw: Fix dwarf_peel_type infinite loop.
We were calling dwarf_attr_integrate () in the die in the loop instead of
on the result. Which would cause an infinite loop when die != result.
Add a testcase that explicitly checks this case.
Mark Wielaard [Mon, 27 Mar 2017 22:38:52 +0000 (00:38 +0200)]
elflint: Don't trust sh_entsize when checking hash sections.
Calculate and use the expected entsize instead of relying on the one
given by the ELF file section header. Return early if there isn't enough
data in the section to check the full hash table.
Mark Wielaard [Mon, 27 Mar 2017 15:01:57 +0000 (17:01 +0200)]
libelf: Always update last_offset in updatefile and updatemmap.
When ELF section data was used, but not updated or marked as dirty and
there also existed non-dirty sections and some padding was needed between
the sections (possibly because of alignment) then elf_update might write
"fill" over some of the existing data. This happened because in that case
the last_position was not updated correctly.
Includes a new testcase fillfile that fails before this patch by showing
fill instead of the expected data in some section data. It succeeds with
this patch.
Mark Wielaard [Fri, 24 Mar 2017 14:06:04 +0000 (15:06 +0100)]
libelf: Check compression ratio before trying to allocate output buffer.
The maximum compression factor (http://www.zlib.net/zlib_tech.html) is
1032:1. Add a sanity check for that before trying to allocate lots of
memory and trying to decompress lots of bogus data.
Mark Wielaard [Fri, 24 Mar 2017 13:10:26 +0000 (14:10 +0100)]
Use the empty string for note names with zero size (without any data).
ELF notes can have a zero sized name. In which case there is no data at
all (so also no zero terminator). Make sure to use the empty string for
such notes if the code does not otherwise explicitly check n_namesz.
Mark Wielaard [Fri, 24 Mar 2017 11:15:02 +0000 (12:15 +0100)]
readelf: Fix off by one sanity check in handle_gnu_hash.
We sanity check to make sure we don't index outside the chain array
by testing inner > max_nsyms. But inner is a zero-based index, while
max_nsyms is the maximum number. Change the check to inner >= max_nsyms.
Mark Wielaard [Sun, 12 Feb 2017 20:51:34 +0000 (21:51 +0100)]
libasm: Fix one GCC7 -Wformat-truncation=2 warning.
Make sure that if we have really lots of labels the tempsym doesn't get
truncated because it is too small to hold the whole name.
This doesn't enable -Wformat-truncation=2 or fix other "issues" pointed
out by enabling this warning because there are currently some issues
with it. https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79448
Mark Wielaard [Wed, 15 Feb 2017 13:30:27 +0000 (14:30 +0100)]
backends: Add support for EM_PPC64 GNU_ATTRIBUTES.
ppc64 and ppc64le ELF files can also contain a power specific
.gnu.attributes section. Add support for those and recognize the new
GNU_Power_ABI_FP Single-precision hard float value.
Ulf Hermann [Thu, 16 Feb 2017 11:32:02 +0000 (12:32 +0100)]
Move print_version into printversion.{h|c}
Rename version.c so that the implementation is called after the header
and the header doesn't clash with the toplevel version.h. print_version
depends on argp and is only used in the tools.
Mark Wielaard [Thu, 9 Feb 2017 20:09:54 +0000 (21:09 +0100)]
Add -D_FORTIFY_SOURCE=2 to CFLAGS if possible.
Some distros now add -D_FORTIFY_SOURCE=2 by default and we have missed
some issues in the past caught by it. Add it to CFLAGS if possible.
The configure check will make sure that it doesn't conflict with any
other CFLAGS already defined.
Ulf Hermann [Fri, 10 Feb 2017 14:19:40 +0000 (15:19 +0100)]
Optionally allow unknown symbols in the backtrace tests
This is useful to test unwinding without debug information. The
binaries being examined might still have frame pointers that allow
us to bridge the unknown symbols.
Ulf Hermann [Fri, 10 Feb 2017 14:19:01 +0000 (15:19 +0100)]
Make the backtrace-data test helper more robust
When unwinding by frame pointer the unwinder might ask for invalid
addresses. We don't have to fail the test in this case. In fact
any broken dwarf information can lead to requests for invalid
addresses, also without frame pointer unwinding.
projects / thirdparty / elfutils.git / log
