libdw now always needs -lpthread and -ld even when BUILD_STATIC.
BUILD_STATIC is only used when doing a gcov enabled build.
Enable gcov coverage also for debuginfod.

Signed-off-by: Mark Wielaard <mark@klomp.org>

A corrupt ELF file could contain a .strtab section that wasn't
properly zero terminated. If so we could add a non-terminated string
to the dwelf_strtab functions, which could then crash because they
would read past the .strtab section data.

https://sourceware.org/bugzilla/show_bug.cgi?id=25069

Signed-off-by: Mark Wielaard <mark@klomp.org>

If the sh_entsize of the symver section was bogus (bigger than necessary)
then some bogus data would be written out (except that then fails because
pwrite would probably fail). Fix that by ignoring the bogus sh_entsize
and use the actual symver data size.

https://sourceware.org/bugzilla/show_bug.cgi?id=25077

Signed-off-by: Mark Wielaard <mark@klomp.org>

unstrip tries to preserve any allocated section offset in an
executable or shared library. If the offset is extremely large that
would cause the disk to fill up because we will write out a file with
lots of padding to put the section contents at that particular
offset. Add a sanity check that makes sure we just error out if there
is such a bogus offset by checking that no offset is larger than the
original ELF file size.

https://sourceware.org/bugzilla/show_bug.cgi?id=25083

Signed-off-by: Mark Wielaard <mark@klomp.org>

There were various ways to crash eu-unstrip with bad ELF input
data. Add various tests against bad data and allocate some structures
on the heap instead of on the stack.

https://sourceware.org/bugzilla/show_bug.cgi?id=25082

Signed-off-by: Mark Wielaard <mark@klomp.org>

When an input file cannot be opened, include its name
into the error diagnostics.

Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>

It is already possible to select the symbol table to print by name,
using --symbols=SECTION. This allows printing the dynamic symbol table
with --symbols=.dynsym. binutils readelf allows printing just the
dynamic symbol table by type using --dyn-sym. Add the same option
and document it. Also add a testcase to show --symbols=.dynsym and
--dyn-sym produce the same output.

Signed-off-by: Mark Wielaard <mark@klomp.org>

The readelf code did parse section numbers, but then failed to actually
dump the section found. Fixed by actually calling the dump function
(either the hex or string variant). Add testcase for readelf -x num.

Signed-off-by: Mark Wielaard <mark@klomp.org>

If there are just a handful of symbols then memory for them is
allocated on the stack, otherwise the memory is malloced. So before
freeing the memory we need to check the number of entries to know if
the memory was heap allocated or not. But since not all entries might
be used we might have decreased the number of entries to the number
we will actually show. Remember the original symbol entries to not
have a memory leak.

Signed-off-by: Mark Wielaard <mark@klomp.org>

Currently, architecture-specific code for libebl exists in separate
libebl_$ARCH.so libraries which libebl loads with dlopen() at runtime.
This makes it impossible to have standalone, statically-linked binaries
which use libdwfl if they depend on any architecture-specific
functionality. Additionally, when these libraries cannot be found, the
failure modes are non-obvious. So, let's get rid of libebl_$arch.so and
move it all into libdw.so/libdw.a, which simplifies things considerably.

Signed-off-by: Omar Sandoval <osandov@fb.com>