Accept either little-endian or big-endian representation of the ELF
hints magic number in the header of a hints file and convert the
parameters to the native byte-order of the repsective system.
This is a pre-requisite for a planned change to always write the byte
order in little-endian format on all architectures. The only relvant
architecture that uses big-endian data is powerpc64, and it is not
likely that new architectures will choose that representation of data
in memory.
When all supported architectures use little-endian data in the hints
file, the byte swap logic can be enabled for big-endian CPUs at
compile time. Up to that point, there is a very small run-time penalty
that is paid on all systems to check the byte-order of the hints file
and to provide the option to byte-swap the parameters read from the
hints file header.
This commit contains the changes from review D44080 (which had been
split off from this patch for easier review),
Reviewed by: kib
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D44053
(cherry picked from commit 7b77d37a56)
rtld-elf: add some debug print statements
The byte-order independent code has been reported to fail on powerpc64.
Add some more debug statements to help identify the parametrs used and
to verify the correct operation of the byte-swap macros used..
(cherry picked from commit 173953182a)
rtld: fix check for endianess of elf hints file
Don't check if the elf hints file is in host byte order, but check
if it is in little endian by looking at the magic number.
This fixes rtld on big endian platforms.
Reviewed by: se, kib (prior version of the patch)
Fixes: 7b77d37a56 ("rtld-elf: support either byte-order of hints")
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D44472
(cherry picked from commit da2d6e2815)
rtld: reduce debug messages after fix on big-endian hosts
Remove a debug message that had been added to support the debugging
of a mis-detection of the hint files endianness on powerpc64.
MFC after: 3 days
(cherry picked from commit c44bf7d2e9)
dlopen_basic just tests that libthr.so can be dlopen()ed, which will
just serve as a sanity check that "libthr.so" is a thing that can be
dlopened in case we get a weird failure in dlopen_recursing.
dlopen_recursing tests a regression reported after the libsys split,
where some dlopen() may cause infinite recursion and a resulting crash.
This case is inspired by bdrewery's description of what seemed to be
causing his issue.
The corresponding fix landed in commit
968a18975a ("rtld: ignore load_filtees() calls if we already [...]")
Reviewed by: kib
(cherry picked from commit c5796f1572)
This was originally used (along with FREEBSD_AOUT) to prefer the use
of ELF in various tools instead of a.out as part of the a.out to ELF
transition in the 3.x days. The last use of it was removed from
<link.h> in commit 66422f5b7a back in
2002, but various files still #define it.
Reviewed by: kevans, imp, emaste
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D42964
(cherry picked from commit 4a3cf5f329)
This tests that with RTLD_DEEPBIND, symbols are looked up in all of the
object's needed objects before the global object.
ATF_REQUIRE_INTEQ was added after stable/13 branched, so we shim it out
here.
PR: 275393
Reviewed by: kib
Sponsored by: NetApp, Inc.
Sponsored by: Klara, Inc.
(cherry picked from commit d9c543b6b0)
These do not use __FBSDID but instead use bare char arrays.
Reviewed by: imp, emaste
Differential Revision: https://reviews.freebsd.org/D41957
(cherry picked from commit eba230afba)
The SPDX folks have obsoleted the BSD-2-Clause-NetBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.
Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix
(cherry picked from commit b61a573019)
The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.
Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix
(cherry picked from commit 4d846d260e)
Quoting from https://maskray.me/blog/2023-04-12-elf-hash-function:
The System V Application Binary Interface (generic ABI) specifies the
ELF object file format. When producing an output executable or shared
object needing a dynamic symbol table (.dynsym), a linker generates a
.hash section with type SHT_HASH to hold a symbol hash table. A DT_HASH
tag is produced to hold the address of .hash.
The function is supposed to return a value no larger than 0x0fffffff.
Unfortunately, there is a bug. When unsigned long consists of more than
32 bits, the return value may be larger than UINT32_MAX. For instance,
elf_hash((const unsigned char *)"\xff\x0f\x0f\x0f\x0f\x0f\x12") returns
0x100000002, which is clearly unintended, as the function should behave
the same way regardless of whether long represents a 32-bit integer or
a 64-bit integer.
Reviewed by: kib, Fangrui Song
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39517
(cherry picked from commit 29e3a06510)
