Commit Graph

3008 Commits

Author SHA1 Message Date
Carlos O'Donell
ac14b7ee06 elf: Sort Makefile variables.
Sort Makefile variables using scrips/sort-makefile-lines.py.

No code generation changes observed in non-test binary artifacts.
No regressions on x86_64 and i686.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2023-06-02 21:43:05 -04:00
Paul Pluzhnikov
2cbeda847b Fix a few more typos I missed in previous round -- BZ 25337 2023-06-02 23:46:32 +00:00
Florian Weimer
b376bb01fb elf: Remove spurios SHARED conditional from elf/rtld.c
elf/rtld.c is only ever built in SHARED mode.
2023-05-31 07:35:07 +02:00
Florian Weimer
d0f07f7df8 elf: Make more functions available for binding during dlclose (bug 30425)
Previously, after destructors for a DSO have been invoked, ld.so refused
to bind against that DSO in all cases.  Relax this restriction somewhat
if the referencing object is itself a DSO that is being unloaded.  This
assumes that the symbol reference is not going to be stored anywhere.

The situation in the test case can arise fairly easily with C++ and
objects that are built with different optimization levels and therefore
define different functions with vague linkage.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2023-05-30 13:25:50 +02:00
Paul Pluzhnikov
630da022cb Fix misspellings in elf/ -- BZ 25337
Applying this commit results in bit-identical libc.so.6.
The elf/ld-linux-x86-64.so.2 does change, but only in .note.gnu.build-id

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2023-05-29 23:00:12 +00:00
Joseph Myers
8754a4133e Add AT_RSEQ_* from Linux 6.3 to elf.h
Linux 6.3 adds constants AT_RSEQ_FEATURE_SIZE and AT_RSEQ_ALIGN; add
them to glibc's elf.h.  (Recall that, although elf.h is a
system-independent header, so far we've put AT_* constants there even
if Linux-specific, as discussed in bug 15794.  So rather than making
any attempt to fix that issue, the new constants are just added there
alongside the existing ones.)

Tested for x86_64.
2023-05-26 15:03:31 +00:00
Roy Eldar
d2b1af4305 elf: add test for dl-printf
This patch checks _dl_debug_vdprintf, by passing various inputs to
_dl_dprintf and comparing the output with invocations of snprintf.

Signed-off-by: Roy Eldar <royeldar0@gmail.com>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
2023-05-25 18:51:23 +02:00
Roy Eldar
dae8015273 elf: fix handling of negative numbers in dl-printf
_dl_debug_vdprintf is a bare-bones printf implementation; currently
printing a signed integer (using "%d" format specifier) behaves
incorrectly when the number is negative, as it just prints the
corresponding unsigned integer, preceeded by a minus sign.

For example, _dl_printf("%d", -1) would print '-4294967295'.

Signed-off-by: Roy Eldar <royeldar0@gmail.com>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
2023-05-25 18:50:59 +02:00
Siddhesh Poyarekar
44d4d3bdcf elf: Update comment in open_path
f55727ca53 updated open_path to use the
r_search_path_struct struct but failed to update the comment.

Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-05-25 11:15:54 -04:00
Qixing ksyx Xue
dbfc83bdca elf: Add test for locating libraries in root dir (bug 30435)
When dlopen is being called, efforts have been made to improve
future lookup performance. This includes marking a search path
as non-existent using `stat`. However, if the root directory
is given as a search path, there exists a bug which erroneously
marks it as non-existing.

The bug is reproduced under the following sequence:

  1. dlopen is called to open a shared library, with at least:
     1) a dependency 'A.so' not directly under the '/' directory
        (e.g. /lib/A.so), and
     2) another dependency 'B.so' resides in '/'.
  2. for this bug to reproduce, 'A.so' should be searched *before* 'B.so'.
  3. it first tries to find 'A.so' in /, (e.g. /A.so):
     - this will (obviously) fail,
     - since it's the first time we have seen the '/' directory,
       its 'status' is 'unknown'.
  4. `buf[buflen - namelen - 1] = '\0'` is executed:
     - it intends to remove the leaf and its final slash,
     - because of the speciality of '/', its buflen == namelen + 1,
     - it erroneously clears the entire buffer.
  6. it then calls 'stat' with the empty buffer:
     - which will result in an error.
  7. so it marks '/' as 'nonexisting', future lookups will not consider
     this path.
  8. while /B.so *does* exist, failure to look it up in the '/'
     directory leads to a 'cannot open shared object file' error.

This patch fixes the bug by preventing 'buflen', an index to put '\0',
from being set to 0, so that the root '/' is always kept.
Relative search paths are always considered as 'existing' so this
wont be affected.

Writeup by Moody Liu <mooodyhunter@outlook.com>

Suggested-by: Carlos O'Donell <carlos@redhat.com>
Signed-off-by: Qixing ksyx Xue <qixingxue@outlook.com>
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-05-25 11:10:54 -04:00
Andreas Schwab
e0189b2540 rtld: properly handle root directory in load path (bug 30435)
Don't strip the trailing slash when checking for existence of a load path
element to handle the special case of the root directory.
2023-05-25 11:47:12 +02:00
Carlos O'Donell
a08e854d00 elf: Adjust tests in Makefile.
Sort tests against updated scripts/sort-makefile-lines.py.

No changes in generated code.
No regressions on x86_64 and i686.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-05-18 12:33:44 -04:00
Carlos O'Donell
aa492359f1 elf: Reformat Makefile.
Fix list terminator whitspace.
Sort using scripts/sort-makefile-lines.py.

No code generation changes observed in binary artifacts.
No regressions on x86_64 and i686.
2023-05-16 07:17:19 -04:00
Andreas Schwab
ab5aa2ee3d dlopen: skip debugger notification for DSO loaded from sprof (bug 30258)
Avoid inconsistent state in the debugger interface.
2023-05-09 14:36:34 +02:00
Florian Weimer
bf88b47ecb Revert "riscv: Resolve symbols directly for symbols with STO_RISCV_VARIANT_CC."
This reverts commit 117e8b341c.

Reason for revert: Causes elf/tst-glibcelf and elf/tst-relro-*
to fail on all architectures.
2023-05-07 14:16:03 +02:00
Hsiangkai Wang
117e8b341c
riscv: Resolve symbols directly for symbols with STO_RISCV_VARIANT_CC.
In some cases, we do not want to go through the resolver for function
calls. For example, functions with vector arguments will use vector
registers to pass arguments. In the resolver, we do not save/restore the
vector argument registers for lazy binding efficiency. To avoid ruining
the vector arguments, functions with vector arguments will not go
through the resolver.

To achieve the goal, we will annotate the function symbols with
STO_RISCV_VARIANT_CC flag and add DT_RISCV_VARIANT_CC tag in the dynamic
section. In the first pass on PLT relocations, we do not set up to call
_dl_runtime_resolve. Instead, we resolve the functions directly.

Signed-off-by: Hsiangkai Wang <kai.wang@sifive.com>
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Link: https://inbox.sourceware.org/libc-alpha/20230314162512.35802-1-kito.cheng@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-28 07:02:42 -07:00
Indu Bhagat
2fa7fd1af7 elf.h: add PT_GNU_SFRAME
Support for SFrame format is available in Binutils 2.40.  The GNU ld merges
the input .sframe sections and creates an output .sframe section in a
segment PT_GNU_SFRAME.
2023-04-28 10:53:05 +02:00
Sergey Bugaev
533deafbdf Use O_CLOEXEC in more places (BZ #15722)
When opening a temporary file without O_CLOEXEC we risk leaking the
file descriptor if another thread calls (fork and then) exec while we
have the fd open. Fix this by consistently passing O_CLOEXEC everywhere
where we open a file for internal use (and not to return it to the user,
in which case the API defines whether or not the close-on-exec flag
shall be set on the returned fd).

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230419160207.65988-4-bugaevc@gmail.com>
2023-04-22 13:50:14 +02:00
Adhemerval Zanella Netto
33237fe83d Remove --enable-tunables configure option
And make always supported.  The configure option was added on glibc 2.25
and some features require it (such as hwcap mask, huge pages support, and
lock elisition tuning).  It also simplifies the build permutations.

Changes from v1:
 * Remove glibc.rtld.dynamic_sort changes, it is orthogonal and needs
   more discussion.
 * Cleanup more code.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-03-29 14:33:06 -03:00
Romain Geissler
bb557fff2e elf: Take into account ${sysconfdir} in elf/tst-ldconfig-p.sh
Take into account ${sysconfdir} in elf/tst-ldconfig-p.sh.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2023-03-27 16:58:08 -03:00
Romain Geissler
4b4b62191e Fix tst-glibc-hwcaps-prepend-cache with custom configure prefix value
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2023-03-27 16:58:08 -03:00
Romain Geissler
cce422a632 Fix tst-ldconfig-ld_so_conf-update with custom configure prefix value
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2023-03-27 16:58:08 -03:00
Adhemerval Zanella Netto
91fc5b9990 Remove --with-default-link configure option
Now that there is no need to use a special linker script to hardening
internal data structures, remove the --with-default-link configure
option and associated definitions.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2023-03-27 13:57:55 -03:00
Adhemerval Zanella Netto
3020f72618 libio: Remove the usage of __libc_IO_vtables
Instead of using a special ELF section along with a linker script
directive to put the IO vtables within the RELRO section, the libio
vtables are all moved to an array marked as data.relro (so linker
will place in the RELRO segment without the need of extra directives).

To avoid static linking namespace issues and including all vtable
referenced objects, all required function pointers are set to weak alias.

Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2023-03-27 13:57:55 -03:00
Adhemerval Zanella Netto
88677348b4 Move libc_freeres_ptrs and libc_subfreeres to hidden/weak functions
They are both used by __libc_freeres to free all library malloc
allocated resources to help tooling like mtrace or valgrind with
memory leak tracking.

The current scheme uses assembly markers and linker script entries
to consolidate the free routine function pointers in the RELRO segment
and to be freed buffers in BSS.

This patch changes it to use specific free functions for
libc_freeres_ptrs buffers and call the function pointer array directly
with call_function_static_weak.

It allows the removal of both the internal macros and the linker
script sections.

Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2023-03-27 13:57:55 -03:00
Andreas Schwab
152f863926 _dl_map_object_from_fd: Remove unnecessary debugger notification in error path
After commit ed3ce71f5c ("elf: Move la_activity (LA_ACT_ADD) after
_dl_add_to_namespace_list() (BZ #28062)") it is no longer necessary to
reset the debugger state in the error case, since the debugger
notification only happens after no more errors can occur.
2023-03-27 10:06:07 +02:00
Paul Pluzhnikov
1b5e65ef6a Minor: don't call _dl_debug_update (which can have side effects) inside assert 2023-03-26 00:22:30 +00:00
caiyinyu
f0d33cbdce LoongArch: Add support for ldconfig. 2023-03-13 09:20:28 +08:00
Arsen Arsenović
f7e751affb elf: Add missing dependency between resolvfail and testobj1.so
It was possible to run this test individually and have it fail because
it can't find testobj1.so.  This patch adds that dependency, to prevent
such issues.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2023-03-10 17:53:18 +01:00
Arsen Arsenović
6c7388d0b9 elf: Add -z lazy to some more tests
Some toolchains, such as that used on Gentoo Hardened, set -z now out of
the box.  This trips up a couple of tests.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2023-03-10 17:53:15 +01:00
Simon Kissane
31be941e43 gmon: improve mcount overflow handling [BZ# 27576]
When mcount overflows, no gmon.out file is generated, but no message is printed
to the user, leaving the user with no idea why, and thinking maybe there is
some bug - which is how BZ 27576 ended up being logged. Print a message to
stderr in this case so the user knows what is going on.

As a comment in sys/gmon.h acknowledges, the hardcoded MAXARCS value is too
small for some large applications, including the test case in that BZ. Rather
than increase it, add tunables to enable MINARCS and MAXARCS to be overridden
at runtime (glibc.gmon.minarcs and glibc.gmon.maxarcs). So if a user gets the
mcount overflow error, they can try increasing maxarcs (they might need to
increase minarcs too if the heuristic is wrong in their case.)

Note setting minarcs/maxarcs too large can cause monstartup to fail with an
out of memory error. If you set them large enough, it can cause an integer
overflow in calculating the buffer size. I haven't done anything to defend
against that - it would not generally be a security vulnerability, since these
tunables will be ignored in suid/sgid programs (due to the SXID_ERASE default),
and if you can set GLIBC_TUNABLES in the environment of a process, you can take
it over anyway (LD_PRELOAD, LD_LIBRARY_PATH, etc). I thought about modifying
the code of monstartup to defend against integer overflows, but doing so is
complicated, and I realise the existing code is susceptible to them even prior
to this change (e.g. try passing a pathologically large highpc argument to
monstartup), so I decided just to leave that possibility in-place.

Add a test case which demonstrates mcount overflow and the tunables.

Document the new tunables in the manual.

Signed-off-by: Simon Kissane <skissane@gmail.com>
Reviewed-by: DJ Delorie <dj@redhat.com>
2023-02-22 21:00:14 -05:00
Joan Bruguera
1b0ea8c5d8 elf: Restore ldconfig libc6 implicit soname logic [BZ #30125]
While cleaning up old libc version support, the deprecated libc4 code was
accidentally kept in `implicit_soname`, instead of the libc6 code.

This causes additional symlinks to be created by `ldconfig` for libraries
without a soname, e.g. a library `libsomething.123.456.789` without a soname
will create a `libsomething.123` -> `libsomething.123.456.789` symlink.

As the libc6 version of the `implicit_soname` code is a trivial `xstrdup`,
just inline it and remove `implicit_soname` altogether.

Some further simplification looks possible (e.g. the call to `create_links`
looks like a no-op if `soname == NULL`, other than the verbose printfs), but
logic is kept as-is for now.

Fixes: BZ #30125
Fixes: 8ee878592c ("Assume only FLAG_ELF_LIBC6 suport")
Signed-off-by: Joan Bruguera <joanbrugueram@gmail.com>

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2023-02-20 09:32:46 -03:00
Qihao Chencao
cc4d6614b5 Use uintptr_t instead of performing pointer subtraction with a null pointer
Signed-off-by: Qihao Chencao <twose@qq.com>

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2023-02-17 17:07:44 -03:00
Florian Weimer
9fd63e3537 elf: Smoke-test ldconfig -p against system /etc/ld.so.cache
The test is sufficient to detect the ldconfig bug fixed in
commit 9fe6f63638 ("elf: Fix 64 time_t
support for installed statically binaries").

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2023-02-08 18:11:04 +01:00
Wilco Dijkstra
32c7acd464 Replace rawmemchr (s, '\0') with strchr
Almost all uses of rawmemchr find the end of a string.  Since most targets use
a generic implementation, replacing it with strchr is better since that is
optimized by compilers into strlen (s) + s.  Also fix the generic rawmemchr
implementation to use a cast to unsigned char in the if statement.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2023-02-06 16:16:19 +00:00
caiyinyu
83d49a53aa LoongArch: Add new relocation types. 2023-02-03 09:37:07 +08:00
Adhemerval Zanella
7e31d16651 elf: Fix GL(dl_phdr) and GL(dl_phnum) for static builds [BZ #29864]
The 73fc4e28b9 refactor did not add the GL(dl_phdr) and
GL(dl_phnum) for static build, relying on the __ehdr_start symbol,
which is always added by the static linker, to get the correct values.

This is problematic in some ways:

  - The segment may see its in-memory size differ from its in-file
    size (or the binary may have holes).  The Linux has fixed is to
    provide concise values for both AT_PHDR and AT_PHNUM (commit
    0da1d5002745c - "fs/binfmt_elf: Fix AT_PHDR for unusual ELF files")

  - Some archs (alpha for instance) the hidden weak reference is not
    correctly pulled by the static linker and  __ehdr_start address
    end up being 0, which makes GL(dl_phdr) and GL(dl_phnum) have both
    invalid values (and triggering a segfault later on libc.so while
    accessing TLS variables).

The safer fix is to just restore the previous behavior to setup
GL(dl_phdr) and GL(dl_phnum) for static based on kernel auxv.  The
__ehdr_start fallback can also be simplified by not assuming weak
linkage (as for PIE).

The libc-static.c auxv init logic is moved to dl-support.c, since
the later is build without SHARED and then GLRO macro is defined
to access the variables directly.

The _dl_phdr is also assumed to be always non NULL, since an invalid
NULL values does not trigger TLS initialization (which is used in
various libc systems).

Checked on aarch64-linux-gnu, x86_64-linux-gnu, and i686-linux-gnu.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2023-01-12 13:54:34 -03:00
Joseph Myers
ae612c45ef Update copyright dates not handled by scripts/update-copyrights
I've updated copyright dates in glibc for 2023.  This is the patch for
the changes not generated by scripts/update-copyrights and subsequent
build / regeneration of generated files.
2023-01-06 21:45:36 +00:00
Joseph Myers
6d7e8eda9b Update copyright dates with scripts/update-copyrights 2023-01-06 21:14:39 +00:00
Florian Weimer
118816de33 libio: Convert __vswprintf_internal to buffers (bug 27857)
Always null-terminate the buffer and set E2BIG if the buffer is too
small.  This fixes bug 27857.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-12-19 18:56:55 +01:00
Florian Weimer
5365acc567 libio: Convert __obstack_vprintf_internal to buffers (bug 27124)
This fixes bug 27124 because the problematic built-in vtable is gone.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-12-19 18:56:55 +01:00
Florian Weimer
fb9bd841b8 libio: Convert __vsprintf_internal to buffers
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-12-19 18:56:55 +01:00
Florian Weimer
e88b9f0e5c stdio-common: Convert vfprintf and related functions to buffers
vfprintf is entangled with vfwprintf (of course), __printf_fp,
__printf_fphex, __vstrfmon_l_internal, and the strfrom family of
functions.  The latter use the internal snprintf functionality,
so vsnprintf is converted as well.

The simples conversion is __printf_fphex, followed by
__vstrfmon_l_internal and __printf_fp, and finally
__vfprintf_internal and __vfwprintf_internal.  __vsnprintf_internal
and strfrom* are mostly consuming the new interfaces, so they
are comparatively simple.

__printf_fp is a public symbol, so the FILE *-based interface
had to preserved.

The __printf_fp rewrite does not change the actual binary-to-decimal
conversion algorithm, and digits are still not emitted directly to
the target buffer.  However, the staging buffer now uses bytes
instead of wide characters, and one buffer copy is eliminated.

The changes are at least performance-neutral in my testing.
Floating point printing and snprintf improved measurably, so that
this Lua script

  for i=1,5000000 do
      print(i, i * math.pi)
  end

runs about 5% faster for me.  To preserve fprintf performance for
a simple "%d" format, this commit has some logic changes under
LABEL (unsigned_number) to avoid additional function calls.  There
are certainly some very easy performance improvements here: binary,
octal and hexadecimal formatting can easily avoid the temporary work
buffer (the number of digits can be computed ahead-of-time using one
of the __builtin_clz* built-ins). Decimal formatting can use a
specialized version of _itoa_word for base 10.

The existing (inconsistent) width handling between strfmon and printf
is preserved here.  __print_fp_buffer_1 would have to use
__translated_number_width to achieve ISO conformance for printf.

Test expectations in libio/tst-vtables-common.c are adjusted because
the internal staging buffer merges all virtual function calls into
one.

In general, stack buffer usage is greatly reduced, particularly for
unbuffered input streams.  __printf_fp can still use a large buffer
in binary128 mode for %g, though.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-12-19 18:56:54 +01:00
Florian Weimer
659fe9fdd1 stdio-common: Introduce buffers for implementing printf
These buffers will eventually be used instead of FILE * objects
to implement printf functions.  The multibyte buffer is struct
__printf_buffer, the wide buffer is struct __wprintf_buffer.

To enable writing type-generic code, the header files
printf_buffer-char.h and printf_buffer-wchar_t.h define the
Xprintf macro differently, enabling Xprintf (buffer) to stand
for __printf_buffer and __wprintf_buffer as appropriate.  For
common cases, macros like Xprintf_buffer are provided as a more
syntactically convenient shortcut.

Buffer-specific flush callbacks are implemented with a switch
statement instead of a function pointer, to avoid hardening issues
similar to those of libio vtables.  struct __printf_buffer_as_file
is needed to support custom printf specifiers because the public
interface for that requires passing a FILE *, which is why there
is a trapdoor back from these buffers to FILE * streams.

Since the immediate user of these interfaces knows when processing
has finished, there is no flush callback for the end of processing,
only a flush callback for the intermediate buffer flush.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-12-19 18:56:54 +01:00
Adhemerval Zanella
71e408e45d elf: Fix tst-relro-symbols.py argument passing
Current scheme only consideres the first argument for both --required
and --optional, where the idea is to append a new item.

Checked on x86_64-linux-gnu.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-12-15 16:59:13 -03:00
Adhemerval Zanella
d4facb63ff elf: Do not assume symbol order on tst-audit25{a,b}
The static linker might impose any order or internal function
position, so change the test to check if the audit prints the
symbol only once in any order.
2022-12-12 09:53:20 -03:00
Shahab Vahedi
6ae0737d43 ARC: update definitions in elf/elf.h
While porting ARCv2 to elfutils [1], it was brought up that the
necessary changes to the project's libelf/elf.h must come from
glibc, because they sync it from glibc [2].  Therefore, this patch
is to update ARC entries in elf/elf.h.

The majority of the update is about adding new definitions,
specially for the relocations.  However, there is one rename, one
deletion, and one change:

- R_ARC_JUMP_SLOT renamed to R_ARC_JMP_SLOT to match binutils.
- R_ARC_B26 removed because it is unused and deprecated.
- R_ARC_TLS_DTPOFF_S9 changed from 0x4a to the correct value 0x49.

Finally, a specific SHT class for ARC has been added to glibcelf.py.
Else, it would result in a collision:

  _register_elf_h(Sht, ranges=True,
 File "/src/glibc/scripts/glibcelf.py", line x, in _register_elf_h
   raise ValueError('duplicate value {}: {}, {}'.format(
                    ValueError: duplicate value 1879048193:
                    SHT_ARC_ATTRIBUTES, SHT_X86_64_UNWIND

[1]
https://sourceware.org/pipermail/elfutils-devel/2022q4/005530.html

[2]
https://sourceware.org/pipermail/elfutils-devel/2022q4/005548.html

No regression has been observed after applying this patch.  Below
follows the result:

UNSUPPORTED: crypt/cert
UNSUPPORTED: elf/tst-audit22
FAIL: elf/tst-audit25a
FAIL: elf/tst-audit25b
FAIL: elf/tst-bz15311
FAIL: elf/tst-bz28937
FAIL: elf/tst-dlmopen4
UNSUPPORTED: elf/tst-dlopen-self-container
UNSUPPORTED: elf/tst-dlopen-tlsmodid-container
UNSUPPORTED: elf/tst-glibc-hwcaps-prepend-cache
UNSUPPORTED: elf/tst-ldconfig-bad-aux-cache
UNSUPPORTED: elf/tst-ldconfig-ld_so_conf-update
UNSUPPORTED: elf/tst-pldd
UNSUPPORTED: elf/tst-preload-pthread-libc
XPASS: elf/tst-protected1a
XPASS: elf/tst-protected1b
FAIL: elf/tst-tls-allocation-failure-static-patched
FAIL: elf/tst-tls1
FAIL: elf/tst-tls3
FAIL: elf/tst-tlsalign-extern
UNSUPPORTED: elf/tst-valgrind-smoke
UNSUPPORTED: grp/tst-initgroups1
UNSUPPORTED: grp/tst-initgroups2
UNSUPPORTED: io/tst-getcwd-smallbuff
UNSUPPORTED: locale/tst-localedef-path-norm
FAIL: localedata/sort-test
UNSUPPORTED: localedata/tst-localedef-hardlinks
FAIL: malloc/tst-malloc-thread-fail-malloc-check
FAIL: malloc/tst-malloc_info-malloc-check
UNSUPPORTED: math/test-fesetexcept-traps
UNSUPPORTED: math/test-fexcept-traps
UNSUPPORTED: math/test-nearbyint-except
UNSUPPORTED: math/test-nearbyint-except-2
UNSUPPORTED: misc/tst-adjtimex
UNSUPPORTED: misc/tst-clock_adjtime
FAIL: misc/tst-misalign-clone
FAIL: misc/tst-misalign-clone-internal
UNSUPPORTED: misc/tst-ntp_adjtime
UNSUPPORTED: misc/tst-pkey
UNSUPPORTED: misc/tst-rseq
UNSUPPORTED: misc/tst-rseq-disable
UNSUPPORTED: misc/tst-syslog
UNSUPPORTED: misc/tst-ttyname
FAIL: nptl/test-cond-printers
FAIL: nptl/test-condattr-printers
FAIL: nptl/test-mutex-printers
FAIL: nptl/test-mutexattr-printers
FAIL: nptl/test-rwlock-printers
FAIL: nptl/test-rwlockattr-printers
UNSUPPORTED: nptl/tst-pthread-gdb-attach
UNSUPPORTED: nptl/tst-pthread-gdb-attach-static
UNSUPPORTED: nptl/tst-pthread-getattr
UNSUPPORTED: nptl/tst-rseq-nptl
UNSUPPORTED: nss/tst-nss-compat1
UNSUPPORTED: nss/tst-nss-db-endgrent
UNSUPPORTED: nss/tst-nss-db-endpwent
UNSUPPORTED: nss/tst-nss-files-hosts-long
UNSUPPORTED: nss/tst-nss-gai-actions
UNSUPPORTED: nss/tst-nss-test3
UNSUPPORTED: nss/tst-reload1
UNSUPPORTED: nss/tst-reload2
UNSUPPORTED: posix/bug-ga2
UNSUPPORTED: posix/bug-ga2-mem
FAIL: posix/globtest
UNSUPPORTED: posix/tst-vfork3
UNSUPPORTED: posix/tst-vfork3-mem
UNSUPPORTED: resolv/mtrace-tst-leaks2
UNSUPPORTED: resolv/tst-leaks2
UNSUPPORTED: resolv/tst-resolv-ai_idn
UNSUPPORTED: resolv/tst-resolv-ai_idn-latin1
UNSUPPORTED: resolv/tst-resolv-res_init
UNSUPPORTED: resolv/tst-resolv-res_init-thread
UNSUPPORTED: rt/tst-bz28213
UNSUPPORTED: rt/tst-mqueue1
UNSUPPORTED: rt/tst-mqueue10
UNSUPPORTED: rt/tst-mqueue2
UNSUPPORTED: rt/tst-mqueue3
UNSUPPORTED: rt/tst-mqueue4
UNSUPPORTED: rt/tst-mqueue5
UNSUPPORTED: rt/tst-mqueue6
UNSUPPORTED: rt/tst-mqueue8
UNSUPPORTED: rt/tst-mqueue8x
UNSUPPORTED: rt/tst-mqueue9
UNSUPPORTED: stdlib/test-bz22786
UNSUPPORTED: stdlib/tst-system
UNSUPPORTED: string/test-bcopy
UNSUPPORTED: string/test-memmove
UNSUPPORTED: string/tst-memmove-overflow
UNSUPPORTED: string/tst-strerror
UNSUPPORTED: string/tst-strsignal
UNSUPPORTED: time/tst-clock_settime
UNSUPPORTED: time/tst-settimeofday
Summary of test results:
     21 FAIL
   4184 PASS
     69 UNSUPPORTED
     16 XFAIL
      2 XPASS

Signed-off-by: Shahab Vahedi <shahab@synopsys.com>
Signed-off-by: Vineet Gupta <vineet.gupta@linux.dev>
2022-11-29 14:33:56 -08:00
Xiaoming Ni
d1d0162e50 elf/tlsdeschtab.h: Add the Malloc return value check in _dl_make_tlsdesc_dynamic()
Check the return value of malloc based on the function header comment of
 _dl_make_tlsdesc_dynamic(). If the return value fails, NULL is returned.

Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2022-11-07 13:13:07 +00:00
Florian Weimer
9cc9d61ee1 elf: Disable some subtests of ifuncmain1, ifuncmain5 for !PIE 2022-11-04 18:46:22 +01:00
Florian Weimer
1f34a23288 elf: Introduce <dl-call_tls_init_tp.h> and call_tls_init_tp (bug 29249)
This makes it more likely that the compiler can compute the strlen
argument in _startup_fatal at compile time, which is required to
avoid a dependency on strlen this early during process startup.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2022-11-03 17:28:03 +01:00
caiyinyu
fb6ee7ba81 LoongArch: Fix ABI related macros in elf.h to keep consistent with binutils[1].
[1]:
https://sourceware.org/git/?p=binutils-gdb.git;a=commitdiff;h=c4a7e6b56218e1d5a858682186b542e2eae01a4a;hp=0d94a8735055432029237612a6eb9165db1ec9dd
[2]:
Reference: https://loongson.github.io/LoongArch-Documentation/LoongArch-ELF-ABI-EN.html#_e_flags_identifies_abi_type_and_version
2022-11-03 21:02:56 +08:00
Florian Weimer
ee1ada1bdb elf: Rework exception handling in the dynamic loader [BZ #25486]
The old exception handling implementation used function interposition
to replace the dynamic loader implementation (no TLS support) with the
libc implementation (TLS support).  This results in problems if the
link order between the dynamic loader and libc is reversed (bug 25486).

The new implementation moves the entire implementation of the
exception handling functions back into the dynamic loader, using
THREAD_GETMEM and THREAD_SETMEM for thread-local data support.
These depends on Hurd support for these macros, added in commit
b65a82e4e7 ("hurd: Add THREAD_GET/SETMEM/_NC").

One small obstacle is that the exception handling facilities are used
before the TCB has been set up, so a check is needed if the TCB is
available.  If not, a regular global variable is used to store the
exception handling information.

Also rename dl-error.c to dl-catch.c, to avoid confusion with the
dlerror function.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-11-03 09:39:31 +01:00
Adhemerval Zanella
40c112ed0d elf: Remove allocate use on _dl_debug_printf
The maximum number of directives is already limited by the maximum
value of iovec, and current padding usage on _dl_map_object_from_fd
specifies a value of 16 (2 times sizeof (void *)) in hexa, which is
less than the INT_STRLEN_BOUND(void *) (20 for LP64).

This works if pointers are larger than 8 bytes, for instance 16.
In this case the maximum padding would be 32 and the IFMTSIZE would
be 40.

The resulting code does use a slightly larger static stack, the
output of -fstack-usage (for x86_64):

 * master:
   dl-printf.c:35:1:_dl_debug_vdprintf     1344    dynamic

 * patch:
   dl-printf.c:36:1:_dl_debug_vdprintf     2416    static

However, there is an improvement in code generation:

 * master
   text    data     bss     dec     hex filename
   3309       0       0    3309     ced elf/dl-printf.os

 * patch
   text    data     bss     dec     hex filename
   3151       0       0    3151     c4f elf/dl-printf.os

Checked on x86_64-linux-gnu.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2022-11-02 11:30:24 -03:00
H.J. Lu
bbff275fb1 elf: Build tst-relr-mod[34]a.so with $(LDFLAGS-rpath-ORIGIN)
When --enable-hardcoded-path-in-tests is used only with DT_RUNPATH,
elf/tst-relr3 and elf/tst-relr4 failed to run.  Their dependency
libraries, tst-relr-mod3a.so and tst-relr-mod4a.so, are failed to
load since DT_RUNPATH on executable doesn't apply to them.  Build
tst-relr-mod3a.so and tst-relr-mod4a.so with $(LDFLAGS-rpath-ORIGIN)
to add DT_RUNPATH for their dependency libraries.
Reviewed-by: Fangrui Song <maskray@google.com>
2022-10-31 09:00:26 -07:00
Szabolcs Nagy
2eeeee7636 Fix elf/tst-dlmopen-twice not to exhaust static TLS
By default glibc only allocates enough static TLS for 4 link namespaces
including the initial one. So only use 3 dlmopens in the test.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-10-28 18:43:58 +01:00
Szabolcs Nagy
6a3794ea91 Fix off-by-one OOB read in elf/tst-tls20
The int mods[nmods] array on the stack was overread by one.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-10-28 11:16:51 +01:00
Szabolcs Nagy
eef17d4d9f elf: Fix alloca size in _dl_debug_vdprintf
The alloca size did not consider the optional width parameter for
padding which could cause buffer underflow. The width is currently used
e.g. by _dl_map_object_from_fd which passes 2 * sizeof(void *) which
can be larger than the alloca buffer size on targets where
sizeof(void *) >= 2 * sizeof(unsigned long).

Even if large width is not used on existing targets it is better to fix
the formatting code to avoid surprises.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-10-28 11:16:09 +01:00
Florian Weimer
6f360366f7 elf: Introduce to _dl_call_fini
This consolidates the destructor invocations from _dl_fini and
dlclose.  Remove the micro-optimization that avoids
calling _dl_call_fini if they are no destructors (as dlclose is quite
expensive anyway).  The debug log message is now printed
unconditionally.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-10-27 11:36:44 +02:00
Florian Weimer
a65ff76c9a ld.so: Export tls_init_tp_called as __rtld_tls_init_tp_called
This allows the rest of dynamic loader to check whether the TCB
has been set up (and THREAD_GETMEM and THREAD_SETMEM will work).

Reviewed-by: Siddhesh Poyarekar <siddhesh@gotplt.org>
2022-10-27 11:36:44 +02:00
Adhemerval Zanella
891a7958a2 elf: Reinstate on DL_DEBUG_BINDINGS _dl_lookup_symbol_x
The prelink removal done by 6628c742b2 wrongly removed the debug
support.

Checked on x86_64-linux-gnu.
2022-10-26 09:47:10 -03:00
Florian Weimer
2c42257314 elf: Do not completely clear reused namespace in dlmopen (bug 29600)
The data in the _ns_debug member must be preserved, otherwise
_dl_debug_initialize enters an infinite loop.  To be conservative,
only clear the libc_map member for now, to fix bug 29528.

Fixes commit d0e357ff45
("elf: Call __libc_early_init for reused namespaces (bug 29528)"),
by reverting most of it.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2022-10-14 11:02:25 +02:00
Joseph Myers
ba0ca36132 Add NT_S390_PV_CPU_DATA from Linux 6.0 to elf.h
Add the new NT_S390_PV_CPU_DATA constant from Linux 6.0 to glibc's
elf.h.

Tested for x86_64.
2022-10-12 14:28:47 +00:00
Adhemerval Zanella
5355f9ca7b elf: Remove -fno-tree-loop-distribute-patterns usage on dl-support
Besides the option being gcc specific, this approach is still fragile
and not future proof since we do not know if this will be the only
optimization option gcc will add that transforms loops to memset
(or any libcall).

This patch adds a new header, dl-symbol-redir-ifunc.h, that can b
used to redirect the compiler generated libcalls to port the generic
memset implementation if required.

Checked on x86_64-linux-gnu and aarch64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-10-10 10:32:28 -03:00
Javier Pello
e76369ed63 elf: Simplify output of hwcap subdirectories in ld.so help
The print_hwcap_1 machinery was useful for the legacy hwcaps
subdirectories, but it is not worth the trouble now that they
are gone.

Signed-off-by: Javier Pello <devel@otheo.eu>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-10-06 07:59:48 -03:00
Javier Pello
cfbf883db3 elf: Remove hwcap and bits_hwcap fields from struct cache_entry
They were set to 0 on initialisation and never changed later after
last commit.

Signed-off-by: Javier Pello <devel@otheo.eu>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-10-06 07:59:48 -03:00
Javier Pello
4a7094119c elf: Remove hwcap parameter from add_to_cache signature
Last commit made it so that the value passed for that parameter was
always 0 at its only call site.

Signed-off-by: Javier Pello <devel@otheo.eu>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-10-06 07:59:48 -03:00
Javier Pello
b78ff5a25d elf: Remove legacy hwcaps support from ldconfig
Remove support for the legacy hwcaps subdirectories from ldconfig.

Signed-off-by: Javier Pello <devel@otheo.eu>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-10-06 07:59:48 -03:00
Javier Pello
6099908fb8 elf: Remove legacy hwcaps support from the dynamic loader
Remove support for the legacy hwcaps subdirectories from the dynamic
loader.

Signed-off-by: Javier Pello <devel@otheo.eu>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-10-06 07:59:48 -03:00
Adhemerval Zanella Netto
de477abcaa Use '%z' instead of '%Z' on printf functions
The Z modifier is a nonstandard synonymn for z (that predates z
itself) and compiler might issue an warning for in invalid
conversion specifier.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-09-22 08:48:04 -03:00
Florian Weimer
340097d0b5 elf: Extract glibcelf constants from <elf.h>
The need to maintain elf/elf.h and scripts/glibcelf.py in parallel
results in a backporting hazard: they need to be kept in sync to
avoid elf/tst-glibcelf consistency check failures.  glibcelf (unlike
tst-glibcelf) does not use the C implementation to extract constants.
This applies the additional glibcpp syntax checks to <elf.h>.

This  changereplaces the types derived from Python enum types with
custom types _TypedConstant, _IntConstant, and _FlagConstant.  These
types have fewer safeguards, but this also allows incremental
construction and greater flexibility for grouping constants among
the types.  Architectures-specific named constants are now added
as members into their superclasses (but value-based lookup is
still restricted to generic constants only).

Consequently, check_duplicates in elf/tst-glibcelf has been adjusted
to accept differently-named constants of the same value if their
subtypes are distinct.  The ordering check for named constants
has been dropped because they are no longer strictly ordered.

Further test adjustments: Some of the type names are different.
The new types do not support iteration (because it is unclear
whether iteration should cover the all named values (including
architecture-specific constants), or only the generic named values),
so elf/tst-glibcelf now uses by_name explicit (to get all constants).
PF_HP_SBP and PF_PARISC_SBP are now of distinct types (PfHP and
PfPARISC), so they are how both present on the Python side.  EM_NUM
and PT_NUM are filtered (which was an oversight in the old
conversion).

The new version of glibcelf should also be compatible with earlier
Python versions because it no longer depends on the enum module and its
advanced features.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-09-22 12:10:41 +02:00
Adhemerval Zanella
fd36873ff9 elf: Use C11 atomics on _dl_mcount
All atomic operation are counters, so relaxed MO should be suffice.

Checked on x86_64-linux-gnu.
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
2022-09-21 10:57:47 -03:00
Florian Weimer
1df71d32fe elf: Implement force_first handling in _dl_sort_maps_dfs (bug 28937)
The implementation in _dl_close_worker requires that the first
element of l_initfini is always this very map (“We are always the
zeroth entry, and since we don't include ourselves in the
dependency analysis start at 1.”).  Rather than fixing that
assumption, this commit adds an implementation of the force_first
argument to the new dependency sorting algorithm.  This also means
that the directly dlopen'ed shared object is always initialized last,
which is the least surprising behavior in the presence of cycles.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-09-20 11:00:42 +02:00
Sergei Trofimovich
2d7ed98add Makerules: fix MAKEFLAGS assignment for upcoming make-4.4 [BZ# 29564]
make-4.4 will add long flags to MAKEFLAGS variable:

    * WARNING: Backward-incompatibility!
      Previously only simple (one-letter) options were added to the MAKEFLAGS
      variable that was visible while parsing makefiles.  Now, all options
      are available in MAKEFLAGS.

This causes locale builds to fail when long options are used:

    $ make --shuffle
    ...
    make  -C localedata install-locales
    make: invalid shuffle mode: '1662724426r'

The change fixes it by passing eash option via whitespace and dashes.
That way option is appended to both single-word form and whitespace
separated form.

While at it fixed --silent mode detection in $(MAKEFLAGS) by filtering
out --long-options. Otherwise options like --shuffle flag enable silent
mode unintentionally. $(silent-make) variable consolidates the checks.

Resolves: BZ# 29564

CC: Paul Smith <psmith@gnu.org>
CC: Siddhesh Poyarekar <siddhesh@gotplt.org>
Signed-off-by: Sergei Trofimovich <slyich@gmail.com>
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-09-13 13:45:32 -04:00
Javier Pello
a23820f605 elf: Fix hwcaps string size overestimation
Commit dad90d5282 added glibc-hwcaps
support for LD_LIBRARY_PATH and, for this, it adjusted the total
string size required in _dl_important_hwcaps. However, in doing so
it inadvertently altered the calculation of the size required for
the power set strings, as the computation of the power set string
size depended on the first value assigned to the total variable,
which is later shifted, resulting in overallocation of string
space. Fix this now by using a different variable to hold the
string size required for glibc-hwcaps.

Signed-off-by: Javier Pello <devel@otheo.eu>
2022-09-08 12:12:35 +02:00
Florian Weimer
dbb75513f5 elf: Rename _dl_sort_maps parameter from skip to force_first
The new implementation will not be able to skip an arbitrary number
of objects.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-09-06 07:38:33 +02:00
Florian Weimer
29eb796119 elf.h: Remove duplicate definition of VER_FLG_WEAK
This did not cause a warning before because the token sequence for
the two definitions was identical.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-09-05 15:02:09 +02:00
Adhemerval Zanella
1e903124ce elf: Restore how vDSO dependency is printed with LD_TRACE_LOADED_OBJECTS (BZ #29539)
The d7703d3176 changed how vDSO like
dependencies are printed, instead of just the name and address it
follows other libraries mode and prints 'name => path'.

Unfortunately, this broke some ldd consumer that uses the output to
filter out the program's dependencies.  For instance CMake
bundleutilities module [1], where GetPrequirite uses the regex to filter
out 'name => path' [2].

This patch restore the previous way to print just the name and the
mapping address.

Checked on x86_64-linux-gnu.

[1] https://github.com/Kitware/CMake/tree/master/Tests/BundleUtilities
[2] https://github.com/Kitware/CMake/blob/master/Modules/GetPrerequisites.cmake#L733

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-08-31 09:08:33 -03:00
Florian Weimer
d0e357ff45 elf: Call __libc_early_init for reused namespaces (bug 29528)
libc_map is never reset to NULL, neither during dlclose nor on a
dlopen call which reuses the namespace structure.  As a result, if a
namespace is reused, its libc is not initialized properly.  The most
visible result is a crash in the <ctype.h> functions.

To prevent similar bugs on namespace reuse from surfacing,
unconditionally initialize the chosen namespace to zero using memset.
2022-08-26 21:15:43 +02:00
Florian Weimer
89baed0b93 Revert "Detect ld.so and libc.so version inconsistency during startup"
This reverts commit 6f85dbf102.

Once this change hits the release branches, it will require relinking
of all statically linked applications before static dlopen works
again, for the majority of updates on release branches: The NEWS file
is regularly updated with bug references, so the __libc_early_init
suffix changes, and static dlopen cannot find the function anymore.

While this ABI check is still technically correct (we do require
rebuilding & relinking after glibc updates to keep static dlopen
working), it is too drastic for stable release branches.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-08-25 18:46:43 +02:00
Joseph Myers
025a8cce63 Add NT_LOONGARCH_* from Linux 5.19 to elf.h
Add the new NT_LOONGARCH_* constants from Linux 5.19 to glibc's elf.h.

Tested for x86_64.
2022-08-24 18:19:13 +00:00
Florian Weimer
6f85dbf102 Detect ld.so and libc.so version inconsistency during startup
The files NEWS, include/link.h, and sysdeps/generic/ldsodefs.h
contribute to the version fingerprint used for detection.  The
fingerprint can be further refined using the --with-extra-version-id
configure argument.

_dl_call_libc_early_init is replaced with _dl_lookup_libc_early_init.
The new function is used store a pointer to libc.so's
__libc_early_init function in the libc_map_early_init member of the
ld.so namespace structure.  This function pointer can then be called
directly, so the separate invocation function is no longer needed.

The versioned symbol lookup needs the symbol versioning data
structures, so the initialization of libc_map and libc_map_early_init
is now done from _dl_check_map_versions, after this information
becomes available.  (_dl_map_object_from_fd does not set this up
in time, so the initialization code had to be moved from there.)
This means that the separate initialization code can be removed from
dl_main because _dl_check_map_versions covers all maps, including
the initial executable loaded by the kernel.  The lookup still happens
before relocation and the invocation of IFUNC resolvers, so IFUNC
resolvers are protected from ABI mismatch.

The __libc_early_init function pointer is not protected because
so little code runs between the pointer write and the invocation
(only dynamic linker code and IFUNC resolvers).

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-08-24 17:35:57 +02:00
Florian Weimer
bd13cb19f5 scripts/glibcelf.py: Add hashing support
ELF and GNU hashes can now be computed using the elf_hash and
gnu_hash functions.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2022-08-23 19:33:38 +02:00
Florian Weimer
dd2315a866 elf: Run tst-audit-tlsdesc, tst-audit-tlsdesc-dlopen everywhere
The test is valid for all TLS models, but we want to make a reasonable
effort to test the GNU2 model specifically.  For example, aarch64
defaults to GNU2, but does not have -mtls-dialect=gnu2, and the test
was not run there.

Suggested-by: Martin Coufal <mcoufal@redhat.com>
2022-08-16 12:00:03 +02:00
Fangrui Song
61d2066c19 elf.h: Add ELFCOMPRESS_ZSTD
From the approved generic ABI proposal
https://groups.google.com/g/generic-abi/c/satyPkuMisk
("Add new ch_type value: ELFCOMPRESS_ZSTD").

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-08-10 21:46:09 -07:00
Noah Goldstein
483cfe1a6a elf: Replace strcpy call with memcpy [BZ #29454]
GCC normally does this optimization for us in
strlen_pass::handle_builtin_strcpy but only for optimized
build. To avoid needing to include strcpy.S in the rtld build to
support the debug build, just do the optimization by hand.
2022-08-09 17:00:03 +08:00
Florian Weimer
6c93af6b45 malloc: Correct the documentation of the top_pad default
DEFAULT_TOP_PAD is defined as 131072 in
sysdeps/generic/malloc-machine.h.
2022-08-04 17:20:48 +02:00
Lucas A. M. Magalhaes
8ee878592c Assume only FLAG_ELF_LIBC6 suport
The older libc versions are obsolete for over twenty years now.
This patch removes the special flags for libc5 and libc4 and assumes
that all libraries cached are libc6 compatible and use FLAG_ELF_LIBC6.

Checked with a build for all affected architectures.

Co-authored-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-08-04 09:09:48 -03:00
Florian Weimer
9001cb1102 assert: Do not use stderr in libc-internal assert
Redirect internal assertion failures to __libc_assert_fail, based on
based on __libc_message, which writes directly to STDERR_FILENO
and calls abort.  Also disable message translation and reword the
error message slightly (adjusting stdlib/tst-bz20544 accordingly).

As a result of these changes, malloc no longer needs its own
redefinition of __assert_fail.

__libc_assert_fail needs to be stubbed out during rtld dependency
analysis because the rtld rebuilds turn __libc_assert_fail into
__assert_fail, which is unconditionally provided by elf/dl-minimal.c.

This change is not possible for the public assert macro and its
__assert_fail function because POSIX requires that the diagnostic
is written to stderr.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-08-03 11:43:04 +02:00
Andreas Schwab
521d540562 Don't use unsupported format string in ld.so (bug 29427)
The dynamic loader does not support printf format strings that contain a
literal field width or precision, they have to be specified indirectly.
2022-08-02 10:24:21 +02:00
caiyinyu
2d83247d90 LoongArch: Add relocations and ELF flags to elf.h and scripts/glibcelf.py 2022-07-26 12:35:12 -03:00
Adhemerval Zanella
c353689e49 elf: Fix wrong fscanf usage on tst-pldd
The fix done b2cd93fce6 does not really
work since macro strification does not expand the sizeof nor the
arithmetic operation.

Checked on x86_64-linux-gnu.
2022-07-15 10:07:55 -03:00
Florian Weimer
2a5b4f7a71 elf: Rename tst-audit26 to tst-audit28
tst-audit26 and tst-audit27 are already used by aarch64.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2022-07-08 14:35:37 +02:00
Florian Weimer
a9f9ee2381 elf: Fix direction of NODELETE log messages during symbol lookup
NODELETE status is propagated from the referencing object to the
referenced object, not the other way round.  The code is correct, only
the log message has the wrong direction.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-07-05 14:40:38 +02:00
Florian Weimer
c1ada668a3 elf: Fix -DNDEBUG warning in _dl_start_args_adjust
This is another blocker for building glibc with the default
-Werror setting and -DNDEBUG.
2022-06-28 10:40:16 +02:00
Yang Yanchao
5e89ed42fd elf: Fix compile error with -Werror and -DNDEBUG
Using -Werror and -DNDEBUG at the same time will trigger the
following compiler error:

cache.c: In function 'save_cache':
cache.c:758:15: error: unused variable 'old_offset' [-Werror=unused-variable]
  758 |       off64_t old_offset = lseek64 (fd, extension_offset, SEEK_SET);
      |               ^~~~~~~~~~

-DNDEBUG disables the assertion, making old_offset unused.
Use __attribute__ ((unused)) to disable this warning.
2022-06-28 10:28:48 +02:00
Adhemerval Zanella
baf2a265c7 misc: Optimize internal usage of __libc_single_threaded
By adding an internal alias to avoid the GOT indirection.
On some architecture, __libc_single_thread may be accessed through
copy relocations and thus it requires to update also the copies
default copy.

This is done by adding a new internal macro,
libc_hidden_data_{proto,def}, which has an addition argument that
specifies the alias name (instead of default __GI_ one).

Checked on x86_64-linux-gnu and i686-linux-gnu.

Reviewed-by: Fangrui Song <maskray@google.com>
2022-06-24 17:45:58 -03:00
H.J. Lu
33ead02758 elf: Silence GCC 11/12 false positive warning
Silence GCC 11/12 false positive warning with -mavx512f on dl-load.c:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106008

$ gcc -O2 -fPIC -march=x86-64 -mavx512f -S -Wall ...
dl-load.c: In function ‘_dl_map_object_from_fd.constprop’:
dl-load.c:1158:30: warning: ‘(((char *)loadcmds.113_68 + _933 + 16))[329406144173384849].mapend’ may be used uninitialized [-Wmaybe-uninitialized]
2022-06-17 15:18:10 -07:00
Fangrui Song
de38b2a343 elf: Remove ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA
If an executable has copy relocations for extern protected data, that
can only work if the library containing the definition is built with
assumptions (a) the compiler emits GOT-generating relocations (b) the
linker produces R_*_GLOB_DAT instead of R_*_RELATIVE.  Otherwise the
library uses its own definition directly and the executable accesses a
stale copy.  Note: the GOT relocations defeat the purpose of protected
visibility as an optimization, but allow rtld to make the executable and
library use the same copy when copy relocations are present, but it
turns out this never worked perfectly.

ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA has strange semantics when both
a.so and b.so define protected var and the executable copy relocates
var: b.so accesses its own copy even with GLOB_DAT.  The behavior change
is from commit 62da1e3b00 (x86) and then
copied to nios2 (ae5eae7cfc) and arc
(0e7d930c4c).

Without ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA, b.so accesses the copy
relocated data like a.so.

There is now a warning for copy relocation on protected symbol since
commit 7374c02b68.  It's extremely
unlikely anyone relies on the ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA
behavior, so let's remove it: this removes a check in the symbol lookup
code.
2022-06-15 11:29:55 -07:00
Andreas Schwab
c2f39be490 elf: add missing newlines in lateglobal test 2022-06-08 15:28:41 +02:00
Joseph Myers
603e5c8ba7 Add PT_AARCH64_MEMTAG_MTE from Linux 5.18 to elf.h
Linux 5.18 defines a new AArch64 ELF segment type
PT_AARCH64_MEMTAG_MTE; add it to elf.h.

Tested with build-many-glibcs.py for aarch64-linux-gnu.
2022-06-06 14:45:34 +00:00
Sam James
7df596a58c grep: egrep -> grep -E, fgrep -> grep -F
Newer versions of GNU grep (after grep 3.7, not inclusive) will warn on
'egrep' and 'fgrep' invocations.

Convert usages within the tree to their expanded non-aliased counterparts
to avoid irritating warnings during ./configure and the test suite.

Signed-off-by: Sam James <sam@gentoo.org>
Reviewed-by: Fangrui Song <maskray@google.com>
2022-06-05 12:09:02 -07:00
Carlos O'Donell
48f4b30780 elf: Add #include <errno.h> for use of E* constants.
In __strerror_r we use errno constants and must include errno.h.

Tested on x86_64 and i686 without regression.
2022-06-02 15:20:36 -04:00
Carlos O'Donell
62c888b337 elf: Add #include <sys/param.h> for MAX usage.
In _dl_audit_pltenter we use MAX and so need to include param.h.

Tested on x86_64 and i686 without regression.
2022-06-02 15:20:36 -04:00
Adhemerval Zanella
81e7fdd7cc elf: Remove _dl_skip_args
Now that no architecture uses it anymore.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-05-30 16:33:54 -03:00
Fangrui Song
efa7936e4c dlsym: Make RTLD_NEXT prefer default version definition [BZ #14932]
When the first object providing foo defines both foo@v1 and foo@@v2,
dlsym(RTLD_NEXT, "foo") returns foo@v1 while dlsym(RTLD_DEFAULT, "foo")
returns foo@@v2.  The issue is that RTLD_DEFAULT uses the
DL_LOOKUP_RETURN_NEWEST flag while RTLD_NEXT doesn't.  Fix the RTLD_NEXT
branch to use DL_LOOKUP_RETURN_NEWEST.

Note: the new behavior matches FreeBSD rtld.  Future sanitizers will not
need to add versioned interceptors like https://reviews.llvm.org/D96348

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-27 12:34:49 -07:00
Fangrui Song
36c1dbaedd elf/dl-reloc.c: Copyright The GNU Toolchain Authors
by following 3.5. Update copyright information
on https://sourceware.org/glibc/wiki/Contribution%20checklist .
The change is advised by Carlos O'Donell.

Note: commit a8b11bd1f8 missed Signed-off-by tag
from Nicholas Guriev <nicholas@guriev.su>.
2022-05-23 19:16:05 -07:00
Nicholas Guriev
a8b11bd1f8 elf: Rewrite long RESOLVE_MAP macro to an always_inline static function
An __always_inline static function is better to find where exactly a
crash happens, so one can step into the function with GDB.

Reviewed-by: Fangrui Song <maskray@google.com>
2022-05-23 12:06:44 -07:00
Noah Goldstein
9a421348cd elf: Optimize _dl_new_hash in dl-new-hash.h
Unroll slightly and enforce good instruction scheduling. This improves
performance on out-of-order machines. The unrolling allows for
pipelined multiplies.

As well, as an optional sysdep, reorder the operations and prevent
reassosiation for better scheduling and higher ILP. This commit
only adds the barrier for x86, although it should be either no
change or a win for any architecture.

Unrolling further started to induce slowdowns for sizes [0, 4]
but can help the loop so if larger sizes are the target further
unrolling can be beneficial.

Results for _dl_new_hash
Benchmarked on Tigerlake: 11th Gen Intel(R) Core(TM) i7-1165G7 @ 2.80GHz

Time as Geometric Mean of N=30 runs
Geometric of all benchmark New / Old: 0.674
  type, length, New Time, Old Time, New Time / Old Time
 fixed,      0,    2.865,     2.72,               1.053
 fixed,      1,    3.567,    2.489,               1.433
 fixed,      2,    2.577,    3.649,               0.706
 fixed,      3,    3.644,    5.983,               0.609
 fixed,      4,    4.211,    6.833,               0.616
 fixed,      5,    4.741,    9.372,               0.506
 fixed,      6,    5.415,    9.561,               0.566
 fixed,      7,    6.649,   10.789,               0.616
 fixed,      8,    8.081,   11.808,               0.684
 fixed,      9,    8.427,   12.935,               0.651
 fixed,     10,    8.673,   14.134,               0.614
 fixed,     11,    10.69,   15.408,               0.694
 fixed,     12,   10.789,   16.982,               0.635
 fixed,     13,   12.169,   18.411,               0.661
 fixed,     14,   12.659,   19.914,               0.636
 fixed,     15,   13.526,   21.541,               0.628
 fixed,     16,   14.211,   23.088,               0.616
 fixed,     32,   29.412,   52.722,               0.558
 fixed,     64,    65.41,  142.351,               0.459
 fixed,    128,  138.505,  295.625,               0.469
 fixed,    256,  291.707,  601.983,               0.485
random,      2,   12.698,   12.849,               0.988
random,      4,   16.065,   15.857,               1.013
random,      8,   19.564,   21.105,               0.927
random,     16,   23.919,   26.823,               0.892
random,     32,   31.987,   39.591,               0.808
random,     64,   49.282,   71.487,               0.689
random,    128,    82.23,  145.364,               0.566
random,    256,  152.209,  298.434,                0.51

Co-authored-by: Alexander Monakov <amonakov@ispras.ru>
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-05-23 10:38:40 -05:00
Noah Goldstein
6fd435485f elf: Add tests for the dl hash funcs (_dl_new_hash and _dl_elf_hash)
If we want to further optimize the functions tests are needed.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-05-23 10:38:40 -05:00
Noah Goldstein
c4bd509d47 elf: Refactor dl_new_hash so it can be tested / benchmarked
No change to the code other than moving the function to
dl-new-hash.h. Changed name so its now in the reserved namespace.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-05-23 10:38:40 -05:00
H.J. Lu
2d5ec6692f Enable DT_RELR in glibc shared libraries and PIEs automatically
Enable DT_RELR in glibc shared libraries and position independent
executables (PIE) automatically if linker supports -z pack-relative-relocs.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-05-18 13:04:13 -07:00
Szabolcs Nagy
86147bbeec rtld: Remove DL_ARGV_NOT_RELRO and make _dl_skip_args const
_dl_skip_args is always 0, so the target specific code that modifies
argv after relro protection is applied is no longer used.

After the patch relro protection is applied to _dl_argv consistently
on all targets.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2022-05-17 10:14:03 +01:00
Szabolcs Nagy
ad43cac44a rtld: Use generic argv adjustment in ld.so [BZ #23293]
When an executable is invoked as

  ./ld.so [ld.so-args] ./exe [exe-args]

then the argv is adujusted in ld.so before calling the entry point of
the executable so ld.so args are not visible to it.  On most targets
this requires moving argv, env and auxv on the stack to ensure correct
stack alignment at the entry point.  This had several issues:

- The code for this adjustment on the stack is written in asm as part
  of the target specific ld.so _start code which is hard to maintain.

- The adjustment is done after _dl_start returns, where it's too late
  to update GLRO(dl_auxv), as it is already readonly, so it points to
  memory that was clobbered by the adjustment. This is bug 23293.

- _environ is also wrong in ld.so after the adjustment, but it is
  likely not used after _dl_start returns so this is not user visible.

- _dl_argv was updated, but for this it was moved out of relro, which
  changes security properties across targets unnecessarily.

This patch introduces a generic _dl_start_args_adjust function that
handles the argument adjustments after ld.so processed its own args
and before relro protection is applied.

The same algorithm is used on all targets, _dl_skip_args is now 0, so
existing target specific adjustment code is no longer used.  The bug
affects aarch64, alpha, arc, arm, csky, ia64, nios2, s390-32 and sparc,
other targets don't need the change in principle, only for consistency.

The GNU Hurd start code relied on _dl_skip_args after dl_main returned,
now it checks directly if args were adjusted and fixes the Hurd startup
data accordingly.

Follow up patches can remove _dl_skip_args and DL_ARGV_NOT_RELRO.

Tested on aarch64-linux-gnu and cross tested on i686-gnu.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-17 10:14:03 +01:00
Adhemerval Zanella
d2db60d8d8 Remove dl-librecon.h header.
The Linux version used by i686 and m68k provide three overrrides for
generic code:

  1. DISTINGUISH_LIB_VERSIONS to print additional information when
     libc5 is used by a dependency.

  2. EXTRA_LD_ENVVARS to that enabled LD_LIBRARY_VERSION environment
     variable.

  3. EXTRA_UNSECURE_ENVVARS to add two environment variables related
     to aout support.

None are really requires, it has some decades since libc5 or aout
suppported was removed and Linux even remove support for aout files.
The LD_LIBRARY_VERSION is also dead code, dl_correct_cache_id is not
used anywhere.

Checked on x86_64-linux-gnu and i686-linux-gnu.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-05-16 15:03:49 -03:00
Adhemerval Zanella
c628c22963 elf: Remove ldconfig kernel version check
Now that it was removed on libc.so.
2022-05-16 15:03:49 -03:00
Adhemerval Zanella
b46d250656 Remove kernel version check
The kernel version check is used to avoid glibc to run on older
kernels where some syscall are not available and fallback code are
not enabled to handle graciously fail.  However, it does not prevent
if the kernel does not correctly advertise its version through
vDSO note, uname or procfs.

Also kernel version checks are sometime not desirable by users,
where they want to deploy on different system with different kernel
version knowing the minimum set of syscall is always presented on
such systems.

The kernel version check has been removed along with the
LD_ASSUME_KERNEL environment variable.  The minimum kernel used to
built glibc is still provided through NT_GNU_ABI_TAG ELF note and
also printed when libc.so is issued.

Checked on x86_64-linux-gnu.
2022-05-16 15:03:49 -03:00
Florian Weimer
f787e138aa csu: Implement and use _dl_early_allocate during static startup
This implements mmap fallback for a brk failure during TLS
allocation.

scripts/tls-elf-edit.py is updated to support the new patching method.
The script no longer requires that in the input object is of ET_DYN
type.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-16 18:42:03 +02:00
Andreas Schwab
0b6c675073 Update RISC-V specific ELF definitions
The definitions are taken from the 1.0-rc2 version of the ELF psABI.
2022-05-16 15:51:57 +02:00
Fangrui Song
8e28aa3a51 elf: Remove fallback to the start of DT_STRTAB for dladdr
When neither DT_HASH nor DT_GNU_HASH is present, the code scans
[DT_SYMTAB, DT_STRTAB). However, there is no guarantee that .dynstr
immediately follows .dynsym (e.g. lld typically places .gnu.version
after .dynsym).

In the absence of a hash table, symbol lookup will always fail
(map->l_nbuckets == 0 in dl-lookup.c) as if the object has no symbol, so
it seems fair for dladdr to do the same.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-05-02 09:06:39 -07:00
Alan Modra
6f043e0ee7 Use __ehdr_start rather than _begin in _dl_start_final
__ehdr_start is already used in rltld.c:dl_main, and can serve the
same purpose as _begin.  Besides tidying the code, using linker
defined section relative symbols rather than "-defsym _begin=0" better
reflects the intent of _dl_start_final use of _begin, which is to
refer to the load address of ld.so rather than absolute address zero.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-04-28 08:50:11 +09:30
Adhemerval Zanella
3a0588ae48 elf: Fix DFS sorting algorithm for LD_TRACE_LOADED_OBJECTS with missing libraries (BZ #28868)
On _dl_map_object the underlying file is not opened in trace mode
(in other cases where the underlying file can't be opened,
_dl_map_object  quits with an error).  If there any missing libraries
being processed, they will not be considered on final nlist size
passed on _dl_sort_maps later in the function.  And it is then used by
_dl_sort_maps_dfs on the stack allocated working maps:

222   /* Array to hold RPO sorting results, before we copy back to  maps[].  */
223   struct link_map *rpo[nmaps];
224
225   /* The 'head' position during each DFS iteration. Note that we start at
226      one past the last element due to first-decrement-then-store (see the
227      bottom of above dfs_traversal() routine).  */
228   struct link_map **rpo_head = &rpo[nmaps];

However while transversing the 'l_initfini' on dfs_traversal it will
still consider the l_faked maps and thus update rpo more times than the
allocated working 'rpo', overflowing the stack object.

As suggested in bugzilla, one option would be to avoid sorting the maps
for trace mode.  However I think ignoring l_faked object does make
sense (there is one less constraint to call the sorting function), it
allows a slight less stack usage for trace, and it is slight simpler
solution.

The tests does trigger the stack overflow, however I tried to make
it more generic to check different scenarios or missing objects.

Checked on x86_64-linux-gnu.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-04-27 08:36:09 -03:00
H.J. Lu
4ada564f35 elf: Add more DT_RELR tests
Verify that:

1. A DT_RELR shared library without DT_NEEDED works.
2. A DT_RELR shared library without DT_VERNEED works.
3. A DT_RELR shared library without libc.so on DT_NEEDED works.
2022-04-26 10:16:11 -07:00
H.J. Lu
60196d2ef2 elf: Properly handle zero DT_RELA/DT_REL values
With DT_RELR, there may be no relocations in DT_RELA/DT_REL and their
entry values are zero.  Don't relocate DT_RELA/DT_REL and update the
combined relocation start address if their entry values are zero.
2022-04-26 10:16:11 -07:00
Fangrui Song
e895cff59a elf: Support DT_RELR relative relocation format [BZ #27924]
PIE and shared objects usually have many relative relocations. In
2017/2018, SHT_RELR/DT_RELR was proposed on
https://groups.google.com/g/generic-abi/c/bX460iggiKg/m/GxjM0L-PBAAJ
("Proposal for a new section type SHT_RELR") and is a pre-standard. RELR
usually takes 3% or smaller space than R_*_RELATIVE relocations. The
virtual memory size of a mostly statically linked PIE is typically 5~10%
smaller.

---

Notes I will not include in the submitted commit:

Available on https://sourceware.org/git/?p=glibc.git;a=shortlog;h=refs/heads/maskray/relr

"pre-standard": even Solaris folks are happy with the refined generic-abi
proposal. Cary Coutant will apply the change
https://sourceware.org/pipermail/libc-alpha/2021-October/131781.html

This patch is simpler than Chrome OS's glibc patch and makes ELF_DYNAMIC_DO_RELR
available to all ports. I don't think the current glibc implementation
supports ia64 in an ELFCLASS32 container. That said, the style I used is
works with an ELFCLASS32 container for 64-bit machine if ElfW(Addr) is
64-bit.

* Chrome OS folks have carried a local patch since 2018 (latest version:
  https://chromium.googlesource.com/chromiumos/overlays/chromiumos-overlay/+/refs/heads/main/sys-libs/glibc/files/local/glibc-2.32).
  I.e. this feature has been battle tested.
* Android bionic supports 2018 and switched to DT_RELR==36 in 2020.
* The Linux kernel has supported CONFIG_RELR since 2019-08
  (https://git.kernel.org/linus/5cf896fb6be3effd9aea455b22213e27be8bdb1d).
* A musl patch (by me) exists but is not applied:
  https://www.openwall.com/lists/musl/2019/03/06/3
* rtld-elf from FreeBSD 14 will support DT_RELR.

I believe upstream glibc should support DT_RELR to benefit all Linux
distributions. I filed some feature requests to get their attention:

* Gentoo: https://bugs.gentoo.org/818376
* Arch Linux: https://bugs.archlinux.org/task/72433
* Debian https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=996598
* Fedora https://bugzilla.redhat.com/show_bug.cgi?id=2014699

As of linker support (to the best of my knowledge):

* LLD support DT_RELR.
* https://chromium.googlesource.com/chromiumos/overlays/chromiumos-overlay/+/refs/heads/main/sys-devel/binutils/files/
  has a gold patch.
* GNU ld feature request https://sourceware.org/bugzilla/show_bug.cgi?id=27923

Changes from the original patch:

1. Check the linker option, -z pack-relative-relocs, which add a
GLIBC_ABI_DT_RELR symbol version dependency on the shared C library if
it provides a GLIBC_2.XX symbol version.
2. Change make variale to have-dt-relr.
3. Rename tst-relr-no-pie to tst-relr-pie for --disable-default-pie.
4. Use TEST_VERIFY in tst-relr.c.
5. Add the check-tst-relr-pie.out test to check for linker generated
libc.so version dependency on GLIBC_ABI_DT_RELR.
6. Move ELF_DYNAMIC_DO_RELR before ELF_DYNAMIC_DO_REL.
2022-04-26 10:16:11 -07:00
H.J. Lu
57292f5741 Add GLIBC_ABI_DT_RELR for DT_RELR support
The EI_ABIVERSION field of the ELF header in executables and shared
libraries can be bumped to indicate the minimum ABI requirement on the
dynamic linker.  However, EI_ABIVERSION in executables isn't checked by
the Linux kernel ELF loader nor the existing dynamic linker.  Executables
will crash mysteriously if the dynamic linker doesn't support the ABI
features required by the EI_ABIVERSION field.  The dynamic linker should
be changed to check EI_ABIVERSION in executables.

Add a glibc version, GLIBC_ABI_DT_RELR, to indicate DT_RELR support so
that the existing dynamic linkers will issue an error on executables with
GLIBC_ABI_DT_RELR dependency.  When there is a DT_VERNEED entry with
libc.so on DT_NEEDED, issue an error if there is a DT_RELR entry without
GLIBC_ABI_DT_RELR dependency.

Support __placeholder_only_for_empty_version_map as the placeholder symbol
used only for empty version map to generate GLIBC_ABI_DT_RELR without any
symbols.
2022-04-26 10:16:11 -07:00
H.J. Lu
4610b24f5e elf: Define DT_RELR related macros and types 2022-04-26 10:16:11 -07:00
Fangrui Song
098a657fe4 elf: Replace PI_STATIC_AND_HIDDEN with opposite HIDDEN_VAR_NEEDS_DYNAMIC_RELOC
PI_STATIC_AND_HIDDEN indicates whether accesses to internal linkage
variables and hidden visibility variables in a shared object (ld.so)
need dynamic relocations (usually R_*_RELATIVE). PI (position
independent) in the macro name is a misnomer: a code sequence using GOT
is typically position-independent as well, but using dynamic relocations
does not meet the requirement.

Not defining PI_STATIC_AND_HIDDEN is legacy and we expect that all new
ports will define PI_STATIC_AND_HIDDEN. Current ports defining
PI_STATIC_AND_HIDDEN are more than the opposite. Change the configure
default.

No functional change.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-04-26 09:26:22 -07:00
Florian Weimer
8dcb6d0af0 dlfcn: Do not use rtld_active () to determine ld.so state (bug 29078)
When audit modules are loaded, ld.so initialization is not yet
complete, and rtld_active () returns false even though ld.so is
mostly working.  Instead, the static dlopen hook is used, but that
does not work at all because this is not a static dlopen situation.

Commit 466c1ea15f ("dlfcn: Rework
static dlopen hooks") moved the hook pointer into _rtld_global_ro,
which means that separate protection is not needed anymore and the
hook pointer can be checked directly.

The guard for disabling libio vtable hardening in _IO_vtable_check
should stay for now.

Fixes commit 8e1472d2c1 ("ld.so:
Examine GLRO to detect inactive loader [BZ #20204]").

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-04-26 14:24:36 +02:00
Fangrui Song
1305edd42c elf: Move post-relocation code of _dl_start into _dl_start_final
On non-PI_STATIC_AND_HIDDEN architectures, getting the address of
_rtld_local_ro (for GLRO (dl_final_object)) goes through a GOT entry.
The GOT load may be reordered before self relocation, leading to an
unrelocated/incorrect _rtld_local_ro address.

84e02af1eb tickled GCC powerpc32 to
reorder the GOT load before relative relocations, leading to ld.so
crash. This is similar to the m68k jump table reordering issue fixed by
a8e9b5b807.

Move code after self relocation into _dl_start_final to avoid the
reordering. This fixes powerpc32 and may help other architectures when
ELF_DYNAMIC_RELOCATE is simplified in the future.
2022-04-25 10:30:27 -07:00
Florian Weimer
198abcbb94 Default to --with-default-link=no (bug 25812)
This is necessary to place the libio vtables into the RELRO segment.
New tests elf/tst-relro-ldso and elf/tst-relro-libc are added to
verify that this is what actually happens.

The new tests fail on ia64 due to lack of (default) RELRO support
inbutils, so they are XFAILed there.
2022-04-22 10:59:03 +02:00
Florian Weimer
30035d6772 scripts: Add glibcelf.py module
Hopefully, this will lead to tests that are easier to maintain.  The
current approach of parsing readelf -W output using regular expressions
is not necessarily easier than parsing the ELF data directly.

This module is still somewhat incomplete (e.g., coverage of relocation
types and versioning information is missing), but it is sufficient to
perform basic symbol analysis or program header analysis.

The EM_* mapping for architecture-specific constant classes (e.g.,
SttX86_64) is not yet implemented.  The classes are defined for the
benefit of elf/tst-glibcelf.py.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-04-22 10:58:32 +02:00
Fangrui Song
84e02af1eb elf: Move elf_dynamic_do_Rel RTLD_BOOTSTRAP branches outside
elf_dynamic_do_Rel checks RTLD_BOOTSTRAP in several #ifdef branches.
Create an outside RTLD_BOOTSTRAP branch to simplify reasoning about the
function at the cost of a few duplicate lines.

Since dl_naudit is zero in RTLD_BOOTSTRAP code, the RTLD_BOOTSTRAP
branch can avoid _dl_audit_symbind calls to decrease code size.

Reviewed-by: Adheemrval Zanella  <adhemerval.zanella@linaro.org>
2022-04-20 13:52:45 -07:00
Fangrui Song
3e9acce8c5 elf: Remove __libc_init_secure
After 73fc4e28b9,
__libc_enable_secure_decided is always 0 and a statically linked
executable may overwrite __libc_enable_secure without considering
AT_SECURE.

The __libc_enable_secure has been correctly initialized in _dl_aux_init,
so just remove __libc_enable_secure_decided and __libc_init_secure.
This allows us to remove some startup_get*id functions from
22b79ed7f4.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-04-19 15:52:27 -07:00
Stefan Liebler
2376944b9e S390: Add new s390 platform z16.
The new IBM z16 is added to platform string array.
The macro _DL_PLATFORMS_COUNT is incremented.

_dl_hwcaps_subdir is extended by "z16" if HWCAP_S390_VXRS_PDE2
is set. HWCAP_S390_NNPA is not tested in _dl_hwcaps_subdirs_active
as those instructions may be replaced or removed in future.

tst-glibc-hwcaps.c is extended in order to test z16 via new marker5.

A fatal glibc error is dumped if glibc was build with architecture
level set for z16, but run on an older machine. (See dl-hwcap-check.h)
2022-04-14 10:37:45 +02:00
Noah Goldstein
535e935a28 Replace {u}int_fast{16|32} with {u}int32_t
On 32-bit machines this has no affect. On 64-bit machines
{u}int_fast{16|32} are set as {u}int64_t which is often not
ideal. Particularly x86_64 this change both saves code size and
may save instruction cost.

Full xcheck passes on x86_64.
2022-04-13 21:23:04 -05:00
Florian Weimer
4a41fc3cd9 elf: Fix memory leak in _dl_find_object_update (bug 29062)
The count can be zero if an object has already been loaded as
an indirect dependency (so that l_searchlist.r_list in its link
map is still NULL) is promoted to global scope via RTLD_GLOBAL.

Fixes commit 5d28a8962d ("elf: Add _dl_find_object function").
2022-04-13 14:19:04 +02:00
Stefan Liebler
5325233313 S390: Fix elf/tst-audit25[ab]
If glibc is configured with --disable-default-pie and build on
s390 with -O3, the tests elf/tst-audit25a and elf/tst-audit25b are
failing as there are additional la_symbind lines for free and malloc.
It turns out that those belong to the executable. In fact those are
the PLT-stubs. Furthermore la_symbind is also called for calloc and
realloc symbols, but those belong to libc.

Those functions are not called at all, but dlsym'ed in
elf/dl-minimal.c:
__rtld_malloc_init_real (struct link_map *main_map)
{
...
  void *new_calloc = lookup_malloc_symbol (main_map, "calloc", &version);
  void *new_free = lookup_malloc_symbol (main_map, "free", &version);
  void *new_malloc = lookup_malloc_symbol (main_map, "malloc", &version);
  void *new_realloc = lookup_malloc_symbol (main_map, "realloc", &version);
...
}

Therefore, this commit just ignored symbols with LA_SYMB_DLSYM flag.
Reviewed-by: Adheemrval Zanella  <adhemerval.zanella@linaro.org>
2022-04-07 20:38:23 +02:00
DJ Delorie
2fe64148a8 Allow for unpriviledged nested containers
If the build itself is run in a container, we may not be able to
fully set up a nested container for test-container testing.
Notably is the mounting of /proc, since it's critical that it
be mounted from within the same PID namespace as its users, and
thus cannot be bind mounted from outside the container like other
mounts.

This patch defaults to using the parent's PID namespace instead of
creating a new one, as this is more likely to be allowed.

If the test needs an isolated PID namespace, it should add the "pidns"
command to its init script.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-04-04 14:17:08 -04:00
Adhemerval Zanella
bc02f1fa2f elf: Remove unused functions from tst-audit25(a,b) 2022-03-31 09:12:16 -03:00
Adhemerval Zanella
f60510ddaf elf: Remove unused variables in tests
Checked on x86_64-linux-gnu and i686-linux-gnu.
2022-03-31 08:59:23 -03:00
Adhemerval Zanella
b2cd93fce6 elf: Fix wrong fscanf usage on tst-pldd
To take in consideration the extra '\0'.

Checked on x86_64-linux-gnu.
2022-03-31 08:57:59 -03:00
Florian Weimer
73fc4e28b9 Linux: Consolidate auxiliary vector parsing (redo)
And optimize it slightly.

This is commit 8c8510ab27 revised.

In _dl_aux_init in elf/dl-support.c, use an explicit loop
and -fno-tree-loop-distribute-patterns to avoid memset.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2022-02-28 11:50:41 +01:00
H.J. Lu
1fe00d3eb6 build: Properly generate .d dependency files [BZ #28922]
1. Also generate .d dependency files for $(tests-container) and
$(tests-printers).
2. elf: Add tst-auditmod17.os to extra-test-objs.
3. iconv: Add tst-gconv-init-failure-mod.os to extra-test-objs.
4. malloc: Rename extra-tests-objs to extra-test-objs.
5. linux: Add tst-sysconf-iov_max-uapi.o to extra-test-objs.
6. x86_64: Add tst-x86_64mod-1.o, tst-platformmod-2.o, test-libmvec.o,
test-libmvec-avx.o, test-libmvec-avx2.o and test-libmvec-avx512f.o to
extra-test-objs.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-02-25 10:35:45 -08:00
H.J. Lu
2c0915cbf5 elf: Check invalid hole in PT_LOAD segments [BZ #28838]
Changes in v2:

1. Update commit log.

commit 163f625cf9
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Tue Dec 21 12:35:47 2021 -0800

    elf: Remove excessive p_align check on PT_LOAD segments [BZ #28688]

removed the p_align check against the page size.  It caused the loader
error or crash on elf/tst-p_align3 when loading elf/tst-p_alignmod3.so,
which has the invalid p_align in PT_LOAD segments, added by

commit d8d94863ef
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Tue Dec 21 13:42:28 2021 -0800

The loader failure caused by a negative length passed to __mprotect is
random, depending on architecture and toolchain.  Update _dl_map_segments
to detect invalid holes.  This fixes BZ #28838.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-02-21 07:57:18 -08:00
Florian Weimer
d96d2995c1 Revert "Linux: Consolidate auxiliary vector parsing"
This reverts commit 8c8510ab27.  The
revert is not perfect because the commit included a bug fix for
_dl_sysdep_start with an empty argv, introduced in commit
2d47fa6862 ("Linux: Remove
DL_FIND_ARG_COMPONENTS"), and this bug fix is kept.

The revert is necessary because the reverted commit introduced an
early memset call on aarch64, which leads to crash due to lack of TCB
initialization.
2022-02-11 17:10:59 +01:00
Adhemerval Zanella
144761540a elf: Remove LD_USE_LOAD_BIAS
It is solely for prelink with PIE executables [1].

[1] https://sourceware.org/legacy-ml/libc-hacker/2003-11/msg00127.html

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-02-10 09:18:15 -03:00
Adhemerval Zanella
d7703d3176 malloc: Remove LD_TRACE_PRELINKING usage from mtrace
The fix for BZ#22716 replacde LD_TRACE_LOADED_OBJECTS with
LD_TRACE_PRELINKING so mtrace could record executable address
position.

To provide the same information, LD_TRACE_LOADED_OBJECTS is
extended where a value or '2' also prints the executable address
as well.  It avoid adding another loader environment variable
to be used solely for mtrace.  The vDSO will be printed as
a default library (with '=>' pointing the same name), which is
ok since both mtrace and ldd already handles it.

The mtrace script is changed to also parse the new format.  To
correctly support PIE and non-PIE executables, both the default
mtrace address and the one calculated as used (it fixes mtrace
for non-PIE exectuable as for BZ#22716 for PIE).

Checked on x86_64-linux-gnu.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-02-10 09:16:13 -03:00
Adhemerval Zanella
6628c742b2 elf: Remove prelink support
Prelinked binaries and libraries still work, the dynamic tags
DT_GNU_PRELINKED, DT_GNU_LIBLIST, DT_GNU_CONFLICT just ignored
(meaning the process is reallocated as default).

The loader environment variable TRACE_PRELINKING is also removed,
since it used solely on prelink.

Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-02-10 09:16:12 -03:00
Florian Weimer
8c8510ab27 Linux: Consolidate auxiliary vector parsing
And optimize it slightly.

The large switch statement in _dl_sysdep_start can be replaced with
a large array.  This reduces source code and binary size.  On
i686-linux-gnu:

Before:

   text	   data	    bss	    dec	    hex	filename
   7791	     12	      0	   7803	   1e7b	elf/dl-sysdep.os

After:

   text	   data	    bss	    dec	    hex	filename
   7135	     12	      0	   7147	   1beb	elf/dl-sysdep.os

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-02-10 11:51:55 +01:00
Florian Weimer
91c0a47ffb elf: Merge dl-sysdep.c into the Linux version
The generic version is the de-facto Linux implementation.  It
requires an auxiliary vector, so Hurd does not use it.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-02-10 11:50:52 +01:00