Commit Graph

869 Commits

Author SHA1 Message Date
Konstantin Belousov
529ab5a759 rtld: initialize default dlerror_seen_val as true
There should be no error after startup.

PR:	255698
Reported by:	Eugene M. Kim <astralblue@gmail.com>
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2021-05-13 02:31:29 +03:00
Konstantin Belousov
630caa95d4 rtld: preserve the 'seen' state of the dlerror message in errmsg_save()
rtld preserves its current error message around calls to user init/fini
lists, to not override original error with potential secondary errors
caused by user code recursing into rtld.  After 4d9128da54,
the preservation of the string itself is not enough, the 'seen'
indicator must be preserved as well.  Otherwise, since new code does not
clear string (it cannot), call to _rtld_error() from errmsg_restore()
revived whatever message was consumed last.

Change errmsg_save() to return structure recording both 'seen' indicator
and the message, if any.

PR:	255698
Reported by:	Eugene M. Kim <astralblue@gmail.com>
Sponsored by:	The FreeBSD Foundation
MFC after:	3 days
2021-05-11 02:47:00 +03:00
Konstantin Belousov
9b33518ada rtld_lock.h: add some comments about versioning of struct RtldLockInfo
Sponsored by:	The FreeBSD Foundation
MFC after:	6 days
2021-04-11 11:16:13 +03:00
Konstantin Belousov
4d9128da54 rtld: make dlerror() thread-local
PR:	95339
Discussed with:	arichardson
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D29633
2021-04-10 17:33:34 +03:00
Konstantin Belousov
08bfbd4359 rtld: workaround for broken ABI
Right now, libthr does not initialize RtldLockInfo.rtli_version when calling
_rtld_thread_init(), which makes versioning the interface troublesome.

Add a workaround: if the calling object of _rtld_thread_init() exports
the "_pli_rtli_version" symbol, then consider rtli_version initialized.
Otherwise, forcibly set it to RTLI_VERSION_ONE, currently defined as
RTLI_VERSION.

Export "_pli_rtli_version" from libthr and properly initialize rtli_version.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D29633
2021-04-10 17:33:33 +03:00
Konstantin Belousov
4d7f08c84b rtld: unstaticise lockinfo and obj_from_addr()
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D29633
2021-04-10 17:33:33 +03:00
Konstantin Belousov
e8b9c508b7 rtld: use _get_tp() in __tls_get_addr()
This eliminates some non-trivial amount of code duplication, where done.
Only x86 and mips are handled right now.

Tested by:      bdragon (powerpc), mhorne (riscv)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D29623
2021-04-09 23:46:24 +03:00
Konstantin Belousov
7cb32a0d03 rtld: avoid recursing on rtld_bind_lock for write
This fixes a regression in d36d681615, where the call to
__tls_get_address() was performed under rtld_bind_lock write-locked.
Instead use tls_get_addr_slow() directly, with locked = true.

Reported by:	jkim, many others
Tested by:	jkim, bdragon (powerpc), mhorne (riscv)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D29623
2021-04-09 23:46:24 +03:00
Konstantin Belousov
8950804842 rtld: allow to use tls_get_addr_slow() from context where rtld_bind_lock is locked
Explicit locked parameter is added

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D29623
2021-04-09 23:46:24 +03:00
Konstantin Belousov
85d846b369 rtld: style tls_get_addr_slow
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D29623
2021-04-09 23:46:24 +03:00
Konstantin Belousov
99c2ce7ef1 rtld: define TLS_DTV_OFFSET on all architectures
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D29623
2021-04-09 23:46:24 +03:00
Konstantin Belousov
34ca6025dd rtld_lock.h: Expand scope for IN_RTLD to avoid some conflicts with libc
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D29623
2021-04-09 23:46:23 +03:00
Konstantin Belousov
f61ecf60cf rtld/x86/reloc.c: style
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D29623
2021-04-09 23:46:23 +03:00
Konstantin Belousov
38e0610df7 rtld_lock.h: remove tautological extern's
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D29623
2021-04-09 23:46:23 +03:00
Andrew Turner
4d9488674f Remove the last users of ARM_TP_ADDRESS
This was only needed on 32-bit arm prior to ARMv6. As we only support
ARMv6 or later remove it.

Reviewed by:	mannu
Sponsored by:	Innovate UK
Differential Revision:	https://reviews.freebsd.org/D29624
2021-04-08 07:52:54 +00:00
Konstantin Belousov
d36d681615 rtld dl_iterate_phdr(): dlpi_tls_data is wrong
dl_iterate_phdr() dlpi_tls_data should provide the TLS module segment
address, and not the TLS init segment address as it does now.

Reported by:	emacsray@gmail.com
PR:	254774
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2021-04-06 03:23:08 +03:00
Mariusz Zaborski
e086aff91c rtld: fix the man page
In f90218886f in man page I used LD_PRELOAD_PATH_FDS instead of
LD_PRELOAD_FDS.

Reported by:	rpokala
2021-03-25 00:51:44 +01:00
Mariusz Zaborski
f90218886f rtld: introduce PRELOAD_FDS
The new PRELOAD_FDS variable accepts a list of file descriptors
that should be loaded into the process.

This may be used to optimize a loading process - in the case when
we already have a file descriptor to the library; we don't have
to look into multiple PATH to find it.

It may also be used in capability mode to load a single additional
library without the need to open a directory that contains it.

The last use of this functionality t may be a race-free method
of loading libraries.

Reviewed by:	kib, markj
Differential Revision:	https://reviews.freebsd.org/D29334
2021-03-24 23:40:48 +01:00
Mariusz Zaborski
852a88a1d9 rtld: style nits
No functional change intended.

Requested by:	kib
2021-03-24 23:40:48 +01:00
Ed Maste
7f72497ef7 libc: Use musl's optimized strchr and strchrnul
Parentheses added to HASZERO macro to avoid a GCC warning, and formatted
with clang-format as we have adopted these and don't consider them
'contrib' code.

Obtained from:	musl (snapshot at commit 4d0a82170a25)
Reviewed by:	kib (libc integration), mjg (both earlier)
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D17630
2021-03-01 21:09:59 -05:00
David Chisnall
43d44842ae rtld: Fix null-pointer dereference
When a library is opened via fdlopen, it has a null pointer for its path
and so _rtld_bind can crash as a result of passing the null pointer to
basename() (which passes it to strrchr(), which doesn't do a null check).

PR:	253081
Submitted by:	theraven
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D28442
2021-02-02 16:14:16 +02:00
Ed Maste
613a08cfa2 rtld: map without PROT_EXEC for relocation
This makes text segment relocation work under W^X.

Submitted by:	Greg V <greg@unrelenting.technology> (original version)
Reviewed by:	kib
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D27953
2021-01-05 10:57:14 -05:00
Konstantin Belousov
741d78126b rtld: call close(2) after errno is saved
to prevent obliteration of error value from the original syscall.
Also improve error message for short read.

Submitted by:	Konrad Sewiłło-Jopek
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D27864
2021-01-02 04:43:32 +02:00
Ryan Libby
63f93c7e11 rtld-elf: link libcompiler_rt on all architectures
Statically link rtld-elf with libcompiler_rt on all architectures so
that we don't need to try to pick and choose the bits we need from it
for each architecture (we now leave that to the linker).  Compilers may
emit calls to support functions in this library, but because of the use
of the linker flag -nostdlib for rtld's special needs, the library is
not linked as normal.

Previously we had two different solutions.  On some architectures, we
were able to extract reimplementations of the necessary builtin
functions from our special build of libc.  On ARM, we just linked
libcompiler_rt.

This is motivated by the same issue as D26199 and D27665, but should be
a simpler solution that will apply to all architectures.

Reviewed by:	arichardson, kib
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D27736
2020-12-28 00:44:25 -08:00
Ryan Libby
85b8932d0a Revert "rtld-elf: link udivmoddi4 from compiler_rt"
This reverts commit bce2cff0bc.

Revert D27665 in favor of a more general fix coming in D27736.
2020-12-28 00:44:25 -08:00
Marius Strobl
b58c853edf rtld-elf(1): remove obsolete pre_init() hook
It's no longer used since 600ee699ed
and r358358 respectively.
2020-12-25 19:47:46 +01:00
Ryan Libby
bce2cff0bc rtld-elf: link udivmoddi4 from compiler_rt
This fixes the gcc9 build of rtld-elf32 on amd64, which needed an
implementation of udivmoddi4.

rtld-elf uses certain functions normally found in libc, and so it
includes certain files from libc in its own build.  It has two
mechanisms to include files from libc: one that rebuilds source files in
the rtld-elf environment, and one that extracts object files from a
purpose-built no-SSP PIC archive.

In addition to libc functions, rtld-elf may need to link functions
normally found in libcompiler_rt (formerly libgcc).  Now, add an ability
to rebuild libcompiler_rt source files in the rtld-elf environment.  We
don't yet have a need for an object file extraction mechanism.

libcompiler_rt could also supply udivdi3 and umoddi3, but leave them
alone for now.

Reviewed by:	arichardson, kib
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D27665
2020-12-19 08:38:31 +00:00
Ryan Libby
198a0e58ec rtld-libc: fix incremental build
ar cr is an update of an archive, not a creation of a new one.  During
incremental builds (e.g. with meta mode) the archive was not getting
cleaned, and so could retain now-deleted objects from previous builds.
Now, delete the archive before creating/updating it.

Reviewed by:	arichardson, bdrewery, kib
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D27663
2020-12-19 08:38:27 +00:00
Conrad Meyer
78599c32ef Add CFI start/end proc directives to arm64, i386, and ppc
Follow-up to r353959 and r368070: do the same for other architectures.

arm32 already seems to use its own .fnstart/.fnend directives, which
appear to be ARM-specific variants of the same thing.  Likewise, MIPS
uses .frame directives.

Reviewed by:	arichardson
Differential Revision:	https://reviews.freebsd.org/D27387
2020-12-05 00:33:28 +00:00
Konstantin Belousov
71df6a153f rtld: bump r_debug.r_version to 1 from current 0.
Add r_ldbase.

Requested and reviewed by:	emaste
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D27429
2020-12-01 22:28:01 +00:00
Gordon Bergling
812b09037d Fix a few mandoc issues
- whitespace at end of input line
- skipping paragraph macro: Pp at the end of Sh
- new sentence, new line
- consider using OS macro: Fx
- AUTHORS section without An macro
- skipping paragraph macro: Pp before Ss
2020-10-09 15:14:19 +00:00
Kyle Evans
7cc42f6d25 Do a sweep and remove most WARNS=6 settings
Repeating the default WARNS here makes it slightly more difficult to
experiment with default WARNS changes, e.g. if we did something absolutely
bananas and introduced a WARNS=7 and wanted to try lifting the default to
that.

Drop most of them; there is one in the blake2 kernel module, but I suspect
it should be dropped -- the default WARNS in the rest of the build doesn't
currently apply to kernel modules, and I haven't put too much thought into
whether it makes sense to make it so.
2020-10-01 01:10:51 +00:00
Brandon Bergren
24faccc241 [PowerPC64LE] Use a shared LIBC_ARCH for powerpc64le.
Given that we have converted to ELFv2 for BE already, endianness is the only
difference between the two ARCHs.

As such, there is no need to differentiate LIBC_ARCH between the two.

Combining them like this lets us avoid needing to have two copies of several
bits for no good reason.

Sponsored by:	Tag1 Consulting, Inc.
2020-09-23 00:21:51 +00:00
Konstantin Belousov
1db23efb83 rtld: pass argc/argv/env to dso inits.
This is consistent with how array inits are called, and also makes us
more compatible with glibc environment.

Requested by:	Alex S <iwtcex@gmail.com>
PR:	249162
Reviewed by:	dim, emaste
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D26351
2020-09-07 21:32:27 +00:00
Konstantin Belousov
12cb97fb37 Undo 'fix off by one' part of r365360.
Noted by:	emaste
Sponsored by:	The FreeBSD Foundation
MFC after:	6 days
2020-09-05 22:48:27 +00:00
Konstantin Belousov
500433057e rtld: do not refuse to relocate objects without dynamic symtabs.
Such objects can still have valid relocations not requiring symbolic
references.

PR:	249121
Reported by:	wsh@riski.sh
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2020-09-05 22:44:38 +00:00
Konstantin Belousov
2b49b95cfa rtld: do not process absent dynamic.
If object has no dynamic phdr, do not try to dereference NULL.  This
means that we cannot process any relocation, and that there cannot be
symbols defined, but it is up to static linker to produce meaningful
objects.

PR:	249121
Reported by:	wsh@riski.sh
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2020-09-05 22:41:31 +00:00
Konstantin Belousov
5d6d106cf6 rtld: Handle ELF dso with program headers outside the first page.
Reported by:	Alex Arslan <alex.arslan@julialang.org>
PR:	229708
Reviewed by:	dim (previous version), emaste
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D26323
2020-09-05 10:16:24 +00:00
Brooks Davis
29e1fceb73 Maintain a stack alignment of 16-bytes.
This violated the RISC-V 64-bit ABI.  On CheriBSD this manifested as
a trap when attempting to store 16-byte aligned types while zeroing
the stack.

Reported by:	CHERI, jrtc27
Reviewed by:	mhorne, br
Obtained from:	CheriBSD
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D26327
2020-09-04 21:46:10 +00:00
Xin LI
941791759c Don't explicitly specify c99 or gnu99 as the default is now gnu99.
MFC after:	2 weeks
2020-08-17 05:57:02 +00:00
John Baldwin
e9751a84dd Include FreeBSD ABI tag note in the ELF runtime loader.
Reviewed by:	kib
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D25306
2020-07-16 22:01:01 +00:00
Leandro Lupori
a5467d6ca2 Handle non-PLT GNU IFUNC relocations in rtld
In the last IFUNC related changes to rtld, the code that handled non-PLT
GNU IFUNC relocations ended up getting lost. This could leave some
relocations unhandled, causing crashes or misbehavior. This change restores
the handling of these relocations, but now together with the other IFUNC
relocations, allowing resolvers to reference external symbols.

Reviewed by:	kib
MFC after:	2 weeks
Sponsored by:	Eldorado Research Institute (eldorado.org.br)
Differential Revision:	https://reviews.freebsd.org/D25550
2020-07-06 11:57:59 +00:00
Konstantin Belousov
7e400f1ade rtld: Apply relro to itself.
Reviewed by:	emaste
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D25319
2020-06-18 23:07:58 +00:00
Konstantin Belousov
e0b322ae78 rtld: Parse own phdr and notes.
Reviewed by:	emaste
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D25319
2020-06-18 23:06:05 +00:00
Konstantin Belousov
512baba6a5 rtld: Allow to load ET_DYN && DF_1_PIE when tracing.
This makes old ldd to still work on newer tagged PIE binaries.

Also move debug line for hashes before both decisions to not load are
done, so that the end of digest_dynamic() processing and reason to not
load or load is seen in debug trace.

Noted by:	jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2020-06-16 21:29:02 +00:00
Konstantin Belousov
53b1c32035 rtld: Add debug line for dlopen_object().
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2020-06-16 21:25:58 +00:00
Konstantin Belousov
de34401534 Systematically pass RTLD_LO_TRACE to load_needed_objects().
Which makes all calls to load_object() to observe the flag, except the
calls for preloaded DSOs.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2020-06-16 21:23:39 +00:00
Konstantin Belousov
510b525fa5 rtld: set osrel when in the direct exec mode.
Rtld itself is a shared object which does not have vendor note, so
after the direct exec of ld-elf.so.1 process has p_osrel set to zero.
This affects the ABI of syscalls.

Set osrel to the __FreeBSD_version value at compile time right after
rtld identified direct exec mode.  Then, switch to the osrel read from
the binary note or zero if no note, right before starting calling
ifunc resolvers, which is the first byte of the user code.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2020-06-12 22:10:03 +00:00
Konstantin Belousov
daf5a897b9 Uppercase 'dso' to indicate that it is abbreviation.
Suggested by:	arichardson
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2020-06-02 17:33:10 +00:00
Konstantin Belousov
c1a813209c Do not allow to load ET_DYN object with DF_1_PIE flag set.
Linkers are supposed to mark PIE binaries with DF_1_PIE, such binary
cannot be correctly and usefully loaded neither by dlopen(3) nor as a
dependency of other object.  For instance, we cannot do anything
useful with COPY relocations, among other things.

Glibc already added similar restriction.

Requested and reviewed by:	emaste
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D25086
2020-06-02 16:20:58 +00:00