A recent commit, apparently commit
6c6fce572f "elf: Remove /etc/suid-debug
support", resulted in localplt failures for i686-gnu and x86_64-gnu:
Missing required PLT reference: ld.so: __access_noerrno
After that commit, __access_noerrno is actually no longer used at all.
So rather than just removing the localplt expectation for that symbol
for Hurd, completely remove all definitions of and references to that
symbol.
Tested for x86_64, and with build-many-glibcs.py for i686-gnu and
x86_64-gnu.
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>
The include cleanup on dl-minimal.c removed too much for some
targets.
Also for Hurd, __sbrk is removed from localplt.data now that
tunables allocated memory through mmap.
Checked with a build for all affected architectures.
Wean mtrace away from the malloc hooks and move them into the debug
DSO. Split the API away from the implementation so that we can add
the API to libc.so as well as libc_malloc_debug.so, with the libc
implementations being empty.
Update localplt data since memalign no longer has any callers after
this change.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
We need NO_RTLD_HIDDEN because of the need for PLT calls in ld.so.
See Roland's comment in
https://sourceware.org/bugzilla/show_bug.cgi?id=15605
"in the Hurd it's crucial that calls like __mmap be the libc ones
instead of the rtld-local ones after the bootstrap phase, when the
dynamic linker is being used for dlopen and the like."
We used to just avoid all hidden use in the rtld ; this commit switches to
keeping only those that should use PLT calls, i.e. essentially those defined in
sysdeps/mach/hurd/dl-sysdep.c:
__assert_fail
__assert_perror_fail
__*stat64
_exit
This fixes a few startup issues, notably the call to __tunable_get_val that is
made before PLTs are set up.
and add _nocancel variants.
* sysdeps/mach/hurd/write.c (__libc_write): Call __write_nocancel
surrounded by enabling async cancel, to replace implementation moved
to...
* sysdeps/mach/hurd/write_nocancel.c (__write_nocancel): ... here.
* sysdeps/mach/hurd/pwrite64.c (__libc_pwrite64): Call
__pwrite64_nocancel surrounded by enabling async cancel, to replace
implementation moved to...
* sysdeps/mach/hurd/pwrite64_nocancel.c (__pwrite64_nocancel): ... here.
* sysdeps/mach/hurd/Makefile (sysdep_routines): Add write_nocancel and
pwrite64_nocancel.
* sysdeps/mach/hurd/not-cancel.h (__write_nocancel,
__pwrite64_nocancel): Replace macros with prototypes with a hidden proto on
libc.
* sysdeps/mach/hurd/dl-sysdep.c (__write_nocancel): New alias, check
that it is not hidden.
* sysdeps/mach/hurd/Versions (libc.GLIBC_PRIVATE): Add __write_nocancel.
(ld.GLIBC_PRIVATE): Add __write_nocancel.
* sysdeps/mach/hurd/i386/localplt.data (__write_nocancel): Add
reference.
and add _nocancel variants.
* sysdeps/mach/hurd/pread64.c (__libc_pread64): Call __pread64_nocancel
surrounded by enabling async cancel, to replace implementation moved to...
* sysdeps/mach/hurd/pread64_nocancel.c (__pread64_nocancel): ... here.
* sysdeps/mach/hurd/read.c (__libc_read): Call __read_nocancel surrounded by
enabling async cancel, to replace implementation moved to...
* sysdeps/mach/hurd/read_nocancel.c (__read_nocancel): ... here.
* sysdeps/mach/hurd/Makefile (sysdep_routines): Add read_nocancel and
pread64_nocancel.
* sysdeps/mach/hurd/not-cancel.h (__read_nocancel, __pread64_nocancel):
Replace macros with prototypes with a hidden proto on libc.
* sysdeps/mach/hurd/dl-sysdep.c: Include <not-cancel.h>.
(__pread64_nocancel): New alias, check that it is not hidden.
(__read_nocancel): New alias, check that it is not hidden.
* sysdeps/mach/hurd/Versions (libc.GLIBC_PRIVATE): Add __read_nocancel and
__pread64_nocancel.
(ld.GLIBC_2.1): Add __pread64.
(ld.GLIBC_PRIVATE): Add __read_nocancel and __pread64_nocancel.
* sysdeps/mach/hurd/i386/ld.abilist (__pread64): Add symbol.
* sysdeps/mach/hurd/i386/localplt.data (__read_nocancel, __pread64,
__pread64_nocancel): Add references.
This change makes it easier to set a breakpoint on these calls.
This also addresses the issue that including <ldsodefs.h> without
<unistd.h> does not result usable _dl_*printf macros because of the
use of the STD*_FILENO macros there.
(The private symbol for _dl_fatal_printf will go away again
once the exception handling implementation is unified between
libc and ld.so.)
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Exporting functions and relying on symbol interposition from libc.so
makes the choice of implementation dependent on DT_NEEDED order, which
is not what some compiler drivers expect.
This commit replaces one magic mechanism (symbol interposition) with
another one (preprocessor-/compiler-based redirection). This makes
the hand-over from the minimal malloc to the full malloc more
explicit.
Removing the ABI symbols is backwards-compatible because libc.so is
always in scope, and the dynamic loader will find the malloc-related
symbols there since commit f0b2132b35
("ld.so: Support moving versioned symbols between sonames
[BZ #24741]").
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
After commit f7649d5780 ("dlopen: Do not
block signals"), the dynamic linker no longer uses sigprocmask, which
means that it does not have to be made available explicitly on hurd.
This reverts commit 892badc9bb
("hurd: Make __sigprocmask GLIBC_PRIVATE") and commit
d5ed9ba29a ("hurd: Fix ld.so link"),
but keeps the comment changes from the second commit.
ld.so symbols to be overriden by libc need to be extern to really get
overriden. __access happens to have never been exposed, putting it to
GLIBC_PRIVATE.
ld.so symbols to be overriden by libc need to be extern to really get
overriden. __getcwd happens to have never been exposed, putting it to
GLIBC_PRIVATE.
ld.so symbols to be overriden by libc need to be extern to really get
overriden.
* sysdeps/mach/hurd/not-errno.h: New file.
* sysdeps/mach/hurd/i386/localplt.data: Update accordingly.
ld.so symbols to be overriden by libc need to be extern to really get
overriden.
* sysdeps/mach/hurd/dl-unistd.h (__access, __brk, __lseek, __read,
__sbrk): Do not set attribute_hidden.
* sysdeps/mach/hurd/i386/ld.abilist: Update accordingly.
* sysdeps/mach/hurd/i386/localplt.data: Update accordingly.
ld.so symbols to be overriden by libc need to be extern to really get
overriden.
More fixes are needed to avoid the hidden attribute.
* sysdeps/mach/hurd/Versions (libc): Make __access and
__access_noerrno external so they can override the ld symbols.
(ld): Make __access, __read, __sbrk, __strtoul_internal, __write,
__writev, __open64, __access_noerrno extern so they can be overrided.
* sysdeps/mach/hurd/i386/libc.abilist: Update accordingly.
* sysdeps/mach/hurd/i386/ld.abilist: Update accordingly.
