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Make __rseq_size useful for feature detection (RHEL-65280)

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Resolves: RHEL-65280
This commit is contained in:
Arjun Shankar 2025-03-06 17:10:59 +01:00
parent 025c5d4ac2
commit 6e489a733f
7 changed files with 567 additions and 1 deletions
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commit 8754a4133e154ca853e6765a3fe5c7a904c77626
Author: Joseph Myers <joseph@codesourcery.com>
Date: Fri May 26 15:03:31 2023 +0000
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.
diff --git a/elf/elf.h b/elf/elf.h
index 4738dfa28f6549fc..076d8e3f696c58f7 100644
--- a/elf/elf.h
+++ b/elf/elf.h
@@ -1205,6 +1205,9 @@ typedef struct
#define AT_HWCAP2 26 /* More machine-dependent hints about
processor capabilities. */
+#define AT_RSEQ_FEATURE_SIZE 27 /* rseq supported feature size. */
+#define AT_RSEQ_ALIGN 28 /* rseq allocation alignment. */
+
#define AT_EXECFN 31 /* Filename of executable. */
/* Pointer to the global system page used for system calls and other

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commit 2b92982e2369d292560793bee8e730f695f48ff3
Author: Michael Jeanson <mjeanson@efficios.com>
Date: Wed Jul 3 12:35:34 2024 -0400
nptl: fix potential merge of __rseq_* relro symbols
While working on a patch to add support for the extensible rseq ABI, we
came across an issue where a new 'const' variable would be merged with
the existing '__rseq_size' variable. We tracked this to the use of
'-fmerge-all-constants' which allows the compiler to merge identical
constant variables. This means that all 'const' variables in a compile
unit that are of the same size and are initialized to the same value can
be merged.
In this specific case, on 32 bit systems 'unsigned int' and 'ptrdiff_t'
are both 4 bytes and initialized to 0 which should trigger the merge.
However for reasons we haven't delved into when the attribute 'section
(".data.rel.ro")' is added to the mix, only variables of the same exact
types are merged. As far as we know this behavior is not specified
anywhere and could change with a new compiler version, hence this patch.
Move the definitions of these variables into an assembler file and add
hidden writable aliases for internal use. This has the added bonus of
removing the asm workaround to set the values on rseq registration.
Tested on Debian 12 with GCC 12.2.
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
diff --git a/elf/Makefile b/elf/Makefile
index e0a86a305c4dc2ed..ec0d67b1549823ad 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -69,6 +69,7 @@ dl-routines = \
dl-printf \
dl-profile \
dl-reloc \
+ dl-rseq-symbols \
dl-runtime \
dl-scope \
dl-setup_hash \
diff --git a/elf/dl-rseq-symbols.S b/elf/dl-rseq-symbols.S
new file mode 100644
index 0000000000000000..b4bba06a99b0a486
--- /dev/null
+++ b/elf/dl-rseq-symbols.S
@@ -0,0 +1,64 @@
+/* Define symbols used by rseq.
+ Copyright (C) 2024 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <sysdep.h>
+
+#if __WORDSIZE == 64
+#define RSEQ_OFFSET_SIZE 8
+#else
+#define RSEQ_OFFSET_SIZE 4
+#endif
+
+/* Some targets define a macro to denote the zero register. */
+#undef zero
+
+/* Define 2 symbols: '__rseq_size' is public const and '_rseq_size' (an
+ alias of '__rseq_size') is hidden and writable for internal use by the
+ dynamic linker which will initialize the value both symbols point to
+ before copy relocations take place. */
+
+ .globl __rseq_size
+ .type __rseq_size, %object
+ .size __rseq_size, 4
+ .hidden _rseq_size
+ .globl _rseq_size
+ .type _rseq_size, %object
+ .size _rseq_size, 4
+ .section .data.rel.ro
+ .balign 4
+__rseq_size:
+_rseq_size:
+ .zero 4
+
+/* Define 2 symbols: '__rseq_offset' is public const and '_rseq_offset' (an
+ alias of '__rseq_offset') is hidden and writable for internal use by the
+ dynamic linker which will initialize the value both symbols point to
+ before copy relocations take place. */
+
+ .globl __rseq_offset
+ .type __rseq_offset, %object
+ .size __rseq_offset, RSEQ_OFFSET_SIZE
+ .hidden _rseq_offset
+ .globl _rseq_offset
+ .type _rseq_offset, %object
+ .size _rseq_offset, RSEQ_OFFSET_SIZE
+ .section .data.rel.ro
+ .balign RSEQ_OFFSET_SIZE
+__rseq_offset:
+_rseq_offset:
+ .zero RSEQ_OFFSET_SIZE
diff --git a/sysdeps/nptl/dl-tls_init_tp.c b/sysdeps/nptl/dl-tls_init_tp.c
index d5f2587f1348441c..039080d7110f5064 100644
--- a/sysdeps/nptl/dl-tls_init_tp.c
+++ b/sysdeps/nptl/dl-tls_init_tp.c
@@ -45,8 +45,10 @@ rtld_mutex_dummy (pthread_mutex_t *lock)
#endif
const unsigned int __rseq_flags;
-const unsigned int __rseq_size attribute_relro;
-const ptrdiff_t __rseq_offset attribute_relro;
+
+/* The variables are in .data.relro but are not yet write-protected. */
+extern unsigned int _rseq_size attribute_hidden;
+extern ptrdiff_t _rseq_offset attribute_hidden;
void
__tls_pre_init_tp (void)
@@ -107,10 +109,7 @@ __tls_init_tp (void)
#endif
if (rseq_register_current_thread (pd, do_rseq))
{
- /* We need a writable view of the variables. They are in
- .data.relro and are not yet write-protected. */
- extern unsigned int size __asm__ ("__rseq_size");
- size = sizeof (pd->rseq_area);
+ _rseq_size = sizeof (pd->rseq_area);
}
#ifdef RSEQ_SIG
@@ -119,8 +118,7 @@ __tls_init_tp (void)
all targets support __thread_pointer, so set __rseq_offset only
if thre rseq registration may have happened because RSEQ_SIG is
defined. */
- extern ptrdiff_t offset __asm__ ("__rseq_offset");
- offset = (char *) &pd->rseq_area - (char *) __thread_pointer ();
+ _rseq_offset = (char *) &pd->rseq_area - (char *) __thread_pointer ();
#endif
}

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commit 2e456ccf0c34a056e3ccafac4a0c7effef14d918
Author: Florian Weimer <fweimer@redhat.com>
Date: Mon Jul 8 21:14:00 2024 +0200
Linux: Make __rseq_size useful for feature detection (bug 31965)
The __rseq_size value is now the active area of struct rseq
(so 20 initially), not the full struct size including padding
at the end (32 initially).
Update misc/tst-rseq to print some additional diagnostics.
Reviewed-by: Michael Jeanson <mjeanson@efficios.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
diff --git a/manual/threads.texi b/manual/threads.texi
index 3fd307e69a8029fa..42e824fcdbec60f6 100644
--- a/manual/threads.texi
+++ b/manual/threads.texi
@@ -1007,8 +1007,12 @@ This variable is either zero (if restartable sequence registration
failed or has been disabled) or the size of the restartable sequence
registration. This can be different from the size of @code{struct rseq}
if the kernel has extended the size of the registration. If
-registration is successful, @code{__rseq_size} is at least 32 (the
-initial size of @code{struct rseq}).
+registration is successful, @code{__rseq_size} is at least 20 (the
+initially active size of @code{struct rseq}).
+
+Previous versions of @theglibc{} set this to 32 even if the kernel only
+supported the initial area of 20 bytes because the value included unused
+padding at the end of the restartable sequence area.
@end deftypevar
@deftypevar {unsigned int} __rseq_flags
diff --git a/sysdeps/nptl/dl-tls_init_tp.c b/sysdeps/nptl/dl-tls_init_tp.c
index 039080d7110f5064..2f56281a02246a09 100644
--- a/sysdeps/nptl/dl-tls_init_tp.c
+++ b/sysdeps/nptl/dl-tls_init_tp.c
@@ -46,10 +46,6 @@ rtld_mutex_dummy (pthread_mutex_t *lock)
const unsigned int __rseq_flags;
-/* The variables are in .data.relro but are not yet write-protected. */
-extern unsigned int _rseq_size attribute_hidden;
-extern ptrdiff_t _rseq_offset attribute_hidden;
-
void
__tls_pre_init_tp (void)
{
@@ -108,9 +104,7 @@ __tls_init_tp (void)
do_rseq = TUNABLE_GET (rseq, int, NULL);
#endif
if (rseq_register_current_thread (pd, do_rseq))
- {
- _rseq_size = sizeof (pd->rseq_area);
- }
+ _rseq_size = RSEQ_AREA_SIZE_INITIAL_USED;
#ifdef RSEQ_SIG
/* This should be a compile-time constant, but the current
diff --git a/sysdeps/unix/sysv/linux/rseq-internal.h b/sysdeps/unix/sysv/linux/rseq-internal.h
index 9e8f99fd51a063b1..ccb16640133fa9e3 100644
--- a/sysdeps/unix/sysv/linux/rseq-internal.h
+++ b/sysdeps/unix/sysv/linux/rseq-internal.h
@@ -25,15 +25,34 @@
#include <stdio.h>
#include <sys/rseq.h>
+/* 32 is the initially required value for the area size. The
+ actually used rseq size may be less (20 bytes initially). */
+#define RSEQ_AREA_SIZE_INITIAL 32
+#define RSEQ_AREA_SIZE_INITIAL_USED 20
+
+/* The variables are in .data.relro but are not yet write-protected. */
+extern unsigned int _rseq_size attribute_hidden;
+extern ptrdiff_t _rseq_offset attribute_hidden;
+
#ifdef RSEQ_SIG
static inline bool
rseq_register_current_thread (struct pthread *self, bool do_rseq)
{
if (do_rseq)
{
+ unsigned int size;
+#if IS_IN (rtld)
+ /* Use the hidden symbol in ld.so. */
+ size = _rseq_size;
+#else
+ size = __rseq_size;
+#endif
+ if (size < RSEQ_AREA_SIZE_INITIAL)
+ /* The initial implementation used only 20 bytes out of 32,
+ but still expected size 32. */
+ size = RSEQ_AREA_SIZE_INITIAL;
int ret = INTERNAL_SYSCALL_CALL (rseq, &self->rseq_area,
- sizeof (self->rseq_area),
- 0, RSEQ_SIG);
+ size, 0, RSEQ_SIG);
if (!INTERNAL_SYSCALL_ERROR_P (ret))
return true;
}
diff --git a/sysdeps/unix/sysv/linux/tst-rseq.c b/sysdeps/unix/sysv/linux/tst-rseq.c
index 572c11166f8b6533..1d404db610c08fdf 100644
--- a/sysdeps/unix/sysv/linux/tst-rseq.c
+++ b/sysdeps/unix/sysv/linux/tst-rseq.c
@@ -29,6 +29,7 @@
# include <stdlib.h>
# include <string.h>
# include <syscall.h>
+# include <sys/auxv.h>
# include <thread_pointer.h>
# include <tls.h>
# include "tst-rseq.h"
@@ -42,7 +43,8 @@ do_rseq_main_test (void)
TEST_COMPARE (__rseq_flags, 0);
TEST_VERIFY ((char *) __thread_pointer () + __rseq_offset
== (char *) &pd->rseq_area);
- TEST_COMPARE (__rseq_size, sizeof (pd->rseq_area));
+ /* The current implementation only supports the initial size. */
+ TEST_COMPARE (__rseq_size, 20);
}
static void
@@ -52,6 +54,12 @@ do_rseq_test (void)
{
FAIL_UNSUPPORTED ("kernel does not support rseq, skipping test");
}
+ printf ("info: __rseq_size: %u\n", __rseq_size);
+ printf ("info: __rseq_offset: %td\n", __rseq_offset);
+ printf ("info: __rseq_flags: %u\n", __rseq_flags);
+ printf ("info: getauxval (AT_RSEQ_FEATURE_SIZE): %ld\n",
+ getauxval (AT_RSEQ_FEATURE_SIZE));
+ printf ("info: getauxval (AT_RSEQ_ALIGN): %ld\n", getauxval (AT_RSEQ_ALIGN));
do_rseq_main_test ();
}
#else /* RSEQ_SIG */

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commit 97f60abd25628425971f07e9b0e7f8eec0741235
Author: Michael Jeanson <mjeanson@efficios.com>
Date: Thu Nov 7 22:23:49 2024 +0100
nptl: initialize rseq area prior to registration
Per the rseq syscall documentation, 3 fields are required to be
initialized by userspace prior to registration, they are 'cpu_id',
'rseq_cs' and 'flags'. Since we have no guarantee that 'struct pthread'
is cleared on all architectures, explicitly set those 3 fields prior to
registration.
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
diff --git a/nptl/descr.h b/nptl/descr.h
index 6484e3703f9a0a97..c08c5149c7239e7c 100644
--- a/nptl/descr.h
+++ b/nptl/descr.h
@@ -424,6 +424,8 @@ struct pthread
{
uint32_t cpu_id_start;
uint32_t cpu_id;
+ uint64_t rseq_cs;
+ uint32_t flags;
};
char pad[32]; /* Original rseq area size. */
} rseq_area __attribute__ ((aligned (32)));
diff --git a/sysdeps/unix/sysv/linux/rseq-internal.h b/sysdeps/unix/sysv/linux/rseq-internal.h
index ccb16640133fa9e3..7e70ae7ebdee4917 100644
--- a/sysdeps/unix/sysv/linux/rseq-internal.h
+++ b/sysdeps/unix/sysv/linux/rseq-internal.h
@@ -51,11 +51,21 @@ rseq_register_current_thread (struct pthread *self, bool do_rseq)
/* The initial implementation used only 20 bytes out of 32,
but still expected size 32. */
size = RSEQ_AREA_SIZE_INITIAL;
+
+ /* Initialize the rseq fields that are read by the kernel on
+ registration, there is no guarantee that struct pthread is
+ cleared on all architectures. */
+ THREAD_SETMEM (self, rseq_area.cpu_id, RSEQ_CPU_ID_UNINITIALIZED);
+ THREAD_SETMEM (self, rseq_area.rseq_cs, 0);
+ THREAD_SETMEM (self, rseq_area.flags, 0);
+
int ret = INTERNAL_SYSCALL_CALL (rseq, &self->rseq_area,
size, 0, RSEQ_SIG);
if (!INTERNAL_SYSCALL_ERROR_P (ret))
return true;
}
+ /* When rseq is disabled by tunables or the registration fails, inform
+ userspace by setting 'cpu_id' to RSEQ_CPU_ID_REGISTRATION_FAILED. */
THREAD_SETMEM (self, rseq_area.cpu_id, RSEQ_CPU_ID_REGISTRATION_FAILED);
return false;
}

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commit d9f40387d3305d97e30a8cf8724218c42a63680a
Author: Michael Jeanson <mjeanson@efficios.com>
Date: Wed Nov 20 14:15:42 2024 -0500
nptl: initialize cpu_id_start prior to rseq registration
When adding explicit initialization of rseq fields prior to
registration, I glossed over the fact that 'cpu_id_start' is also
documented as initialized by user-space.
While current kernels don't validate the content of this field on
registration, future ones could.
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
diff --git a/sysdeps/unix/sysv/linux/rseq-internal.h b/sysdeps/unix/sysv/linux/rseq-internal.h
index 7e70ae7ebdee4917..c108a12a6227eeac 100644
--- a/sysdeps/unix/sysv/linux/rseq-internal.h
+++ b/sysdeps/unix/sysv/linux/rseq-internal.h
@@ -56,6 +56,7 @@ rseq_register_current_thread (struct pthread *self, bool do_rseq)
registration, there is no guarantee that struct pthread is
cleared on all architectures. */
THREAD_SETMEM (self, rseq_area.cpu_id, RSEQ_CPU_ID_UNINITIALIZED);
+ THREAD_SETMEM (self, rseq_area.cpu_id_start, 0);
THREAD_SETMEM (self, rseq_area.rseq_cs, 0);
THREAD_SETMEM (self, rseq_area.flags, 0);

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@ -0,0 +1,158 @@
commit c813c1490d5d8640a94fced10fc7674a48737b96
Author: Michael Jeanson <mjeanson@efficios.com>
Date: Wed Jul 10 15:37:28 2024 -0400
nptl: Add rseq auxvals
Get the rseq feature size and alignment requirement from the auxiliary
vector for use inside the dynamic loader. Use '__rseq_size' directly to
store the feature size. If the main thread registration fails or is
disabled by tunable, reset the value to 0.
This will be used in the TLS block allocator to compute the size and
alignment of the rseq area block for the extended ABI support.
Signed-off-by: Michael Jeanson <mjeanson@efficios.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
Conflicts:
sysdeps/nptl/dl-tls_init_tp.c: Adjust for skipped commit:
33237fe83d553dff (Remove --enable-tunables configure option)
diff --git a/sysdeps/nptl/dl-tls_init_tp.c b/sysdeps/nptl/dl-tls_init_tp.c
index 2f56281a02246a09..20552b11843148fb 100644
--- a/sysdeps/nptl/dl-tls_init_tp.c
+++ b/sysdeps/nptl/dl-tls_init_tp.c
@@ -46,6 +46,8 @@ rtld_mutex_dummy (pthread_mutex_t *lock)
const unsigned int __rseq_flags;
+size_t _rseq_align attribute_hidden;
+
void
__tls_pre_init_tp (void)
{
@@ -99,12 +101,17 @@ __tls_init_tp (void)
}
{
+ /* If the registration fails or is disabled by tunable, the public
+ '__rseq_size' will be set to '0' regardless of the feature size of the
+ allocated rseq area. An rseq area of at least 32 bytes is always
+ allocated since application code is allowed to check the status of the
+ rseq registration by reading the content of the 'cpu_id' field. */
bool do_rseq = true;
#if HAVE_TUNABLES
do_rseq = TUNABLE_GET (rseq, int, NULL);
#endif
- if (rseq_register_current_thread (pd, do_rseq))
- _rseq_size = RSEQ_AREA_SIZE_INITIAL_USED;
+ if (!rseq_register_current_thread (pd, do_rseq))
+ _rseq_size = 0;
#ifdef RSEQ_SIG
/* This should be a compile-time constant, but the current
diff --git a/sysdeps/unix/sysv/linux/dl-parse_auxv.h b/sysdeps/unix/sysv/linux/dl-parse_auxv.h
index bf9374371eb217fc..44c135c56570134e 100644
--- a/sysdeps/unix/sysv/linux/dl-parse_auxv.h
+++ b/sysdeps/unix/sysv/linux/dl-parse_auxv.h
@@ -21,6 +21,7 @@
#include <fpu_control.h>
#include <ldsodefs.h>
#include <link.h>
+#include <rseq-internal.h>
typedef ElfW(Addr) dl_parse_auxv_t[AT_MINSIGSTKSZ + 1];
@@ -57,5 +58,17 @@ void _dl_parse_auxv (ElfW(auxv_t) *av, dl_parse_auxv_t auxv_values)
GLRO(dl_sysinfo) = auxv_values[AT_SYSINFO];
#endif
+ /* Get the rseq feature size, with a minimum of RSEQ_AREA_SIZE_INITIAL_USED
+ (20) for kernels that don't have AT_RSEQ_FEATURE_SIZE. Limit the feature
+ size to RSEQ_AREA_SIZE_MAX_USED (28) which fits the rseq area in 'struct
+ pthread' and represents the maximum feature size of currently released
+ kernels. Since no kernels currently cross the 32 bytes of the original
+ ABI, the semantics of a feature size of 32 or more are still undetermined.
+ */
+ _rseq_size = MIN (MAX (auxv_values[AT_RSEQ_FEATURE_SIZE],
+ RSEQ_AREA_SIZE_INITIAL_USED),
+ RSEQ_AREA_SIZE_MAX_USED);
+ _rseq_align = MAX (auxv_values[AT_RSEQ_ALIGN], RSEQ_MIN_ALIGN);
+
DL_PLATFORM_AUXV
}
diff --git a/sysdeps/unix/sysv/linux/rseq-internal.h b/sysdeps/unix/sysv/linux/rseq-internal.h
index c108a12a6227eeac..f4027b09519a652b 100644
--- a/sysdeps/unix/sysv/linux/rseq-internal.h
+++ b/sysdeps/unix/sysv/linux/rseq-internal.h
@@ -25,13 +25,31 @@
#include <stdio.h>
#include <sys/rseq.h>
-/* 32 is the initially required value for the area size. The
- actually used rseq size may be less (20 bytes initially). */
+/* Minimum size of the rseq area allocation required by the syscall. The
+ actually used rseq feature size may be less (20 bytes initially). */
#define RSEQ_AREA_SIZE_INITIAL 32
+
+/* Minimum used feature size of the rseq area. */
#define RSEQ_AREA_SIZE_INITIAL_USED 20
-/* The variables are in .data.relro but are not yet write-protected. */
+/* Maximum currently used feature size of the rseq area. */
+#define RSEQ_AREA_SIZE_MAX_USED 28
+
+/* Minimum alignment of the rseq area. */
+#define RSEQ_MIN_ALIGN 32
+
+/* Alignment requirement of the rseq area.
+ Populated from the auxiliary vector with a minimum of '32'.
+ In .data.relro but not yet write-protected. */
+extern size_t _rseq_align attribute_hidden;
+
+/* Size of the active features in the rseq area.
+ Populated from the auxiliary vector with a minimum of '20'.
+ In .data.relro but not yet write-protected. */
extern unsigned int _rseq_size attribute_hidden;
+
+/* Offset from the thread pointer to the rseq area.
+ In .data.relro but not yet write-protected. */
extern ptrdiff_t _rseq_offset attribute_hidden;
#ifdef RSEQ_SIG
diff --git a/sysdeps/unix/sysv/linux/tst-rseq.c b/sysdeps/unix/sysv/linux/tst-rseq.c
index 1d404db610c08fdf..5946db73d9b079c3 100644
--- a/sysdeps/unix/sysv/linux/tst-rseq.c
+++ b/sysdeps/unix/sysv/linux/tst-rseq.c
@@ -38,13 +38,15 @@ static void
do_rseq_main_test (void)
{
struct pthread *pd = THREAD_SELF;
+ size_t rseq_feature_size = MIN (MAX (getauxval (AT_RSEQ_FEATURE_SIZE),
+ RSEQ_AREA_SIZE_INITIAL_USED),
+ RSEQ_AREA_SIZE_MAX_USED);
TEST_VERIFY_EXIT (rseq_thread_registered ());
TEST_COMPARE (__rseq_flags, 0);
TEST_VERIFY ((char *) __thread_pointer () + __rseq_offset
== (char *) &pd->rseq_area);
- /* The current implementation only supports the initial size. */
- TEST_COMPARE (__rseq_size, 20);
+ TEST_COMPARE (__rseq_size, rseq_feature_size);
}
static void
diff --git a/sysdeps/unix/sysv/linux/tst-rseq.h b/sysdeps/unix/sysv/linux/tst-rseq.h
index a476c316fc2671a0..86cf50fbeff32384 100644
--- a/sysdeps/unix/sysv/linux/tst-rseq.h
+++ b/sysdeps/unix/sysv/linux/tst-rseq.h
@@ -23,6 +23,7 @@
#include <syscall.h>
#include <sys/rseq.h>
#include <tls.h>
+#include <rseq-internal.h>
static inline bool
rseq_thread_registered (void)

11
glibc.spec
View File

@ -157,7 +157,7 @@ end \
Summary: The GNU libc libraries Summary: The GNU libc libraries
Name: glibc Name: glibc
Version: %{glibcversion} Version: %{glibcversion}
Release: 172%{?dist} Release: 173%{?dist}
# In general, GPLv2+ is used by programs, LGPLv2+ is used for # In general, GPLv2+ is used by programs, LGPLv2+ is used for
# libraries. # libraries.
@ -1123,6 +1123,12 @@ Patch815: glibc-RHEL-67593.patch
Patch816: glibc-RHEL-46729.patch Patch816: glibc-RHEL-46729.patch
Patch817: glibc-RHEL-61569-1.patch Patch817: glibc-RHEL-61569-1.patch
Patch818: glibc-RHEL-61569-2.patch Patch818: glibc-RHEL-61569-2.patch
Patch819: glibc-RHEL-65280-1.patch
Patch820: glibc-RHEL-65280-2.patch
Patch821: glibc-RHEL-65280-3.patch
Patch822: glibc-RHEL-65280-4.patch
Patch823: glibc-RHEL-65280-5.patch
Patch824: glibc-RHEL-65280-6.patch
############################################################################## ##############################################################################
# Continued list of core "glibc" package information: # Continued list of core "glibc" package information:
@ -3116,6 +3122,9 @@ update_gconv_modules_cache ()
%endif %endif
%changelog %changelog
* Thu Mar 06 2025 Arjun Shankar <arjun@redhat.com> - 2.34-173
- Make __rseq_size useful for feature detection (RHEL-65280)
* Mon Mar 03 2025 Frederic Berat <fberat@redhat.com> - 2.34-172 * Mon Mar 03 2025 Frederic Berat <fberat@redhat.com> - 2.34-172
- Backport: support: Add support_next_to_fault_before support function - Backport: support: Add support_next_to_fault_before support function
(RHEL-61569) (RHEL-61569)