Sysop: | Amessyroom |
---|---|
Location: | Fayetteville, NC |
Users: | 28 |
Nodes: | 6 (1 / 5) |
Uptime: | 45:07:38 |
Calls: | 422 |
Calls today: | 1 |
Files: | 1,024 |
Messages: | 90,304 |
+ err = __dir_mkfile (dir, O_WRITE, 0777 & ~_hurd_umask, &node);
diff --git a/debian/patches/hurd-i386/git-utime-EINVAL.diff b/debian/patches/hurd-i386/git-utime-EINVAL.diff
new file mode 100644
index 00000000..5fe9d2d8
--- /dev/null
+++ b/debian/patches/hurd-i386/git-utime-EINVAL.diff
@@ -0,0 +1,220 @@
+commit 8a0200c833f261e8eb456bbc4f0f5449e1a5e367
+Author: Samuel Thibault <samuel.thibault@ens-lyon.org>
+Date: Tue Mar 18 18:49:21 2025 +0100
+
+ hurd: Make *utime*s catch invalid times [BZ #32802]
+
+diff --git a/sysdeps/mach/hurd/futimens.c b/sysdeps/mach/hurd/futimens.c +index 30ef0a6493..12125299c4 100644
+--- a/sysdeps/mach/hurd/futimens.c
++++ b/sysdeps/mach/hurd/futimens.c
+@@ -32,7 +32,9 @@ __futimens (int fd, const struct timespec tsp[2])
+ struct timespec atime, mtime;
+ error_t err;
+
+- utime_ts_from_tspec (tsp, &atime, &mtime);
++ err = utime_ts_from_tspec (tsp, &atime, &mtime);
++ if (err)
++ return err;
+
+ err = HURD_DPORT_USE (fd, __file_utimens (port, atime, mtime));
+
+@@ -40,7 +42,9 @@ __futimens (int fd, const struct timespec tsp[2])
+ {
+ time_value_t atim, mtim;
+
+- utime_tvalue_from_tspec (tsp, &atim, &mtim);
++ err = utime_tvalue_from_tspec (tsp, &atim, &mtim);
++ if (err)
++ return err;
+
+ err = HURD_DPORT_USE (fd, __file_utimes (port, atim, mtim));
+ }
+diff --git a/sysdeps/mach/hurd/futimes.c b/sysdeps/mach/hurd/futimes.c +index 20f47f3d28..97385d7dd0 100644
+--- a/sysdeps/mach/hurd/futimes.c
++++ b/sysdeps/mach/hurd/futimes.c
+@@ -32,7 +32,9 @@ __futimes (int fd, const struct timeval tvp[2])
+ struct timespec atime, mtime;
+ error_t err;
+
+- utime_ts_from_tval (tvp, &atime, &mtime);
++ err = utime_ts_from_tval (tvp, &atime, &mtime);
++ if (err)
++ return err;
+
+ err = HURD_DPORT_USE (fd, __file_utimens (port, atime, mtime));
+
+@@ -40,7 +42,9 @@ __futimes (int fd, const struct timeval tvp[2])
+ {
+ time_value_t atim, mtim;
+
+- utime_tvalue_from_tval (tvp, &atim, &mtim);
++ err = utime_tvalue_from_tval (tvp, &atim, &mtim);
++ if (err)
++ return err;
+
+ err = HURD_DPORT_USE (fd, __file_utimes (port, atim, mtim));
+ }
+diff --git a/sysdeps/mach/hurd/utime-helper.c b/sysdeps/mach/hurd/utime-helper.c
+index d88bccd786..6afa871197 100644
+--- a/sysdeps/mach/hurd/utime-helper.c
++++ b/sysdeps/mach/hurd/utime-helper.c
+@@ -21,8 +21,14 @@
+ #include <stddef.h>
+ #include <sys/time.h>
+
++static inline bool
++check_tval (const struct timeval *tvp)
++{
++ return tvp->tv_usec >= 0 && tvp->tv_usec < USEC_PER_SEC;
++}
++
+ /* Initializes atime/mtime timespec structures from an array of timeval. */
+-static inline void
++static inline error_t
+ utime_ts_from_tval (const struct timeval tvp[2],
+ struct timespec *atime, struct timespec *mtime)
+ {
+@@ -37,13 +43,19 @@ utime_ts_from_tval (const struct timeval tvp[2],
+ }
+ else
+ {
++ if (!check_tval (&tvp[0]))
++ return EINVAL;
++ if (!check_tval (&tvp[1]))
++ return EINVAL;
++
+ TIMEVAL_TO_TIMESPEC (&tvp[0], atime);
+ TIMEVAL_TO_TIMESPEC (&tvp[1], mtime);
+ }
++ return 0;
+ }
+
+ /* Initializes atime/mtime time_value_t structures from an array of timeval. */
+-static inline void
++static inline error_t
+ utime_tvalue_from_tval (const struct timeval tvp[2],
+ time_value_t *atime, time_value_t *mtime)
+ {
+@@ -53,11 +65,17 @@ utime_tvalue_from_tval (const struct timeval tvp[2],
+ atime->microseconds = mtime->microseconds = -1;
+ else
+ {
++ if (!check_tval (&tvp[0]))
++ return EINVAL;
++ if (!check_tval (&tvp[1]))
++ return EINVAL;
++
+ atime->seconds = tvp[0].tv_sec;
+ atime->microseconds = tvp[0].tv_usec;
+ mtime->seconds = tvp[1].tv_sec;
+ mtime->microseconds = tvp[1].tv_usec;
+ }
++ return 0;
+ }
+
+ /* Changes the access time of the file behind PORT using a timeval array. */
+@@ -67,7 +85,9 @@ hurd_futimes (const file_t port, const struct timeval tvp[2])
+ error_t err;
+ struct timespec atime, mtime;
+
+- utime_ts_from_tval (tvp, &atime, &mtime);
++ err = utime_ts_from_tval (tvp, &atime, &mtime);
++ if (err)
++ return err;
+
+ err = __file_utimens (port, atime, mtime);
+
+@@ -75,7 +95,9 @@ hurd_futimes (const file_t port, const struct timeval tvp[2])
+ {
+ time_value_t atim, mtim;
+
+- utime_tvalue_from_tval (tvp, &atim, &mtim);
++ err = utime_tvalue_from_tval (tvp, &atim, &mtim);
++ if (err)
++ return err;
+
+ err = __file_utimes (port, atim, mtim);
+ }
+@@ -83,8 +105,16 @@ hurd_futimes (const file_t port, const struct timeval tvp[2])
+ return err;
+ }
+
++static inline bool
++check_tspec (const struct timespec *tsp)
++{
++ return tsp->tv_nsec == UTIME_NOW
++ || tsp->tv_nsec == UTIME_OMIT
++ || tsp->tv_nsec >= 0 && tsp->tv_nsec < NSEC_PER_SEC;
++}
++
+ /* Initializes atime/mtime timespec structures from an array of timespec. */
+-static inline void
++static inline error_t
+ utime_ts_from_tspec (const struct timespec tsp[2],
+ struct timespec *atime, struct timespec *mtime)
+ {
+@@ -99,13 +129,19 @@ utime_ts_from_tspec (const struct timespec tsp[2],
+ }
+ else
+ {
++ if (!check_tspec (&tsp[0]))
++ return EINVAL;
++ if (!check_tspec (&tsp[1]))
++ return EINVAL;
++
+ *atime = tsp[0];
+ *mtime = tsp[1];
+ }
++ return 0;
+ }
+
+ /* Initializes atime/mtime time_value_t structures from an array of timespec. */
+-static inline void
++static inline error_t
+ utime_tvalue_from_tspec (const struct timespec tsp[2],
+ time_value_t *atime, time_value_t *mtime)
+ {
+@@ -115,6 +151,11 @@ utime_tvalue_from_tspec (const struct timespec tsp[2], + atime->microseconds = mtime->microseconds = -1;
+ else
+ {
++ if (!check_tspec (&tsp[0]))
++ return EINVAL;
++ if (!check_tspec (&tsp[1]))
++ return EINVAL;
++
+ if (tsp[0].tv_nsec == UTIME_NOW)
+ atime->microseconds = -1;
+ else if (tsp[0].tv_nsec == UTIME_OMIT)
+@@ -128,6 +169,7 @@ utime_tvalue_from_tspec (const struct timespec tsp[2],
+ else
+ TIMESPEC_TO_TIME_VALUE (mtime, &(tsp[1]));
+ }
++ return 0;
+ }
+
+ /* Changes the access time of the file behind PORT using a timespec array. */
+@@ -137,7 +179,9 @@ hurd_futimens (const file_t port, const struct timespec tsp[2])
+ error_t err;
+ struct timespec atime, mtime;
+
+- utime_ts_from_tspec (tsp, &atime, &mtime);
++ err = utime_ts_from_tspec (tsp, &atime, &mtime);
++ if (err)
++ return err;
+
+ err = __file_utimens (port, atime, mtime);
+
+@@ -145,7 +189,9 @@ hurd_futimens (const file_t port, const struct timespec tsp[2])
+ {
+ time_value_t atim, mtim;
+
+- utime_tvalue_from_tspec (tsp, &atim, &mtim);
++ err = utime_tvalue_from_tspec (tsp, &atim, &mtim);
++ if (err)
++ return err;
+
+ err = __file_utimes (port, atim, mtim);
+ }
diff --git a/debian/patches/hurd-i386/git-xstate-initialized.diff b/debian/patches/hurd-i386/git-xstate-initialized.diff
new file mode 100644
index 00000000..65f6d31d
--- /dev/null
+++ b/debian/patches/hurd-i386/git-xstate-initialized.diff
@@ -0,0 +1,108 @@
+commit 8d54b428cfe98c21049f94c8af3bf302e44091e9
+Author: Samuel Thibault <samuel.thibault@ens-lyon.org>
+Date: Mon Apr 21 19:42:27 2025 +0200
+
+ hurd: Do not restore xstate when it is not initialized
+
+ If the process has never used fp before getting a signal, xstate is set + (and thus the x87 state is not initialized) but xstate->initialized is still
+ 0, and we should not restore anything.
+
+diff --git a/sysdeps/mach/hurd/i386/sigreturn.c b/sysdeps/mach/hurd/i386/sigreturn.c
+index 37fa984070..dc57d6122c 100644
+--- a/sysdeps/mach/hurd/i386/sigreturn.c
++++ b/sysdeps/mach/hurd/i386/sigreturn.c
+@@ -126,24 +126,27 @@ __sigreturn (struct sigcontext *scp)
+ ss->sigaltstack.ss_flags &= ~SS_ONSTACK;
+
+ #ifdef i386_XFLOAT_STATE
+- if ((scp->xstate) && (scp->xstate->initialized))
++ if (scp->xstate)
+ {
+- unsigned eax, ebx, ecx, edx;
+- __cpuid_count(0xd, 0, eax, ebx, ecx, edx);
+- switch (scp->xstate->fp_save_kind)
+- {
+- case 0: // FNSAVE
+- asm volatile("frstor %0" : : "m" (scp->xstate->hw_state));
+- break;
+- case 1: // FXSAVE
+- asm volatile("fxrstor %0" : : "m" (scp->xstate->hw_state), \ +- "a" (eax), "d" (edx));
+- break;
+- default: // XSAVE, XSAVEOPT, XSAVEC, XSAVES
+- asm volatile("xrstor %0" : : "m" (scp->xstate->hw_state), \ +- "a" (eax), "d" (edx));
+- break;
+- }
++ if (scp->xstate->initialized)
++ {
++ unsigned eax, ebx, ecx, edx;
++ __cpuid_count(0xd, 0, eax, ebx, ecx, edx);
++ switch (scp->xstate->fp_save_kind)
++ {
++ case 0: // FNSAVE
++ asm volatile("frstor %0" : : "m" (scp->xstate->hw_state));
++ break;
++ case 1: // FXSAVE
++ asm volatile("fxrstor %0" : : "m" (scp->xstate->hw_state), \ ++ "a" (eax), "d" (edx));
++ break;
++ default: // XSAVE, XSAVEOPT, XSAVEC, XSAVES
++ asm volatile("xrstor %0" : : "m" (scp->xstate->hw_state), \ ++ "a" (eax), "d" (edx));
++ break;
++ }
++ }
+ }
+ else
+ #endif
+diff --git a/sysdeps/mach/hurd/x86_64/sigreturn.c b/sysdeps/mach/hurd/x86_64/sigreturn.c
+index dff8e76dc8..773c00f86d 100644
+--- a/sysdeps/mach/hurd/x86_64/sigreturn.c
++++ b/sysdeps/mach/hurd/x86_64/sigreturn.c
+@@ -119,24 +119,27 @@ __sigreturn (struct sigcontext *scp)
+ ss->sigaltstack.ss_flags &= ~SS_ONSTACK;
+
+ #ifdef i386_XFLOAT_STATE
+- if ((scp->xstate) && (scp->xstate->initialized))
++ if (scp->xstate)
+ {
+- unsigned eax, ebx, ecx, edx;
+- __cpuid_count(0xd, 0, eax, ebx, ecx, edx);
+- switch (scp->xstate->fp_save_kind)
+- {
+- case 0: // FNSAVE
+- asm volatile("frstor %0" : : "m" (scp->xstate->hw_state));
+- break;
+- case 1: // FXSAVE
+- asm volatile("fxrstor %0" : : "m" (scp->xstate->hw_state), \ +- "a" (eax), "d" (edx));
+- break;
+- default: // XSAVE, XSAVEOPT, XSAVEC, XSAVES
+- asm volatile("xrstor %0" : : "m" (scp->xstate->hw_state), \ +- "a" (eax), "d" (edx));
+- break;
+- }
++ if (scp->xstate->initialized)
++ {
++ unsigned eax, ebx, ecx, edx;
++ __cpuid_count(0xd, 0, eax, ebx, ecx, edx);
++ switch (scp->xstate->fp_save_kind)
++ {
++ case 0: // FNSAVE
++ asm volatile("frstor %0" : : "m" (scp->xstate->hw_state));
++ break;
++ case 1: // FXSAVE
++ asm volatile("fxrstor %0" : : "m" (scp->xstate->hw_state), \ ++ "a" (eax), "d" (edx));
++ break;
++ default: // XSAVE, XSAVEOPT, XSAVEC, XSAVES
++ asm volatile("xrstor %0" : : "m" (scp->xstate->hw_state), \ ++ "a" (eax), "d" (edx));
++ break;
++ }
++ }
+ }
+ else
+ #endif
diff --git a/debian/patches/hurd-i386/git-xstate.diff b/debian/patches/hurd-i386/git-xstate.diff
new file mode 100644
index 00000000..d2caa989
--- /dev/null
+++ b/debian/patches/hurd-i386/git-xstate.diff
@@ -0,0 +1,648 @@
+commit 6d6a6e2dd2133908e3f5cb8a2ed817ccb2a0bb06
+Author: Luca Dariz <luca@orpolo.org>
+Date: Wed Mar 19 18:11:18 2025 +0100
+
+ hurd: save xstate during signal handling
+
+ * hurd/Makefile: add new tests
+ * hurd/test-sig-rpc-interrupted.c: check xstate save and restore in
+ the case where a signal is delivered to a thread which is waiting
+ for an rpc. This test implements the rpc interruption protocol used
+ by the hurd servers. It was so far passing on Debian thanks to the
+ local-intr-msg-clobber.diff patch, which is now obsolete.
+ * hurd/test-sig-xstate.c: check xstate save and restore in the case
+ where a signal is delivered to a running thread, making sure that
+ the xstate is modified in the signal handler.
+ * hurd/test-xstate.h: add helpers to test xstate
+ * sysdeps/mach/hurd/i386/bits/sigcontext.h: add xstate to the
+ sigcontext structure.
+ + sysdeps/mach/hurd/i386/sigreturn.c: restore xstate from the saved
+ context
+ * sysdeps/mach/hurd/x86/trampoline.c: save xstate if
+ supported. Otherwise we fall back to the previous behaviour of
+ ignoring xstate.
+ * sysdeps/mach/hurd/x86_64/bits/sigcontext.h: add xstate to the
+ sigcontext structure.
+ * sysdeps/mach/hurd/x86_64/sigreturn.c: restore xstate from the saved
+ context
+
+ Signed-off-by: Luca Dariz <luca@orpolo.org>
+ Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
+ Message-ID: <20250319171118.142163-1-luca@orpolo.org>
+
+diff --git a/hurd/Makefile b/hurd/Makefile
+index cf70b8c65c..cbc3c23b1f 100644
+--- a/hurd/Makefile
++++ b/hurd/Makefile
+@@ -19,6 +19,11 @@ subdir := hurd
+
+ include ../Makeconfig
+
++tests := test-sig-xstate \
++ test-sig-rpc-interrupted
++$(objpfx)test-sig-xstate: $(shared-thread-library) ++$(objpfx)test-sig-rpc-interrupted: $(shared-thread-library) $(objdir)/hurd/libhurduser.so
++
+ headers = \
+ $(interface-headers) \
+ hurd.h \
+diff --git a/hurd/test-sig-rpc-interrupted.c b/hurd/test-sig-rpc-interrupted.c
+new file mode 100644
+index 0000000000..a89d70e5a4
+--- /dev/null
++++ b/hurd/test-sig-rpc-interrupted.c
+@@ -0,0 +1,185 @@
++/* Test the state save/restore procedures during signal handling when an
++ interruptible RPC is restarted.
++
++ 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 <assert.h>
++#include <pthread.h>
++#include <signal.h>
++#include <stdbool.h>
++#include <stdio.h>
++#include <stdlib.h>
++#include <string.h>
++#include <unistd.h>
++
++#include <mach/message.h>
++#include <mach/gnumach.h>
++#include <mach/mach_traps.h>
++#include <mach/mig_errors.h>
++#include <mach-shortcuts.h>
++#include <mach_init.h>
++#include <hurd/io.h>
++#include <hurd/io_reply.h>
++
++#include <support/check.h>
++#include <support/xthread.h>
++
++#include "test-xstate.h"
++
++void handler (int signum, siginfo_t *info, void *context)
++{
++ printf ("signal %d setting a different CPU state\n", signum);
++ char buf3[XSTATE_BUFFER_SIZE];
++ memset (buf3, 0x77, XSTATE_BUFFER_SIZE);
++ SET_XSTATE (buf3);
++}
++
++static const mach_msg_type_t RetCodeCheck = {
++ .msgt_name = (unsigned char) MACH_MSG_TYPE_INTEGER_32,
++ .msgt_size = 32,
++ .msgt_number = 1,
++ .msgt_inline = TRUE,
++ .msgt_longform = FALSE,
++ .msgt_deallocate = FALSE,
++ .msgt_unused = 0
++};
++
++
++/* Helper thread to simulate a proper RPC interruption during dignal handling */
++void* fake_interruptor (void *arg)
++{
++ int err;
++ sigset_t ss;
++ TEST_COMPARE (sigemptyset (&ss), 0);
++ TEST_COMPARE (sigaddset (&ss, SIGUSR1), 0);
++ TEST_COMPARE (sigprocmask (SIG_BLOCK, &ss, NULL), 0);
++
++ struct {
++ mach_msg_header_t Head;
++ } request;
++ mach_port_t rxport = *((mach_port_t*)arg);
++ err = mach_msg (&request.Head, MACH_RCV_MSG, 0, sizeof (request), rxport, ++ MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
++ TEST_COMPARE (err, MACH_MSG_SUCCESS);
++ TEST_COMPARE (request.Head.msgh_bits, 0x1112);
++ TEST_COMPARE (request.Head.msgh_size, sizeof (request.Head));
++ TEST_COMPARE (request.Head.msgh_id, 33000);
++
++ mig_reply_header_t reply;
++ reply.Head = request.Head;
++ reply.Head.msgh_id += 100;
++ reply.RetCodeType = RetCodeCheck;
++ reply.RetCode = KERN_SUCCESS;
++ err = mach_msg (&reply.Head, MACH_SEND_MSG, sizeof (reply), 0, MACH_PORT_NULL,
++ MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
++ TEST_COMPARE (err, MACH_MSG_SUCCESS);
++
++ return NULL;
++}
++
++
++/* Helper thread to send a signal to the main thread in the middle of
++ * an interruptible rpc */
++void* signal_sender (void *arg)
++{
++ int err;
++ sigset_t ss;
++ TEST_COMPARE (sigemptyset (&ss), 0);
++ TEST_COMPARE (sigaddset (&ss, SIGUSR1), 0);
++ TEST_COMPARE (sigprocmask (SIG_BLOCK, &ss, NULL), 0);
++
++ /* Receive the first request, we won't answer to this. */
++ struct {
++ mach_msg_header_t head;
++ char data[64];
++ } m1, m2;
++ mach_port_t rxport = *((mach_port_t*)arg);
++ memset (&m1, 0, sizeof (m1));
++ memset (&m2, 0, sizeof (m2));
++ err = mach_msg (&m1.head, MACH_RCV_MSG, 0, sizeof (m1), rxport,
++ MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
++ TEST_COMPARE (err, MACH_MSG_SUCCESS);
++
++ /* interrupt the ongoing rpc with a signal, using the
++ * interruptible rpc protocol */
++ pthread_t thintr = xpthread_create (NULL, fake_interruptor, arg);
++ TEST_COMPARE (kill (getpid (), SIGUSR1), 0);
++ xpthread_join (thintr);
++
++ /* Complete the interruption by sending EINTR */
++ mig_reply_header_t reply;
++ reply.Head = m1.head;
++ reply.Head.msgh_id += 100;
++ reply.RetCodeType = RetCodeCheck;
++ reply.RetCode = EINTR;
++ err = mach_msg (&reply.Head, MACH_SEND_MSG, sizeof (reply), 0, MACH_PORT_NULL,
++ MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
++ TEST_COMPARE (err, MACH_MSG_SUCCESS);
++
++ /* Receive the retried rpc, and check that it has the same payload
++ * as the first one. Port names might still be different. */
++ err = mach_msg (&m2.head, MACH_RCV_MSG, 0, sizeof (m2), rxport,
++ MACH_MSG_TIMEOUT_NONE, MACH_PORT_NULL);
++ TEST_COMPARE (m1.head.msgh_bits, m2.head.msgh_bits);
++ TEST_COMPARE (m1.head.msgh_size, m2.head.msgh_size);
++ TEST_COMPARE (m1.head.msgh_id, m2.head.msgh_id);
++ TEST_COMPARE_BLOB (m1.data, sizeof (m1.data), m2.data, sizeof (m2.data)); ++
++ /* And finally make the rpc succeed by sending a valid reply */
++ err = io_read_reply (m2.head.msgh_remote_port, MACH_MSG_TYPE_MOVE_SEND_ONCE,
++ KERN_SUCCESS, NULL, 0);
++ TEST_COMPARE (err, MACH_MSG_SUCCESS);
++
++ return NULL;
++}
++
++
++static int do_test (void)
++{
++#if ! XSTATE_HELPERS_SUPPORTED
++ FAIL_UNSUPPORTED ("Test not supported on this arch.");
++#endif
++
++ /* Setup signal handling; we need to handle the signal in the main
++ * thread, the other ones will explicitely block SIGUSR1. */
++ struct sigaction act = { 0 };
++ act.sa_flags = SA_RESTART;
++ act.sa_sigaction = &handler;
++ TEST_COMPARE (sigaction (SIGUSR1, &act, NULL), 0);
++
++ mach_port_t fakeio;
++ int err;
++ err = mach_port_allocate (mach_task_self (), MACH_PORT_RIGHT_RECEIVE, &fakeio);
++ TEST_COMPARE (err, MACH_MSG_SUCCESS);
++
++ err = mach_port_insert_right (mach_task_self (), fakeio, fakeio,
++ MACH_MSG_TYPE_MAKE_SEND);
++ TEST_COMPARE (err, MACH_MSG_SUCCESS);
++
++ pthread_t thsender = xpthread_create (NULL, signal_sender, &fakeio);
++
++ char *buf;
++ mach_msg_type_number_t n;
++ TEST_COMPARE (io_read (fakeio, &buf, &n, 1, 2), 0);
++
++ xpthread_join (thsender);
++ return EXIT_SUCCESS;
++}
++
++#include <support/test-driver.c>
+diff --git a/hurd/test-sig-xstate.c b/hurd/test-sig-xstate.c
+new file mode 100644
+index 0000000000..0a68a44fd7
+--- /dev/null
++++ b/hurd/test-sig-xstate.c
+@@ -0,0 +1,94 @@
++/* Test the state save/restore procedures during signal handling.
++
++ Copyright (C) 2025 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 <assert.h>
++#include <pthread.h>
++#include <signal.h>
++#include <stdbool.h>
++#include <stdio.h>
++#include <stdlib.h>
++#include <string.h>
++#include <unistd.h>
++
++#include <mach/message.h>
++#include <mach/gnumach.h>
++#include <mach/mach_traps.h>
++#include <mach-shortcuts.h>
++#include <mach_init.h>
++#include <hurd/io.h>
++#include <hurd/io_reply.h>
++
++#include <support/check.h>
++#include <support/xthread.h>
++
++#include "test-xstate.h"
++
++static volatile bool loopflag = true;
++
++void handler (int signum, siginfo_t *info, void *context)
++{
++ char buf3[XSTATE_BUFFER_SIZE];
++ memset (buf3, 0x77, XSTATE_BUFFER_SIZE);
++ SET_XSTATE (buf3);
++ printf ("signal %d setting a different CPU state\n", signum);
++ loopflag = false;
++}
++
++/* Helper thread to send a signal to the main thread */
++void* signal_sender (void *arg)
++{
++ sigset_t ss;
++ assert (! sigemptyset (&ss));
++ assert (! sigaddset (&ss, SIGUSR1));
++ assert (! sigprocmask (SIG_BLOCK, &ss, NULL));
++
++ TEST_COMPARE (kill (getpid (), SIGUSR1), 0);
++
++ return NULL;
++}
++
++static int do_test (void)
++{
++#if ! XSTATE_HELPERS_SUPPORTED
++ FAIL_UNSUPPORTED ("Test not supported on this arch.");
++#endif
++
++ struct sigaction act = { 0 };
++ act.sa_sigaction = &handler;
++ TEST_COMPARE (sigaction (SIGUSR1, &act, NULL), 0);
++
++ pthread_t thsender = xpthread_create (NULL, signal_sender, NULL);
++
++ char buf1[XSTATE_BUFFER_SIZE], buf2[XSTATE_BUFFER_SIZE];
++ memset (buf1, 0x33, XSTATE_BUFFER_SIZE);
++
++ SET_XSTATE (buf1);
++
++ while (loopflag)
++ ;
++
++ GET_XSTATE (buf2);
++ TEST_COMPARE_BLOB (buf1, sizeof (buf1), buf2, sizeof (buf2));
++
++ xpthread_join (thsender);
++ return EXIT_SUCCESS;
++}
++
++#include <support/test-driver.c>
+diff --git a/hurd/test-xstate.h b/hurd/test-xstate.h
+new file mode 100644
+index 0000000000..a8185dcb07
+--- /dev/null
++++ b/hurd/test-xstate.h
+@@ -0,0 +1,40 @@
++/* Helpers to test XSTATE during signal handling
++
++ Copyright (C) 2025 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/>. */
++
++#ifndef _TEST_XSTATE_H
++#define _TEST_XSTATE_H
++
++#if defined __x86_64__ || defined __i386__
++#define XSTATE_HELPERS_SUPPORTED 1
++#define XSTATE_BUFFER_SIZE 16
++#define SET_XSTATE(b) do { \
++ asm volatile ("movups (%0),%%xmm0" :: "r" (b)); \
++ } while (0)
++
++#define GET_XSTATE(b) do { \
++ asm volatile ("movups %%xmm0,(%0)" :: "r" (b)); \
++ } while (0)
++
++#else
++#define XSTATE_HELPERS_SUPPORTED 0
++#define XSTATE_BUFFER_SIZE 1
++#define SET_XSTATE(b)
++#endif
++
++#endif /* _TEST_XSTATE_H */
+diff --git a/sysdeps/mach/hurd/i386/bits/sigcontext.h b/sysdeps/mach/hurd/i386/bits/sigcontext.h
+index 6e5e220e9d..c44e4deac6 100644
+--- a/sysdeps/mach/hurd/i386/bits/sigcontext.h
++++ b/sysdeps/mach/hurd/i386/bits/sigcontext.h
+@@ -88,6 +88,8 @@ struct sigcontext
+ struct i386_fp_save sc_fpsave;
+ struct i386_fp_regs sc_fpregs;
+ int sc_fpexcsr; /* FPSR including exception bits. */
++
++ struct i386_xfloat_state *xstate;
+ };
+
+ /* Traditional BSD names for some members. */
+diff --git a/sysdeps/mach/hurd/i386/sigreturn.c b/sysdeps/mach/hurd/i386/sigreturn.c
+index ce8df8d02b..37fa984070 100644
+--- a/sysdeps/mach/hurd/i386/sigreturn.c
++++ b/sysdeps/mach/hurd/i386/sigreturn.c
+@@ -21,6 +21,8 @@
+ #include <stdlib.h>
+ #include <string.h>
+
++#include <cpuid.h>
++
+ /* This is run on the thread stack after restoring it, to be able to
+ unlock SS off sigstack. */
+ static void
+@@ -123,10 +125,32 @@ __sigreturn (struct sigcontext *scp)
+ if (scp->sc_onstack)
+ ss->sigaltstack.ss_flags &= ~SS_ONSTACK;
+
+- if (scp->sc_fpused)
+- /* Restore the FPU state. Mach conveniently stores the state
+- in the format the i387 `frstor' instruction uses to restore it. */ +- asm volatile ("frstor %0" : : "m" (scp->sc_fpsave));
++#ifdef i386_XFLOAT_STATE
++ if ((scp->xstate) && (scp->xstate->initialized))
++ {
++ unsigned eax, ebx, ecx, edx;
++ __cpuid_count(0xd, 0, eax, ebx, ecx, edx);
++ switch (scp->xstate->fp_save_kind)
++ {
++ case 0: // FNSAVE
++ asm volatile("frstor %0" : : "m" (scp->xstate->hw_state));
++ break;
++ case 1: // FXSAVE
++ asm volatile("fxrstor %0" : : "m" (scp->xstate->hw_state), \ ++ "a" (eax), "d" (edx));
++ break;
++ default: // XSAVE, XSAVEOPT, XSAVEC, XSAVES
++ asm volatile("xrstor %0" : : "m" (scp->xstate->hw_state), \ ++ "a" (eax), "d" (edx));
++ break;
++ }
++ }
++ else
++#endif
++ if (scp->sc_fpused)
++ /* Restore the FPU state. Mach conveniently stores the state
++ in the format the i387 `frstor' instruction uses to restore it. */
++ asm volatile ("frstor %0" : : "m" (scp->sc_fpsave));
+
+ {
+ /* There are convenient instructions to pop state off the stack, so we +diff --git a/sysdeps/mach/hurd/x86/trampoline.c b/sysdeps/mach/hurd/x86/trampoline.c
+index 8e2890f8c5..db756e8a1f 100644
+--- a/sysdeps/mach/hurd/x86/trampoline.c
++++ b/sysdeps/mach/hurd/x86/trampoline.c
+@@ -26,7 +26,11 @@
+ #include "hurdfault.h"
+ #include <intr-msg.h>
+ #include <sys/ucontext.h>
+-
++#ifdef __x86_64__
++#include <mach/x86_64/mach_i386.h>
++#else
++#include <mach/i386/mach_i386.h>
++#endif
+
+ /* Fill in a siginfo_t structure for SA_SIGINFO-enabled handlers. */
+ static void fill_siginfo (siginfo_t *si, int signo,
+@@ -106,6 +110,7 @@ _hurd_setup_sighandler (struct hurd_sigstate *ss, const struct sigaction *action
+ void firewall (void);
+ void *sigsp;
+ struct sigcontext *scp;
++ vm_size_t xstate_size;
+ struct
+ {
+ union
+@@ -145,6 +150,14 @@ _hurd_setup_sighandler (struct hurd_sigstate *ss, const struct sigaction *action
+ struct hurd_userlink link;
+ ucontext_t ucontext;
+ siginfo_t siginfo;
++#ifdef __x86_64__
++ char _pad2[56];
++#else
++ char _pad2[20];
++#endif
++ char xstate[];
++ /* Don't add anything after xstate, as it's dynamically
++ sized. */
+ } *stackframe;
+
+ #ifdef __x86_64__
+@@ -170,6 +183,17 @@ _hurd_setup_sighandler (struct hurd_sigstate *ss, const struct sigaction *action
+ if (! machine_get_basic_state (ss->thread, state))
+ return NULL;
+
++ /* Initialize the size of the CPU extended state, to be saved during
++ * signal handling */
++#ifdef i386_XFLOAT_STATE
++ _Static_assert ((sizeof(*stackframe) + sizeof(struct i386_xfloat_state)) % 64 == 0,
++ "stackframe size must be multiple of 64-byte minus "
++ "sizeof(struct i386_xfloat_state), please adjust _pad2"); ++
++ if (__i386_get_xstate_size(__mach_host_self(), &xstate_size))
++#endif
++ xstate_size = 0;
++
+ /* Save the original SP in the gratuitous `esp' slot.
+ We may need to reset the SP (the `uesp' slot) to avoid clobbering an
+ interrupted RPC frame. */
+@@ -196,14 +220,21 @@ _hurd_setup_sighandler (struct hurd_sigstate *ss, const struct sigaction *action
+ #endif
+ }
+
+- /* Push the arguments to call `trampoline' on the stack. */
+- sigsp -= sizeof (*stackframe);
+-#ifdef __x86_64__
+- /* Align SP at 16 bytes. Coupled with the fact that sigreturn_addr is
+- 16-byte aligned within the stackframe struct, this ensures that it ends
+- up on a 16-byte aligned address, as required by the ABI. */
+- sigsp = (void *) ((uintptr_t) sigsp & ~15UL);
+-#endif
++ /* Push the arguments to call `trampoline' on the stack.
++ * The extended state might have a variable size depending on the platform,
++ * so we dynamically allocate it on the stack frame.*/
++ sigsp -= sizeof (*stackframe) + xstate_size;
++
++ /* Align SP at 64 bytes. This is needed for two reasons:
++ * - sigreturn_addr is 16-byte aligned within the stackframe
++ * struct, and this ensures that it ends up on a 16-byte aligned
++ * address, as required by the ABI.
++ * - the XSAVE state needs to be aligned at 64 bytes (on both i386 and
++ * x86_64), so we align the stackframe also at 64 bytes and add the
++ * required padding at the end, see the _pad2 field.
++ */
++ sigsp = (void *) ((uintptr_t) sigsp & ~63UL);
++
+ stackframe = sigsp;
+
+ if (_hurdsig_catch_memory_fault (stackframe))
+@@ -248,14 +279,40 @@ _hurd_setup_sighandler (struct hurd_sigstate *ss, const struct sigaction *action
+ memcpy (&scp->sc_i386_thread_state,