glibc/sysdeps/mach/htl/pt-stack-alloc.c
Sergey Bugaev a4273efa21 htl: Respect GL(dl_stack_flags) when allocating stacks
Previously, HTL would always allocate non-executable stacks.  This has
never been noticed, since GNU Mach on x86 ignores VM_PROT_EXECUTE and
makes all pages implicitly executable.  Since GNU Mach on AArch64
supports non-executable pages, HTL forgetting to pass VM_PROT_EXECUTE
immediately breaks any code that (unfortunately, still) relies on
executable stacks.

Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-ID: <20240323173301.151066-7-bugaevc@gmail.com>
2024-03-23 22:48:44 +01:00

47 lines
1.6 KiB
C

/* Allocate a new stack. Mach version.
Copyright (C) 2000-2024 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 <errno.h>
#include <mach.h>
#include <pt-internal.h>
/* Allocate a new stack of size STACKSIZE. If successful, store the
address of the newly allocated stack in *STACKADDR and return 0.
Otherwise return an error code (EINVAL for an invalid stack size,
EAGAIN if the system lacked the necessary resources to allocate a
new stack). */
int
__pthread_stack_alloc (void **stackaddr, size_t stacksize)
{
error_t err;
vm_prot_t prot = VM_PROT_READ | VM_PROT_WRITE;
if (GL(dl_stack_flags) & PF_X)
prot |= VM_PROT_EXECUTE;
err = __vm_map (__mach_task_self (), (vm_offset_t *) stackaddr,
stacksize, 0, TRUE, MEMORY_OBJECT_NULL, 0, FALSE,
prot, VM_PROT_ALL, VM_INHERIT_COPY);
if (err == KERN_NO_SPACE)
err = EAGAIN;
return err;
}