[PATCH] elf: early conversion of elf p_flags to mprotect flags
Cupertino Miranda
cupertino.miranda@oracle.com
Thu Jun 12 07:05:00 GMT 2025
Thanks !
On 11-06-2025 17:16, Adhemerval Zanella Netto wrote:
> Hi Cupertino,
>
> This, along with the MVE ABI proposal, is on my backlog list and I hope
> to review/reply this week.
>
> On 11/06/25 12:34, Cupertino Miranda wrote:
>> PING.
>>
>> On 04-06-2025 16:58, Cupertino Miranda wrote:
>>> PING! :)
>>>
>>> On 14-05-2025 16:18, Cupertino Miranda wrote:
>>>> Hi everyone,
>>>>
>>>> This patch is related to a change requested by Florian in respect to
>>>> adding support for MTE stack mode, to which stacks in general needed to
>>>> be protected with PROT_MTE.
>>>>
>>>> Both the files dl-mmap-prot.[ch] and the function name __pf_to_prot,
>>>> should likely be renamed. Please advise.
>>>>
>>>> No regressions for x86-64.
>>>>
>>>> Looking forward to your comments.
>>>>
>>>> Cheers,
>>>> Cupertino
>>>>
>>>> This patch replaces _dl_stack_flags global variable by
>>>> _dl_stack_prot_flags.
>>>> The advantage is that any convertion from p_flags to final used mprotect
>>>> flags occurs at loading of p_flags. It avoids repeated spurious
>>>> convertions of _dl_stack_flags, for example in allocate_thread_stack.
>>>>
>>>> This modification was suggested in:
>>>> https://sourceware.org/pipermail/libc-alpha/2025-March/165537.html
>>>> ---
>>>> elf/Makefile | 4 ++-
>>>> elf/dl-execstack-tunable.c | 2 +-
>>>> elf/dl-load.c | 20 ++++---------
>>>> elf/dl-mmap-prot.c | 41 ++++++++++++++++++++++++++
>>>> elf/dl-mmap-prot.h | 26 ++++++++++++++++
>>>> elf/dl-support.c | 7 ++---
>>>> elf/rtld.c | 5 +++-
>>>> nptl/allocatestack.c | 12 ++------
>>>> support/support_stack_alloc.c | 9 +++---
>>>> sysdeps/alpha/stackinfo.h | 6 ++--
>>>> sysdeps/arm/stackinfo.h | 6 ++--
>>>> sysdeps/generic/ldsodefs.h | 1 +
>>>> sysdeps/generic/stackinfo.h | 2 +-
>>>> sysdeps/hppa/stackinfo.h | 6 ++--
>>>> sysdeps/i386/stackinfo.h | 6 ++--
>>>> sysdeps/m68k/stackinfo.h | 6 ++--
>>>> sysdeps/mach/htl/pt-stack-alloc.c | 2 +-
>>>> sysdeps/mach/hurd/dl-execstack.c | 2 +-
>>>> sysdeps/microblaze/stackinfo.h | 6 ++--
>>>> sysdeps/mips/stackinfo.h | 6 ++--
>>>> sysdeps/or1k/stackinfo.h | 6 ++--
>>>> sysdeps/powerpc/powerpc32/stackinfo.h | 4 +--
>>>> sysdeps/s390/stackinfo.h | 6 ++--
>>>> sysdeps/sh/stackinfo.h | 6 ++--
>>>> sysdeps/sparc/stackinfo.h | 6 ++--
>>>> sysdeps/unix/sysv/linux/dl-execstack.c | 2 +-
>>>> sysdeps/unix/sysv/linux/spawni.c | 5 +---
>>>> sysdeps/x86_64/stackinfo.h | 6 ++--
>>>> 28 files changed, 133 insertions(+), 83 deletions(-)
>>>> create mode 100644 elf/dl-mmap-prot.c
>>>> create mode 100644 elf/dl-mmap-prot.h
>>>>
>>>> diff --git a/elf/Makefile b/elf/Makefile
>>>> index ed1b0223da..a2e592b50f 100644
>>>> --- a/elf/Makefile
>>>> +++ b/elf/Makefile
>>>> @@ -69,6 +69,7 @@ dl-routines = \
>>>> dl-lookup-direct \
>>>> dl-minimal-malloc \
>>>> dl-misc \
>>>> + dl-mmap-prot \
>>>> dl-object \
>>>> dl-open \
>>>> dl-origin \
>>>> @@ -139,6 +140,7 @@ rtld-routines = \
>>>> dl-hwcaps_split \
>>>> dl-libc_freeres \
>>>> dl-minimal \
>>>> + dl-mmap-prot \
>>>> dl-mutex \
>>>> dl-profile \
>>>> dl-sysdep \
>>>> @@ -2154,7 +2156,7 @@ $(objpfx)execstack-default: $(first-word $(wildcard $(sysdirs:%=%/stackinfo.h)))
>>>> $(make-target-directory)
>>>> { echo '#include <elf.h>'; \
>>>> echo '#include <stackinfo.h>'; \
>>>> - echo '#if (DEFAULT_STACK_PERMS & PF_X) == 0'; \
>>>> + echo '#if (DEFAULT_STACK_PROT_PERMS & PROT_EXEC) == 0'; \
>>>> echo '@@@execstack-no@@@'; \
>>>> echo '#else'; \
>>>> echo '@@@execstack-yes@@@'; \
>>>> diff --git a/elf/dl-execstack-tunable.c b/elf/dl-execstack-tunable.c
>>>> index e3b638aeaa..b2511ea031 100644
>>>> --- a/elf/dl-execstack-tunable.c
>>>> +++ b/elf/dl-execstack-tunable.c
>>>> @@ -25,7 +25,7 @@ _dl_handle_execstack_tunable (void)
>>>> switch (TUNABLE_GET (glibc, rtld, execstack, int32_t, NULL))
>>>> {
>>>> case stack_tunable_mode_disable:
>>>> - if ((__glibc_unlikely (GL(dl_stack_flags)) & PF_X))
>>>> + if ((__glibc_unlikely (GL(dl_stack_prot_flags)) & PROT_EXEC))
>>>> _dl_fatal_printf (
>>>> "Fatal glibc error: executable stack is not allowed\n");
>>>> break;
>>>> diff --git a/elf/dl-load.c b/elf/dl-load.c
>>>> index bf29ec725d..6aae07b9f0 100644
>>>> --- a/elf/dl-load.c
>>>> +++ b/elf/dl-load.c
>>>> @@ -74,6 +74,7 @@ struct filebuf
>>>> #include <dl-unmap-segments.h>
>>>> #include <dl-machine-reject-phdr.h>
>>>> #include <dl-prop.h>
>>>> +#include <dl-mmap-prot.h>
>>>> #include <not-cancel.h>
>>>> #include <endian.h>
>>>> @@ -1096,7 +1097,7 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd,
>>>> /* On most platforms presume that PT_GNU_STACK is absent and the stack is
>>>> * executable. Other platforms default to a nonexecutable stack and don't
>>>> * need PT_GNU_STACK to do so. */
>>>> - unsigned int stack_flags = DEFAULT_STACK_PERMS;
>>>> + unsigned int stack_flags = DEFAULT_STACK_PROT_PERMS;
>>>> {
>>>> /* Scan the program header table, collecting its load commands. */
>>>> @@ -1171,18 +1172,7 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd,
>>>> DIAG_POP_NEEDS_COMMENT;
>>>> /* Optimize a common case. */
>>>> -#if (PF_R | PF_W | PF_X) == 7 && (PROT_READ | PROT_WRITE | PROT_EXEC) == 7
>>>> - c->prot = (PF_TO_PROT
>>>> - >> ((ph->p_flags & (PF_R | PF_W | PF_X)) * 4)) & 0xf;
>>>> -#else
>>>> - c->prot = 0;
>>>> - if (ph->p_flags & PF_R)
>>>> - c->prot |= PROT_READ;
>>>> - if (ph->p_flags & PF_W)
>>>> - c->prot |= PROT_WRITE;
>>>> - if (ph->p_flags & PF_X)
>>>> - c->prot |= PROT_EXEC;
>>>> -#endif
>>>> + c->prot = __pf_to_prot (ph->p_flags);
>>>> break;
>>>> case PT_TLS:
>>>> @@ -1219,7 +1209,7 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd,
>>>> break;
>>>> case PT_GNU_STACK:
>>>> - stack_flags = ph->p_flags;
>>>> + stack_flags = __pf_to_prot (ph->p_flags);
>>>> break;
>>>> case PT_GNU_RELRO:
>>>> @@ -1319,7 +1309,7 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd,
>>>> /* Adjust the PT_PHDR value by the runtime load address. */
>>>> l->l_phdr = (ElfW(Phdr) *) ((ElfW(Addr)) l->l_phdr + l->l_addr);
>>>> - if (__glibc_unlikely ((stack_flags &~ GL(dl_stack_flags)) & PF_X))
>>>> + if (__glibc_unlikely ((stack_flags &~ GL(dl_stack_prot_flags)) & PROT_EXEC))
>>>> {
>>>> /* The stack is presently not executable, but this module
>>>> requires that it be executable. Only tries to change the
>>>> diff --git a/elf/dl-mmap-prot.c b/elf/dl-mmap-prot.c
>>>> new file mode 100644
>>>> index 0000000000..6b665d84d4
>>>> --- /dev/null
>>>> +++ b/elf/dl-mmap-prot.c
>>>> @@ -0,0 +1,41 @@
>>>> +/* Convertion from elf p_flags to mmap prot ones.
>>>> + 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 <dl-mmap-prot.h>
>>>> +#include <ldsodefs.h>
>>>> +#include <sys/mman.h>
>>>> +#include <stackinfo.h>
>>>> +
>>>> +int _dl_stack_prot_flags = DEFAULT_STACK_PROT_PERMS;
>>>> +
>>>> +int
>>>> +__pf_to_prot (ElfW(Word) value)
>>>> +{
>>>> +#if (PF_R | PF_W | PF_X) == 7 && (PROT_READ | PROT_WRITE | PROT_EXEC) == 7
>>>> + return (PF_TO_PROT >> ((value & (PF_R | PF_W | PF_X)) * 4)) & 0xf;
>>>> +#else
>>>> + ElfW(Word) ret = 0;
>>>> + if (value & PF_R)
>>>> + ret |= PROT_READ;
>>>> + if (value & PF_W)
>>>> + ret |= PROT_WRITE;
>>>> + if (value & PF_X)
>>>> + ret |= PROT_EXEC;
>>>> + return ret;
>>>> +#endif
>>>> +}
>>>> diff --git a/elf/dl-mmap-prot.h b/elf/dl-mmap-prot.h
>>>> new file mode 100644
>>>> index 0000000000..94286e598f
>>>> --- /dev/null
>>>> +++ b/elf/dl-mmap-prot.h
>>>> @@ -0,0 +1,26 @@
>>>> +/* Convertion from elf p_flags to mmap prot ones.
>>>> + 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 _DL_MMAP_PROT_H
>>>> +#define _DL_MMAP_PROT_H
>>>> +
>>>> +#include <link.h>
>>>> +
>>>> +int __pf_to_prot (ElfW(Word) value);
>>>> +
>>>> +#endif /* _DL_MMAP_PROT_H */
>>>> diff --git a/elf/dl-support.c b/elf/dl-support.c
>>>> index 7b2a1c35d5..2484fa83e4 100644
>>>> --- a/elf/dl-support.c
>>>> +++ b/elf/dl-support.c
>>>> @@ -45,6 +45,7 @@
>>>> #include <array_length.h>
>>>> #include <dl-symbol-redir-ifunc.h>
>>>> #include <dl-tunables.h>
>>>> +#include <dl-mmap-prot.h>
>>>> extern char *__progname;
>>>> char **_dl_argv = &__progname; /* This is checked for some error messages. */
>>>> @@ -166,10 +167,6 @@ enum dso_sort_algorithm _dl_dso_sort_algo;
>>>> /* The value of the FPU control word the kernel will preset in hardware. */
>>>> fpu_control_t _dl_fpu_control = _FPU_DEFAULT;
>>>> -/* Prevailing state of the stack. Generally this includes PF_X, indicating it's
>>>> - * executable but this isn't true for all platforms. */
>>>> -ElfW(Word) _dl_stack_flags = DEFAULT_STACK_PERMS;
>>>> -
>>>> #if PTHREAD_IN_LIBC
>>>> list_t _dl_stack_used;
>>>> list_t _dl_stack_user;
>>>> @@ -322,7 +319,7 @@ _dl_non_dynamic_init (void)
>>>> {
>>>> /* Check if the stack is nonexecutable. */
>>>> case PT_GNU_STACK:
>>>> - _dl_stack_flags = ph->p_flags;
>>>> + _dl_stack_prot_flags = __pf_to_prot (ph->p_flags);
>>>> break;
>>>> case PT_GNU_RELRO:
>>>> diff --git a/elf/rtld.c b/elf/rtld.c
>>>> index 3af8ee63c3..fb76521c27 100644
>>>> --- a/elf/rtld.c
>>>> +++ b/elf/rtld.c
>>>> @@ -52,6 +52,7 @@
>>>> #include <dl-find_object.h>
>>>> #include <dl-audit-check.h>
>>>> #include <dl-call_tls_init_tp.h>
>>>> +#include <dl-mmap-prot.h>
>>>> #include <assert.h>
>>>> @@ -322,7 +323,7 @@ struct rtld_global _rtld_global =
>>>> #include <dl-procruntime.c>
>>>> /* Generally the default presumption without further information is an
>>>> * executable stack but this is not true for all platforms. */
>>>> - ._dl_stack_flags = DEFAULT_STACK_PERMS,
>>>> + ._dl_stack_prot_flags = DEFAULT_STACK_PROT_PERMS,
>>>> #ifdef _LIBC_REENTRANT
>>>> ._dl_load_lock = _RTLD_LOCK_RECURSIVE_INITIALIZER,
>>>> ._dl_load_write_lock = _RTLD_LOCK_RECURSIVE_INITIALIZER,
>>>> @@ -1197,6 +1198,7 @@ rtld_setup_main_map (struct link_map *main_map)
>>>> case PT_GNU_STACK:
>>>> GL(dl_stack_flags) = ph->p_flags;
>>>> + GL(dl_stack_prot_flags) = __pf_to_prot (ph->p_flags);
>>>> break;
>>>> case PT_GNU_RELRO:
>>>> @@ -1502,6 +1504,7 @@ dl_main (const ElfW(Phdr) *phdr,
>>>> if (ph->p_type == PT_GNU_STACK)
>>>> {
>>>> GL(dl_stack_flags) = ph->p_flags;
>>>> + GL(dl_stack_prot_flags) = __pf_to_prot (ph->p_flags);
>>>> break;
>>>> }
>>>> diff --git a/nptl/allocatestack.c b/nptl/allocatestack.c
>>>> index 800ca89720..4c2aacdd10 100644
>>>> --- a/nptl/allocatestack.c
>>>> +++ b/nptl/allocatestack.c
>>>> @@ -150,17 +150,11 @@ get_cached_stack (size_t *sizep, void **memp)
>>>> and fallback to ALLOCATE_GUARD_PROT_NONE if the madvise call fails. */
>>>> static int allocate_stack_mode = ALLOCATE_GUARD_MADV_GUARD;
>>>> -static inline int stack_prot (void)
>>>> -{
>>>> - return (PROT_READ | PROT_WRITE
>>>> - | ((GL(dl_stack_flags) & PF_X) ? PROT_EXEC : 0));
>>>> -}
>>>> -
>>>> static void *
>>>> allocate_thread_stack (size_t size, size_t guardsize)
>>>> {
>>>> /* MADV_ADVISE_GUARD does not require an additional PROT_NONE mapping. */
>>>> - int prot = stack_prot ();
>>>> + int prot = GL(dl_stack_prot_flags);
>>>> if (atomic_load_relaxed (&allocate_stack_mode) == ALLOCATE_GUARD_PROT_NONE)
>>>> /* If a guard page is required, avoid committing memory by first allocate
>>>> @@ -216,7 +210,7 @@ setup_stack_prot (char *mem, size_t size, struct pthread *pd,
>>>> }
>>>> else
>>>> {
>>>> - const int prot = stack_prot ();
>>>> + const int prot = GL(dl_stack_prot_flags);
>>>> char *guardend = guard + guardsize;
>>>> #if _STACK_GROWS_DOWN
>>>> /* As defined at guard_position, for architectures with downward stack
>>>> @@ -294,7 +288,7 @@ adjust_stack_prot (char *mem, size_t size, const struct pthread *pd,
>>>> }
>>>> else if (pd->stack_mode == ALLOCATE_GUARD_PROT_NONE)
>>>> {
>>>> - const int prot = stack_prot ();
>>>> + const int prot = GL(dl_stack_prot_flags);
>>>> #if _STACK_GROWS_DOWN
>>>> return __mprotect (mem + guardsize, slacksize, prot) == 0;
>>>> #else
>>>> diff --git a/support/support_stack_alloc.c b/support/ support_stack_alloc.c
>>>> index 5e576bea74..132e7b4f70 100644
>>>> --- a/support/support_stack_alloc.c
>>>> +++ b/support/support_stack_alloc.c
>>>> @@ -64,11 +64,10 @@ support_stack_alloc (size_t size)
>>>> MAP_PRIVATE|MAP_ANONYMOUS|MAP_NORESERVE| MAP_STACK,
>>>> -1);
>>>> /* Some architecture still requires executable stack for the signal return
>>>> - trampoline, although PF_X could be overridden if PT_GNU_STACK is present.
>>>> - However since glibc does not export such information with a proper ABI,
>>>> - it uses the historical permissions. */
>>>> - int prot = PROT_READ | PROT_WRITE
>>>> - | (DEFAULT_STACK_PERMS & PF_X ? PROT_EXEC : 0);
>>>> + trampoline, although PROT_EXEC could be overridden if PT_GNU_STACK is
>>>> + present. However since glibc does not export such information with a
>>>> + proper ABI, it uses the historical permissions. */
>>>> + int prot = DEFAULT_STACK_PROT_PERMS;
>>>> xmprotect (alloc_base + guardsize, stacksize, prot);
>>>> memset (alloc_base + guardsize, 0xA5, stacksize);
>>>> return (struct support_stack) { alloc_base + guardsize, stacksize, guardsize };
>>>> diff --git a/sysdeps/alpha/stackinfo.h b/sysdeps/alpha/stackinfo.h
>>>> index a469964c10..d69647756b 100644
>>>> --- a/sysdeps/alpha/stackinfo.h
>>>> +++ b/sysdeps/alpha/stackinfo.h
>>>> @@ -26,8 +26,8 @@
>>>> /* On Alpha the stack grows down. */
>>>> #define _STACK_GROWS_DOWN 1
>>>> -/* Default to an executable stack. PF_X can be overridden if PT_GNU_STACK is
>>>> - * present, but it is presumed absent. */
>>>> -#define DEFAULT_STACK_PERMS (PF_R|PF_W|PF_X)
>>>> +/* Default to an executable stack. PROT_EXEC can be overridden if PT_GNU_STACK
>>>> + * is present, but it is presumed absent. */
>>>> +#define DEFAULT_STACK_PROT_PERMS (PROT_READ|PROT_WRITE|PROT_EXEC)
>>>> #endif /* stackinfo.h */
>>>> diff --git a/sysdeps/arm/stackinfo.h b/sysdeps/arm/stackinfo.h
>>>> index 3068352eab..30608f7062 100644
>>>> --- a/sysdeps/arm/stackinfo.h
>>>> +++ b/sysdeps/arm/stackinfo.h
>>>> @@ -26,8 +26,8 @@
>>>> /* On Arm the stack grows down. */
>>>> #define _STACK_GROWS_DOWN 1
>>>> -/* Default to an executable stack. PF_X can be overridden if PT_GNU_STACK is
>>>> - * present, but it is presumed absent. */
>>>> -#define DEFAULT_STACK_PERMS (PF_R|PF_W|PF_X)
>>>> +/* Default to an executable stack. PROT_EXEC can be overridden if PT_GNU_STACK
>>>> + * is present, but it is presumed absent. */
>>>> +#define DEFAULT_STACK_PROT_PERMS (PROT_READ|PROT_WRITE|PROT_EXEC)
>>>> #endif /* stackinfo.h */
>>>> diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
>>>> index fc4a3de767..d92e28d6a9 100644
>>>> --- a/sysdeps/generic/ldsodefs.h
>>>> +++ b/sysdeps/generic/ldsodefs.h
>>>> @@ -419,6 +419,7 @@ struct rtld_global
>>>> /* Prevailing state of the stack, PF_X indicating it's executable. */
>>>> EXTERN ElfW(Word) _dl_stack_flags;
>>>> + EXTERN int _dl_stack_prot_flags;
>>>> /* Flag signalling whether there are gaps in the module ID allocation. */
>>>> EXTERN bool _dl_tls_dtv_gaps;
>>>> diff --git a/sysdeps/generic/stackinfo.h b/sysdeps/generic/stackinfo.h
>>>> index 8abbb3dff7..ab3e72e5c2 100644
>>>> --- a/sysdeps/generic/stackinfo.h
>>>> +++ b/sysdeps/generic/stackinfo.h
>>>> @@ -24,6 +24,6 @@
>>>> #include <elf.h>
>>>> #define _STACK_GROWS_DOWN 1
>>>> -#define DEFAULT_STACK_PERMS (PF_R|PF_W)
>>>> +#define DEFAULT_STACK_PROT_PERMS (PROT_READ|PROT_WRITE)
>>>> #endif
>>>> diff --git a/sysdeps/hppa/stackinfo.h b/sysdeps/hppa/stackinfo.h
>>>> index 53bb11fde0..22920d20a9 100644
>>>> --- a/sysdeps/hppa/stackinfo.h
>>>> +++ b/sysdeps/hppa/stackinfo.h
>>>> @@ -23,9 +23,9 @@
>>>> #include <elf.h>
>>>> -/* Default to an executable stack. PF_X can be overridden if PT_GNU_STACK is
>>>> - * present, but it is presumed absent. */
>>>> -#define DEFAULT_STACK_PERMS (PF_R|PF_W|PF_X)
>>>> +/* Default to an executable stack. PROT_EXEC can be overridden if PT_GNU_STACK
>>>> + * is present, but it is presumed absent. */
>>>> +#define DEFAULT_STACK_PROT_PERMS (PROT_READ|PROT_WRITE|PROT_EXEC)
>>>> /* On PA the stack grows up. */
>>>> #define _STACK_GROWS_UP 1
>>>> diff --git a/sysdeps/i386/stackinfo.h b/sysdeps/i386/stackinfo.h
>>>> index 74e82278d3..8d7a46c405 100644
>>>> --- a/sysdeps/i386/stackinfo.h
>>>> +++ b/sysdeps/i386/stackinfo.h
>>>> @@ -26,9 +26,9 @@
>>>> /* On x86 the stack grows down. */
>>>> #define _STACK_GROWS_DOWN 1
>>>> -/* Default to an executable stack. PF_X can be overridden if PT_GNU_STACK is
>>>> - * present, but it is presumed absent. */
>>>> -#define DEFAULT_STACK_PERMS (PF_R|PF_W|PF_X)
>>>> +/* Default to an executable stack. PROT_EXEC can be overridden if PT_GNU_STACK
>>>> + * is present, but it is presumed absent. */
>>>> +#define DEFAULT_STACK_PROT_PERMS (PROT_READ|PROT_WRITE|PROT_EXEC)
>>>> /* Access to the stack pointer. The macros are used in alloca_account
>>>> for which they need to act as barriers as well, hence the additional
>>>> diff --git a/sysdeps/m68k/stackinfo.h b/sysdeps/m68k/stackinfo.h
>>>> index 7a757df147..77672c71c4 100644
>>>> --- a/sysdeps/m68k/stackinfo.h
>>>> +++ b/sysdeps/m68k/stackinfo.h
>>>> @@ -26,9 +26,9 @@
>>>> /* On m68k the stack grows down. */
>>>> #define _STACK_GROWS_DOWN 1
>>>> -/* Default to an executable stack. PF_X can be overridden if PT_GNU_STACK
>>>> - is present, but it is presumed absent. */
>>>> -#define DEFAULT_STACK_PERMS (PF_R|PF_W|PF_X)
>>>> +/* Default to an executable stack. PROT_EXEC can be overridden if PT_GNU_STACK is
>>>> + * present, but it is presumed absent. */
>>>> +#define DEFAULT_STACK_PROT_PERMS (PROT_READ|PROT_WRITE|PROT_EXEC)
>>>> /* Access to the stack pointer. */
>>>> #define stackinfo_get_sp() \
>>>> diff --git a/sysdeps/mach/htl/pt-stack-alloc.c b/sysdeps/mach/htl/pt- stack-alloc.c
>>>> index 3e196f8ca7..42762bc0ad 100644
>>>> --- a/sysdeps/mach/htl/pt-stack-alloc.c
>>>> +++ b/sysdeps/mach/htl/pt-stack-alloc.c
>>>> @@ -33,7 +33,7 @@ __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)
>>>> + if (GL(dl_stack_prot_flags) & PROT_EXEC)
>>>> prot |= VM_PROT_EXECUTE;
>>>> err = __vm_map (__mach_task_self (), (vm_offset_t *) stackaddr,
>>>> diff --git a/sysdeps/mach/hurd/dl-execstack.c b/sysdeps/mach/hurd/dl- execstack.c
>>>> index dc4719bd38..9e69169367 100644
>>>> --- a/sysdeps/mach/hurd/dl-execstack.c
>>>> +++ b/sysdeps/mach/hurd/dl-execstack.c
>>>> @@ -38,7 +38,7 @@ _dl_make_stack_executable (const void *stack_endp)
>>>> return errno;
>>>> /* Remember that we changed the permission. */
>>>> - GL(dl_stack_flags) |= PF_X;
>>>> + GL(dl_stack_prot_flags) |= PROT_EXEC;
>>>> return 0;
>>>> #else
>>>> diff --git a/sysdeps/microblaze/stackinfo.h b/sysdeps/microblaze/ stackinfo.h
>>>> index 8960bd3d25..51d40a7732 100644
>>>> --- a/sysdeps/microblaze/stackinfo.h
>>>> +++ b/sysdeps/microblaze/stackinfo.h
>>>> @@ -27,8 +27,8 @@
>>>> /* On MicroBlaze the stack grows down. */
>>>> # define _STACK_GROWS_DOWN 1
>>>> -/* Default to an executable stack. PF_X can be overridden if PT_GNU_STACK is
>>>> - * present, but it is presumed absent. */
>>>> -# define DEFAULT_STACK_PERMS (PF_R|PF_W|PF_X)
>>>> +/* Default to an executable stack. PROT_EXEC can be overridden if PT_GNU_STACK
>>>> + * is present, but it is presumed absent. */
>>>> +#define DEFAULT_STACK_PROT_PERMS (PROT_READ|PROT_WRITE|PROT_EXEC)
>>>> #endif /* stackinfo.h. */
>>>> diff --git a/sysdeps/mips/stackinfo.h b/sysdeps/mips/stackinfo.h
>>>> index 6cce9386d6..107a8ea7c9 100644
>>>> --- a/sysdeps/mips/stackinfo.h
>>>> +++ b/sysdeps/mips/stackinfo.h
>>>> @@ -26,8 +26,8 @@
>>>> /* On MIPS the stack grows down. */
>>>> #define _STACK_GROWS_DOWN 1
>>>> -/* Default to an executable stack. PF_X can be overridden if PT_GNU_STACK is
>>>> - * present, but it is presumed absent. */
>>>> -#define DEFAULT_STACK_PERMS (PF_R|PF_W|PF_X)
>>>> +/* Default to an executable stack. PROT_EXEC can be overridden if PT_GNU_STACK
>>>> + * is present, but it is presumed absent. */
>>>> +#define DEFAULT_STACK_PROT_PERMS (PROT_READ|PROT_WRITE|PROT_EXEC)
>>>> #endif /* stackinfo.h */
>>>> diff --git a/sysdeps/or1k/stackinfo.h b/sysdeps/or1k/stackinfo.h
>>>> index 39cf5c2456..d93a795c51 100644
>>>> --- a/sysdeps/or1k/stackinfo.h
>>>> +++ b/sysdeps/or1k/stackinfo.h
>>>> @@ -27,8 +27,8 @@
>>>> /* On or1k the stack grows down. */
>>>> #define _STACK_GROWS_DOWN 1
>>>> -/* Default to an executable stack. PF_X can be overridden if PT_GNU_STACK is
>>>> - present, but it is presumed absent. */
>>>> -#define DEFAULT_STACK_PERMS (PF_R | PF_W | PF_X)
>>>> +/* Default to an executable stack. PROT_EXEC can be overridden if PT_GNU_STACK
>>>> + * is present, but it is presumed absent. */
>>>> +#define DEFAULT_STACK_PROT_PERMS (PROT_READ|PROT_WRITE|PROT_EXEC)
>>>> #endif /* stackinfo.h */
>>>> diff --git a/sysdeps/powerpc/powerpc32/stackinfo.h b/sysdeps/powerpc/ powerpc32/stackinfo.h
>>>> index 31cba55805..50a3b367c6 100644
>>>> --- a/sysdeps/powerpc/powerpc32/stackinfo.h
>>>> +++ b/sysdeps/powerpc/powerpc32/stackinfo.h
>>>> @@ -26,7 +26,7 @@
>>>> /* On PPC the stack grows down. */
>>>> #define _STACK_GROWS_DOWN 1
>>>> -/* PF_X can be overridden if PT_GNU_STACK is present but is presumed absent. */
>>>> -#define DEFAULT_STACK_PERMS (PF_R|PF_W|PF_X)
>>>> +/* PROT_EXEC can be overridden if PT_GNU_STACK is present but is presumed absent. */
>>>> +#define DEFAULT_STACK_PROT_PERMS (PROT_READ|PROT_WRITE|PROT_EXEC)
>>>> #endif /* stackinfo.h */
>>>> diff --git a/sysdeps/s390/stackinfo.h b/sysdeps/s390/stackinfo.h
>>>> index 657ab3487f..9be764495a 100644
>>>> --- a/sysdeps/s390/stackinfo.h
>>>> +++ b/sysdeps/s390/stackinfo.h
>>>> @@ -26,8 +26,8 @@
>>>> /* On s390 the stack grows down. */
>>>> #define _STACK_GROWS_DOWN 1
>>>> -/* Default to an executable stack. PF_X can be overridden if PT_GNU_STACK is
>>>> - * present, but it is presumed absent. */
>>>> -#define DEFAULT_STACK_PERMS (PF_R|PF_W|PF_X)
>>>> +/* Default to an executable stack. PROT_EXEC can be overridden if PT_GNU_STACK
>>>> + * is present, but it is presumed absent. */
>>>> +#define DEFAULT_STACK_PROT_PERMS (PROT_READ|PROT_WRITE|PROT_EXEC)
>>>> #endif /* stackinfo.h */
>>>> diff --git a/sysdeps/sh/stackinfo.h b/sysdeps/sh/stackinfo.h
>>>> index 8f7bf163be..e502993d24 100644
>>>> --- a/sysdeps/sh/stackinfo.h
>>>> +++ b/sysdeps/sh/stackinfo.h
>>>> @@ -26,8 +26,8 @@
>>>> /* On SH the stack grows down. */
>>>> #define _STACK_GROWS_DOWN 1
>>>> -/* Default to an executable stack. PF_X can be overridden if PT_GNU_STACK is
>>>> - * present, but it is presumed absent. */
>>>> -#define DEFAULT_STACK_PERMS (PF_R|PF_W|PF_X)
>>>> +/* Default to an executable stack. PROT_EXEC can be overridden if PT_GNU_STACK
>>>> + * is present, but it is presumed absent. */
>>>> +#define DEFAULT_STACK_PROT_PERMS (PROT_READ|PROT_WRITE|PROT_EXEC)
>>>> #endif /* stackinfo.h */
>>>> diff --git a/sysdeps/sparc/stackinfo.h b/sysdeps/sparc/stackinfo.h
>>>> index 23a74ed7fe..a4a0eb15c9 100644
>>>> --- a/sysdeps/sparc/stackinfo.h
>>>> +++ b/sysdeps/sparc/stackinfo.h
>>>> @@ -26,8 +26,8 @@
>>>> /* On sparc the stack grows down. */
>>>> #define _STACK_GROWS_DOWN 1
>>>> -/* Default to an executable stack. PF_X can be overridden if PT_GNU_STACK is
>>>> - * present, but it is presumed absent. */
>>>> -#define DEFAULT_STACK_PERMS (PF_R|PF_W|PF_X)
>>>> +/* Default to an executable stack. PROT_EXEC can be overridden if PT_GNU_STACK
>>>> + * is present, but it is presumed absent. */
>>>> +#define DEFAULT_STACK_PROT_PERMS (PROT_READ|PROT_WRITE|PROT_EXEC)
>>>> #endif /* stackinfo.h */
>>>> diff --git a/sysdeps/unix/sysv/linux/dl-execstack.c b/sysdeps/unix/ sysv/linux/dl-execstack.c
>>>> index 6db9601656..81edcc8567 100644
>>>> --- a/sysdeps/unix/sysv/linux/dl-execstack.c
>>>> +++ b/sysdeps/unix/sysv/linux/dl-execstack.c
>>>> @@ -36,7 +36,7 @@ _dl_make_stack_executable (const void *stack_endp)
>>>> return errno;
>>>> /* Remember that we changed the permission. */
>>>> - GL(dl_stack_flags) |= PF_X;
>>>> + GL(dl_stack_prot_flags) |= PROT_EXEC;
>>>> return 0;
>>>> }
>>>> diff --git a/sysdeps/unix/sysv/linux/spawni.c b/sysdeps/unix/sysv/ linux/spawni.c
>>>> index eca1a84254..bc8476ff11 100644
>>>> --- a/sysdeps/unix/sysv/linux/spawni.c
>>>> +++ b/sysdeps/unix/sysv/linux/spawni.c
>>>> @@ -348,9 +348,6 @@ __spawnix (int *pid, const char *file,
>>>> return errno;
>>>> }
>>>> - int prot = (PROT_READ | PROT_WRITE
>>>> - | ((GL (dl_stack_flags) & PF_X) ? PROT_EXEC : 0));
>>>> -
>>>> /* Add a slack area for child's stack. */
>>>> size_t argv_size = (argc * sizeof (void *)) + 512;
>>>> /* We need at least a few pages in case the compiler's stack checking is
>>>> @@ -361,7 +358,7 @@ __spawnix (int *pid, const char *file,
>>>> where it might use about 1k extra stack space). */
>>>> argv_size += (32 * 1024);
>>>> size_t stack_size = ALIGN_UP (argv_size, GLRO(dl_pagesize));
>>>> - void *stack = __mmap (NULL, stack_size, prot,
>>>> + void *stack = __mmap (NULL, stack_size, GL (dl_stack_prot_flags),
>>>> MAP_PRIVATE | MAP_ANONYMOUS | MAP_STACK, -1, 0);
>>>> if (__glibc_unlikely (stack == MAP_FAILED))
>>>> return errno;
>>>> diff --git a/sysdeps/x86_64/stackinfo.h b/sysdeps/x86_64/stackinfo.h
>>>> index 416d687869..0e88e6d94e 100644
>>>> --- a/sysdeps/x86_64/stackinfo.h
>>>> +++ b/sysdeps/x86_64/stackinfo.h
>>>> @@ -32,9 +32,9 @@
>>>> /* On x86_64 the stack grows down. */
>>>> #define _STACK_GROWS_DOWN 1
>>>> -/* Default to an executable stack. PF_X can be overridden if PT_GNU_STACK is
>>>> - * present, but it is presumed absent. */
>>>> -#define DEFAULT_STACK_PERMS (PF_R|PF_W|PF_X)
>>>> +/* Default to an executable stack. PROT_EXEC can be overridden if PT_GNU_STACK
>>>> + * is present, but it is presumed absent. */
>>>> +#define DEFAULT_STACK_PROT_PERMS (PROT_READ|PROT_WRITE|PROT_EXEC)
>>>> /* Access to the stack pointer. The macros are used in alloca_account
>>>> for which they need to act as barriers as well, hence the additional
>>>
>>
>
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