[PATCH v2] elf: early conversion of elf p_flags to mprotect flags
Cupertino Miranda
cupertino.miranda@oracle.com
Thu Jul 3 11:36:17 GMT 2025
Hi everyone,
New version after Adhmervals review.
Adhmerval: Thank you for the suggested solution.
Looking for your feedback.
Best regards,
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 | 2 +-
elf/dl-execstack-tunable.c | 2 +-
elf/dl-load.c | 19 +++-----------
elf/dl-support.c | 7 +++---
elf/rtld.c | 12 ++++-----
include/alloca.h | 2 --
include/stackinfo.h | 34 ++++++++++++++++++++++++++
nptl/allocatestack.c | 12 +++------
support/support_stack_alloc.c | 9 +++----
sysdeps/alpha/stackinfo.h | 6 ++---
sysdeps/arm/stackinfo.h | 6 ++---
sysdeps/generic/ldsodefs.h | 2 +-
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 | 3 ++-
sysdeps/unix/sysv/linux/machine-sp.h | 2 ++
sysdeps/unix/sysv/linux/spawni.c | 5 +---
sysdeps/x86_64/stackinfo.h | 6 ++---
29 files changed, 102 insertions(+), 91 deletions(-)
diff --git a/elf/Makefile b/elf/Makefile
index 362523ff11..95da4229b6 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -2156,7 +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 6e26ef0583..1d7ec9c047 100644
--- a/elf/dl-load.c
+++ b/elf/dl-load.c
@@ -1096,7 +1096,7 @@ _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 +1171,7 @@ _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 +1208,7 @@ _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 +1308,7 @@ _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-support.c b/elf/dl-support.c
index 7b2a1c35d5..bbef3ab6b6 100644
--- a/elf/dl-support.c
+++ b/elf/dl-support.c
@@ -166,9 +166,8 @@ 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;
+/* Required flags used for stack allocation. */
+int _dl_stack_prot_flags = DEFAULT_STACK_PROT_PERMS;
#if PTHREAD_IN_LIBC
list_t _dl_stack_used;
@@ -322,7 +321,7 @@ _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 e6a181dc31..74364bc8ed 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -322,7 +322,7 @@ 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,
@@ -1198,7 +1198,7 @@ rtld_setup_main_map (struct link_map *main_map)
break;
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:
@@ -1488,12 +1488,12 @@ dl_main (const ElfW(Phdr) *phdr,
--_dl_argc;
++_dl_argv;
- /* The initialization of _dl_stack_flags done below assumes the
+ /* The initialization of dl_stack_prot_flags done below assumes the
executable's PT_GNU_STACK may have been honored by the kernel, and
so a PT_GNU_STACK with PF_X set means the stack started out with
execute permission. However, this is not really true if the
dynamic linker is the executable the kernel loaded. For this
- case, we must reinitialize _dl_stack_flags to match the dynamic
+ case, we must reinitialize dl_stack_prot_flags to match the dynamic
linker itself. If the dynamic linker was built with a
PT_GNU_STACK, then the kernel may have loaded us with a
nonexecutable stack that we will have to make executable when we
@@ -1503,7 +1503,7 @@ dl_main (const ElfW(Phdr) *phdr,
for (const ElfW(Phdr) *ph = phdr; ph < &phdr[phnum]; ++ph)
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;
}
@@ -1624,8 +1624,6 @@ dl_main (const ElfW(Phdr) *phdr,
bool has_interp = rtld_setup_main_map (main_map);
- /* Handle this after PT_GNU_STACK parse, because it updates dl_stack_flags
- if required. */
_dl_handle_execstack_tunable ();
/* If the current libname is different from the SONAME, add the
diff --git a/include/alloca.h b/include/alloca.h
index c0b8395443..1bd3af3e27 100644
--- a/include/alloca.h
+++ b/include/alloca.h
@@ -4,8 +4,6 @@
# ifndef _ISOMAC
-#include <stackinfo.h>
-
#undef __alloca
/* Now define the internal interfaces. */
diff --git a/include/stackinfo.h b/include/stackinfo.h
index 3c1541b42d..b2d9ed174f 100644
--- a/include/stackinfo.h
+++ b/include/stackinfo.h
@@ -39,4 +39,38 @@
# error "stackinfo.h must define _STACK_GROWS_UP or _STACK_GROWS_DOWN!"
#endif
+#include <sys/mman.h>
+#include <link.h>
+
+/* ELF uses the PF_x macros to specify the segment permissions, mmap
+ uses PROT_xxx. In most cases the three macros have the values 1, 2,
+ and 3 but not in a matching order. The following macros allows
+ converting from the PF_x values to PROT_xxx values. */
+#define PF_TO_PROT \
+ ((PROT_READ << (PF_R * 4)) \
+ | (PROT_WRITE << (PF_W * 4)) \
+ | (PROT_EXEC << (PF_X * 4)) \
+ | ((PROT_READ | PROT_WRITE) << ((PF_R | PF_W) * 4)) \
+ | ((PROT_READ | PROT_EXEC) << ((PF_R | PF_X) * 4)) \
+ | ((PROT_WRITE | PROT_EXEC) << (PF_W | PF_X) * 4) \
+ | ((PROT_READ | PROT_WRITE | PROT_EXEC) << ((PF_R | PF_W | PF_X) * 4)))
+
+static inline 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
+
+}
+
#endif /* include/stackinfo.h */
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..bcf9582df4 100644
--- a/sysdeps/generic/ldsodefs.h
+++ b/sysdeps/generic/ldsodefs.h
@@ -418,7 +418,7 @@ struct rtld_global
#include <dl-procruntime.c>
/* 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..a59bd5632a 100644
--- a/sysdeps/unix/sysv/linux/dl-execstack.c
+++ b/sysdeps/unix/sysv/linux/dl-execstack.c
@@ -17,6 +17,7 @@
<https://www.gnu.org/licenses/>. */
#include <ldsodefs.h>
+#include <stackinfo.h>
int
_dl_make_stack_executable (const void *stack_endp)
@@ -36,7 +37,7 @@ _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/machine-sp.h b/sysdeps/unix/sysv/linux/machine-sp.h
index 6ab3ca6d50..bda90fe801 100644
--- a/sysdeps/unix/sysv/linux/machine-sp.h
+++ b/sysdeps/unix/sysv/linux/machine-sp.h
@@ -19,6 +19,8 @@
#ifndef _MACHINE_SP_H
#define _MACHINE_SP_H
+#include <stackinfo.h>
+
/* Return the current stack pointer. */
static inline uintptr_t
__thread_stack_pointer (void)
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
--
2.39.5
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