-/* Copyright (C) 2002-2007, 2009, 2010 Free Software Foundation, Inc.
+/* Copyright (C) 2002-2019 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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, write to the Free
- Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
- 02111-1307 USA. */
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
#include <assert.h>
#include <errno.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <dl-sysdep.h>
+#include <dl-tls.h>
#include <tls.h>
+#include <list.h>
#include <lowlevellock.h>
+#include <futex-internal.h>
#include <kernel-features.h>
+#include <stack-aliasing.h>
#ifndef NEED_SEPARATE_REGISTER_STACK
list_t __stack_user __attribute__ ((nocommon));
hidden_data_def (__stack_user)
-#if COLORING_INCREMENT != 0
-/* Number of threads created. */
-static unsigned int nptl_ncreated;
-#endif
-
/* Check whether the stack is still used or not. */
#define FREE_P(descr) ((descr)->tid <= 0)
return NULL;
}
+ /* Don't allow setxid until cloned. */
+ result->setxid_futex = -1;
+
/* Dequeue the entry. */
stack_list_del (&result->list);
/* Clear the DTV. */
dtv_t *dtv = GET_DTV (TLS_TPADJ (result));
+ for (size_t cnt = 0; cnt < dtv[-1].counter; ++cnt)
+ free (dtv[1 + cnt].pointer.to_free);
memset (dtv, '\0', (dtv[-1].counter + 1) * sizeof (dtv_t));
/* Re-initialize the TLS. */
/* Free stacks until cache size is lower than LIMIT. */
-void
-__free_stacks (size_t limit)
+static void
+free_stacks (size_t limit)
{
/* We reduce the size of the cache. Remove the last entries until
the size is below the limit. */
/* Remove this block. This should never fail. If it does
something is really wrong. */
- if (munmap (curr->stackblock, curr->stackblock_size) != 0)
+ if (__munmap (curr->stackblock, curr->stackblock_size) != 0)
abort ();
/* Maybe we have freed enough. */
}
}
+/* Free all the stacks on cleanup. */
+void
+__nptl_stacks_freeres (void)
+{
+ free_stacks (0);
+}
/* Add a stack frame which is not used anymore to the stack. Must be
called with the cache lock held. */
stack_list_add (&stack->list, &stack_cache);
stack_cache_actsize += stack->stackblock_size;
- if (__builtin_expect (stack_cache_actsize > stack_cache_maxsize, 0))
- __free_stacks (stack_cache_maxsize);
+ if (__glibc_unlikely (stack_cache_actsize > stack_cache_maxsize))
+ free_stacks (stack_cache_maxsize);
}
static int
-internal_function
change_stack_perm (struct pthread *pd
#ifdef NEED_SEPARATE_REGISTER_STACK
, size_t pagemask
#else
# error "Define either _STACK_GROWS_DOWN or _STACK_GROWS_UP"
#endif
- if (mprotect (stack, len, PROT_READ | PROT_WRITE | PROT_EXEC) != 0)
+ if (__mprotect (stack, len, PROT_READ | PROT_WRITE | PROT_EXEC) != 0)
return errno;
return 0;
}
+/* Return the guard page position on allocated stack. */
+static inline char *
+__attribute ((always_inline))
+guard_position (void *mem, size_t size, size_t guardsize, struct pthread *pd,
+ size_t pagesize_m1)
+{
+#ifdef NEED_SEPARATE_REGISTER_STACK
+ return mem + (((size - guardsize) / 2) & ~pagesize_m1);
+#elif _STACK_GROWS_DOWN
+ return mem;
+#elif _STACK_GROWS_UP
+ return (char *) (((uintptr_t) pd - guardsize) & ~pagesize_m1);
+#endif
+}
+/* Based on stack allocated with PROT_NONE, setup the required portions with
+ 'prot' flags based on the guard page position. */
+static inline int
+setup_stack_prot (char *mem, size_t size, char *guard, size_t guardsize,
+ const int prot)
+{
+ char *guardend = guard + guardsize;
+#if _STACK_GROWS_DOWN && !defined(NEED_SEPARATE_REGISTER_STACK)
+ /* As defined at guard_position, for architectures with downward stack
+ the guard page is always at start of the allocated area. */
+ if (__mprotect (guardend, size - guardsize, prot) != 0)
+ return errno;
+#else
+ size_t mprots1 = (uintptr_t) guard - (uintptr_t) mem;
+ if (__mprotect (mem, mprots1, prot) != 0)
+ return errno;
+ size_t mprots2 = ((uintptr_t) mem + size) - (uintptr_t) guardend;
+ if (__mprotect (guardend, mprots2, prot) != 0)
+ return errno;
+#endif
+ return 0;
+}
+
+/* Mark the memory of the stack as usable to the kernel. It frees everything
+ except for the space used for the TCB itself. */
+static inline void
+__always_inline
+advise_stack_range (void *mem, size_t size, uintptr_t pd, size_t guardsize)
+{
+ uintptr_t sp = (uintptr_t) CURRENT_STACK_FRAME;
+ size_t pagesize_m1 = __getpagesize () - 1;
+#if _STACK_GROWS_DOWN && !defined(NEED_SEPARATE_REGISTER_STACK)
+ size_t freesize = (sp - (uintptr_t) mem) & ~pagesize_m1;
+ assert (freesize < size);
+ if (freesize > PTHREAD_STACK_MIN)
+ __madvise (mem, freesize - PTHREAD_STACK_MIN, MADV_DONTNEED);
+#else
+ /* Page aligned start of memory to free (higher than or equal
+ to current sp plus the minimum stack size). */
+ uintptr_t freeblock = (sp + PTHREAD_STACK_MIN + pagesize_m1) & ~pagesize_m1;
+ uintptr_t free_end = (pd - guardsize) & ~pagesize_m1;
+ if (free_end > freeblock)
+ {
+ size_t freesize = free_end - freeblock;
+ assert (freesize < size);
+ __madvise ((void*) freeblock, freesize, MADV_DONTNEED);
+ }
+#endif
+}
+
+/* Returns a usable stack for a new thread either by allocating a
+ new stack or reusing a cached stack of sufficient size.
+ ATTR must be non-NULL and point to a valid pthread_attr.
+ PDP must be non-NULL. */
static int
allocate_stack (const struct pthread_attr *attr, struct pthread **pdp,
ALLOCATE_STACK_PARMS)
struct pthread *pd;
size_t size;
size_t pagesize_m1 = __getpagesize () - 1;
- void *stacktop;
- assert (attr != NULL);
assert (powerof2 (pagesize_m1 + 1));
assert (TCB_ALIGNMENT >= STACK_ALIGN);
/* Get the stack size from the attribute if it is set. Otherwise we
use the default we determined at start time. */
- size = attr->stacksize ?: __default_stacksize;
+ if (attr->stacksize != 0)
+ size = attr->stacksize;
+ else
+ {
+ lll_lock (__default_pthread_attr_lock, LLL_PRIVATE);
+ size = __default_pthread_attr.stacksize;
+ lll_unlock (__default_pthread_attr_lock, LLL_PRIVATE);
+ }
/* Get memory for the stack. */
- if (__builtin_expect (attr->flags & ATTR_FLAG_STACKADDR, 0))
+ if (__glibc_unlikely (attr->flags & ATTR_FLAG_STACKADDR))
{
uintptr_t adj;
+ char *stackaddr = (char *) attr->stackaddr;
+
+ /* Assume the same layout as the _STACK_GROWS_DOWN case, with struct
+ pthread at the top of the stack block. Later we adjust the guard
+ location and stack address to match the _STACK_GROWS_UP case. */
+ if (_STACK_GROWS_UP)
+ stackaddr += attr->stacksize;
/* If the user also specified the size of the stack make sure it
is large enough. */
/* Adjust stack size for alignment of the TLS block. */
#if TLS_TCB_AT_TP
- adj = ((uintptr_t) attr->stackaddr - TLS_TCB_SIZE)
+ adj = ((uintptr_t) stackaddr - TLS_TCB_SIZE)
& __static_tls_align_m1;
assert (size > adj + TLS_TCB_SIZE);
#elif TLS_DTV_AT_TP
- adj = ((uintptr_t) attr->stackaddr - __static_tls_size)
+ adj = ((uintptr_t) stackaddr - __static_tls_size)
& __static_tls_align_m1;
assert (size > adj);
#endif
the stack. It is the user's responsibility to do this if it
is wanted. */
#if TLS_TCB_AT_TP
- pd = (struct pthread *) ((uintptr_t) attr->stackaddr
+ pd = (struct pthread *) ((uintptr_t) stackaddr
- TLS_TCB_SIZE - adj);
#elif TLS_DTV_AT_TP
- pd = (struct pthread *) (((uintptr_t) attr->stackaddr
+ pd = (struct pthread *) (((uintptr_t) stackaddr
- __static_tls_size - adj)
- TLS_PRE_TCB_SIZE);
#endif
pd->specific[0] = pd->specific_1stblock;
/* Remember the stack-related values. */
- pd->stackblock = (char *) attr->stackaddr - size;
+ pd->stackblock = (char *) stackaddr - size;
pd->stackblock_size = size;
/* This is a user-provided stack. It will not be queued in the
__pthread_multiple_threads = *__libc_multiple_threads_ptr = 1;
#endif
-#ifndef __ASSUME_PRIVATE_FUTEX
- /* The thread must know when private futexes are supported. */
- pd->header.private_futex = THREAD_GETMEM (THREAD_SELF,
- header.private_futex);
-#endif
-
#ifdef NEED_DL_SYSINFO
- /* Copy the sysinfo value from the parent. */
- THREAD_SYSINFO(pd) = THREAD_SELF_SYSINFO;
+ SETUP_THREAD_SYSINFO (pd);
#endif
- /* The process ID is also the same as that of the caller. */
- pd->pid = THREAD_GETMEM (THREAD_SELF, pid);
+ /* Don't allow setxid until cloned. */
+ pd->setxid_futex = -1;
/* Allocate the DTV for this thread. */
if (_dl_allocate_tls (TLS_TPADJ (pd)) == NULL)
{
/* Something went wrong. */
assert (errno == ENOMEM);
- return EAGAIN;
+ return errno;
}
const int prot = (PROT_READ | PROT_WRITE
| ((GL(dl_stack_flags) & PF_X) ? PROT_EXEC : 0));
-#if COLORING_INCREMENT != 0
- /* Add one more page for stack coloring. Don't do it for stacks
- with 16 times pagesize or larger. This might just cause
- unnecessary misalignment. */
- if (size <= 16 * pagesize_m1)
- size += pagesize_m1 + 1;
-#endif
-
/* Adjust the stack size for alignment. */
size &= ~__static_tls_align_m1;
assert (size != 0);
/* Make sure the size of the stack is enough for the guard and
eventually the thread descriptor. */
guardsize = (attr->guardsize + pagesize_m1) & ~pagesize_m1;
+ if (guardsize < attr->guardsize || size + guardsize < guardsize)
+ /* Arithmetic overflow. */
+ return EINVAL;
+ size += guardsize;
if (__builtin_expect (size < ((guardsize + __static_tls_size
+ MINIMAL_REST_STACK + pagesize_m1)
& ~pagesize_m1),
size += pagesize_m1 + 1;
#endif
- mem = mmap (NULL, size, prot,
- MAP_PRIVATE | MAP_ANONYMOUS | MAP_STACK, -1, 0);
+ /* If a guard page is required, avoid committing memory by first
+ allocate with PROT_NONE and then reserve with required permission
+ excluding the guard page. */
+ mem = __mmap (NULL, size, (guardsize == 0) ? prot : PROT_NONE,
+ MAP_PRIVATE | MAP_ANONYMOUS | MAP_STACK, -1, 0);
- if (__builtin_expect (mem == MAP_FAILED, 0))
- {
- if (errno == ENOMEM)
- __set_errno (EAGAIN);
-
- return errno;
- }
+ if (__glibc_unlikely (mem == MAP_FAILED))
+ return errno;
/* SIZE is guaranteed to be greater than zero.
So we can never get a null pointer back from mmap. */
assert (mem != NULL);
-#if COLORING_INCREMENT != 0
- /* Atomically increment NCREATED. */
- unsigned int ncreated = atomic_increment_val (&nptl_ncreated);
-
- /* We chose the offset for coloring by incrementing it for
- every new thread by a fixed amount. The offset used
- module the page size. Even if coloring would be better
- relative to higher alignment values it makes no sense to
- do it since the mmap() interface does not allow us to
- specify any alignment for the returned memory block. */
- size_t coloring = (ncreated * COLORING_INCREMENT) & pagesize_m1;
-
- /* Make sure the coloring offsets does not disturb the alignment
- of the TCB and static TLS block. */
- if (__builtin_expect ((coloring & __static_tls_align_m1) != 0, 0))
- coloring = (((coloring + __static_tls_align_m1)
- & ~(__static_tls_align_m1))
- & ~pagesize_m1);
-#else
- /* Unless specified we do not make any adjustments. */
-# define coloring 0
-#endif
-
/* Place the thread descriptor at the end of the stack. */
#if TLS_TCB_AT_TP
- pd = (struct pthread *) ((char *) mem + size - coloring) - 1;
+ pd = (struct pthread *) ((char *) mem + size) - 1;
#elif TLS_DTV_AT_TP
- pd = (struct pthread *) ((((uintptr_t) mem + size - coloring
+ pd = (struct pthread *) ((((uintptr_t) mem + size
- __static_tls_size)
& ~__static_tls_align_m1)
- TLS_PRE_TCB_SIZE);
#endif
+ /* Now mprotect the required region excluding the guard area. */
+ if (__glibc_likely (guardsize > 0))
+ {
+ char *guard = guard_position (mem, size, guardsize, pd,
+ pagesize_m1);
+ if (setup_stack_prot (mem, size, guard, guardsize, prot) != 0)
+ {
+ __munmap (mem, size);
+ return errno;
+ }
+ }
+
/* Remember the stack-related values. */
pd->stackblock = mem;
pd->stackblock_size = size;
+ /* Update guardsize for newly allocated guardsize to avoid
+ an mprotect in guard resize below. */
+ pd->guardsize = guardsize;
/* We allocated the first block thread-specific data array.
This address will not change for the lifetime of this
__pthread_multiple_threads = *__libc_multiple_threads_ptr = 1;
#endif
-#ifndef __ASSUME_PRIVATE_FUTEX
- /* The thread must know when private futexes are supported. */
- pd->header.private_futex = THREAD_GETMEM (THREAD_SELF,
- header.private_futex);
-#endif
-
#ifdef NEED_DL_SYSINFO
- /* Copy the sysinfo value from the parent. */
- THREAD_SYSINFO(pd) = THREAD_SELF_SYSINFO;
+ SETUP_THREAD_SYSINFO (pd);
#endif
- /* The process ID is also the same as that of the caller. */
- pd->pid = THREAD_GETMEM (THREAD_SELF, pid);
+ /* Don't allow setxid until cloned. */
+ pd->setxid_futex = -1;
/* Allocate the DTV for this thread. */
if (_dl_allocate_tls (TLS_TPADJ (pd)) == NULL)
assert (errno == ENOMEM);
/* Free the stack memory we just allocated. */
- (void) munmap (mem, size);
+ (void) __munmap (mem, size);
- return EAGAIN;
+ return errno;
}
if (err != 0)
{
/* Free the stack memory we just allocated. */
- (void) munmap (mem, size);
+ (void) __munmap (mem, size);
return err;
}
}
/* Create or resize the guard area if necessary. */
- if (__builtin_expect (guardsize > pd->guardsize, 0))
+ if (__glibc_unlikely (guardsize > pd->guardsize))
{
-#ifdef NEED_SEPARATE_REGISTER_STACK
- char *guard = mem + (((size - guardsize) / 2) & ~pagesize_m1);
-#elif _STACK_GROWS_DOWN
- char *guard = mem;
-# elif _STACK_GROWS_UP
- char *guard = (char *) (((uintptr_t) pd - guardsize) & ~pagesize_m1);
-#endif
- if (mprotect (guard, guardsize, PROT_NONE) != 0)
+ char *guard = guard_position (mem, size, guardsize, pd,
+ pagesize_m1);
+ if (__mprotect (guard, guardsize, PROT_NONE) != 0)
{
- int err;
mprot_error:
- err = errno;
-
lll_lock (stack_cache_lock, LLL_PRIVATE);
/* Remove the thread from the list. */
of memory caused problems we better do not use it
anymore. Uh, and we ignore possible errors. There
is nothing we could do. */
- (void) munmap (mem, size);
+ (void) __munmap (mem, size);
- return err;
+ return errno;
}
pd->guardsize = guardsize;
char *oldguard = mem + (((size - pd->guardsize) / 2) & ~pagesize_m1);
if (oldguard < guard
- && mprotect (oldguard, guard - oldguard, prot) != 0)
+ && __mprotect (oldguard, guard - oldguard, prot) != 0)
goto mprot_error;
- if (mprotect (guard + guardsize,
+ if (__mprotect (guard + guardsize,
oldguard + pd->guardsize - guard - guardsize,
prot) != 0)
goto mprot_error;
#elif _STACK_GROWS_DOWN
- if (mprotect ((char *) mem + guardsize, pd->guardsize - guardsize,
+ if (__mprotect ((char *) mem + guardsize, pd->guardsize - guardsize,
prot) != 0)
goto mprot_error;
#elif _STACK_GROWS_UP
- if (mprotect ((char *) pd - pd->guardsize,
- pd->guardsize - guardsize, prot) != 0)
+ char *new_guard = (char *)(((uintptr_t) pd - guardsize)
+ & ~pagesize_m1);
+ char *old_guard = (char *)(((uintptr_t) pd - pd->guardsize)
+ & ~pagesize_m1);
+ /* The guard size difference might be > 0, but once rounded
+ to the nearest page the size difference might be zero. */
+ if (new_guard > old_guard
+ && __mprotect (old_guard, new_guard - old_guard, prot) != 0)
goto mprot_error;
#endif
- offsetof (pthread_mutex_t,
__data.__list.__next));
pd->robust_head.list_op_pending = NULL;
-#ifdef __PTHREAD_MUTEX_HAVE_PREV
+#if __PTHREAD_MUTEX_HAVE_PREV
pd->robust_prev = &pd->robust_head;
#endif
pd->robust_head.list = &pd->robust_head;
/* We place the thread descriptor at the end of the stack. */
*pdp = pd;
-#if TLS_TCB_AT_TP
+#if _STACK_GROWS_DOWN
+ void *stacktop;
+
+# if TLS_TCB_AT_TP
/* The stack begins before the TCB and the static TLS block. */
stacktop = ((char *) (pd + 1) - __static_tls_size);
-#elif TLS_DTV_AT_TP
+# elif TLS_DTV_AT_TP
stacktop = (char *) (pd - 1);
-#endif
+# endif
-#ifdef NEED_SEPARATE_REGISTER_STACK
+# ifdef NEED_SEPARATE_REGISTER_STACK
*stack = pd->stackblock;
*stacksize = stacktop - *stack;
-#elif _STACK_GROWS_DOWN
+# else
*stack = stacktop;
-#elif _STACK_GROWS_UP
+# endif
+#else
*stack = pd->stackblock;
- assert (*stack > 0);
#endif
return 0;
void
-internal_function
__deallocate_stack (struct pthread *pd)
{
lll_lock (stack_cache_lock, LLL_PRIVATE);
not reset the 'used' flag in the 'tid' field. This is done by
the kernel. If no thread has been created yet this field is
still zero. */
- if (__builtin_expect (! pd->user_stack, 1))
+ if (__glibc_likely (! pd->user_stack))
(void) queue_stack (pd);
else
/* Free the memory associated with the ELF TLS. */
int
-internal_function
__make_stacks_executable (void **stack_endp)
{
/* First the main thread's stack. */
if (in_flight_stack != 0)
{
bool add_p = in_flight_stack & 1;
- list_t *elem = (list_t *) (in_flight_stack & ~UINTMAX_C (1));
+ list_t *elem = (list_t *) (in_flight_stack & ~(uintptr_t) 1);
if (add_p)
{
- /* We always add at the beginning of the list. So in this
- case we only need to check the beginning of these lists. */
- int check_list (list_t *l)
- {
- if (l->next->prev != l)
- {
- assert (l->next->prev == elem);
-
- elem->next = l->next;
- elem->prev = l;
- l->next = elem;
-
- return 1;
- }
-
- return 0;
- }
-
- if (check_list (&stack_used) == 0)
- (void) check_list (&stack_cache);
+ /* We always add at the beginning of the list. So in this case we
+ only need to check the beginning of these lists to see if the
+ pointers at the head of the list are inconsistent. */
+ list_t *l = NULL;
+
+ if (stack_used.next->prev != &stack_used)
+ l = &stack_used;
+ else if (stack_cache.next->prev != &stack_cache)
+ l = &stack_cache;
+
+ if (l != NULL)
+ {
+ assert (l->next->prev == elem);
+ elem->next = l->next;
+ elem->prev = l;
+ l->next = elem;
+ }
}
else
{
/* This marks the stack as free. */
curp->tid = 0;
- /* The PID field must be initialized for the new process. */
- curp->pid = self->pid;
-
/* Account for the size of the stack. */
stack_cache_actsize += curp->stackblock_size;
}
}
- /* Reset the PIDs in any cached stacks. */
- list_for_each (runp, &stack_cache)
- {
- struct pthread *curp = list_entry (runp, struct pthread, list);
- curp->pid = self->pid;
- }
-
/* Add the stack of all running threads to the cache. */
list_splice (&stack_used, &stack_cache);
INIT_LIST_HEAD (&stack_used);
INIT_LIST_HEAD (&__stack_user);
- if (__builtin_expect (THREAD_GETMEM (self, user_stack), 0))
+ if (__glibc_unlikely (THREAD_GETMEM (self, user_stack)))
list_add (&self->list, &__stack_user);
else
list_add (&self->list, &stack_used);
in_flight_stack = 0;
- /* Initialize the lock. */
+ /* Initialize locks. */
stack_cache_lock = LLL_LOCK_INITIALIZER;
+ __default_pthread_attr_lock = LLL_LOCK_INITIALIZER;
}
#endif
+#ifdef SIGSETXID
static void
-internal_function
setxid_mark_thread (struct xid_command *cmdp, struct pthread *t)
{
int ch;
if (t->setxid_futex == -1
&& ! atomic_compare_and_exchange_bool_acq (&t->setxid_futex, -2, -1))
do
- lll_futex_wait (&t->setxid_futex, -2, LLL_PRIVATE);
+ futex_wait_simple (&t->setxid_futex, -2, FUTEX_PRIVATE);
while (t->setxid_futex == -2);
/* Don't let the thread exit before the setxid handler runs. */
/* If the thread is exiting right now, ignore it. */
if ((ch & EXITING_BITMASK) != 0)
- return;
+ {
+ /* Release the futex if there is no other setxid in
+ progress. */
+ if ((ch & SETXID_BITMASK) == 0)
+ {
+ t->setxid_futex = 1;
+ futex_wake (&t->setxid_futex, 1, FUTEX_PRIVATE);
+ }
+ return;
+ }
}
while (atomic_compare_and_exchange_bool_acq (&t->cancelhandling,
ch | SETXID_BITMASK, ch));
static void
-internal_function
setxid_unmark_thread (struct xid_command *cmdp, struct pthread *t)
{
int ch;
/* Release the futex just in case. */
t->setxid_futex = 1;
- lll_futex_wake (&t->setxid_futex, 1, LLL_PRIVATE);
+ futex_wake (&t->setxid_futex, 1, FUTEX_PRIVATE);
}
static int
-internal_function
setxid_signal_thread (struct xid_command *cmdp, struct pthread *t)
{
if ((t->cancelhandling & SETXID_BITMASK) == 0)
return 0;
int val;
+ pid_t pid = __getpid ();
INTERNAL_SYSCALL_DECL (err);
-#if __ASSUME_TGKILL
- val = INTERNAL_SYSCALL (tgkill, err, 3, THREAD_GETMEM (THREAD_SELF, pid),
- t->tid, SIGSETXID);
-#else
-# ifdef __NR_tgkill
- val = INTERNAL_SYSCALL (tgkill, err, 3, THREAD_GETMEM (THREAD_SELF, pid),
- t->tid, SIGSETXID);
- if (INTERNAL_SYSCALL_ERROR_P (val, err)
- && INTERNAL_SYSCALL_ERRNO (val, err) == ENOSYS)
-# endif
- val = INTERNAL_SYSCALL (tkill, err, 2, t->tid, SIGSETXID);
-#endif
+ val = INTERNAL_SYSCALL_CALL (tgkill, err, pid, t->tid, SIGSETXID);
/* If this failed, it must have had not started yet or else exited. */
if (!INTERNAL_SYSCALL_ERROR_P (val, err))
return 0;
}
+/* Check for consistency across set*id system call results. The abort
+ should not happen as long as all privileges changes happen through
+ the glibc wrappers. ERROR must be 0 (no error) or an errno
+ code. */
+void
+attribute_hidden
+__nptl_setxid_error (struct xid_command *cmdp, int error)
+{
+ do
+ {
+ int olderror = cmdp->error;
+ if (olderror == error)
+ break;
+ if (olderror != -1)
+ {
+ /* Mismatch between current and previous results. Save the
+ error value to memory so that is not clobbered by the
+ abort function and preserved in coredumps. */
+ volatile int xid_err __attribute__((unused)) = error;
+ abort ();
+ }
+ }
+ while (atomic_compare_and_exchange_bool_acq (&cmdp->error, error, -1));
+}
int
attribute_hidden
__xidcmd = cmdp;
cmdp->cntr = 0;
+ cmdp->error = -1;
struct pthread *self = THREAD_SELF;
int cur = cmdp->cntr;
while (cur != 0)
{
- lll_futex_wait (&cmdp->cntr, cur, LLL_PRIVATE);
+ futex_wait_simple ((unsigned int *) &cmdp->cntr, cur,
+ FUTEX_PRIVATE);
cur = cmdp->cntr;
}
}
INTERNAL_SYSCALL_DECL (err);
result = INTERNAL_SYSCALL_NCS (cmdp->syscall_no, err, 3,
cmdp->id[0], cmdp->id[1], cmdp->id[2]);
- if (INTERNAL_SYSCALL_ERROR_P (result, err))
+ int error = 0;
+ if (__glibc_unlikely (INTERNAL_SYSCALL_ERROR_P (result, err)))
{
- __set_errno (INTERNAL_SYSCALL_ERRNO (result, err));
+ error = INTERNAL_SYSCALL_ERRNO (result, err);
+ __set_errno (error);
result = -1;
}
+ __nptl_setxid_error (cmdp, error);
lll_unlock (stack_cache_lock, LLL_PRIVATE);
return result;
}
+#endif /* SIGSETXID. */
+
static inline void __attribute__((always_inline))
init_one_static_tls (struct pthread *curp, struct link_map *map)
{
- dtv_t *dtv = GET_DTV (TLS_TPADJ (curp));
# if TLS_TCB_AT_TP
void *dest = (char *) curp - map->l_tls_offset;
# elif TLS_DTV_AT_TP
# error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
# endif
- /* Fill in the DTV slot so that a later LD/GD access will find it. */
- dtv[map->l_tls_modid].pointer.val = dest;
- dtv[map->l_tls_modid].pointer.is_static = true;
-
/* Initialize the memory. */
memset (__mempcpy (dest, map->l_tls_initimage, map->l_tls_initimage_size),
'\0', map->l_tls_blocksize - map->l_tls_initimage_size);
continue;
do
- lll_futex_wait (gscope_flagp, THREAD_GSCOPE_FLAG_WAIT, LLL_PRIVATE);
+ futex_wait_simple ((unsigned int *) gscope_flagp,
+ THREAD_GSCOPE_FLAG_WAIT, FUTEX_PRIVATE);
while (*gscope_flagp == THREAD_GSCOPE_FLAG_WAIT);
}
continue;
do
- lll_futex_wait (gscope_flagp, THREAD_GSCOPE_FLAG_WAIT, LLL_PRIVATE);
+ futex_wait_simple ((unsigned int *) gscope_flagp,
+ THREAD_GSCOPE_FLAG_WAIT, FUTEX_PRIVATE);
while (*gscope_flagp == THREAD_GSCOPE_FLAG_WAIT);
}
projects / thirdparty / glibc.git / blobdiff