aboutsummaryrefslogtreecommitdiff
path: root/elf
diff options
context:
space:
mode:
Diffstat (limited to 'elf')
-rw-r--r--elf/dl-misc.c142
-rw-r--r--elf/dl-tls.c34
2 files changed, 16 insertions, 160 deletions
diff --git a/elf/dl-misc.c b/elf/dl-misc.c
index 043185a..8fd6710 100644
--- a/elf/dl-misc.c
+++ b/elf/dl-misc.c
@@ -19,7 +19,6 @@
#include <assert.h>
#include <fcntl.h>
#include <ldsodefs.h>
-#include <libc-symbols.h>
#include <limits.h>
#include <link.h>
#include <stdarg.h>
@@ -365,144 +364,3 @@ _dl_higher_prime_number (unsigned long int n)
return *low;
}
-
-/* To support accessing TLS variables from signal handlers, we need an
- async signal safe memory allocator. These routines are never
- themselves invoked reentrantly (all calls to them are surrounded by
- signal masks) but may be invoked concurrently from many threads.
- The current implementation is not particularly performant nor space
- efficient, but it will be used rarely (and only in binaries that use
- dlopen.) The API matches that of malloc() and friends. */
-
-struct __signal_safe_allocator_header
-{
- size_t size;
- void *start;
-};
-
-static inline struct __signal_safe_allocator_header *
-ptr_to_signal_safe_allocator_header (void *ptr)
-{
- return (struct __signal_safe_allocator_header *)
- ((char *) (ptr) - sizeof (struct __signal_safe_allocator_header));
-}
-
-void *weak_function
-__signal_safe_memalign (size_t boundary, size_t size)
-{
- struct __signal_safe_allocator_header *header;
-
- if (boundary < sizeof (*header))
- boundary = sizeof (*header);
-
- /* Boundary must be a power of two. */
- if (!powerof2 (boundary))
- return NULL;
-
- size_t pg = GLRO (dl_pagesize);
- size_t padded_size;
- if (boundary <= pg)
- {
- /* We'll get a pointer certainly aligned to boundary, so just
- add one more boundary-sized chunk to hold the header. */
- padded_size = roundup (size, boundary) + boundary;
- }
- else
- {
- /* If we want K pages aligned to a J-page boundary, K+J+1 pages
- contains at least one such region that isn't directly at the start
- (so we can place the header.) This is wasteful, but you're the one
- who wanted 64K-aligned TLS. */
- padded_size = roundup (size, pg) + boundary + pg;
- }
-
-
- size_t actual_size = roundup (padded_size, pg);
- void *actual = mmap (NULL, actual_size, PROT_READ | PROT_WRITE,
- MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
- if (actual == MAP_FAILED)
- return NULL;
-
- if (boundary <= pg)
- {
- header = actual + boundary - sizeof (*header);
- }
- else
- {
- intptr_t actual_pg = ((intptr_t) actual) / pg;
- intptr_t boundary_pg = boundary / pg;
- intptr_t start_pg = actual_pg + boundary_pg;
- start_pg -= start_pg % boundary_pg;
- if (start_pg > (actual_pg + 1))
- {
- int ret = munmap (actual, (start_pg - actual_pg - 1) * pg);
- assert (ret == 0);
- actual = (void *) ((start_pg - 1) * pg);
- }
- char *start = (void *) (start_pg * pg);
- header = ptr_to_signal_safe_allocator_header (start);
- }
-
- header->size = actual_size;
- header->start = actual;
- void *ptr = header;
- ptr += sizeof (*header);
- if (((intptr_t) ptr) % boundary != 0)
- _dl_fatal_printf ("__signal_safe_memalign produced incorrect alignment\n");
- return ptr;
-}
-
-void * weak_function
-__signal_safe_malloc (size_t size)
-{
- return __signal_safe_memalign (1, size);
-}
-
-void weak_function
-__signal_safe_free (void *ptr)
-{
- if (ptr == NULL)
- return;
-
- struct __signal_safe_allocator_header *header
- = ptr_to_signal_safe_allocator_header (ptr);
- int ret = munmap (header->start, header->size);
-
- assert (ret == 0);
-}
-
-void * weak_function
-__signal_safe_realloc (void *ptr, size_t size)
-{
- if (size == 0)
- {
- __signal_safe_free (ptr);
- return NULL;
- }
- if (ptr == NULL)
- return __signal_safe_malloc (size);
-
- struct __signal_safe_allocator_header *header
- = ptr_to_signal_safe_allocator_header (ptr);
- size_t old_size = header->size;
- if (old_size - sizeof (*header) >= size)
- return ptr;
-
- void *new_ptr = __signal_safe_malloc (size);
- if (new_ptr == NULL)
- return NULL;
-
- memcpy (new_ptr, ptr, old_size);
- __signal_safe_free (ptr);
-
- return new_ptr;
-}
-
-void * weak_function
-__signal_safe_calloc (size_t nmemb, size_t size)
-{
- void *ptr = __signal_safe_malloc (nmemb * size);
- if (ptr == NULL)
- return NULL;
- return memset (ptr, 0, nmemb * size);
-}
diff --git a/elf/dl-tls.c b/elf/dl-tls.c
index c1802e7..28e4fbe 100644
--- a/elf/dl-tls.c
+++ b/elf/dl-tls.c
@@ -293,7 +293,7 @@ allocate_dtv (void *result)
initial set of modules. This should avoid in most cases expansions
of the dtv. */
dtv_length = GL(dl_tls_max_dtv_idx) + DTV_SURPLUS;
- dtv = __signal_safe_calloc (dtv_length + 2, sizeof (dtv_t));
+ dtv = calloc (dtv_length + 2, sizeof (dtv_t));
if (dtv != NULL)
{
/* This is the initial length of the dtv. */
@@ -470,7 +470,7 @@ _dl_clear_dtv (dtv_t *dtv)
for (size_t cnt = 0; cnt < dtv[-1].counter; ++cnt)
if (! dtv[1 + cnt].pointer.is_static
&& dtv[1 + cnt].pointer.val != TLS_DTV_UNALLOCATED)
- __signal_safe_free (dtv[1 + cnt].pointer.val);
+ free (dtv[1 + cnt].pointer.val);
memset (dtv, '\0', (dtv[-1].counter + 1) * sizeof (dtv_t));
}
@@ -491,11 +491,11 @@ _dl_deallocate_tls (void *tcb, bool dealloc_tcb)
for (size_t cnt = 0; cnt < dtv[-1].counter; ++cnt)
if (! dtv[1 + cnt].pointer.is_static
&& dtv[1 + cnt].pointer.val != TLS_DTV_UNALLOCATED)
- __signal_safe_free (dtv[1 + cnt].pointer.val);
+ free (dtv[1 + cnt].pointer.val);
/* The array starts with dtv[-1]. */
if (dtv != GL(dl_initial_dtv))
- __signal_safe_free (dtv - 1);
+ free (dtv - 1);
if (dealloc_tcb)
{
@@ -537,7 +537,8 @@ static void *
allocate_and_init (struct link_map *map)
{
void *newp;
- newp = __signal_safe_memalign (map->l_tls_align, map->l_tls_blocksize);
+
+ newp = __libc_memalign (map->l_tls_align, map->l_tls_blocksize);
if (newp == NULL)
oom ();
@@ -607,27 +608,25 @@ _dl_update_slotinfo (unsigned long int req_modid)
if (gen <= dtv[0].counter)
continue;
- size_t modid = total + cnt;
-
/* If there is no map this means the entry is empty. */
struct link_map *map = listp->slotinfo[cnt].map;
if (map == NULL)
{
/* If this modid was used at some point the memory
might still be allocated. */
- if (dtv[-1].counter >= modid
- && !dtv[modid].pointer.is_static
- && dtv[modid].pointer.val != TLS_DTV_UNALLOCATED)
+ if (! dtv[total + cnt].pointer.is_static
+ && dtv[total + cnt].pointer.val != TLS_DTV_UNALLOCATED)
{
- __signal_safe_free (dtv[modid].pointer.val);
- dtv[modid].pointer.val = TLS_DTV_UNALLOCATED;
+ free (dtv[total + cnt].pointer.val);
+ dtv[total + cnt].pointer.val = TLS_DTV_UNALLOCATED;
}
continue;
}
- assert (modid == map->l_tls_modid);
/* Check whether the current dtv array is large enough. */
+ size_t modid = map->l_tls_modid;
+ assert (total + cnt == modid);
if (dtv[-1].counter < modid)
{
/* Reallocate the dtv. */
@@ -641,18 +640,17 @@ _dl_update_slotinfo (unsigned long int req_modid)
{
/* This is the initial dtv that was allocated
during rtld startup using the dl-minimal.c
- malloc instead of the real allocator. We can't
+ malloc instead of the real malloc. We can't
free it, we have to abandon the old storage. */
- newp = __signal_safe_malloc (
- (2 + newsize) * sizeof (dtv_t));
+ newp = malloc ((2 + newsize) * sizeof (dtv_t));
if (newp == NULL)
oom ();
memcpy (newp, &dtv[-1], (2 + oldsize) * sizeof (dtv_t));
}
else
{
- newp = __signal_safe_realloc (&dtv[-1],
+ newp = realloc (&dtv[-1],
(2 + newsize) * sizeof (dtv_t));
if (newp == NULL)
oom ();
@@ -682,7 +680,7 @@ _dl_update_slotinfo (unsigned long int req_modid)
deallocate even if it is this dtv entry we are
supposed to load. The reason is that we call
memalign and not malloc. */
- __signal_safe_free (dtv[modid].pointer.val);
+ free (dtv[modid].pointer.val);
/* This module is loaded dynamically- We defer memory
allocation. */
generated by cgit v1.1 at 2024-12-22 08:56:54 +0000