/* Relocate a shared object and resolve its references to other loaded objects.
- Copyright (C) 1995-2004, 2005, 2006 Free Software Foundation, Inc.
+ Copyright (C) 1995-2019 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
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 <errno.h>
#include <libintl.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <sys/types.h>
+#include <_itoa.h>
+#include <libc-pointer-arith.h>
#include "dynamic-link.h"
/* Statistics function. */
This function intentionally does not return any value but signals error
directly, as static TLS should be rare and code handling it should
not be inlined as much as possible. */
-void
-internal_function __attribute_noinline__
-_dl_allocate_static_tls (struct link_map *map)
+int
+_dl_try_allocate_static_tls (struct link_map *map)
{
- /* If the alignment requirements are too high fail. */
- if (map->l_tls_align > GL(dl_tls_static_align))
+ /* If we've already used the variable with dynamic access, or if the
+ alignment requirements are too high, fail. */
+ if (map->l_tls_offset == FORCED_DYNAMIC_TLS_OFFSET
+ || map->l_tls_align > GL(dl_tls_static_align))
{
fail:
- _dl_signal_error (0, map->l_name, NULL, N_("\
-cannot allocate memory in static TLS block"));
+ return -1;
}
#if TLS_TCB_AT_TP
- size_t freebytes;
- size_t n;
- size_t blsize;
-
- freebytes = GL(dl_tls_static_size) - GL(dl_tls_static_used) - TLS_TCB_SIZE;
+ size_t freebytes = GL(dl_tls_static_size) - GL(dl_tls_static_used);
+ if (freebytes < TLS_TCB_SIZE)
+ goto fail;
+ freebytes -= TLS_TCB_SIZE;
- blsize = map->l_tls_blocksize + map->l_tls_firstbyte_offset;
+ size_t blsize = map->l_tls_blocksize + map->l_tls_firstbyte_offset;
if (freebytes < blsize)
goto fail;
- n = (freebytes - blsize) / map->l_tls_align;
+ size_t n = (freebytes - blsize) / map->l_tls_align;
size_t offset = GL(dl_tls_static_used) + (freebytes - n * map->l_tls_align
- map->l_tls_firstbyte_offset);
map->l_tls_offset = GL(dl_tls_static_used) = offset;
#elif TLS_DTV_AT_TP
- size_t used;
- size_t check;
-
- size_t offset = roundup (GL(dl_tls_static_used), map->l_tls_align);
- used = offset + map->l_tls_blocksize;
- check = used;
/* dl_tls_static_used includes the TCB at the beginning. */
+ size_t offset = (ALIGN_UP(GL(dl_tls_static_used)
+ - map->l_tls_firstbyte_offset,
+ map->l_tls_align)
+ + map->l_tls_firstbyte_offset);
+ size_t used = offset + map->l_tls_blocksize;
- if (check > GL(dl_tls_static_size))
+ if (used > GL(dl_tls_static_size))
goto fail;
map->l_tls_offset = offset;
+ map->l_tls_firstbyte_offset = GL(dl_tls_static_used);
GL(dl_tls_static_used) = used;
#else
# error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
}
else
map->l_need_tls_init = 1;
+
+ return 0;
+}
+
+void
+__attribute_noinline__
+_dl_allocate_static_tls (struct link_map *map)
+{
+ if (map->l_tls_offset == FORCED_DYNAMIC_TLS_OFFSET
+ || _dl_try_allocate_static_tls (map))
+ {
+ _dl_signal_error (0, map->l_name, NULL, N_("\
+cannot allocate memory in static TLS block"));
+ }
}
/* Initialize static TLS area and DTV for current (only) thread.
# 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_t *dtv = THREAD_DTV ();
- assert (map->l_tls_modid <= dtv[-1].counter);
- 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);
void
_dl_relocate_object (struct link_map *l, struct r_scope_elem *scope[],
- int lazy, int consider_profiling)
+ int reloc_mode, int consider_profiling)
{
struct textrels
{
} *textrels = NULL;
/* Initialize it to make the compiler happy. */
const char *errstring = NULL;
+ int lazy = reloc_mode & RTLD_LAZY;
+ int skip_ifunc = reloc_mode & __RTLD_NOIFUNC;
#ifdef SHARED
/* If we are auditing, install the same handlers we need for profiling. */
- consider_profiling |= GLRO(dl_audit) != NULL;
+ if ((reloc_mode & __RTLD_AUDIT) == 0)
+ consider_profiling |= GLRO(dl_audit) != NULL;
#elif defined PROF
/* Never use dynamic linker profiling for gprof profiling code. */
# define consider_profiling 0
&& __builtin_expect (l->l_info[DT_BIND_NOW] != NULL, 0))
lazy = 0;
- if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_RELOC, 0))
+ if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_RELOC))
_dl_debug_printf ("\nrelocation processing: %s%s\n",
- l->l_name[0] ? l->l_name : rtld_progname,
- lazy ? " (lazy)" : "");
+ DSO_FILENAME (l->l_name), lazy ? " (lazy)" : "");
/* DT_TEXTREL is now in level 2 and might phase out at some time.
But we rewrite the DT_FLAGS entry to a DT_TEXTREL entry to make
testing easier and therefore it will be available at all time. */
- if (__builtin_expect (l->l_info[DT_TEXTREL] != NULL, 0))
+ if (__glibc_unlikely (l->l_info[DT_TEXTREL] != NULL))
{
/* Bletch. We must make read-only segments writable
long enough to relocate them. */
struct textrels *newp;
newp = (struct textrels *) alloca (sizeof (*newp));
- newp->len = (((ph->p_vaddr + ph->p_memsz + GLRO(dl_pagesize) - 1)
- & ~(GLRO(dl_pagesize) - 1))
- - (ph->p_vaddr & ~(GLRO(dl_pagesize) - 1)));
- newp->start = ((ph->p_vaddr & ~(GLRO(dl_pagesize) - 1))
- + (caddr_t) l->l_addr);
-
- if (__mprotect (newp->start, newp->len, PROT_READ|PROT_WRITE) < 0)
- {
- errstring = N_("cannot make segment writable for relocation");
- call_error:
- _dl_signal_error (errno, l->l_name, NULL, errstring);
- }
+ newp->len = ALIGN_UP (ph->p_vaddr + ph->p_memsz, GLRO(dl_pagesize))
+ - ALIGN_DOWN (ph->p_vaddr, GLRO(dl_pagesize));
+ newp->start = PTR_ALIGN_DOWN (ph->p_vaddr, GLRO(dl_pagesize))
+ + (caddr_t) l->l_addr;
-#if (PF_R | PF_W | PF_X) == 7 && (PROT_READ | PROT_WRITE | PROT_EXEC) == 7
- newp->prot = (PF_TO_PROT
- >> ((ph->p_flags & (PF_R | PF_W | PF_X)) * 4)) & 0xf;
-#else
newp->prot = 0;
if (ph->p_flags & PF_R)
newp->prot |= PROT_READ;
newp->prot |= PROT_WRITE;
if (ph->p_flags & PF_X)
newp->prot |= PROT_EXEC;
-#endif
+
+ if (__mprotect (newp->start, newp->len, newp->prot|PROT_WRITE) < 0)
+ {
+ errstring = N_("cannot make segment writable for relocation");
+ call_error:
+ _dl_signal_error (errno, l->l_name, NULL, errstring);
+ }
+
newp->next = textrels;
textrels = newp;
}
/* This macro is used as a callback from the ELF_DYNAMIC_RELOCATE code. */
#define RESOLVE_MAP(ref, version, r_type) \
- (ELFW(ST_BIND) ((*ref)->st_info) != STB_LOCAL \
+ ((ELFW(ST_BIND) ((*ref)->st_info) != STB_LOCAL \
+ && __glibc_likely (!dl_symbol_visibility_binds_local_p (*ref))) \
? ((__builtin_expect ((*ref) == l->l_lookup_cache.sym, 0) \
&& elf_machine_type_class (r_type) == l->l_lookup_cache.type_class) \
? (bump_num_cache_relocations (), \
l->l_lookup_cache.type_class = _tc; \
l->l_lookup_cache.sym = (*ref); \
const struct r_found_version *v = NULL; \
- int flags = DL_LOOKUP_ADD_DEPENDENCY; \
if ((version) != NULL && (version)->hash != 0) \
- { \
- v = (version); \
- flags = 0; \
- } \
+ v = (version); \
_lr = _dl_lookup_symbol_x (strtab + (*ref)->st_name, l, (ref), \
- scope, v, _tc, flags, NULL); \
+ scope, v, _tc, \
+ DL_LOOKUP_ADD_DEPENDENCY, NULL); \
l->l_lookup_cache.ret = (*ref); \
l->l_lookup_cache.value = _lr; })) \
: l)
- /* This macro is used as a callback from elf_machine_rel{a,} when a
- static TLS reloc is about to be performed. Since (in dl-load.c) we
- permit dynamic loading of objects that might use such relocs, we
- have to check whether each use is actually doable. If the object
- whose TLS segment the reference resolves to was allocated space in
- the static TLS block at startup, then it's ok. Otherwise, we make
- an attempt to allocate it in surplus space on the fly. If that
- can't be done, we fall back to the error that DF_STATIC_TLS is
- intended to produce. */
-#define CHECK_STATIC_TLS(map, sym_map) \
- do { \
- if (__builtin_expect ((sym_map)->l_tls_offset == NO_TLS_OFFSET, 0)) \
- _dl_allocate_static_tls (sym_map); \
- } while (0)
-
#include "dynamic-link.h"
- ELF_DYNAMIC_RELOCATE (l, lazy, consider_profiling);
+ ELF_DYNAMIC_RELOCATE (l, lazy, consider_profiling, skip_ifunc);
#ifndef PROF
- if (__builtin_expect (consider_profiling, 0))
+ if (__glibc_unlikely (consider_profiling)
+ && l->l_info[DT_PLTRELSZ] != NULL)
{
/* Allocate the array which will contain the already found
relocations. If the shared object lacks a PLT (for example
if it only contains lead function) the l_info[DT_PLTRELSZ]
will be NULL. */
- if (l->l_info[DT_PLTRELSZ] == NULL)
- {
- errstring = N_("%s: no PLTREL found in object %s\n");
- fatal:
- _dl_fatal_printf (errstring,
- rtld_progname ?: "<program name unknown>",
- l->l_name);
- }
+ size_t sizeofrel = l->l_info[DT_PLTREL]->d_un.d_val == DT_RELA
+ ? sizeof (ElfW(Rela))
+ : sizeof (ElfW(Rel));
+ size_t relcount = l->l_info[DT_PLTRELSZ]->d_un.d_val / sizeofrel;
+ l->l_reloc_result = calloc (sizeof (l->l_reloc_result[0]), relcount);
- l->l_reloc_result = calloc (sizeof (l->l_reloc_result[0]),
- l->l_info[DT_PLTRELSZ]->d_un.d_val);
if (l->l_reloc_result == NULL)
{
errstring = N_("\
%s: out of memory to store relocation results for %s\n");
- goto fatal;
+ _dl_fatal_printf (errstring, RTLD_PROGNAME, l->l_name);
}
}
#endif
goto call_error;
}
+#ifdef CLEAR_CACHE
+ CLEAR_CACHE (textrels->start, textrels->start + textrels->len);
+#endif
+
textrels = textrels->next;
}
}
-void internal_function
+void
_dl_protect_relro (struct link_map *l)
{
- ElfW(Addr) start = ((l->l_addr + l->l_relro_addr)
- & ~(GLRO(dl_pagesize) - 1));
- ElfW(Addr) end = ((l->l_addr + l->l_relro_addr + l->l_relro_size)
- & ~(GLRO(dl_pagesize) - 1));
-
+ ElfW(Addr) start = ALIGN_DOWN((l->l_addr
+ + l->l_relro_addr),
+ GLRO(dl_pagesize));
+ ElfW(Addr) end = ALIGN_DOWN((l->l_addr
+ + l->l_relro_addr
+ + l->l_relro_size),
+ GLRO(dl_pagesize));
if (start != end
&& __mprotect ((void *) start, end - start, PROT_READ) < 0)
{
}
void
-internal_function __attribute_noinline__
+__attribute_noinline__
_dl_reloc_bad_type (struct link_map *map, unsigned int type, int plt)
{
- extern const char INTUSE(_itoa_lower_digits)[] attribute_hidden;
-#define DIGIT(b) INTUSE(_itoa_lower_digits)[(b) & 0xf];
+#define DIGIT(b) _itoa_lower_digits[(b) & 0xf];
/* XXX We cannot translate these messages. */
static const char msg[2][32