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-rw-r--r--elf/Makefile2
-rw-r--r--elf/dl-caller.c85
-rw-r--r--elf/dl-load.c5
-rw-r--r--elf/dl-open.c68
-rw-r--r--elf/rtld.c12
5 files changed, 104 insertions, 68 deletions
diff --git a/elf/Makefile b/elf/Makefile
index 68474825c7..a366a687de 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -30,7 +30,7 @@ routines = $(dl-routines) dl-open dl-close dl-support dl-iteratephdr \
dl-routines = $(addprefix dl-,load cache lookup object reloc deps \
runtime error init fini debug misc \
version profile conflict tls origin \
- execstack)
+ execstack caller)
all-dl-routines = $(dl-routines) $(sysdep-dl-routines)
# But they are absent from the shared libc, because that code is in ld.so.
elide-routines.os = $(all-dl-routines) dl-support enbl-secure dl-origin
diff --git a/elf/dl-caller.c b/elf/dl-caller.c
new file mode 100644
index 0000000000..ddabbd0f2d
--- /dev/null
+++ b/elf/dl-caller.c
@@ -0,0 +1,85 @@
+/* Check whether caller comes from the right place.
+ Copyright (C) 2004 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, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <assert.h>
+#include <ldsodefs.h>
+#include <stddef.h>
+#include <caller.h>
+#include <gnu/lib-names.h>
+
+
+int
+attribute_hidden
+_dl_check_caller (const void *caller, enum allowmask mask)
+{
+ static const char expected1[] = LIBC_SO;
+ static const char expected2[] = LIBDL_SO;
+#ifdef LIBPTHREAD_SO
+ static const char expected3[] = LIBPTHREAD_SO;
+#endif
+ static const char expected4[] = LD_SO;
+
+ for (struct link_map *l = GL(dl_loaded); l != NULL; l = l->l_next)
+ if (caller >= (const void *) l->l_map_start
+ && caller < (const void *) l->l_text_end)
+ {
+ /* The address falls into this DSO's address range. Check the
+ name. */
+ if ((mask & allow_libc) && strcmp (expected1, l->l_name) == 0)
+ return 0;
+ if ((mask & allow_libdl) && strcmp (expected2, l->l_name) == 0)
+ return 0;
+#ifdef LIBPTHREAD_SO
+ if ((mask & allow_libpthread) && strcmp (expected3, l->l_name) == 0)
+ return 0;
+#endif
+ if ((mask & allow_ldso) && strcmp (expected4, l->l_name) == 0)
+ return 0;
+
+ struct libname_list *runp = l->l_libname;
+
+ while (runp != NULL)
+ {
+ if ((mask & allow_libc) && strcmp (expected1, runp->name) == 0)
+ return 0;
+ if ((mask & allow_libdl) && strcmp (expected2, runp->name) == 0)
+ return 0;
+#ifdef LIBPTHREAD_SO
+ if ((mask & allow_libpthread)
+ && strcmp (expected3, runp->name) == 0)
+ return 0;
+#endif
+ if ((mask & allow_ldso) && strcmp (expected4, runp->name) == 0)
+ return 0;
+
+ runp = runp->next;
+ }
+
+ break;
+ }
+
+ /* Maybe the dynamic linker is not yet on the list. */
+ if ((mask & allow_ldso) != 0
+ && caller >= (const void *) GL(dl_rtld_map).l_map_start
+ && caller < (const void *) GL(dl_rtld_map).l_text_end)
+ return 0;
+
+ /* No valid caller. */
+ return 1;
+}
diff --git a/elf/dl-load.c b/elf/dl-load.c
index 1a3c9c5ed9..162fb30af3 100644
--- a/elf/dl-load.c
+++ b/elf/dl-load.c
@@ -1110,7 +1110,7 @@ cannot allocate TLS data structures for initial thread");
unallocated. Then jump into the normal segment-mapping loop to
handle the portion of the segment past the end of the file
mapping. */
- __mprotect ((caddr_t) (l->l_addr + c->mapend),
+ __mprotect ((caddr_t) l->l_text_end,
loadcmds[nloadcmds - 1].allocend - c->mapend,
PROT_NONE);
@@ -1146,6 +1146,9 @@ cannot allocate TLS data structures for initial thread");
goto map_error;
postmap:
+ if (c->prot & PROT_EXEC)
+ l->l_text_end = l->l_addr + c->mapend;
+
if (l->l_phdr == 0
&& (ElfW(Off)) c->mapoff <= header->e_phoff
&& ((size_t) (c->mapend - c->mapstart + c->mapoff)
diff --git a/elf/dl-open.c b/elf/dl-open.c
index 47db84c867..70f2fb20bc 100644
--- a/elf/dl-open.c
+++ b/elf/dl-open.c
@@ -30,7 +30,7 @@
#include <bits/libc-lock.h>
#include <ldsodefs.h>
#include <bp-sym.h>
-#include <gnu/lib-names.h>
+#include <caller.h>
#include <dl-dst.h>
@@ -156,68 +156,6 @@ add_to_global (struct link_map *new)
}
-#ifdef SHARED
-static int
-internal_function
-check_libc_caller (const void *caller)
-{
- static const char expected1[] = LIBC_SO;
- static const char expected2[] = LIBDL_SO;
-
- /* If we already know the address ranges, just test. */
- static const void *expected1_from;
- static const void *expected1_to;
- static const void *expected2_from;
- static const void *expected2_to;
-
- if (expected1_from == NULL)
- {
- /* The only other DSO which is allowed to call these functions is
- libdl. Find the address range containing the caller. */
- struct link_map *l;
-
- for (l = GL(dl_loaded); l != NULL; l = l->l_next)
- if (strcmp (expected1, l->l_name) == 0)
- {
- is_1:
- expected1_from = (const void *) l->l_map_start;
- expected1_to = (const void *) l->l_map_end;
- }
- else if (strcmp (expected2, l->l_name) == 0)
- {
- is_2:
- expected2_from = (const void *) l->l_map_start;
- expected2_to = (const void *) l->l_map_end;
- }
- else
- {
- struct libname_list *runp = l->l_libname;
-
- while (runp != NULL)
- {
- if (strcmp (expected1, runp->name) == 0)
- goto is_1;
- else if (strcmp (expected2, runp->name) == 0)
- goto is_2;
-
- runp = runp->next;
- }
- }
-
- assert (expected1_from != NULL);
- }
-
- /* When there would be more than two expected caller we could use an
- array for the values but for now this is cheaper. */
- if ((caller >= expected1_from && caller < expected1_to)
- || (caller >= expected2_from && caller < expected2_to))
- return 0;
-
- return 1;
-}
-#endif
-
-
static void
dl_open_worker (void *a)
{
@@ -232,11 +170,9 @@ dl_open_worker (void *a)
bool any_tls;
#endif
-#ifdef SHARED
/* Check whether _dl_open() has been called from a valid DSO. */
- if (check_libc_caller (args->caller_dl_open) != 0)
+ if (__check_caller (args->caller_dl_open, allow_libc|allow_libdl) != 0)
GLRO(dl_signal_error) (0, "dlopen", NULL, N_("invalid caller"));
-#endif
/* Maybe we have to expand a DST. */
dst = strchr (file, '$');
diff --git a/elf/rtld.c b/elf/rtld.c
index 139358c80d..31521c6484 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -142,6 +142,7 @@ struct rtld_global_ro _rtld_global_ro attribute_relro =
._dl_start_profile = _dl_start_profile,
._dl_mcount = _dl_mcount_internal,
._dl_lookup_symbol_x = _dl_lookup_symbol_x,
+ ._dl_check_caller = _dl_check_caller
};
/* If we would use strong_alias here the compiler would see a
non-hidden definition. This would undo the effect of the previous
@@ -208,6 +209,7 @@ static ElfW(Addr) _dl_start_final (void *arg,
/* These defined magically in the linker script. */
extern char _begin[] attribute_hidden;
+extern char _etext[] attribute_hidden;
extern char _end[] attribute_hidden;
@@ -268,6 +270,7 @@ _dl_start_final (void *arg, struct dl_start_final_info *info)
GL(dl_rtld_map).l_opencount = 1;
GL(dl_rtld_map).l_map_start = (ElfW(Addr)) _begin;
GL(dl_rtld_map).l_map_end = (ElfW(Addr)) _end;
+ GL(dl_rtld_map).l_text_end = (ElfW(Addr)) _etext;
/* Copy the TLS related data if necessary. */
#if USE_TLS && !defined DONT_USE_BOOTSTRAP_MAP
# if USE___THREAD
@@ -899,6 +902,7 @@ of this helper program; chances are you did not intend to run this program.\n\
}
GL(dl_loaded)->l_map_end = 0;
+ GL(dl_loaded)->l_text_end = 0;
/* Perhaps the executable has no PT_LOAD header entries at all. */
GL(dl_loaded)->l_map_start = ~0;
/* We opened the file, account for it. */
@@ -969,6 +973,8 @@ of this helper program; chances are you did not intend to run this program.\n\
allocend = GL(dl_loaded)->l_addr + ph->p_vaddr + ph->p_memsz;
if (GL(dl_loaded)->l_map_end < allocend)
GL(dl_loaded)->l_map_end = allocend;
+ if ((ph->p_flags & PF_X) && allocend > GL(dl_loaded)->l_text_end)
+ GL(dl_loaded)->l_text_end = allocend;
}
break;
#ifdef USE_TLS
@@ -1012,6 +1018,8 @@ of this helper program; chances are you did not intend to run this program.\n\
#endif
if (! GL(dl_loaded)->l_map_end)
GL(dl_loaded)->l_map_end = ~0;
+ if (! GL(dl_loaded)->l_text_end)
+ GL(dl_loaded)->l_text_end = ~0;
if (! GL(dl_rtld_map).l_libname && GL(dl_rtld_map).l_name)
{
/* We were invoked directly, so the program might not have a
@@ -1271,11 +1279,15 @@ ERROR: ld.so: object '%s' from %s cannot be preloaded: ignored.\n",
l->l_addr = ph->p_vaddr;
else if (ph->p_vaddr + ph->p_memsz >= l->l_map_end)
l->l_map_end = ph->p_vaddr + ph->p_memsz;
+ else if ((ph->p_flags & PF_X)
+ && ph->p_vaddr + ph->p_memsz >= l->l_text_end)
+ l->l_text_end = ph->p_vaddr + ph->p_memsz;
}
}
l->l_map_start = (ElfW(Addr)) GLRO(dl_sysinfo_dso);
l->l_addr = l->l_map_start - l->l_addr;
l->l_map_end += l->l_addr;
+ l->l_text_end += l->l_addr;
l->l_ld = (void *) ((ElfW(Addr)) l->l_ld + l->l_addr);
elf_get_dynamic_info (l, dyn_temp);
_dl_setup_hash (l);
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 20:49:45 +0000