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-rw-r--r--extra/Configs/Config.in17
-rw-r--r--ldso/include/dl-elf.h2
-rw-r--r--ldso/include/dl-hash.h4
-rw-r--r--ldso/include/ldso.h2
-rw-r--r--ldso/ldso/dl-elf.c37
-rw-r--r--ldso/ldso/dl-startup.c6
-rw-r--r--ldso/ldso/ldso.c128
-rw-r--r--libc/misc/internals/__uClibc_main.c18
8 files changed, 199 insertions, 15 deletions
diff --git a/extra/Configs/Config.in b/extra/Configs/Config.in
index e8d522d71..97211864b 100644
--- a/extra/Configs/Config.in
+++ b/extra/Configs/Config.in
@@ -342,6 +342,23 @@ config LDSO_BASE_FILENAME
WARNING: Changing the default prefix could cause problems with
binutils' ld !
+config LDSO_STANDALONE_SUPPORT
+ bool "Dynamic linker stand-alone mode support"
+ depends on HAVE_SHARED
+ default n
+ help
+ The dynamic linker can be run either indirectly through running some
+ dynamically linked program or library (in which case no command line
+ options to the dynamic linker can be passed and, in the ELF case, the
+ dynamic linker which is stored in the .interp section of the program
+ is executed) or directly by running:
+
+ /lib/ld-uClibc.so.* [OPTIONS] [PROGRAM [ARGUMENTS]]
+
+ Stand-alone execution is a prerequisite for adding prelink
+ capabilities to uClibc dynamic linker, as well useful for testing an
+ updated version of the dynamic linker without breaking the system.
+
config UCLIBC_STATIC_LDCONFIG
bool "Link ldconfig statically"
depends on HAVE_SHARED
diff --git a/ldso/include/dl-elf.h b/ldso/include/dl-elf.h
index cbb2100b1..dc4af7bce 100644
--- a/ldso/include/dl-elf.h
+++ b/ldso/include/dl-elf.h
@@ -35,7 +35,7 @@ extern struct elf_resolve * _dl_load_shared_library(int secure,
struct dyn_elf **rpnt, struct elf_resolve *tpnt, char *full_libname,
int trace_loaded_objects);
extern struct elf_resolve * _dl_load_elf_shared_library(int secure,
- struct dyn_elf **rpnt, char *libname);
+ struct dyn_elf **rpnt, const char *libname);
extern struct elf_resolve *_dl_check_if_named_library_is_loaded(const char *full_libname,
int trace_loaded_objects);
extern int _dl_linux_resolve(void);
diff --git a/ldso/include/dl-hash.h b/ldso/include/dl-hash.h
index 34333f40f..edef9d81b 100644
--- a/ldso/include/dl-hash.h
+++ b/ldso/include/dl-hash.h
@@ -60,6 +60,10 @@ struct elf_resolve {
#endif
ElfW(Addr) mapaddr;
+#ifdef __LDSO_STANDALONE_SUPPORT__
+ /* Store the entry point from the ELF header (e_entry) */
+ ElfW(Addr) l_entry;
+#endif
enum {elf_lib, elf_executable,program_interpreter, loaded_file} libtype;
struct dyn_elf * symbol_scope;
unsigned short usage_count;
diff --git a/ldso/include/ldso.h b/ldso/include/ldso.h
index 69b5dd75a..120889216 100644
--- a/ldso/include/ldso.h
+++ b/ldso/include/ldso.h
@@ -144,7 +144,7 @@ extern void _dl_dprintf(int, const char *, ...);
# define DL_GET_READY_TO_RUN_EXTRA_ARGS
#endif
-extern void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
+extern void *_dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
ElfW(auxv_t) auxvt[AT_EGID + 1], char **envp, char **argv
DL_GET_READY_TO_RUN_EXTRA_PARMS);
diff --git a/ldso/ldso/dl-elf.c b/ldso/ldso/dl-elf.c
index 5562e0784..2a77587db 100644
--- a/ldso/ldso/dl-elf.c
+++ b/ldso/ldso/dl-elf.c
@@ -322,7 +322,7 @@ goof:
*/
struct elf_resolve *_dl_load_elf_shared_library(int secure,
- struct dyn_elf **rpnt, char *libname)
+ struct dyn_elf **rpnt, const char *libname)
{
ElfW(Ehdr) *epnt;
unsigned long dynamic_addr = 0;
@@ -397,11 +397,15 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure,
return NULL;
}
- if ((epnt->e_type != ET_DYN) || (epnt->e_machine != MAGIC1
+ if ((epnt->e_type != ET_DYN
+#ifdef __LDSO_STANDALONE_SUPPORT__
+ && epnt->e_type != ET_EXEC
+#endif
+ ) || (epnt->e_machine != MAGIC1
#ifdef MAGIC2
&& epnt->e_machine != MAGIC2
#endif
- ))
+ ))
{
_dl_internal_error_number =
(epnt->e_type != ET_DYN ? LD_ERROR_NOTDYN : LD_ERROR_NOTMAGIC);
@@ -462,6 +466,11 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure,
ppnt++;
}
+#ifdef __LDSO_STANDALONE_SUPPORT__
+ if (epnt->e_type == ET_EXEC)
+ piclib = 0;
+#endif
+
DL_CHECK_LIB_TYPE (epnt, piclib, _dl_progname, libname);
maxvma = (maxvma + ADDR_ALIGN) & PAGE_ALIGN;
@@ -701,7 +710,11 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure,
dpnt = (ElfW(Dyn) *) dynamic_addr;
_dl_memset(dynamic_info, 0, sizeof(dynamic_info));
+#ifdef __LDSO_STANDALONE_SUPPORT__
+ rtld_flags = _dl_parse_dynamic_info(dpnt, dynamic_info, NULL, piclib ? lib_loadaddr : 0);
+#else
rtld_flags = _dl_parse_dynamic_info(dpnt, dynamic_info, NULL, lib_loadaddr);
+#endif
/* If the TEXTREL is set, this means that we need to make the pages
writable before we perform relocations. Do this now. They get set
back again later. */
@@ -734,6 +747,9 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure,
tpnt->ppnt = (ElfW(Phdr) *) DL_RELOC_ADDR(tpnt->loadaddr, epnt->e_phoff);
tpnt->n_phent = epnt->e_phnum;
tpnt->rtld_flags |= rtld_flags;
+#ifdef __LDSO_STANDALONE_SUPPORT__
+ tpnt->l_entry = epnt->e_entry;
+#endif
#if defined(USE_TLS) && USE_TLS
if (tlsppnt) {
@@ -755,7 +771,11 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure,
tpnt->l_tls_modid = _dl_next_tls_modid ();
/* We know the load address, so add it to the offset. */
+#ifdef __LDSO_STANDALONE_SUPPORT__
+ if ((tpnt->l_tls_initimage != NULL) && piclib)
+#else
if (tpnt->l_tls_initimage != NULL)
+#endif
{
# ifdef __SUPPORT_LD_DEBUG_EARLY__
unsigned int tmp = (unsigned int) tpnt->l_tls_initimage;
@@ -772,7 +792,12 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure,
/*
* Add this object into the symbol chain
*/
- if (*rpnt) {
+ if (*rpnt
+#ifdef __LDSO_STANDALONE_SUPPORT__
+ /* Do not create a new chain entry for the main executable */
+ && (*rpnt)->dyn
+#endif
+ ) {
(*rpnt)->next = _dl_malloc(sizeof(struct dyn_elf));
_dl_memset((*rpnt)->next, 0, sizeof(struct dyn_elf));
(*rpnt)->next->prev = (*rpnt);
@@ -791,7 +816,11 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure,
(*rpnt)->dyn = tpnt;
tpnt->symbol_scope = _dl_symbol_tables;
tpnt->usage_count++;
+#ifdef __LDSO_STANDALONE_SUPPORT__
+ tpnt->libtype = (epnt->e_type == ET_DYN) ? elf_lib : elf_executable;
+#else
tpnt->libtype = elf_lib;
+#endif
/*
* OK, the next thing we need to do is to insert the dynamic linker into
diff --git a/ldso/ldso/dl-startup.c b/ldso/ldso/dl-startup.c
index a51b583a4..2aefa6d74 100644
--- a/ldso/ldso/dl-startup.c
+++ b/ldso/ldso/dl-startup.c
@@ -321,12 +321,12 @@ DL_START(unsigned long args)
__rtld_stack_end = (void *)(argv - 1);
- _dl_get_ready_to_run(tpnt, load_addr, auxvt, envp, argv
- DL_GET_READY_TO_RUN_EXTRA_ARGS);
+ _dl_elf_main = (int (*)(int, char **, char **))
+ _dl_get_ready_to_run(tpnt, (DL_LOADADDR_TYPE) header, auxvt, envp, argv
+ DL_GET_READY_TO_RUN_EXTRA_ARGS);
/* Transfer control to the application. */
SEND_STDERR_DEBUG("transfering control to application @ ");
- _dl_elf_main = (int (*)(int, char **, char **)) auxvt[AT_ENTRY].a_un.a_val;
SEND_ADDRESS_STDERR_DEBUG(_dl_elf_main, 1);
#if !defined(START)
diff --git a/ldso/ldso/ldso.c b/ldso/ldso/ldso.c
index ea4ad0f1c..bb394714f 100644
--- a/ldso/ldso/ldso.c
+++ b/ldso/ldso/ldso.c
@@ -70,8 +70,18 @@ char *_dl_debug_bindings = NULL;
int _dl_debug_file = 2;
#endif
-/* Needed for standalone execution. */
+#if defined (__LDSO_STANDALONE_SUPPORT__) && defined (__sh__)
+/* Not hidden, needed for standalone execution. */
+/*
+ * FIXME: align dl_start for SH to other archs so that we can keep this symbol
+ * hidden and we don't need to handle in __uClibc_main
+ */
+
+unsigned long _dl_skip_args = 0;
+#else
unsigned long attribute_hidden _dl_skip_args = 0;
+#endif
+
const char *_dl_progname = UCLIBC_LDSO; /* The name of the executable being run */
#include "dl-startup.c"
#include "dl-symbols.c"
@@ -274,9 +284,8 @@ static void __attribute__ ((destructor)) __attribute_used__ _dl_fini(void)
}
}
-void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
- ElfW(auxv_t) auxvt[AT_EGID + 1], char **envp,
- char **argv
+void *_dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
+ ElfW(auxv_t) auxvt[AT_EGID + 1], char **envp, char **argv
DL_GET_READY_TO_RUN_EXTRA_PARMS)
{
ElfW(Addr) app_mapaddr = 0;
@@ -327,10 +336,12 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
_dl_progname = argv[0];
}
+#ifndef __LDSO_STANDALONE_SUPPORT__
if (_start == (void *) auxvt[AT_ENTRY].a_un.a_val) {
- _dl_dprintf(_dl_debug_file, "Standalone execution is not supported yet\n");
+ _dl_dprintf(_dl_debug_file, "Standalone execution is not enabled\n");
_dl_exit(1);
}
+#endif
/* Start to build the tables of the modules that are required for
* this beast to run. We start with the basic executable, and then
@@ -382,6 +393,102 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
_dl_init_static_tls = &_dl_nothread_init_static_tls;
#endif
+#ifdef __LDSO_STANDALONE_SUPPORT__
+ if (_start == (void *) auxvt[AT_ENTRY].a_un.a_val) {
+ char *ptmp;
+ unsigned int *aux_dat = (unsigned int *) argv;
+ int argc = aux_dat[-1];
+
+ tpnt->libname = argv[0];
+ while (argc > 1)
+ if (! _dl_strcmp (argv[1], "--library-path") && argc > 2) {
+ _dl_library_path = argv[2];
+ _dl_skip_args += 2;
+ argc -= 2;
+ argv += 2;
+ } else
+ break;
+
+ /*
+ * If we have no further argument the program was called incorrectly.
+ * Grant the user some education.
+ */
+
+ if (argc < 2) {
+ _dl_dprintf(1, "\
+Usage: ld.so [OPTION]... EXECUTABLE-FILE [ARGS-FOR-PROGRAM...]\n\
+You have invoked `ld.so', the helper program for shared library executables.\n\
+This program usually lives in the file `/lib/ld.so', and special directives\n\
+in executable files using ELF shared libraries tell the system's program\n\
+loader to load the helper program from this file. This helper program loads\n\
+the shared libraries needed by the program executable, prepares the program\n\
+to run, and runs it. You may invoke this helper program directly from the\n\
+command line to load and run an ELF executable file; this is like executing\n\
+that file itself, but always uses this helper program from the file you\n\
+specified, instead of the helper program file specified in the executable\n\
+file you run. This is mostly of use for maintainers to test new versions\n\
+of this helper program; chances are you did not intend to run this program.\n\
+\n\
+ --library-path PATH use given PATH instead of content of the environment\n\
+ variable LD_LIBRARY_PATH\n");
+ _dl_exit(1);
+ }
+
+ ++_dl_skip_args;
+ ++argv;
+ _dl_progname = argv[0];
+
+ _dl_symbol_tables = rpnt = _dl_zalloc(sizeof(struct dyn_elf));
+ /*
+ * It needs to load the _dl_progname and to map it
+ * Usually it is the main application launched by means of the ld.so
+ * but it could be also a shared object (when ld.so used for tracing)
+ * We keep the misleading app_tpnt name to avoid variable pollution
+ */
+ app_tpnt = _dl_load_elf_shared_library(_dl_secure, &rpnt, _dl_progname);
+ if (!app_tpnt) {
+ _dl_dprintf(_dl_debug_file, "can't load '%s'\n", _dl_progname);
+ _dl_exit(16);
+ }
+ /*
+ * FIXME: it needs to properly handle a PIE executable
+ * Usually for a main application, loadaddr is computed as difference
+ * between auxvt entry points and phdr, so if it is not 0, that it is a
+ * PIE executable. In this case instead we need to set the loadaddr to 0
+ * because we are actually mapping the ELF for the main application by
+ * ourselves. So the PIE case must be checked.
+ */
+
+ app_tpnt->rtld_flags = unlazy | RTLD_GLOBAL;
+
+ if (app_tpnt->libtype == elf_executable)
+ app_tpnt->loadaddr = 0;
+
+ /*
+ * This is used by gdb to locate the chain of shared libraries that are
+ * currently loaded.
+ */
+ debug_addr = _dl_zalloc(sizeof(struct r_debug));
+ ppnt = (ElfW(Phdr) *)app_tpnt->ppnt;
+ for (i = 0; i < app_tpnt->n_phent; i++, ppnt++) {
+ if (ppnt->p_type == PT_DYNAMIC) {
+ dpnt = (ElfW(Dyn) *) DL_RELOC_ADDR(app_tpnt->loadaddr, ppnt->p_vaddr);
+ _dl_parse_dynamic_info(dpnt, app_tpnt->dynamic_info, debug_addr, app_tpnt->loadaddr);
+ }
+ }
+
+ /* Store the path where the shared lib loader was found
+ * for later use
+ */
+ _dl_ldsopath = _dl_strdup(tpnt->libname);
+ ptmp = _dl_strrchr(_dl_ldsopath, '/');
+ if (ptmp != _dl_ldsopath)
+ *ptmp = '\0';
+
+ _dl_debug_early("Lib Loader: (%x) %s\n", (unsigned) DL_LOADADDR_BASE(tpnt->loadaddr), tpnt->libname);
+ } else {
+#endif
+
/* At this point we are now free to examine the user application,
* and figure out which libraries are supposed to be called. Until
* we have this list, we will not be completely ready for dynamic
@@ -538,6 +645,10 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
}
#endif
+#ifdef __LDSO_STANDALONE_SUPPORT__
+ } /* ! ldso standalone mode */
+#endif
+
#ifdef __SUPPORT_LD_DEBUG__
_dl_debug = _dl_getenv("LD_DEBUG", envp);
if (_dl_debug) {
@@ -1084,6 +1195,13 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
/* Notify the debugger that all objects are now mapped in. */
_dl_debug_addr->r_state = RT_CONSISTENT;
_dl_debug_state();
+
+#ifdef __LDSO_STANDALONE_SUPPORT__
+ if (_start == (void *) auxvt[AT_ENTRY].a_un.a_val)
+ return (void *) app_tpnt->l_entry;
+ else
+#endif
+ return (void *) auxvt[AT_ENTRY].a_un.a_val;
}
#include "dl-hash.c"
diff --git a/libc/misc/internals/__uClibc_main.c b/libc/misc/internals/__uClibc_main.c
index 58f6643b2..36c0c6c63 100644
--- a/libc/misc/internals/__uClibc_main.c
+++ b/libc/misc/internals/__uClibc_main.c
@@ -153,6 +153,10 @@ extern void (*__fini_array_end []) (void) attribute_hidden;
# endif
#endif
+#if defined (__LDSO_STANDALONE_SUPPORT__) && defined (SHARED) && defined __sh__
+extern unsigned long _dl_skip_args;
+#endif
+
attribute_hidden const char *__uclibc_progname = "";
#ifdef __UCLIBC_HAS_PROGRAM_INVOCATION_NAME__
const char *program_invocation_short_name = "";
@@ -341,11 +345,23 @@ void __uClibc_main(int (*main)(int, char **, char **), int argc,
__rtld_fini = rtld_fini;
+#if defined __LDSO_STANDALONE_SUPPORT__ && defined SHARED && defined __sh__
+ /*
+ * Skip ld.so and its arguments
+ * Other archs except for SH do this in _dl_start before passing
+ * control to the application.
+ * FIXME: align SH _dl_start to other archs and remove this from here,
+ * so that we can keep the visibility hidden.
+ */
+ argc -= _dl_skip_args;
+ argv += _dl_skip_args;
+#endif
+
/* The environment begins right after argv. */
__environ = &argv[argc + 1];
/* If the first thing after argv is the arguments
- * the the environment is empty. */
+ * then the environment is empty. */
if ((char *) __environ == *argv) {
/* Make __environ point to the NULL at argv[argc] */
__environ = &argv[argc];
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-17 21:33:05 +0000