From d869bb1600942c01a77539128f9ba5b5b55ad647 Mon Sep 17 00:00:00 2001 From: ramin Date: Wed, 7 Dec 2022 11:59:57 +0100 Subject: add getauxval() implementation --- ldso/include/ldso.h | 8 +++++++- ldso/ldso/dl-startup.c | 32 +++++++++++++++++++++----------- ldso/ldso/ldso.c | 47 +++++++++++++++++++++++------------------------ 3 files changed, 51 insertions(+), 36 deletions(-) mode change 100644 => 100755 ldso/include/ldso.h mode change 100644 => 100755 ldso/ldso/ldso.c (limited to 'ldso') diff --git a/ldso/include/ldso.h b/ldso/include/ldso.h old mode 100644 new mode 100755 index f19957d1d..c035b3b52 --- a/ldso/include/ldso.h +++ b/ldso/include/ldso.h @@ -148,6 +148,7 @@ extern int _dl_debug_file; #define NULL ((void *) 0) #endif + extern void *_dl_malloc(size_t size); extern void *_dl_calloc(size_t __nmemb, size_t __size); extern void *_dl_realloc(void *__ptr, size_t __size); @@ -176,7 +177,7 @@ extern void _dl_dprintf(int, const char *, ...); #endif 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 + char **envp, char **argv DL_GET_READY_TO_RUN_EXTRA_PARMS); #ifdef HAVE_DL_INLINES_H @@ -185,6 +186,11 @@ extern void *_dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE loa #else /* __ARCH_HAS_NO_SHARED__ */ #include +#include + #endif +#define AUX_MAX_AT_ID 40 +extern ElfW(auxv_t) _dl_auxvt[AUX_MAX_AT_ID]; + #endif /* _LDSO_H */ diff --git a/ldso/ldso/dl-startup.c b/ldso/ldso/dl-startup.c index a1b3d49fd..e36d688b4 100644 --- a/ldso/ldso/dl-startup.c +++ b/ldso/ldso/dl-startup.c @@ -98,6 +98,9 @@ extern ElfW(Addr) _begin[] attribute_hidden; #endif + +ElfW(auxv_t) _dl_auxvt[AUX_MAX_AT_ID]; + #ifdef LDSO_NEED_DPNT ElfW(Dyn) *_dl_saved_dpnt = 0; #endif @@ -127,7 +130,7 @@ DL_START(unsigned long args) ElfW(Ehdr) *header; struct elf_resolve tpnt_tmp; struct elf_resolve *tpnt = &tpnt_tmp; - ElfW(auxv_t) auxvt[AT_EGID + 1]; + ElfW(auxv_t) _dl_auxvt_tmp[AUX_MAX_AT_ID]; ElfW(Dyn) *dpnt; uint32_t *p32; @@ -158,7 +161,7 @@ DL_START(unsigned long args) /* Place -1 here as a checkpoint. We later check if it was changed * when we read in the auxvt */ - auxvt[AT_UID].a_type = -1; + _dl_auxvt_tmp[AT_UID].a_type = -1; /* The junk on the stack immediately following the environment is * the Auxiliary Vector Table. Read out the elements of the auxvt, @@ -166,9 +169,11 @@ DL_START(unsigned long args) while (*aux_dat) { ElfW(auxv_t) *auxv_entry = (ElfW(auxv_t) *) aux_dat; - if (auxv_entry->a_type <= AT_EGID) { - _dl_memcpy(&(auxvt[auxv_entry->a_type]), auxv_entry, sizeof(ElfW(auxv_t))); + if (auxv_entry->a_type < AUX_MAX_AT_ID) { + _dl_memcpy(&(_dl_auxvt_tmp[auxv_entry->a_type]), auxv_entry, sizeof(ElfW(auxv_t))); } + + aux_dat += 2; } @@ -183,16 +188,16 @@ DL_START(unsigned long args) * We use it if the kernel is not passing a valid address through the auxvt. */ - if (!auxvt[AT_BASE].a_un.a_val) - auxvt[AT_BASE].a_un.a_val = (ElfW(Addr)) &_begin; + if (!_dl_auxvt_tmp[AT_BASE].a_un.a_val) + _dl_auxvt_tmp[AT_BASE].a_un.a_val = (ElfW(Addr)) &_begin; /* Note: if the dynamic linker itself is prelinked, the load_addr is 0 */ DL_INIT_LOADADDR_BOOT(load_addr, elf_machine_load_address()); #else - if (!auxvt[AT_BASE].a_un.a_val) - auxvt[AT_BASE].a_un.a_val = elf_machine_load_address(); - DL_INIT_LOADADDR_BOOT(load_addr, auxvt[AT_BASE].a_un.a_val); + if (!_dl_auxvt_tmp[AT_BASE].a_un.a_val) + _dl_auxvt_tmp[AT_BASE].a_un.a_val = elf_machine_load_address(); + DL_INIT_LOADADDR_BOOT(load_addr, _dl_auxvt_tmp[AT_BASE].a_un.a_val); #endif - header = (ElfW(Ehdr) *) auxvt[AT_BASE].a_un.a_val; + header = (ElfW(Ehdr) *) _dl_auxvt_tmp[AT_BASE].a_un.a_val; /* Check the ELF header to make sure everything looks ok. */ if (!header || header->e_ident[EI_CLASS] != ELF_CLASS || @@ -353,8 +358,13 @@ DL_START(unsigned long args) #endif __rtld_stack_end = (void *)(argv - 1); + /* + * now the globals work. so copy the aux vector + */ + _dl_memcpy( _dl_auxvt, _dl_auxvt_tmp, sizeof( ElfW(auxv_t) ) * AUX_MAX_AT_ID ); + _dl_elf_main = (int (*)(int, char **, char **)) - _dl_get_ready_to_run(tpnt, load_addr, auxvt, envp, argv + _dl_get_ready_to_run(tpnt, load_addr, envp, argv DL_GET_READY_TO_RUN_EXTRA_ARGS); /* Transfer control to the application. */ diff --git a/ldso/ldso/ldso.c b/ldso/ldso/ldso.c old mode 100644 new mode 100755 index b33547670..8e4914df5 --- a/ldso/ldso/ldso.c +++ b/ldso/ldso/ldso.c @@ -350,10 +350,9 @@ static void trace_objects(struct elf_resolve *tpnt, char *str_name) static struct elf_resolve * add_ldso(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr, ElfW(Addr) ldso_mapaddr, - ElfW(auxv_t) auxvt[AT_EGID + 1], struct dyn_elf *rpnt) { - ElfW(Ehdr) *epnt = (ElfW(Ehdr) *) auxvt[AT_BASE].a_un.a_val; + ElfW(Ehdr) *epnt = (ElfW(Ehdr) *) _dl_auxvt[AT_BASE].a_un.a_val; ElfW(Phdr) *myppnt = (ElfW(Phdr) *) DL_RELOC_ADDR(DL_GET_RUN_ADDR(load_addr, ldso_mapaddr), epnt->e_phoff); @@ -422,7 +421,7 @@ static void _dl_setup_progname(const char *argv0) } 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 + char **envp, char **argv DL_GET_READY_TO_RUN_EXTRA_PARMS) { ElfW(Addr) app_mapaddr = 0, ldso_mapaddr = 0; @@ -461,7 +460,7 @@ void *_dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr, _dl_memset(app_tpnt, 0, sizeof(*app_tpnt)); /* Store the page size for later use */ - _dl_pagesize = (auxvt[AT_PAGESZ].a_un.a_val) ? (size_t) auxvt[AT_PAGESZ].a_un.a_val : PAGE_SIZE; + _dl_pagesize = (_dl_auxvt[AT_PAGESZ].a_un.a_val) ? (size_t) _dl_auxvt[AT_PAGESZ].a_un.a_val : PAGE_SIZE; /* Make it so _dl_malloc can use the page of memory we have already * allocated. We shouldn't need to grab any more memory. This must * be first since things like _dl_dprintf() use _dl_malloc()... @@ -485,7 +484,7 @@ void *_dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr, #endif #ifndef __LDSO_STANDALONE_SUPPORT__ - if (_start == (void *) auxvt[AT_ENTRY].a_un.a_val) { + if (_start == (void *) _dl_auxvt[AT_ENTRY].a_un.a_val) { _dl_dprintf(2, "Standalone execution is not enabled\n"); _dl_exit(1); } @@ -504,10 +503,10 @@ void *_dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr, * Note that for SUID programs we ignore the settings in * LD_LIBRARY_PATH. */ - if ((auxvt[AT_UID].a_un.a_val == (size_t)-1 && _dl_suid_ok()) || - (auxvt[AT_UID].a_un.a_val != (size_t)-1 && - auxvt[AT_UID].a_un.a_val == auxvt[AT_EUID].a_un.a_val && - auxvt[AT_GID].a_un.a_val == auxvt[AT_EGID].a_un.a_val)) { + if ((_dl_auxvt[AT_UID].a_un.a_val == (size_t)-1 && _dl_suid_ok()) || + (_dl_auxvt[AT_UID].a_un.a_val != (size_t)-1 && + _dl_auxvt[AT_UID].a_un.a_val == _dl_auxvt[AT_EUID].a_un.a_val && + _dl_auxvt[AT_GID].a_un.a_val == _dl_auxvt[AT_EGID].a_un.a_val)) { _dl_secure = 0; #ifdef __LDSO_PRELOAD_ENV_SUPPORT__ _dl_preload = _dl_getenv("LD_PRELOAD", envp); @@ -546,7 +545,7 @@ void *_dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr, #endif #ifdef __LDSO_STANDALONE_SUPPORT__ - if (_start == (void *) auxvt[AT_ENTRY].a_un.a_val) { + if (_start == (void *) _dl_auxvt[AT_ENTRY].a_un.a_val) { ElfW(Addr) *aux_dat = (ElfW(Addr) *) argv; int argc = (int) aux_dat[-1]; @@ -643,11 +642,11 @@ of this helper program; chances are you did not intend to run this program.\n\ */ { unsigned int idx; - ElfW(Phdr) *phdr = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val; + ElfW(Phdr) *phdr = (ElfW(Phdr) *) _dl_auxvt[AT_PHDR].a_un.a_val; - for (idx = 0; idx < auxvt[AT_PHNUM].a_un.a_val; idx++, phdr++) + for (idx = 0; idx < _dl_auxvt[AT_PHNUM].a_un.a_val; idx++, phdr++) if (phdr->p_type == PT_PHDR) { - DL_INIT_LOADADDR_PROG(app_tpnt->loadaddr, auxvt[AT_PHDR].a_un.a_val - phdr->p_vaddr); + DL_INIT_LOADADDR_PROG(app_tpnt->loadaddr, _dl_auxvt[AT_PHDR].a_un.a_val - phdr->p_vaddr); break; } @@ -662,8 +661,8 @@ of this helper program; chances are you did not intend to run this program.\n\ */ debug_addr = _dl_zalloc(sizeof(struct r_debug)); - ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val; - for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) { + ppnt = (ElfW(Phdr) *) _dl_auxvt[AT_PHDR].a_un.a_val; + for (i = 0; i < _dl_auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) { if (ppnt->p_type == PT_GNU_RELRO) { relro_addr = ppnt->p_vaddr; relro_size = ppnt->p_memsz; @@ -685,8 +684,8 @@ of this helper program; chances are you did not intend to run this program.\n\ int j; ElfW(Phdr) *ppnt_outer = ppnt; _dl_debug_early("calling mprotect on the application program\n"); - ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val; - for (j = 0; j < auxvt[AT_PHNUM].a_un.a_val; j++, ppnt++) { + ppnt = (ElfW(Phdr) *) _dl_auxvt[AT_PHDR].a_un.a_val; + for (j = 0; j < _dl_auxvt[AT_PHNUM].a_un.a_val; j++, ppnt++) { if (ppnt->p_type == PT_LOAD && !(ppnt->p_flags & PF_W)) _dl_mprotect((void *) (DL_RELOC_ADDR(app_tpnt->loadaddr, ppnt->p_vaddr) & PAGE_ALIGN), (DL_RELOC_ADDR(app_tpnt->loadaddr, ppnt->p_vaddr) & ADDR_ALIGN) + @@ -713,8 +712,8 @@ of this helper program; chances are you did not intend to run this program.\n\ (unsigned long) DL_RELOC_ADDR(app_tpnt->loadaddr, ppnt->p_vaddr), ppnt->p_filesz); _dl_loaded_modules->libtype = elf_executable; - _dl_loaded_modules->ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val; - _dl_loaded_modules->n_phent = auxvt[AT_PHNUM].a_un.a_val; + _dl_loaded_modules->ppnt = (ElfW(Phdr) *) _dl_auxvt[AT_PHDR].a_un.a_val; + _dl_loaded_modules->n_phent = _dl_auxvt[AT_PHNUM].a_un.a_val; _dl_symbol_tables = rpnt = _dl_zalloc(sizeof(struct dyn_elf)); rpnt->dyn = _dl_loaded_modules; app_tpnt->mapaddr = app_mapaddr; @@ -856,7 +855,7 @@ of this helper program; chances are you did not intend to run this program.\n\ } #endif - ldso_mapaddr = (ElfW(Addr)) auxvt[AT_BASE].a_un.a_val; + ldso_mapaddr = (ElfW(Addr)) _dl_auxvt[AT_BASE].a_un.a_val; /* * OK, fix one more thing - set up debug_addr so it will point * to our chain. Later we may need to fill in more fields, but this @@ -1046,7 +1045,7 @@ of this helper program; chances are you did not intend to run this program.\n\ if (!ldso_tpnt) { /* Insert the ld.so only once */ ldso_tpnt = add_ldso(tpnt, load_addr, - ldso_mapaddr, auxvt, rpnt); + ldso_mapaddr, rpnt); } else { ldso_tpnt->init_flag |= DL_OPENED2; } @@ -1148,7 +1147,7 @@ of this helper program; chances are you did not intend to run this program.\n\ * again once all libs are loaded. */ if (!ldso_tpnt) { - tpnt = add_ldso(tpnt, load_addr, ldso_mapaddr, auxvt, rpnt); + tpnt = add_ldso(tpnt, load_addr, ldso_mapaddr, rpnt); tpnt->usage_count++; nscope_elem++; } else @@ -1450,11 +1449,11 @@ of this helper program; chances are you did not intend to run this program.\n\ _dl_debug_state(); #ifdef __LDSO_STANDALONE_SUPPORT__ - if (_start == (void *) auxvt[AT_ENTRY].a_un.a_val) + if (_start == (void *) _dl_auxvt[AT_ENTRY].a_un.a_val) return (void *) app_tpnt->l_entry; else #endif - return (void *) auxvt[AT_ENTRY].a_un.a_val; + return (void *) _dl_auxvt[AT_ENTRY].a_un.a_val; } #include "dl-hash.c" -- cgit v1.2.3