From 24acea547572659fd2041803882411b68ff0d6eb Mon Sep 17 00:00:00 2001 From: Joakim Tjernlund Date: Sat, 17 Sep 2005 17:06:59 +0000 Subject: Fix bug 430 and reduce ldso size with 1KB :). Not sure if I need to use fstat64, but I am sure someone will tell me. --- ldso/include/dl-hash.h | 3 ++ ldso/include/dl-syscall.h | 7 ++- ldso/ldso/dl-elf.c | 133 +++++++++------------------------------------- 3 files changed, 34 insertions(+), 109 deletions(-) diff --git a/ldso/include/dl-hash.h b/ldso/include/dl-hash.h index af6c2b93f..00b9c87f6 100644 --- a/ldso/include/dl-hash.h +++ b/ldso/include/dl-hash.h @@ -49,6 +49,9 @@ struct elf_resolve{ ElfW(Addr) relro_addr; size_t relro_size; + dev_t st_dev; /* device */ + ino_t st_ino; /* inode */ + #ifdef __powerpc__ /* this is used to store the address of relocation data words, so * we don't have to calculate it every time, which requires a divide */ diff --git a/ldso/include/dl-syscall.h b/ldso/include/dl-syscall.h index 3f20229cd..a1a2859c4 100644 --- a/ldso/include/dl-syscall.h +++ b/ldso/include/dl-syscall.h @@ -11,7 +11,9 @@ #define kernel_stat stat #include #include - +#define _SYSCALL_H +#include +#undef _SYSCALL_H /* _dl_open() parameters */ #define O_RDONLY 0x0000 @@ -82,6 +84,9 @@ static inline _syscall3(int, _dl_mprotect, const void *, addr, unsigned long, le #define __NR__dl_stat __NR_stat static inline _syscall2(int, _dl_stat, const char *, file_name, struct stat *, buf); +#define __NR__dl_fstat __NR_fstat +static inline _syscall2(int, _dl_fstat, int, fd, struct stat *, buf); + #define __NR__dl_munmap __NR_munmap static inline _syscall2(int, _dl_munmap, void *, start, unsigned long, length); diff --git a/ldso/ldso/dl-elf.c b/ldso/ldso/dl-elf.c index 14a10bc1f..28b3094d1 100644 --- a/ldso/ldso/dl-elf.c +++ b/ldso/ldso/dl-elf.c @@ -180,71 +180,6 @@ search_for_named_library(const char *name, int secure, const char *path_list, return NULL; } -/* Check if the named library is already loaded... */ -struct elf_resolve *_dl_check_if_named_library_is_loaded(const char *full_libname, - int trace_loaded_objects) -{ - const char *pnt, *pnt1; - struct elf_resolve *tpnt1; - const char *libname, *libname2; - static const char libc[] = "libc.so."; - static const char aborted_wrong_lib[] = "%s: aborted attempt to load %s!\n"; - - pnt = libname = full_libname; - - _dl_if_debug_dprint("Checking if '%s' is already loaded\n", full_libname); - /* quick hack to ensure mylibname buffer doesn't overflow. don't - allow full_libname or any directory to be longer than 1024. */ - if (_dl_strlen(full_libname) > 1024) - return NULL; - - /* Skip over any initial initial './' and '/' stuff to - * get the short form libname with no path garbage */ - pnt1 = _dl_strrchr(pnt, '/'); - if (pnt1) { - libname = pnt1 + 1; - } - - /* Make sure they are not trying to load the wrong C library! - * This sometimes happens esp with shared libraries when the - * library path is somehow wrong! */ -#define isdigit(c) (c >= '0' && c <= '9') - if ((_dl_strncmp(libname, libc, 8) == 0) && _dl_strlen(libname) >=8 && - isdigit(libname[8])) - { - /* Abort attempts to load glibc, libc5, etc */ - if ( libname[8]!='0') { - if (!trace_loaded_objects) { - _dl_dprintf(2, aborted_wrong_lib, libname, _dl_progname); - _dl_exit(1); - } - return NULL; - } - } - - /* Critical step! Weed out duplicates early to avoid - * function aliasing, which wastes memory, and causes - * really bad things to happen with weaks and globals. */ - for (tpnt1 = _dl_loaded_modules; tpnt1; tpnt1 = tpnt1->next) { - - /* Skip over any initial initial './' and '/' stuff to - * get the short form libname with no path garbage */ - libname2 = tpnt1->libname; - pnt1 = _dl_strrchr(libname2, '/'); - if (pnt1) { - libname2 = pnt1 + 1; - } - - if (_dl_strcmp(libname2, libname) == 0) { - /* Well, that was certainly easy */ - return tpnt1; - } - } - - return NULL; -} - - /* Used to return error codes back to dlopen et. al. */ unsigned long _dl_error_number; unsigned long _dl_internal_error_number; @@ -271,14 +206,6 @@ struct elf_resolve *_dl_load_shared_library(int secure, struct dyn_elf **rpnt, libname = pnt + 1; } - /* Critical step! Weed out duplicates early to avoid - * function aliasing, which wastes memory, and causes - * really bad things to happen with weaks and globals. */ - if ((tpnt1=_dl_check_if_named_library_is_loaded(libname, trace_loaded_objects))!=NULL) { - tpnt1->usage_count++; - return tpnt1; - } - _dl_if_debug_dprint("\tfind library='%s'; searching\n", libname); /* If the filename has any '/', try it straight and leave it at that. For IBCS2 compatibility under linux, we substitute the string @@ -290,7 +217,6 @@ struct elf_resolve *_dl_load_shared_library(int secure, struct dyn_elf **rpnt, if (tpnt1) { return tpnt1; } - //goto goof; } /* @@ -411,48 +337,37 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure, int i, flags, piclib, infile; ElfW(Addr) relro_addr = 0; size_t relro_size = 0; - - /* If this file is already loaded, skip this step */ - tpnt = _dl_check_hashed_files(libname); - if (tpnt) { - if (*rpnt) { - (*rpnt)->next = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf)); - _dl_memset((*rpnt)->next, 0, sizeof(struct dyn_elf)); - (*rpnt)->next->prev = (*rpnt); - *rpnt = (*rpnt)->next; - (*rpnt)->dyn = tpnt; - tpnt->symbol_scope = _dl_symbol_tables; - } - tpnt->usage_count++; - tpnt->libtype = elf_lib; - _dl_if_debug_dprint("file='%s'; already loaded\n", libname); - return tpnt; - } - - /* If we are in secure mode (i.e. a setu/gid binary using LD_PRELOAD), - we don't load the library if it isn't setuid. */ - - if (secure) { - struct stat st; - - if (_dl_stat(libname, &st) || !(st.st_mode & S_ISUID)) - return NULL; - } + struct stat st; libaddr = 0; infile = _dl_open(libname, O_RDONLY, 0); if (infile < 0) { -#if 0 - /* - * NO! When we open shared libraries we may search several paths. - * it is inappropriate to generate an error here. - */ - _dl_dprintf(2, "%s: can't open '%s'\n", _dl_progname, libname); -#endif _dl_internal_error_number = LD_ERROR_NOFILE; return NULL; } + if (_dl_fstat(infile, &st) < 0) { + _dl_internal_error_number = LD_ERROR_NOFILE; + _dl_close(infile); + return NULL; + } + /* If we are in secure mode (i.e. a setu/gid binary using LD_PRELOAD), + we don't load the library if it isn't setuid. */ + if (secure) + if (!(st.st_mode & S_ISUID)) { + _dl_close(infile); + return NULL; + } + + /* Check if file is already loaded */ + for (tpnt = _dl_loaded_modules; tpnt; tpnt = tpnt->next) { + if(tpnt->st_dev == st.st_dev && tpnt->st_ino == st.st_ino) { + /* Already loaded */ + tpnt->usage_count++; + _dl_close(infile); + return tpnt; + } + } header = _dl_mmap((void *) 0, _dl_pagesize, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); if (_dl_mmap_check_error(header)) { @@ -665,6 +580,8 @@ struct elf_resolve *_dl_load_elf_shared_library(int secure, dynamic_addr, 0); tpnt->relro_addr = relro_addr; tpnt->relro_size = relro_size; + tpnt->st_dev = st.st_dev; + tpnt->st_ino = st.st_ino; tpnt->ppnt = (ElfW(Phdr) *)(intptr_t) (tpnt->loadaddr + epnt->e_phoff); tpnt->n_phent = epnt->e_phnum; -- cgit v1.2.3