From 0ba7ee452f26088f6b738c37e05c16c7c9eb1caf Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Timo=20Ter=C3=A4s?= Date: Fri, 18 Mar 2011 10:53:56 +0200 Subject: [PATCH 1/3] ldso: limited support for $ORIGIN in rpath MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Handle it if it's in the beginning of the rpath entry as it should be. Signed-off-by: Timo Teräs --- ldso/ldso/dl-elf.c | 80 ++++++++++++++++++++++++++++----------------------- ldso/ldso/ldso.c | 18 ++++++++++-- 2 files changed, 59 insertions(+), 39 deletions(-) diff --git a/ldso/ldso/dl-elf.c b/ldso/ldso/dl-elf.c index 505247e..2b2d429 100644 --- a/ldso/ldso/dl-elf.c +++ b/ldso/ldso/dl-elf.c @@ -133,53 +133,60 @@ _dl_protect_relro (struct elf_resolve *l) * in uClibc/ldso/util/ldd.c */ static struct elf_resolve * search_for_named_library(const char *name, int secure, const char *path_list, - struct dyn_elf **rpnt) + struct dyn_elf **rpnt, const char *origin) { - char *path, *path_n, *mylibname; + char *mylibname; + const char *p, *pn; struct elf_resolve *tpnt; - int done; + int plen; if (path_list==NULL) return NULL; - /* We need a writable copy of this string, but we don't - * need this allocated permanently since we don't want - * to leak memory, so use alloca to put path on the stack */ - done = _dl_strlen(path_list); - path = alloca(done + 1); - /* another bit of local storage */ mylibname = alloca(2050); - _dl_memcpy(path, path_list, done+1); - /* Unlike ldd.c, don't bother to eliminate double //s */ /* Replace colons with zeros in path_list */ /* : at the beginning or end of path maps to CWD */ /* :: anywhere maps CWD */ /* "" maps to CWD */ - done = 0; - path_n = path; - do { - if (*path == 0) { - *path = ':'; - done = 1; - } - if (*path == ':') { - *path = 0; - if (*path_n) - _dl_strcpy(mylibname, path_n); - else - _dl_strcpy(mylibname, "."); /* Assume current dir if empty path */ - _dl_strcat(mylibname, "/"); - _dl_strcat(mylibname, name); - if ((tpnt = _dl_load_elf_shared_library(secure, rpnt, mylibname)) != NULL) - return tpnt; - path_n = path+1; + for (p = path_list; p != NULL; p = pn) { + pn = _dl_strchr(p + 1, ':'); + if (pn != NULL) { + plen = pn - p; + pn++; + } else + plen = _dl_strlen(p); + + if (plen >= 7 && _dl_memcmp(p, "$ORIGIN", 7) == 0) { + int olen; + if (secure && plen != 7) + continue; + if (origin == NULL) + continue; + for (olen = _dl_strlen(origin) - 1; olen >= 0 && origin[olen] != '/'; olen--) + ; + if (olen <= 0) + continue; + _dl_memcpy(&mylibname[0], origin, olen); + _dl_memcpy(&mylibname[olen], p + 7, plen - 7); + mylibname[olen + plen - 7] = 0; + } else if (plen != 0) { + _dl_memcpy(mylibname, p, plen); + mylibname[plen] = 0; + } else { + _dl_strcpy(mylibname, "."); } - path++; - } while (!done); + _dl_strcat(mylibname, "/"); + _dl_strcat(mylibname, name); + + tpnt = _dl_load_elf_shared_library(secure, rpnt, mylibname); + if (tpnt != NULL) + return tpnt; + } + return NULL; } @@ -231,7 +238,8 @@ struct elf_resolve *_dl_load_shared_library(int secure, struct dyn_elf **rpnt, if (pnt) { pnt += (unsigned long) tpnt->dynamic_info[DT_STRTAB]; _dl_if_debug_dprint("\tsearching RPATH='%s'\n", pnt); - if ((tpnt1 = search_for_named_library(libname, secure, pnt, rpnt)) != NULL) + if ((tpnt1 = search_for_named_library(libname, secure, pnt, rpnt, + tpnt->libname)) != NULL) return tpnt1; } #endif @@ -239,7 +247,7 @@ struct elf_resolve *_dl_load_shared_library(int secure, struct dyn_elf **rpnt, /* Check in LD_{ELF_}LIBRARY_PATH, if specified and allowed */ if (_dl_library_path) { _dl_if_debug_dprint("\tsearching LD_LIBRARY_PATH='%s'\n", _dl_library_path); - if ((tpnt1 = search_for_named_library(libname, secure, _dl_library_path, rpnt)) != NULL) + if ((tpnt1 = search_for_named_library(libname, secure, _dl_library_path, rpnt, NULL)) != NULL) { return tpnt1; } @@ -253,7 +261,7 @@ struct elf_resolve *_dl_load_shared_library(int secure, struct dyn_elf **rpnt, if (pnt) { pnt += (unsigned long) tpnt->dynamic_info[DT_STRTAB]; _dl_if_debug_dprint("\tsearching RUNPATH='%s'\n", pnt); - if ((tpnt1 = search_for_named_library(libname, secure, pnt, rpnt)) != NULL) + if ((tpnt1 = search_for_named_library(libname, secure, pnt, rpnt, NULL)) != NULL) return tpnt1; } #endif @@ -287,7 +295,7 @@ struct elf_resolve *_dl_load_shared_library(int secure, struct dyn_elf **rpnt, /* Look for libraries wherever the shared library loader * was installed */ _dl_if_debug_dprint("\tsearching ldso dir='%s'\n", _dl_ldsopath); - tpnt1 = search_for_named_library(libname, secure, _dl_ldsopath, rpnt); + tpnt1 = search_for_named_library(libname, secure, _dl_ldsopath, rpnt, NULL); if (tpnt1 != NULL) return tpnt1; @@ -300,7 +308,7 @@ struct elf_resolve *_dl_load_shared_library(int secure, struct dyn_elf **rpnt, #ifndef __LDSO_CACHE_SUPPORT__ ":" UCLIBC_RUNTIME_PREFIX "usr/X11R6/lib" #endif - , rpnt); + , rpnt, NULL); if (tpnt1 != NULL) return tpnt1; diff --git a/ldso/ldso/ldso.c b/ldso/ldso/ldso.c index 7ee9257..9423670 100644 --- a/ldso/ldso/ldso.c +++ b/ldso/ldso/ldso.c @@ -272,6 +272,20 @@ static void __attribute__ ((destructor)) __attribute_used__ _dl_fini(void) } } +static void _dl_setup_progname(const char *argv0) +{ + char image[PATH_MAX]; + ssize_t s; + + s = _dl_readlink("/proc/self/exe", image, sizeof(image)); + if (s > 0 && image[0] == '/') { + image[s] = 0; + _dl_progname = _dl_strdup(image); + } else if (argv0) { + _dl_progname = 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 @@ -321,9 +335,7 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr, * been fixed up by now. Still no function calls outside of this * library, since the dynamic resolver is not yet ready. */ - if (argv[0]) { - _dl_progname = argv[0]; - } + _dl_setup_progname(argv[0]); if (_start == (void *) auxvt[AT_ENTRY].a_un.a_val) { _dl_dprintf(_dl_debug_file, "Standalone execution is not supported yet\n"); -- 1.7.1