From f5108ce0c0f72a285e4cb198426e477295c84517 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Timo=20Ter=C3=A4s?= Date: Tue, 8 Jan 2013 11:55:26 +0200 Subject: [PATCH] dl: fix dlsym lookups with RTLD_NEXT MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The current code for dlsym() when invoked with RTLD_NEXT lookup searches for the module where it's being called from, and executes the _dl_find_hash only for the next module in the chain. However, if the looked symbol is not there, the rest of the modules are not checked. Generally this is not a problem as symbols are merged for the parent modules; so this affects only RTLD_NEXT. This patch adds a loop iterating through all the following modules. Signed-off-by: Timo Teräs Reviewed-by: Filippo ARCIDIACONO Tested-by: Florian Fainelli Signed-off-by: Bernhard Reutner-Fischer --- ldso/libdl/libdl.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/ldso/libdl/libdl.c b/ldso/libdl/libdl.c index 51bcf7d..71ade1f 100644 --- a/ldso/libdl/libdl.c +++ b/ldso/libdl/libdl.c @@ -671,7 +671,7 @@ static void *do_dlsym(void *vhandle, const char *name, void *caller_address) { struct elf_resolve *tpnt, *tfrom; struct dyn_elf *handle; - ElfW(Addr) from; + ElfW(Addr) from = 0; struct dyn_elf *rpnt; void *ret; struct symbol_ref sym_ref = { NULL, NULL }; @@ -729,7 +729,13 @@ static void *do_dlsym(void *vhandle, const char *name, void *caller_address) tpnt = NULL; if (handle == _dl_symbol_tables) tpnt = handle->dyn; /* Only search RTLD_GLOBAL objs if global object */ - ret = _dl_find_hash(name2, &handle->dyn->symbol_scope, tpnt, ELF_RTYPE_CLASS_DLSYM, &sym_ref); + + do { + ret = _dl_find_hash(name2, &handle->dyn->symbol_scope, tpnt, ELF_RTYPE_CLASS_DLSYM, &sym_ref); + if (ret != NULL) + break; + handle = handle->next; + } while (from && handle); #if defined(USE_TLS) && USE_TLS && defined SHARED if (sym_ref.sym && (ELF_ST_TYPE(sym_ref.sym->st_info) == STT_TLS) && (sym_ref.tpnt)) { -- 1.7.10.4