[git commit] libdl: fix dlopen implementation from statically linked application

Carmelo Amoroso carmelo.amoroso at st.com
Mon May 13 08:11:21 UTC 2013


commit: http://git.uclibc.org/uClibc/commit/?id=231e4a9b4b972662a6832f714a05525a3754892d
branch: http://git.uclibc.org/uClibc/commit/?id=refs/heads/master

Calling dlopen from statically linked application is actually broken,
because _dl_find_hash enters into an infinite loop when trying to
resolve symbols. In this case it doesn't need to extend the global
scope, it is readyto be used as it is, because _dl_loaded_modules already points
to the dlopened library.

The patch also fixesi a typo in __LDSO_LD_LIBRARY_PATH__ macro, that was
preventing to get the actual value of the LD_LIBRARY_PATH.

Signed-off-by: Filippo Arcidiacono <filippo.arcidiacono at st.com>
Signed-off-by: Carmelo Amoroso <carmelo.amoroso at st.com>
---
 ldso/libdl/libdl.c |   11 +++++++++--
 1 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/ldso/libdl/libdl.c b/ldso/libdl/libdl.c
index 4630a59..3a78696 100644
--- a/ldso/libdl/libdl.c
+++ b/ldso/libdl/libdl.c
@@ -374,7 +374,7 @@ static void *do_dlopen(const char *libname, int flag, ElfW(Addr) from)
 	if (getenv("LD_BIND_NOW"))
 		now_flag = RTLD_NOW;
 
-#if !defined SHARED && defined __LDSO_LIBRARY_PATH__
+#if !defined SHARED && defined __LDSO_LD_LIBRARY_PATH__
 	/* When statically linked, the _dl_library_path is not yet initialized */
 	_dl_library_path = getenv("LD_LIBRARY_PATH");
 #endif
@@ -541,11 +541,18 @@ static void *do_dlopen(const char *libname, int flag, ElfW(Addr) from)
 	 * to the GOT tables.  We need to do this in reverse order so that COPY
 	 * directives work correctly */
 
-	/* Get the tail of the list */
+#ifdef SHARED
+	/*
+	 * Get the tail of the list.
+	 * In the static case doesn't need to extend the global scope, it is
+	 * ready to be used as it is, because _dl_loaded_modules already points
+	 * to the dlopened library.
+	 */
 	for (ls = &_dl_loaded_modules->symbol_scope; ls && ls->next; ls = ls->next);
 
 	/* Extend the global scope by adding the local scope of the dlopened DSO. */
 	ls->next = &dyn_chain->dyn->symbol_scope;
+#endif
 #ifdef __mips__
 	/*
 	 * Relocation of the GOT entries for MIPS have to be done


More information about the uClibc-cvs mailing list