svn commit: r313494 - head/libexec/rtld-elf

[Konstantin Belousov]

Author: kib
Date: Thu Feb  9 23:33:06 2017
New Revision: 313494
URL: https://svnweb.freebsd.org/changeset/base/313494

Log:
  Handle protected symbols in rtld.
  
  Protected symbol reference in GOT of the defining object must be
  resolved to itself, same as -Bsymbolic globally.
  
  Discussed with:	emaste
  Sponsored by:	The FreeBSD Foundation
  MFC after:	2 weeks
  Differential revision:	https://reviews.freebsd.org/D9317

Modified:
  head/libexec/rtld-elf/rtld.c

Modified: head/libexec/rtld-elf/rtld.c
==============================================================================
--- head/libexec/rtld-elf/rtld.c	Thu Feb  9 23:32:03 2017	(r313493)
+++ head/libexec/rtld-elf/rtld.c	Thu Feb  9 23:33:06 2017	(r313494)
@@ -3957,15 +3957,19 @@ symlook_default(SymLook *req, const Obj_
     donelist_init(&donelist);
     symlook_init_from_req(&req1, req);
 
-    /* Look first in the referencing object if linked symbolically. */
-    if (refobj->symbolic && !donelist_check(&donelist, refobj)) {
-	res = symlook_obj(&req1, refobj);
-	if (res == 0) {
-	    req->sym_out = req1.sym_out;
-	    req->defobj_out = req1.defobj_out;
-	    assert(req->defobj_out != NULL);
-	}
+    /*
+     * Look first in the referencing object if linked symbolically,
+     * and similarly handle protected symbols.
+     */
+    res = symlook_obj(&req1, refobj);
+    if (res == 0 && (refobj->symbolic ||
+      ELF_ST_VISIBILITY(req1.sym_out->st_other) == STV_PROTECTED)) {
+	req->sym_out = req1.sym_out;
+	req->defobj_out = req1.defobj_out;
+	assert(req->defobj_out != NULL);
     }
+    if (refobj->symbolic || req->defobj_out != NULL)
+	donelist_check(&donelist, refobj);
 
     symlook_global(req, &donelist);