Improved dlsym tests and fixes to linker
Answers the question: what if dependent library
was preloaded with RTLD_LOCAL flag.
Also add test for RTLD_NEXT within local_group.
Bug: http://b/17512583
Change-Id: I79e081e68b3a8c0ed8980d4275a06515fea94ec9
(cherry picked from commit 697bd9fd38ab078a117ad9a5777cf286c467b9b9)
diff --git a/linker/linker.cpp b/linker/linker.cpp
index c6decee..64b6d4d 100644
--- a/linker/linker.cpp
+++ b/linker/linker.cpp
@@ -933,13 +933,17 @@
}
-// This is used by dlsym(3). It performs symbol lookup only within the
-// specified soinfo object and its dependencies in breadth first order.
-const ElfW(Sym)* dlsym_handle_lookup(soinfo* si, soinfo** found, const char* name) {
+static const ElfW(Sym)* dlsym_handle_lookup(soinfo* root, soinfo* skip_until,
+ soinfo** found, SymbolName& symbol_name) {
const ElfW(Sym)* result = nullptr;
- SymbolName symbol_name(name);
+ bool skip_lookup = skip_until != nullptr;
- walk_dependencies_tree(&si, 1, [&](soinfo* current_soinfo) {
+ walk_dependencies_tree(&root, 1, [&](soinfo* current_soinfo) {
+ if (skip_lookup) {
+ skip_lookup = current_soinfo != skip_until;
+ return true;
+ }
+
if (!current_soinfo->find_symbol_by_name(symbol_name, nullptr, &result)) {
result = nullptr;
return false;
@@ -956,6 +960,13 @@
return result;
}
+// This is used by dlsym(3). It performs symbol lookup only within the
+// specified soinfo object and its dependencies in breadth first order.
+const ElfW(Sym)* dlsym_handle_lookup(soinfo* si, soinfo** found, const char* name) {
+ SymbolName symbol_name(name);
+ return dlsym_handle_lookup(si, nullptr, found, symbol_name);
+}
+
/* This is used by dlsym(3) to performs a global symbol lookup. If the
start value is null (for RTLD_DEFAULT), the search starts at the
beginning of the global solist. Otherwise the search starts at the
@@ -993,31 +1004,13 @@
}
}
- // If not found - look into local_group unless
- // caller is part of the global group in which
+ // If not found - use dlsym_handle_lookup for caller's
+ // local_group unless it is part of the global group in which
// case we already did it.
if (s == nullptr && caller != nullptr &&
(caller->get_rtld_flags() & RTLD_GLOBAL) == 0) {
- soinfo* local_group_root = caller->get_local_group_root();
-
- if (handle == RTLD_DEFAULT) {
- start = local_group_root;
- }
-
- for (soinfo* si = start; si != nullptr; si = si->next) {
- if (si->get_local_group_root() != local_group_root) {
- break;
- }
-
- if (!si->find_symbol_by_name(symbol_name, nullptr, &s)) {
- return nullptr;
- }
-
- if (s != nullptr) {
- *found = si;
- break;
- }
- }
+ return dlsym_handle_lookup(caller->get_local_group_root(),
+ (handle == RTLD_NEXT) ? caller : nullptr, found, symbol_name);
}
if (s != nullptr) {