Add a way to track all dlsym calls
Add dlsym option to debug.ld.all and debug.ld.app.<appname> which
enables logging of dlsym calls.
Bug: http://b/29458203
Test: flash, set debug.ld.all to dlsym and check
if there are messages in logcat
Change-Id: I9cb815a38b5b98aac9ebe3ac1540bcdedd2e8db0
diff --git a/linker/linker.cpp b/linker/linker.cpp
index d3ab8d8..fc8d1ef 100644
--- a/linker/linker.cpp
+++ b/linker/linker.cpp
@@ -1869,15 +1869,33 @@
}
#endif
- if (sym_name == nullptr) {
- DL_ERR("dlsym failed: symbol name is null");
- return false;
- }
-
soinfo* found = nullptr;
const ElfW(Sym)* sym = nullptr;
soinfo* caller = find_containing_library(caller_addr);
android_namespace_t* ns = get_caller_namespace(caller);
+ soinfo* si = nullptr;
+ if (handle != RTLD_DEFAULT && handle != RTLD_NEXT) {
+ si = soinfo_from_handle(handle);
+ }
+
+ LD_LOG(kLogDlsym,
+ "dlsym(handle=%p(\"%s\"), sym_name=\"%s\", sym_ver=\"%s\", caller=\"%s\", caller_ns=%s@%p) ...",
+ handle,
+ si != nullptr ? si->get_realpath() : "n/a",
+ sym_name,
+ sym_ver,
+ caller == nullptr ? "(null)" : caller->get_realpath(),
+ ns == nullptr ? "(null)" : ns->get_name(),
+ ns);
+
+ auto failure_guard = make_scope_guard([&]() {
+ LD_LOG(kLogDlsym, "... dlsym failed: %s", linker_get_error_buffer());
+ });
+
+ if (sym_name == nullptr) {
+ DL_ERR("dlsym failed: symbol name is null");
+ return false;
+ }
version_info vi_instance;
version_info* vi = nullptr;
@@ -1891,7 +1909,6 @@
if (handle == RTLD_DEFAULT || handle == RTLD_NEXT) {
sym = dlsym_linear_lookup(ns, sym_name, vi, &found, caller, handle);
} else {
- soinfo* si = soinfo_from_handle(handle);
if (si == nullptr) {
DL_ERR("dlsym failed: invalid handle: %p", handle);
return false;
@@ -1904,6 +1921,10 @@
if ((bind == STB_GLOBAL || bind == STB_WEAK) && sym->st_shndx != 0) {
*symbol = reinterpret_cast<void*>(found->resolve_symbol_address(sym));
+ failure_guard.disable();
+ LD_LOG(kLogDlsym,
+ "... dlsym successful: sym_name=\"%s\", sym_ver=\"%s\", found in=\"%s\", address=%p",
+ sym_name, sym_ver, found->get_soname(), *symbol);
return true;
}
diff --git a/linker/linker_logger.h b/linker/linker_logger.h
index 0932471..502f872 100644
--- a/linker/linker_logger.h
+++ b/linker/linker_logger.h
@@ -40,6 +40,7 @@
constexpr const uint32_t kLogErrors = 1 << 0;
constexpr const uint32_t kLogDlopen = 1 << 1;
+constexpr const uint32_t kLogDlsym = 1 << 2;
class LinkerLogger {
public:
