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Add more linker debug log.
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Main change is to log errors directly where they occur, to correlate with
other dlopen/dlsym logs.

Test: Build & boot with and without LinkerLogger::flags_ initialised to kLogDlopen
Change-Id: If36f52914dc97cedd95dc9375c291640c6891728
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@marstj
marstj committed Sep 5, 2019
1 parent e2c10d8 commit 9fe3826
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Showing 2 changed files with 42 additions and 24 deletions.
50 changes: 28 additions & 22 deletions linker/linker.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1325,25 +1325,26 @@ static bool load_library(android_namespace_t* ns,
const char* name = task->get_name();
const android_dlextinfo* extinfo = task->get_extinfo();

LD_LOG(kLogDlopen, "load_library(ns=%s, task=%s, flags=0x%x, realpath=%s)", ns->get_name(), name,
rtld_flags, realpath.c_str());
LD_LOG(kLogDlopen,
"load_library(ns=%s, task=%s, flags=0x%x, realpath=%s, search_linked_namespaces=%d)",
ns->get_name(), name, rtld_flags, realpath.c_str(), search_linked_namespaces);

if ((file_offset % PAGE_SIZE) != 0) {
DL_ERR("file offset for the library \"%s\" is not page-aligned: %" PRId64, name, file_offset);
DL_OPEN_ERR("file offset for the library \"%s\" is not page-aligned: %" PRId64, name, file_offset);
return false;
}
if (file_offset < 0) {
DL_ERR("file offset for the library \"%s\" is negative: %" PRId64, name, file_offset);
DL_OPEN_ERR("file offset for the library \"%s\" is negative: %" PRId64, name, file_offset);
return false;
}

struct stat file_stat;
if (TEMP_FAILURE_RETRY(fstat(task->get_fd(), &file_stat)) != 0) {
DL_ERR("unable to stat file for the library \"%s\": %s", name, strerror(errno));
DL_OPEN_ERR("unable to stat file for the library \"%s\": %s", name, strerror(errno));
return false;
}
if (file_offset >= file_stat.st_size) {
DL_ERR("file offset for the library \"%s\" >= file size: %" PRId64 " >= %" PRId64,
DL_OPEN_ERR("file offset for the library \"%s\" >= file size: %" PRId64 " >= %" PRId64,
name, file_offset, file_stat.st_size);
return false;
}
Expand All @@ -1363,13 +1364,13 @@ static bool load_library(android_namespace_t* ns,
}

if ((rtld_flags & RTLD_NOLOAD) != 0) {
DL_ERR("library \"%s\" wasn't loaded and RTLD_NOLOAD prevented it", name);
DL_OPEN_ERR("library \"%s\" wasn't loaded and RTLD_NOLOAD prevented it", name);
return false;
}

struct statfs fs_stat;
if (TEMP_FAILURE_RETRY(fstatfs(task->get_fd(), &fs_stat)) != 0) {
DL_ERR("unable to fstatfs file for the library \"%s\": %s", name, strerror(errno));
DL_OPEN_ERR("unable to fstatfs file for the library \"%s\": %s", name, strerror(errno));
return false;
}

Expand Down Expand Up @@ -1400,7 +1401,7 @@ static bool load_library(android_namespace_t* ns,
"(unknown)" :
task->get_needed_by()->get_realpath();

DL_ERR("library \"%s\" needed or dlopened by \"%s\" is not accessible for the namespace \"%s\"",
DL_OPEN_ERR("library \"%s\" needed or dlopened by \"%s\" is not accessible for the namespace \"%s\"",
name, needed_or_dlopened_by, ns->get_name());

// do not print this if a library is in the list of shared libraries for linked namespaces
Expand Down Expand Up @@ -1498,10 +1499,15 @@ static bool load_library(android_namespace_t* ns,
return load_library(ns, task, load_tasks, rtld_flags, realpath, search_linked_namespaces);
}

LD_LOG(kLogDlopen,
"load_library(ns=%s, task=%s, flags=0x%x, search_linked_namespaces=%d): calling "
"open_library with realpath=%s",
ns->get_name(), name, rtld_flags, search_linked_namespaces, realpath.c_str());

// Open the file.
int fd = open_library(ns, zip_archive_cache, name, needed_by, &file_offset, &realpath);
if (fd == -1) {
DL_ERR("library \"%s\" not found", name);
DL_OPEN_ERR("library \"%s\" not found", name);
return false;
}

Expand Down Expand Up @@ -2267,26 +2273,26 @@ void* do_dlopen(const char* name, int flags,
[&]() { LD_LOG(kLogDlopen, "... dlopen failed: %s", linker_get_error_buffer()); });

if ((flags & ~(RTLD_NOW|RTLD_LAZY|RTLD_LOCAL|RTLD_GLOBAL|RTLD_NODELETE|RTLD_NOLOAD)) != 0) {
DL_ERR("invalid flags to dlopen: %x", flags);
DL_OPEN_ERR("invalid flags to dlopen: %x", flags);
return nullptr;
}

if (extinfo != nullptr) {
if ((extinfo->flags & ~(ANDROID_DLEXT_VALID_FLAG_BITS)) != 0) {
DL_ERR("invalid extended flags to android_dlopen_ext: 0x%" PRIx64, extinfo->flags);
DL_OPEN_ERR("invalid extended flags to android_dlopen_ext: 0x%" PRIx64, extinfo->flags);
return nullptr;
}

if ((extinfo->flags & ANDROID_DLEXT_USE_LIBRARY_FD) == 0 &&
(extinfo->flags & ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET) != 0) {
DL_ERR("invalid extended flag combination (ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET without "
DL_OPEN_ERR("invalid extended flag combination (ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET without "
"ANDROID_DLEXT_USE_LIBRARY_FD): 0x%" PRIx64, extinfo->flags);
return nullptr;
}

if ((extinfo->flags & ANDROID_DLEXT_USE_NAMESPACE) != 0) {
if (extinfo->library_namespace == nullptr) {
DL_ERR("ANDROID_DLEXT_USE_NAMESPACE is set but extinfo->library_namespace is null");
DL_OPEN_ERR("ANDROID_DLEXT_USE_NAMESPACE is set but extinfo->library_namespace is null");
return nullptr;
}
ns = extinfo->library_namespace;
Expand Down Expand Up @@ -2403,7 +2409,7 @@ bool do_dlsym(void* handle,
ScopedTrace trace("dlsym");
#if !defined(__LP64__)
if (handle == nullptr) {
DL_ERR("dlsym failed: library handle is null");
DL_SYM_ERR("dlsym failed: library handle is null");
return false;
}
#endif
Expand Down Expand Up @@ -2431,7 +2437,7 @@ bool do_dlsym(void* handle,
[&]() { LD_LOG(kLogDlsym, "... dlsym failed: %s", linker_get_error_buffer()); });

if (sym_name == nullptr) {
DL_ERR("dlsym failed: symbol name is null");
DL_SYM_ERR("dlsym failed: symbol name is null");
return false;
}

Expand All @@ -2448,7 +2454,7 @@ bool do_dlsym(void* handle,
sym = dlsym_linear_lookup(ns, sym_name, vi, &found, caller, handle);
} else {
if (si == nullptr) {
DL_ERR("dlsym failed: invalid handle: %p", handle);
DL_SYM_ERR("dlsym failed: invalid handle: %p", handle);
return false;
}
sym = dlsym_handle_lookup(si, &found, sym_name, vi);
Expand All @@ -2464,8 +2470,8 @@ bool do_dlsym(void* handle,
// copy of the symbol.
const soinfo_tls* tls_module = found->get_tls();
if (tls_module == nullptr) {
DL_ERR("TLS symbol \"%s\" in solib \"%s\" with no TLS segment",
sym_name, found->get_realpath());
DL_SYM_ERR("TLS symbol \"%s\" in solib \"%s\" with no TLS segment",
sym_name, found->get_realpath());
return false;
}
void* tls_block = get_tls_block_for_this_thread(tls_module, /*should_alloc=*/true);
Expand All @@ -2480,11 +2486,11 @@ bool do_dlsym(void* handle,
return true;
}

DL_ERR("symbol \"%s\" found but not global", symbol_display_name(sym_name, sym_ver).c_str());
DL_SYM_ERR("symbol \"%s\" found but not global", symbol_display_name(sym_name, sym_ver).c_str());
return false;
}

DL_ERR("undefined symbol: %s", symbol_display_name(sym_name, sym_ver).c_str());
DL_SYM_ERR("undefined symbol: %s", symbol_display_name(sym_name, sym_ver).c_str());
return false;
}

Expand All @@ -2493,7 +2499,7 @@ int do_dlclose(void* handle) {
ProtectedDataGuard guard;
soinfo* si = soinfo_from_handle(handle);
if (si == nullptr) {
DL_ERR("invalid handle: %p", handle);
DL_OPEN_ERR("invalid handle: %p", handle);
return -1;
}

Expand Down
16 changes: 14 additions & 2 deletions linker/linker_globals.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -53,8 +53,20 @@ void DL_WARN_documented_change(int api_level, const char* doc_link, const char*

#define DL_ERR_AND_LOG(fmt, x...) \
do { \
DL_ERR(fmt, x); \
PRINT(fmt, x); \
DL_ERR(fmt, ##x); \
PRINT(fmt, ##x); \
} while (false)

#define DL_OPEN_ERR(fmt, x...) \
do { \
DL_ERR(fmt, ##x); \
LD_LOG(kLogDlopen, fmt, ##x); \
} while (false)

#define DL_SYM_ERR(fmt, x...) \
do { \
DL_ERR(fmt, ##x); \
LD_LOG(kLogDlsym, fmt, ##x); \
} while (false)

constexpr ElfW(Versym) kVersymNotNeeded = 0;
Expand Down

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