Skip to content

Fix race condition in FontFile data access during threaded imports #107224

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
d6e wants to merge 3 commits into
base: master
Choose a base branch
from
+22 −6
Open

Fix race condition in FontFile data access during threaded imports #107224

Show file tree
Hide file tree
Changes from 2 commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
7c26d93
Fix thread safety issue in resource changed callbacks during imports
Jun 6, 2025
adba698
Fix race condition in FontFile data access during threaded imports
Jan 12, 2026
3542546
Remove include from scene/resources/font.h
d6e Jan 14, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion core/io/resource_loader.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -968,7 +968,7 @@ void ResourceLoader::resource_changed_emit(Resource *p_source) {

for (const ThreadLoadTask::ResourceChangedConnection &rcc : curr_load_task->resource_changed_connections) {
if (unlikely(rcc.source == p_source)) {
rcc.callable.call();
rcc.callable.call_deferred();
}
}
}
Expand Down
24 changes: 19 additions & 5 deletions scene/resources/font.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -591,6 +591,8 @@ _FORCE_INLINE_ void FontFile::_ensure_rid(int p_cache_index, int p_make_linked_f
if (p_make_linked_from >= 0 && p_make_linked_from != p_cache_index && p_make_linked_from < cache.size()) {
cache.write[p_cache_index] = TS->create_font_linked_variation(cache[p_make_linked_from]);
} else {
MutexLock lock(data_mutex);

cache.write[p_cache_index] = TS->create_font();
TS->font_set_data_ptr(cache[p_cache_index], data_ptr, data_size);
TS->font_set_antialiasing(cache[p_cache_index], antialiasing);
Expand Down Expand Up @@ -1408,9 +1410,13 @@ void FontFile::_get_property_list(List<PropertyInfo> *p_list) const {

void FontFile::reset_state() {
_clear_cache();
data.clear();
data_ptr = nullptr;
data_size = 0;
{
MutexLock lock(data_mutex);
data = PackedByteArray();
data_ptr = nullptr;
data_size = 0;
data_external = false;
}
cache.clear();

antialiasing = TextServer::FONT_ANTIALIASING_GRAY;
Expand Down Expand Up @@ -2070,9 +2076,12 @@ Error FontFile::load_dynamic_font(const String &p_path) {
}

void FontFile::set_data_ptr(const uint8_t *p_data, size_t p_size) {
data.clear();
MutexLock lock(data_mutex);

data = PackedByteArray();
data_ptr = p_data;
data_size = p_size;
data_external = true;

for (int i = 0; i < cache.size(); i++) {
if (cache[i].is_valid()) {
Expand All @@ -2082,9 +2091,12 @@ void FontFile::set_data_ptr(const uint8_t *p_data, size_t p_size) {
}

void FontFile::set_data(const PackedByteArray &p_data) {
MutexLock lock(data_mutex);

data = p_data;
data_ptr = data.ptr();
data_size = data.size();
data_external = false;

for (int i = 0; i < cache.size(); i++) {
if (cache[i].is_valid()) {
Expand All @@ -2094,7 +2106,9 @@ void FontFile::set_data(const PackedByteArray &p_data) {
}

PackedByteArray FontFile::get_data() const {
if (unlikely((size_t)data.size() != data_size)) {
MutexLock lock(data_mutex);

if (unlikely(data_external && data.is_empty() && data_ptr && data_size > 0)) {
data.resize(data_size);
memcpy(data.ptrw(), data_ptr, data_size);
}
Expand Down
3 changes: 3 additions & 0 deletions scene/resources/font.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -31,6 +31,7 @@
#pragma once

#include "core/io/resource.h"
#include "core/os/mutex.h"
Comment thread
d6e marked this conversation as resolved.
Outdated
#include "core/templates/lru.h"
#include "scene/resources/texture.h"
#include "servers/text_server.h"
Expand Down Expand Up @@ -185,8 +186,10 @@ class FontFile : public Font {
RES_BASE_EXTENSION("fontdata");

// Font source data.
mutable Mutex data_mutex;
const uint8_t *data_ptr = nullptr;
size_t data_size = 0;
bool data_external = false;
mutable PackedByteArray data;

TextServer::FontAntialiasing antialiasing = TextServer::FONT_ANTIALIASING_GRAY;
Expand Down