fix ffmpeg snapshot template injection

This commit is contained in:
YuLi
2026-07-24 15:36:38 -07:00
parent ac64e3314b
commit 36bad5ccf2
2 changed files with 29 additions and 2 deletions

View File

@@ -461,6 +461,33 @@ void FFmpegSnap::makeSnap(bool async, const string &play_url, const string &save
GET_CONFIG(string, ffmpeg_bin, FFmpeg::kBin);
GET_CONFIG(string, ffmpeg_snap, FFmpeg::kSnap);
GET_CONFIG(string, ffmpeg_log, FFmpeg::kLog);
// The template is passed to snprintf and the resulting command is executed.
// Only accept the documented three string placeholders, with the executable
// as the first argument. This also rejects dangerous format specifiers such
// as %n and prevents a configured template from selecting another program.
size_t placeholder_count = 0;
bool valid_template = start_with(ffmpeg_snap, "%s");
for (size_t i = 0; valid_template && i < ffmpeg_snap.size(); ++i) {
if (ffmpeg_snap[i] != '%') {
continue;
}
if (++i >= ffmpeg_snap.size()) {
valid_template = false;
break;
}
if (ffmpeg_snap[i] == '%') {
continue;
}
if (ffmpeg_snap[i] != 's') {
valid_template = false;
break;
}
++placeholder_count;
}
if (!valid_template || placeholder_count != 3) {
cb(false, "invalid ffmpeg snap template: expected exactly three '%s' placeholders and no other format specifiers");
return;
}
Ticker ticker;
WorkThreadPool::Instance().getPoller()->async([timeout_sec, play_url, save_path, cb, ticker]() {
auto elapsed_ms = ticker.elapsedTime();

View File

@@ -888,8 +888,8 @@ void installWebApi() {
continue;
#endif
}
if (pr.first == FFmpeg::kBin) {
WarnL << "Configuration named " << FFmpeg::kBin << " is not allowed to be set by setServerConfig api.";
if (pr.first == FFmpeg::kBin || pr.first == FFmpeg::kSnap) {
WarnL << "Configuration named " << pr.first << " is not allowed to be set by setServerConfig api.";
continue;
}
if (ini[pr.first] == pr.second) {