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parcel-bundler
Linux: crash with `std::bad_alloc` in this case
(steps found by @deepak1556 in https://github.com/microsoft/vscode/issues/160904#issuecomment-1253196500, copying over here)
As for the crash, it is triggered in the following function https://github.com/parcel-bundler/watcher/blob/478a1ad66d44663cb24f3f73428ff2b52a244098/src/linux/InotifyBackend.cc#L149 on L152
149 bool InotifyBackend::handleSubscription(struct inotify_event *event, std::shared_ptr<InotifySubscription> sub) {
150 // Build full path and check if its in our ignore list.
151 Watcher *watcher = sub->watcher;
152 std::string path = std::string(sub->entry->path);
153 if (event->len > 0) {
154 path += "/" + std::string(event->name);
155 }
Basically sub->entry is pointing to invalid memory causing an allocation failure for std::string. But the root issue is the corrupted value of sub->entry. Following is a minimal repro,
// Following contents are from file test.js created under the root of parcel-bundler/watcher
// Make changes to the require call depending on were you place the file
const watcher = require('./');
async function start() {
const subscription = await watcher.subscribe('<path>/test-dir', () => {}, { backend: 'inotify' });
}
start()
// In terminal
* Create <path>/test-dir with a large directory, for my testing I copied `vscode/build` folder into this path
* git init // we need a certain git action to trigger this crash
* node test.js // start the test file
// In a different terminal
* cd <path>/test-dir
* mv build build1
* git checkout -q -- build
* rm -rf build1
* mv build build2
* git checkout -q -- build
* rm -rf build2 // CRASH
sub-entry points to an entry from DirTree which is held by sub->tree, the crash would be from the fact that watcher is deleting entries from the tree without invalidating sub->entry which then would be pointing to invalid memory regions and this is somehow getting used for subsequent notifications. Possible location https://github.com/parcel-bundler/watcher/blob/478a1ad66d44663cb24f3f73428ff2b52a244098/src/linux/InotifyBackend.cc#L175 and https://github.com/parcel-bundler/watcher/blob/478a1ad66d44663cb24f3f73428ff2b52a244098/src/linux/InotifyBackend.cc#L203.
I believe https://github.com/parcel-bundler/watcher/pull/103 might fix this? @DeMoorJasper @devongovett
