Skip to content

http: create header field names as internalized strings #64277

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
araujogui wants to merge 2 commits into
base: main
Choose a base branch
from
+19 −2
Open

http: create header field names as internalized strings #64277

Changes from 1 commit
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
f1a205d
http: create header field names as internalized strings
araujogui Jul 4, 2026
fff2fbc
http: only internalize short header field names
araujogui Jul 4, 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
15 changes: 14 additions & 1 deletion src/node_http_parser.cc
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -65,6 +65,7 @@ using v8::Isolate;
using v8::Local;
using v8::LocalVector;
using v8::MaybeLocal;
using v8::NewStringType;
using v8::Number;
using v8::Object;
using v8::ObjectTemplate;
Expand Down Expand Up @@ -233,6 +234,17 @@ struct StringPtr {
return String::Empty(env->isolate());
}

Local<String> ToInternalizedString(Environment* env) const {
if (size_ != 0) {
return String::NewFromOneByte(env->isolate(),
reinterpret_cast<const uint8_t*>(str_),
NewStringType::kInternalized,
size_)

@jasnell jasnell Jul 8, 2026

Copy link
Copy Markdown
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

hmm.. I'm not convinced this is a good idea.

While it certainly helps legitimate cases, there's a risk here.

A malicious sender could leverage this into a memory leak or cause significant additional GC pressure pretty easily by sending a large number of intentionally different header values at a high rate. Internalized strings do get cleaned up during a major GC. The current existing non-internalized strings can be cleaned up in a minor GC.

We really ought to be internalizing only known header names.

@araujogui araujogui Jul 8, 2026

Copy link
Copy Markdown
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

You're right, should I apply the same fix on the HTTP/2 path?

node/src/node_http_common-inl.h

Line 126 in 8e1ab55

name_.reset(name, true); // Internalizable

.ToLocalChecked();
}
return String::Empty(env->isolate());
}
Comment thread
araujogui marked this conversation as resolved.

// Strip trailing OWS (SPC or HTAB) from string.
Local<String> ToTrimmedString(Environment* env) {
while (size_ > 0 && IsOWS(str_[size_ - 1])) {
Expand Down Expand Up @@ -940,7 +952,8 @@ class Parser : public AsyncWrap, public StreamListener {
Local<Value> headers_v[kMaxHeaderFieldsCount * 2];

for (size_t i = 0; i < num_values_; ++i) {
headers_v[i * 2] = fields_[i].ToString(env());
// Field names repeat across requests, so internalize them.
headers_v[i * 2] = fields_[i].ToInternalizedString(env());
headers_v[i * 2 + 1] = values_[i].ToTrimmedString(env());
}

Expand Down
Loading