From bfc731498b9ad77c23c374c6586359f4a8a49d28 Mon Sep 17 00:00:00 2001
From: 0xkato <0xkkato@gmail.com>
Date: Sun, 16 Nov 2025 00:56:07 +0100
Subject: [PATCH] fix: cap snappy/otlp decode size to 32MiB

Signed-off-by: 0xkato <0xkkato@gmail.com>
---
 storage/remote/codec.go | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/storage/remote/codec.go b/storage/remote/codec.go
index 7713f14a49..5b99c1e96f 100644
--- a/storage/remote/codec.go
+++ b/storage/remote/codec.go
@@ -64,7 +64,7 @@ func (e HTTPError) Status() int {
 
 // DecodeReadRequest reads a remote.Request from a http.Request.
 func DecodeReadRequest(r *http.Request) (*prompb.ReadRequest, error) {
-	compressed, err := io.ReadAll(io.LimitReader(r.Body, decodeReadLimit))
+	compressed, err := io.ReadAll(io.LimitReader(r.Body, int64(snappy.MaxEncodedLen(decodeReadLimit)+1)))
 	if err != nil {
 		return nil, err
 	}
@@ -921,7 +921,7 @@ func FromLabelMatchers(matchers []*prompb.LabelMatcher) ([]*labels.Matcher, erro
 // snappy decompression.
 // Used also by documentation/examples/remote_storage.
 func DecodeWriteRequest(r io.Reader) (*prompb.WriteRequest, error) {
-	compressed, err := io.ReadAll(io.LimitReader(r, decodeWriteLimit))
+	compressed, err := io.ReadAll(io.LimitReader(r, int64(snappy.MaxEncodedLen(decodeWriteLimit)+1)))
 	if err != nil {
 		return nil, err
 	}
@@ -949,7 +949,7 @@ func DecodeWriteRequest(r io.Reader) (*prompb.WriteRequest, error) {
 // snappy decompression.
 // Used also by documentation/examples/remote_storage.
 func DecodeWriteV2Request(r io.Reader) (*writev2.Request, error) {
-	compressed, err := io.ReadAll(io.LimitReader(r, decodeWriteLimit))
+	compressed, err := io.ReadAll(io.LimitReader(r, int64(snappy.MaxEncodedLen(decodeWriteLimit)+1)))
 	if err != nil {
 		return nil, err
 	}