File CVE-2024-21647.patch of Package rubygem-puma.35973
From bbb880ffb6debbfdea535b4b3eb2204d49ae151d Mon Sep 17 00:00:00 2001
From: Nate Berkopec <nate.berkopec@gmail.com>
Date: Mon, 8 Jan 2024 14:48:43 +0900
Subject: [PATCH] Merge pull request from GHSA-c2f4-cvqm-65w2
Co-authored-by: MSP-Greg <MSP-Greg@users.noreply.github.com>
Co-authored-by: Patrik Ragnarsson <patrik@starkast.net>
Co-authored-by: Evan Phoenix <evan@phx.io>
diff --git a/lib/puma/client.rb b/lib/puma/client.rb
index cd89e8fe..796c25b3 100644
--- a/lib/puma/client.rb
+++ b/lib/puma/client.rb
@@ -48,6 +48,14 @@ module Puma
CHUNK_VALID_ENDING = Const::LINE_END
CHUNK_VALID_ENDING_SIZE = CHUNK_VALID_ENDING.bytesize
+ # The maximum number of bytes we'll buffer looking for a valid
+ # chunk header.
+ MAX_CHUNK_HEADER_SIZE = 4096
+
+ # The maximum amount of excess data the client sends
+ # using chunk size extensions before we abort the connection.
+ MAX_CHUNK_EXCESS = 16 * 1024
+
# Content-Length header value validation
CONTENT_LENGTH_VALUE_INVALID = /[^\d]/.freeze
@@ -441,6 +449,7 @@ module Puma
@chunked_body = true
@partial_part_left = 0
@prev_chunk = ""
+ @excess_cr = 0
@body = Tempfile.new(Const::PUMA_TMP_BASE)
@body.binmode
@@ -513,6 +522,20 @@ module Puma
end
end
+ # Track the excess as a function of the size of the
+ # header vs the size of the actual data. Excess can
+ # go negative (and is expected to) when the body is
+ # significant.
+ # The additional of chunk_hex.size and 2 compensates
+ # for a client sending 1 byte in a chunked body over
+ # a long period of time, making sure that that client
+ # isn't accidentally eventually punished.
+ @excess_cr += (line.size - len - chunk_hex.size - 2)
+
+ if @excess_cr >= MAX_CHUNK_EXCESS
+ raise HttpParserError, "Maximum chunk excess detected"
+ end
+
len += 2
part = io.read(len)
@@ -540,6 +563,10 @@ module Puma
@partial_part_left = len - part.size
end
else
+ if @prev_chunk.size + chunk.size >= MAX_CHUNK_HEADER_SIZE
+ raise HttpParserError, "maximum size of chunk header exceeded"
+ end
+
@prev_chunk = line
return false
end