The Go programming language
Go to file
Damien Neil 3991f6c41c [release-branch.go1.20] net/textproto: avoid overpredicting the number of MIME header keys
A parsed MIME header is a map[string][]string. In the common case,
a header contains many one-element []string slices. To avoid
allocating a separate slice for each key, ReadMIMEHeader looks
ahead in the input to predict the number of keys that will be
parsed, and allocates a single []string of that length.
The individual slices are then allocated out of the larger one.

The prediction of the number of header keys was done by counting
newlines in the input buffer, which does not take into account
header continuation lines (where a header key/value spans multiple
lines) or the end of the header block and the start of the body.
This could lead to a substantial amount of overallocation, for
example when the body consists of nothing but a large block of
newlines.

Fix header key count prediction to take into account the end of
the headers (indicated by a blank line) and continuation lines
(starting with whitespace).

Thanks to Jakob Ackermann (@das7pad) for reporting this issue.

Fixes CVE-2023-24534
For #58975
Fixes #59268

Change-Id: I0591593e67b6fdba22a32dcc3334fad797727f5c
Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/1802452
Run-TryBot: Damien Neil <dneil@google.com>
Reviewed-by: Roland Shoemaker <bracewell@google.com>
Reviewed-by: Julie Qiu <julieqiu@google.com>
Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/1802397
Run-TryBot: Roland Shoemaker <bracewell@google.com>
TryBot-Result: Security TryBots <security-trybots@go-security-trybots.iam.gserviceaccount.com>
Reviewed-on: https://go-review.googlesource.com/c/go/+/481988
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Bypass: Michael Knyszek <mknyszek@google.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2023-04-04 16:58:09 +00:00
.github .github: suggest using private browsing in pkgsite template 2023-01-03 18:52:47 +00:00
api api: promote next to go1.20 2022-12-07 16:56:12 +00:00
doc [release-branch.go1.20] time: revert strict parsing of RFC 3339 2023-01-18 20:42:20 +00:00
lib/time lib/time: update to 2022g/2022g 2022-12-07 00:25:27 +00:00
misc [release-branch.go1.20] cmd/compile: re-compile instantiated generic methods in linkshared mode 2023-03-29 18:40:30 +00:00
src [release-branch.go1.20] net/textproto: avoid overpredicting the number of MIME header keys 2023-04-04 16:58:09 +00:00
test [release-branch.go1.20] cmd/compile: don't assume pointer of a slice is non-nil 2023-03-29 19:07:23 +00:00
.gitattributes all: treat all files as binary, but check in .bat with CRLF 2020-06-08 15:31:43 +00:00
.gitignore internal/buildcfg: move build configuration out of cmd/internal/objabi 2021-04-16 19:20:53 +00:00
CONTRIBUTING.md all: restore changes from faulty merge/revert 2018-02-12 20:13:59 +00:00
LICENSE doc: revert copyright date to 2009 2016-06-01 22:40:04 +00:00
PATENTS
README.md README: update from CC-BY-3.0 to CC-BY-4.0 2022-11-02 20:14:56 +00:00
SECURITY.md SECURITY.md: replace golang.org with go.dev 2022-04-26 19:59:47 +00:00
VERSION [release-branch.go1.20] go1.20.2 2023-03-07 16:47:18 +00:00
codereview.cfg [release-branch.go1.20] update codereview.cfg for release-branch.go1.20 2022-12-07 18:00:33 +00:00

README.md

The Go Programming Language

Go is an open source programming language that makes it easy to build simple, reliable, and efficient software.

Gopher image Gopher image by Renee French, licensed under Creative Commons 4.0 Attributions license.

Our canonical Git repository is located at https://go.googlesource.com/go. There is a mirror of the repository at https://github.com/golang/go.

Unless otherwise noted, the Go source files are distributed under the BSD-style license found in the LICENSE file.

Download and Install

Binary Distributions

Official binary distributions are available at https://go.dev/dl/.

After downloading a binary release, visit https://go.dev/doc/install for installation instructions.

Install From Source

If a binary distribution is not available for your combination of operating system and architecture, visit https://go.dev/doc/install/source for source installation instructions.

Contributing

Go is the work of thousands of contributors. We appreciate your help!

To contribute, please read the contribution guidelines at https://go.dev/doc/contribute.

Note that the Go project uses the issue tracker for bug reports and proposals only. See https://go.dev/wiki/Questions for a list of places to ask questions about the Go language.