From b4fa5b163df118b35a836bbe5706ac268b4cc14b Mon Sep 17 00:00:00 2001
From: Jes Cok <xigua67damn@gmail.com>
Date: Wed, 29 Nov 2023 16:23:18 +0000
Subject: [PATCH] debug/elf: return error in DynValue for invalid dynamic
 section size

This is a follow-up to CL 536400.

Fixes #64446

Change-Id: I35646732f62cb1937fd448f94ea518544d4295d4
GitHub-Last-Rev: 55db18a909fd44e6b2f2b98fd1a44ad01bb37932
GitHub-Pull-Request: golang/go#64448
Reviewed-on: https://go-review.googlesource.com/c/go/+/545835
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Run-TryBot: Jes Cok <xigua67damn@gmail.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
---
 src/debug/elf/file.go | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/debug/elf/file.go b/src/debug/elf/file.go
index fcbe76b195..7228447c21 100644
--- a/src/debug/elf/file.go
+++ b/src/debug/elf/file.go
@@ -1656,6 +1656,14 @@ func (f *File) DynValue(tag DynTag) ([]uint64, error) {
 		return nil, err
 	}
 
+	dynSize := 8
+	if f.Class == ELFCLASS64 {
+		dynSize = 16
+	}
+	if len(d)%dynSize != 0 {
+		return nil, errors.New("length of dynamic section is not a multiple of dynamic entry size")
+	}
+
 	// Parse the .dynamic section as a string of bytes.
 	var vals []uint64
 	for len(d) > 0 {
-- 
2.50.0