From 9bf748b6c4c9a17d3aa77f6b9abcfae65451febf Mon Sep 17 00:00:00 2001
From: Joe Chen <jc@unknwon.io>
Date: Tue, 7 Jun 2022 21:11:36 +0800
Subject: [PATCH] http: clean request path from Git endpoints (#7022)

---
 CHANGELOG.md                       |  1 +
 internal/pathutil/pathutil_test.go |  4 ++++
 internal/route/repo/http.go        | 17 ++++++++++++-----
 3 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 765d69351d..cb3e5cfe3e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -26,6 +26,7 @@ All notable changes to Gogs are documented in this file.
 - _Security:_ OS Command Injection in file editor. [#7000](https://github.com/gogs/gogs/issues/7000)
 - _Security:_ Sanitize `DisplayName` in repository issue list. [#7009](https://github.com/gogs/gogs/pull/7009)
 - _Security:_ Path Traversal in file editor on Windows. [#7001](https://github.com/gogs/gogs/issues/7001)
+- _Security:_ Path Traversal in Git HTTP endpoints. [#7002](https://github.com/gogs/gogs/issues/7002)
 - Unable to use LDAP authentication on ARM machines. [#6761](https://github.com/gogs/gogs/issues/6761)
 - Unable to init repository during creation on Windows. [#6967](https://github.com/gogs/gogs/issues/6967)
 - Mysterious panic on `Value not found for type *repo.HTTPContext`. [#6963](https://github.com/gogs/gogs/issues/6963)
diff --git a/internal/pathutil/pathutil_test.go b/internal/pathutil/pathutil_test.go
index d20e537a4f..7444c82a1f 100644
--- a/internal/pathutil/pathutil_test.go
+++ b/internal/pathutil/pathutil_test.go
@@ -27,6 +27,10 @@ func TestClean(t *testing.T) {
 			path:    "/../a/b/../c/../readme.txt",
 			wantVal: "a/readme.txt",
 		},
+		{
+			path:    "../../objects/info/..",
+			wantVal: "objects",
+		},
 		{
 			path:    "/a/readme.txt",
 			wantVal: "a/readme.txt",
diff --git a/internal/route/repo/http.go b/internal/route/repo/http.go
index 575719f1f7..668c4cfa98 100644
--- a/internal/route/repo/http.go
+++ b/internal/route/repo/http.go
@@ -24,6 +24,7 @@ import (
 	"gogs.io/gogs/internal/conf"
 	"gogs.io/gogs/internal/db"
 	"gogs.io/gogs/internal/lazyregexp"
+	"gogs.io/gogs/internal/pathutil"
 	"gogs.io/gogs/internal/tool"
 )
 
@@ -408,15 +409,21 @@ func HTTP(c *HTTPContext) {
 		}
 
 		if route.method != c.Req.Method {
-			c.NotFound()
+			c.Error(http.StatusNotFound)
 			return
 		}
 
-		file := strings.TrimPrefix(reqPath, m[1]+"/")
-		dir, err := getGitRepoPath(m[1])
+		cleaned := pathutil.Clean(m[1])
+		if m[1] != "/"+cleaned {
+			c.Error(http.StatusBadRequest, "Request path contains suspicious characters")
+			return
+		}
+
+		file := strings.TrimPrefix(reqPath, cleaned)
+		dir, err := getGitRepoPath(cleaned)
 		if err != nil {
 			log.Warn("HTTP.getGitRepoPath: %v", err)
-			c.NotFound()
+			c.Error(http.StatusNotFound)
 			return
 		}
 
@@ -435,5 +442,5 @@ func HTTP(c *HTTPContext) {
 		return
 	}
 
-	c.NotFound()
+	c.Error(http.StatusNotFound)
 }