From: Anders Kaseorg <andersk@MIT.EDU>
Date: Fri, 27 Sep 2013 10:23:55 +0000 (-0400)
Subject: submodule foreach: skip eval for more than one argument
X-Git-Tag: v1.9-rc0~102^2
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/1c4fb136dbad762c9c4350ee79c3474ae8037587?ds=sidebyside

submodule foreach: skip eval for more than one argument

'eval "$@"' creates an extra layer of shell interpretation, which is
probably not expected by a user who passes multiple arguments to git
submodule foreach:

$ git grep "'"
[searches for single quotes]
$ git submodule foreach git grep "'"
Entering '[submodule]'
/usr/lib/git-core/git-submodule: 1: eval: Syntax error: Unterminated quoted string
Stopping at '[submodule]'; script returned non-zero status.

To fix this, if the user passes more than one argument, execute "$@"
directly instead of passing it to eval.

Examples:

* Typical usage when adding an extra level of quoting is to pass a
single argument representing the entire command to be passed to the
shell.  This doesn't change that.

* One can imagine someone feeding untrusted input as an argument:

git submodule foreach git grep "$variable"

That currently results in a nonobvious shell code injection
vulnerability.  Executing the command named by the arguments
directly, as in this patch, fixes it.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Acked-by: Johan Herland <johan@herland.net>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
---

diff --git a/git-submodule.sh b/git-submodule.sh
index 2979197087..7b2a83d70f 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -545,7 +545,12 @@ cmd_foreach()
 				sm_path=$(relative_path "$sm_path") &&
 				# we make $path available to scripts ...
 				path=$sm_path &&
-				eval "$@" &&
+				if test $# -eq 1
+				then
+					eval "$1"
+				else
+					"$@"
+				fi &&
 				if test -n "$recursive"
 				then
 					cmd_foreach "--recursive" "$@"
diff --git a/t/t7407-submodule-foreach.sh b/t/t7407-submodule-foreach.sh
index be93f10cf0..6b2fd39aaa 100755
--- a/t/t7407-submodule-foreach.sh
+++ b/t/t7407-submodule-foreach.sh
@@ -329,4 +329,13 @@ test_expect_success 'command passed to foreach --recursive retains notion of std
 	test_cmp expected actual
 '
 
+test_expect_success 'multi-argument command passed to foreach is not shell-evaluated twice' '
+	(
+		cd super &&
+		git submodule foreach "echo \\\"quoted\\\"" > ../expected &&
+		git submodule foreach echo \"quoted\" > ../actual
+	) &&
+	test_cmp expected actual
+'
+
 test_done