Sync with Git 2.30.2 for CVE-2021-21300

Signed-off-by: Junio C Hamano <gitster@pobox.com>

3 files changed, 144 insertions, 3 deletions

diff --git a/t/t0021-conversion.sh b/t/t0021-conversion.sh
index e828ee964c..a9e10a0c21 100755
--- a/t/t0021-conversion.sh
+++ b/t/t0021-conversion.sh
@@ -956,4 +956,85 @@ test_expect_success PERL 'invalid file in delayed checkout' '
 	grep "error: external filter .* signaled that .unfiltered. is now available although it has not been delayed earlier" git-stderr.log
 '
 
+for mode in 'case' 'utf-8'
+do
+	case "$mode" in
+	case)	dir='A' symlink='a' mode_prereq='CASE_INSENSITIVE_FS' ;;
+	utf-8)
+		dir=$(printf "\141\314\210") symlink=$(printf "\303\244")
+		mode_prereq='UTF8_NFD_TO_NFC' ;;
+	esac
+
+	test_expect_success PERL,SYMLINKS,$mode_prereq \
+	"delayed checkout with $mode-collision don't write to the wrong place" '
+		test_config_global filter.delay.process \
+			"\"$TEST_ROOT/rot13-filter.pl\" --always-delay delayed.log clean smudge delay" &&
+		test_config_global filter.delay.required true &&
+
+		git init $mode-collision &&
+		(
+			cd $mode-collision &&
+			mkdir target-dir &&
+
+			empty_oid=$(printf "" | git hash-object -w --stdin) &&
+			symlink_oid=$(printf "%s" "$PWD/target-dir" | git hash-object -w --stdin) &&
+			attr_oid=$(echo "$dir/z filter=delay" | git hash-object -w --stdin) &&
+
+			cat >objs <<-EOF &&
+			100644 blob $empty_oid	$dir/x
+			100644 blob $empty_oid	$dir/y
+			100644 blob $empty_oid	$dir/z
+			120000 blob $symlink_oid	$symlink
+			100644 blob $attr_oid	.gitattributes
+			EOF
+
+			git update-index --index-info <objs &&
+			git commit -m "test commit"
+		) &&
+
+		git clone $mode-collision $mode-collision-cloned &&
+		# Make sure z was really delayed
+		grep "IN: smudge $dir/z .* \\[DELAYED\\]" $mode-collision-cloned/delayed.log &&
+
+		# Should not create $dir/z at $symlink/z
+		test_path_is_missing $mode-collision/target-dir/z
+	'
+done
+
+test_expect_success PERL,SYMLINKS,CASE_INSENSITIVE_FS \
+"delayed checkout with submodule collision don't write to the wrong place" '
+	git init collision-with-submodule &&
+	(
+		cd collision-with-submodule &&
+		git config filter.delay.process "\"$TEST_ROOT/rot13-filter.pl\" --always-delay delayed.log clean smudge delay" &&
+		git config filter.delay.required true &&
+
+		# We need Git to treat the submodule "a" and the
+		# leading dir "A" as different paths in the index.
+		git config --local core.ignoreCase false &&
+
+		empty_oid=$(printf "" | git hash-object -w --stdin) &&
+		attr_oid=$(echo "A/B/y filter=delay" | git hash-object -w --stdin) &&
+		cat >objs <<-EOF &&
+		100644 blob $empty_oid	A/B/x
+		100644 blob $empty_oid	A/B/y
+		100644 blob $attr_oid	.gitattributes
+		EOF
+		git update-index --index-info <objs &&
+
+		git init a &&
+		mkdir target-dir &&
+		symlink_oid=$(printf "%s" "$PWD/target-dir" | git -C a hash-object -w --stdin) &&
+		echo "120000 blob $symlink_oid	b" >objs &&
+		git -C a update-index --index-info <objs &&
+		git -C a commit -m sub &&
+		git submodule add ./a &&
+		git commit -m super &&
+
+		git checkout --recurse-submodules . &&
+		grep "IN: smudge A/B/y .* \\[DELAYED\\]" delayed.log &&
+		test_path_is_missing target-dir/y
+	)
+'
+
 test_done
diff --git a/t/t0021/rot13-filter.pl b/t/t0021/rot13-filter.pl
index cd32a82da5..7bb93768f3 100644
--- a/t/t0021/rot13-filter.pl
+++ b/t/t0021/rot13-filter.pl
@@ -2,9 +2,15 @@
 # Example implementation for the Git filter protocol version 2
 # See Documentation/gitattributes.txt, section "Filter Protocol"
 #
-# The first argument defines a debug log file that the script write to.
-# All remaining arguments define a list of supported protocol
-# capabilities ("clean", "smudge", etc).
+# Usage: rot13-filter.pl [--always-delay] <log path> <capabilities>
+#
+# Log path defines a debug log file that the script writes to. The
+# subsequent arguments define a list of supported protocol capabilities
+# ("clean", "smudge", etc).
+#
+# When --always-delay is given all pathnames with the "can-delay" flag
+# that don't appear on the list bellow are delayed with a count of 1
+# (see more below).
 #
 # This implementation supports special test cases:
 # (1) If data with the pathname "clean-write-fail.r" is processed with
@@ -53,6 +59,13 @@ use IO::File;
 use Git::Packet;
 
 my $MAX_PACKET_CONTENT_SIZE = 65516;
+
+my $always_delay = 0;
+if ( $ARGV[0] eq '--always-delay' ) {
+	$always_delay = 1;
+	shift @ARGV;
+}
+
 my $log_file                = shift @ARGV;
 my @capabilities            = @ARGV;
 
@@ -134,6 +147,8 @@ while (1) {
 			if ( $buffer eq "can-delay=1" ) {
 				if ( exists $DELAY{$pathname} and $DELAY{$pathname}{"requested"} == 0 ) {
 					$DELAY{$pathname}{"requested"} = 1;
+				} elsif ( !exists $DELAY{$pathname} and $always_delay ) {
+					$DELAY{$pathname} = { "requested" => 1, "count" => 1 };
 				}
 			} elsif ($buffer =~ /^(ref|treeish|blob)=/) {
 				print $debug " $buffer";
diff --git a/t/t2006-checkout-index-basic.sh b/t/t2006-checkout-index-basic.sh
index 7ff3edab05..7705e3a317 100755
--- a/t/t2006-checkout-index-basic.sh
+++ b/t/t2006-checkout-index-basic.sh
@@ -31,6 +31,51 @@ test_expect_success 'checkout-index reports errors (stdin)' '
 	test_must_fail git checkout-index --stdin 2>stderr &&
 	test_i18ngrep not.in.the.cache stderr
 '
+for mode in 'case' 'utf-8'
+do
+	case "$mode" in
+	case)	dir='A' symlink='a' mode_prereq='CASE_INSENSITIVE_FS' ;;
+	utf-8)
+		dir=$(printf "\141\314\210") symlink=$(printf "\303\244")
+		mode_prereq='UTF8_NFD_TO_NFC' ;;
+	esac
+
+	test_expect_success SYMLINKS,$mode_prereq \
+	"checkout-index with $mode-collision don't write to the wrong place" '
+		git init $mode-collision &&
+		(
+			cd $mode-collision &&
+			mkdir target-dir &&
+
+			empty_obj_hex=$(git hash-object -w --stdin </dev/null) &&
+			symlink_hex=$(printf "%s" "$PWD/target-dir" | git hash-object -w --stdin) &&
+
+			cat >objs <<-EOF &&
+			100644 blob ${empty_obj_hex}	${dir}/x
+			100644 blob ${empty_obj_hex}	${dir}/y
+			100644 blob ${empty_obj_hex}	${dir}/z
+			120000 blob ${symlink_hex}	${symlink}
+			EOF
+
+			git update-index --index-info <objs &&
+
+			# Note: the order is important here to exercise the
+			# case where the file at ${dir} has its type changed by
+			# the time Git tries to check out ${dir}/z.
+			#
+			# Also, we use core.precomposeUnicode=false because we
+			# want Git to treat the UTF-8 paths transparently on
+			# Mac OS, matching what is in the index.
+			#
+			git -c core.precomposeUnicode=false checkout-index -f \
+				${dir}/x ${dir}/y ${symlink} ${dir}/z &&
+
+			# Should not create ${dir}/z at ${symlink}/z
+			test_path_is_missing target-dir/z
+
+		)
+	'
+done
 
 test_expect_success 'checkout-index --temp correctly reports error on missing blobs' '
 	test_when_finished git reset --hard &&