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Message-ID: <168141324822.157208.14911977368369619191.stgit@manet.1015granger.net>
Date: Thu, 13 Apr 2023 15:14:08 -0400
From: Chuck Lever <cel@...nel.org>
To: kuba@...nel.org, pabeni@...hat.com, edumazet@...gle.com
Cc: netdev@...r.kernel.org, kernel-tls-handshake@...ts.linux.dev
Subject: [PATCH v9 3/3] net/handshake: Add Kunit tests for the handshake
consumer API
From: Chuck Lever <chuck.lever@...cle.com>
These verify the API contracts and help exercise lifetime rules for
consumer sockets and handshake_req structures.
One way to run these tests:
./tools/testing/kunit/kunit.py run --kunitconfig ./net/handshake/.kunitconfig
Signed-off-by: Chuck Lever <chuck.lever@...cle.com>
---
net/Kconfig | 15 +
net/handshake/.kunitconfig | 11 +
net/handshake/Makefile | 2
net/handshake/handshake-test.c | 523 ++++++++++++++++++++++++++++++++++++++++
net/handshake/netlink.c | 22 ++
net/handshake/request.c | 5
6 files changed, 578 insertions(+)
create mode 100644 net/handshake/.kunitconfig
create mode 100644 net/handshake/handshake-test.c
diff --git a/net/Kconfig b/net/Kconfig
index 4b800706cc76..7d39c1773eb4 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -73,6 +73,21 @@ config NET_HANDSHAKE
depends on SUNRPC || NVME_TARGET_TCP || NVME_TCP
default y
+config NET_HANDSHAKE_KUNIT_TEST
+ tristate "KUnit tests for the handshake upcall mechanism" if !KUNIT_ALL_TESTS
+ default KUNIT_ALL_TESTS
+ depends on KUNIT
+ help
+ This builds the KUnit tests for the handshake upcall mechanism.
+
+ KUnit tests run during boot and output the results to the debug
+ log in TAP format (https://testanything.org/). Only useful for
+ kernel devs running KUnit test harness and are not for inclusion
+ into a production build.
+
+ For more information on KUnit and unit tests in general, refer
+ to the KUnit documentation in Documentation/dev-tools/kunit/.
+
config INET
bool "TCP/IP networking"
help
diff --git a/net/handshake/.kunitconfig b/net/handshake/.kunitconfig
new file mode 100644
index 000000000000..5c48cf4abca2
--- /dev/null
+++ b/net/handshake/.kunitconfig
@@ -0,0 +1,11 @@
+CONFIG_KUNIT=y
+CONFIG_UBSAN=y
+CONFIG_STACKTRACE=y
+CONFIG_NET=y
+CONFIG_NETWORK_FILESYSTEMS=y
+CONFIG_INET=y
+CONFIG_MULTIUSER=y
+CONFIG_NFS_FS=y
+CONFIG_SUNRPC=y
+CONFIG_NET_HANDSHAKE=y
+CONFIG_NET_HANDSHAKE_KUNIT_TEST=y
diff --git a/net/handshake/Makefile b/net/handshake/Makefile
index a089f7e3df24..247d73c6ff6e 100644
--- a/net/handshake/Makefile
+++ b/net/handshake/Makefile
@@ -9,3 +9,5 @@
obj-y += handshake.o
handshake-y := genl.o netlink.o request.o tlshd.o trace.o
+
+obj-$(CONFIG_NET_HANDSHAKE_KUNIT_TEST) += handshake-test.o
diff --git a/net/handshake/handshake-test.c b/net/handshake/handshake-test.c
new file mode 100644
index 000000000000..e6adc5dec11a
--- /dev/null
+++ b/net/handshake/handshake-test.c
@@ -0,0 +1,523 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2023 Oracle and/or its affiliates.
+ *
+ * KUnit test of the handshake upcall mechanism.
+ */
+
+#include <kunit/test.h>
+#include <kunit/visibility.h>
+
+#include <linux/kernel.h>
+
+#include <net/sock.h>
+#include <net/genetlink.h>
+#include <net/netns/generic.h>
+
+#include <uapi/linux/handshake.h>
+#include "handshake.h"
+
+MODULE_IMPORT_NS(EXPORTED_FOR_KUNIT_TESTING);
+
+static int test_accept_func(struct handshake_req *req, struct genl_info *info,
+ int fd)
+{
+ return 0;
+}
+
+static void test_done_func(struct handshake_req *req, unsigned int status,
+ struct genl_info *info)
+{
+}
+
+struct handshake_req_alloc_test_param {
+ const char *desc;
+ struct handshake_proto *proto;
+ gfp_t gfp;
+ bool expect_success;
+};
+
+static struct handshake_proto handshake_req_alloc_proto_2 = {
+ .hp_handler_class = HANDSHAKE_HANDLER_CLASS_NONE,
+};
+
+static struct handshake_proto handshake_req_alloc_proto_3 = {
+ .hp_handler_class = HANDSHAKE_HANDLER_CLASS_MAX,
+};
+
+static struct handshake_proto handshake_req_alloc_proto_4 = {
+ .hp_handler_class = HANDSHAKE_HANDLER_CLASS_TLSHD,
+};
+
+static struct handshake_proto handshake_req_alloc_proto_5 = {
+ .hp_handler_class = HANDSHAKE_HANDLER_CLASS_TLSHD,
+ .hp_accept = test_accept_func,
+};
+
+static struct handshake_proto handshake_req_alloc_proto_6 = {
+ .hp_handler_class = HANDSHAKE_HANDLER_CLASS_TLSHD,
+ .hp_privsize = UINT_MAX,
+ .hp_accept = test_accept_func,
+ .hp_done = test_done_func,
+};
+
+static struct handshake_proto handshake_req_alloc_proto_good = {
+ .hp_handler_class = HANDSHAKE_HANDLER_CLASS_TLSHD,
+ .hp_accept = test_accept_func,
+ .hp_done = test_done_func,
+};
+
+static const
+struct handshake_req_alloc_test_param handshake_req_alloc_params[] = {
+ {
+ .desc = "handshake_req_alloc NULL proto",
+ .proto = NULL,
+ .gfp = GFP_KERNEL,
+ .expect_success = false,
+ },
+ {
+ .desc = "handshake_req_alloc CLASS_NONE",
+ .proto = &handshake_req_alloc_proto_2,
+ .gfp = GFP_KERNEL,
+ .expect_success = false,
+ },
+ {
+ .desc = "handshake_req_alloc CLASS_MAX",
+ .proto = &handshake_req_alloc_proto_3,
+ .gfp = GFP_KERNEL,
+ .expect_success = false,
+ },
+ {
+ .desc = "handshake_req_alloc no callbacks",
+ .proto = &handshake_req_alloc_proto_4,
+ .gfp = GFP_KERNEL,
+ .expect_success = false,
+ },
+ {
+ .desc = "handshake_req_alloc no done callback",
+ .proto = &handshake_req_alloc_proto_5,
+ .gfp = GFP_KERNEL,
+ .expect_success = false,
+ },
+ {
+ .desc = "handshake_req_alloc excessive privsize",
+ .proto = &handshake_req_alloc_proto_6,
+ .gfp = GFP_KERNEL,
+ .expect_success = false,
+ },
+ {
+ .desc = "handshake_req_alloc all good",
+ .proto = &handshake_req_alloc_proto_good,
+ .gfp = GFP_KERNEL,
+ .expect_success = true,
+ },
+};
+
+static void
+handshake_req_alloc_get_desc(const struct handshake_req_alloc_test_param *param,
+ char *desc)
+{
+ strscpy(desc, param->desc, KUNIT_PARAM_DESC_SIZE);
+}
+
+/* Creates the function handshake_req_alloc_gen_params */
+KUNIT_ARRAY_PARAM(handshake_req_alloc, handshake_req_alloc_params,
+ handshake_req_alloc_get_desc);
+
+static void handshake_req_alloc_case(struct kunit *test)
+{
+ const struct handshake_req_alloc_test_param *param = test->param_value;
+ struct handshake_req *result;
+
+ /* Arrange */
+
+ /* Act */
+ result = handshake_req_alloc(param->proto, param->gfp);
+
+ /* Assert */
+ if (param->expect_success)
+ KUNIT_EXPECT_NOT_NULL(test, result);
+ else
+ KUNIT_EXPECT_NULL(test, result);
+
+ kfree(result);
+}
+
+static void handshake_req_submit_test1(struct kunit *test)
+{
+ struct socket *sock;
+ int err, result;
+
+ /* Arrange */
+ err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP,
+ &sock, 1);
+ KUNIT_ASSERT_EQ(test, err, 0);
+
+ /* Act */
+ result = handshake_req_submit(sock, NULL, GFP_KERNEL);
+
+ /* Assert */
+ KUNIT_EXPECT_EQ(test, result, -EINVAL);
+
+ sock_release(sock);
+}
+
+static void handshake_req_submit_test2(struct kunit *test)
+{
+ struct handshake_req *req;
+ int result;
+
+ /* Arrange */
+ req = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, req);
+
+ /* Act */
+ result = handshake_req_submit(NULL, req, GFP_KERNEL);
+
+ /* Assert */
+ KUNIT_EXPECT_EQ(test, result, -EINVAL);
+
+ /* handshake_req_submit() destroys @req on error */
+}
+
+static void handshake_req_submit_test3(struct kunit *test)
+{
+ struct handshake_req *req;
+ struct socket *sock;
+ int err, result;
+
+ /* Arrange */
+ req = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, req);
+
+ err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP,
+ &sock, 1);
+ KUNIT_ASSERT_EQ(test, err, 0);
+ sock->file = NULL;
+
+ /* Act */
+ result = handshake_req_submit(sock, req, GFP_KERNEL);
+
+ /* Assert */
+ KUNIT_EXPECT_EQ(test, result, -EINVAL);
+
+ /* handshake_req_submit() destroys @req on error */
+ sock_release(sock);
+}
+
+static void handshake_req_submit_test4(struct kunit *test)
+{
+ struct handshake_req *req, *result;
+ struct socket *sock;
+ int err;
+
+ /* Arrange */
+ req = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, req);
+
+ err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP,
+ &sock, 1);
+ KUNIT_ASSERT_EQ(test, err, 0);
+ sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file);
+ KUNIT_ASSERT_NOT_NULL(test, sock->sk);
+
+ err = handshake_req_submit(sock, req, GFP_KERNEL);
+ KUNIT_ASSERT_EQ(test, err, 0);
+
+ /* Act */
+ result = handshake_req_hash_lookup(sock->sk);
+
+ /* Assert */
+ KUNIT_EXPECT_NOT_NULL(test, result);
+ KUNIT_EXPECT_PTR_EQ(test, req, result);
+
+ handshake_req_cancel(sock->sk);
+ sock_release(sock);
+}
+
+static void handshake_req_submit_test5(struct kunit *test)
+{
+ struct handshake_req *req;
+ struct handshake_net *hn;
+ struct socket *sock;
+ struct net *net;
+ int saved, err;
+
+ /* Arrange */
+ req = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, req);
+
+ err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP,
+ &sock, 1);
+ KUNIT_ASSERT_EQ(test, err, 0);
+ sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file);
+ KUNIT_ASSERT_NOT_NULL(test, sock->sk);
+
+ net = sock_net(sock->sk);
+ hn = handshake_pernet(net);
+ KUNIT_ASSERT_NOT_NULL(test, hn);
+
+ saved = hn->hn_pending;
+ hn->hn_pending = hn->hn_pending_max + 1;
+
+ /* Act */
+ err = handshake_req_submit(sock, req, GFP_KERNEL);
+
+ /* Assert */
+ KUNIT_EXPECT_EQ(test, err, -EAGAIN);
+
+ sock_release(sock);
+ hn->hn_pending = saved;
+}
+
+static void handshake_req_submit_test6(struct kunit *test)
+{
+ struct handshake_req *req1, *req2;
+ struct socket *sock;
+ int err;
+
+ /* Arrange */
+ req1 = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, req1);
+ req2 = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, req2);
+
+ err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP,
+ &sock, 1);
+ KUNIT_ASSERT_EQ(test, err, 0);
+ sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file);
+ KUNIT_ASSERT_NOT_NULL(test, sock->sk);
+
+ /* Act */
+ err = handshake_req_submit(sock, req1, GFP_KERNEL);
+ KUNIT_ASSERT_EQ(test, err, 0);
+ err = handshake_req_submit(sock, req2, GFP_KERNEL);
+
+ /* Assert */
+ KUNIT_EXPECT_EQ(test, err, -EBUSY);
+
+ handshake_req_cancel(sock->sk);
+ sock_release(sock);
+}
+
+static void handshake_req_cancel_test1(struct kunit *test)
+{
+ struct handshake_req *req;
+ struct socket *sock;
+ bool result;
+ int err;
+
+ /* Arrange */
+ req = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, req);
+
+ err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP,
+ &sock, 1);
+ KUNIT_ASSERT_EQ(test, err, 0);
+
+ sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file);
+
+ err = handshake_req_submit(sock, req, GFP_KERNEL);
+ KUNIT_ASSERT_EQ(test, err, 0);
+
+ /* NB: handshake_req hasn't been accepted */
+
+ /* Act */
+ result = handshake_req_cancel(sock->sk);
+
+ /* Assert */
+ KUNIT_EXPECT_TRUE(test, result);
+
+ sock_release(sock);
+}
+
+static void handshake_req_cancel_test2(struct kunit *test)
+{
+ struct handshake_req *req, *next;
+ struct handshake_net *hn;
+ struct socket *sock;
+ struct net *net;
+ bool result;
+ int err;
+
+ /* Arrange */
+ req = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, req);
+
+ err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP,
+ &sock, 1);
+ KUNIT_ASSERT_EQ(test, err, 0);
+
+ sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file);
+
+ err = handshake_req_submit(sock, req, GFP_KERNEL);
+ KUNIT_ASSERT_EQ(test, err, 0);
+
+ net = sock_net(sock->sk);
+ hn = handshake_pernet(net);
+ KUNIT_ASSERT_NOT_NULL(test, hn);
+
+ /* Pretend to accept this request */
+ next = handshake_req_next(hn, HANDSHAKE_HANDLER_CLASS_TLSHD);
+ KUNIT_ASSERT_PTR_EQ(test, req, next);
+
+ /* Act */
+ result = handshake_req_cancel(sock->sk);
+
+ /* Assert */
+ KUNIT_EXPECT_TRUE(test, result);
+
+ sock_release(sock);
+}
+
+static void handshake_req_cancel_test3(struct kunit *test)
+{
+ struct handshake_req *req, *next;
+ struct handshake_net *hn;
+ struct socket *sock;
+ struct net *net;
+ bool result;
+ int err;
+
+ /* Arrange */
+ req = handshake_req_alloc(&handshake_req_alloc_proto_good, GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, req);
+
+ err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP,
+ &sock, 1);
+ KUNIT_ASSERT_EQ(test, err, 0);
+
+ sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file);
+
+ err = handshake_req_submit(sock, req, GFP_KERNEL);
+ KUNIT_ASSERT_EQ(test, err, 0);
+
+ net = sock_net(sock->sk);
+ hn = handshake_pernet(net);
+ KUNIT_ASSERT_NOT_NULL(test, hn);
+
+ /* Pretend to accept this request */
+ next = handshake_req_next(hn, HANDSHAKE_HANDLER_CLASS_TLSHD);
+ KUNIT_ASSERT_PTR_EQ(test, req, next);
+
+ /* Pretend to complete this request */
+ handshake_complete(next, -ETIMEDOUT, NULL);
+
+ /* Act */
+ result = handshake_req_cancel(sock->sk);
+
+ /* Assert */
+ KUNIT_EXPECT_FALSE(test, result);
+
+ sock_release(sock);
+}
+
+static struct handshake_req *handshake_req_destroy_test;
+
+static void test_destroy_func(struct handshake_req *req)
+{
+ handshake_req_destroy_test = req;
+}
+
+static struct handshake_proto handshake_req_alloc_proto_destroy = {
+ .hp_handler_class = HANDSHAKE_HANDLER_CLASS_TLSHD,
+ .hp_accept = test_accept_func,
+ .hp_done = test_done_func,
+ .hp_destroy = test_destroy_func,
+};
+
+static void handshake_req_destroy_test1(struct kunit *test)
+{
+ struct handshake_req *req;
+ struct socket *sock;
+ int err;
+
+ /* Arrange */
+ handshake_req_destroy_test = NULL;
+
+ req = handshake_req_alloc(&handshake_req_alloc_proto_destroy, GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, req);
+
+ err = __sock_create(&init_net, PF_INET, SOCK_STREAM, IPPROTO_TCP,
+ &sock, 1);
+ KUNIT_ASSERT_EQ(test, err, 0);
+
+ sock->file = sock_alloc_file(sock, O_NONBLOCK, NULL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sock->file);
+
+ err = handshake_req_submit(sock, req, GFP_KERNEL);
+ KUNIT_ASSERT_EQ(test, err, 0);
+
+ handshake_req_cancel(sock->sk);
+
+ /* Act */
+ sock_release(sock);
+
+ /* Assert */
+ KUNIT_EXPECT_PTR_EQ(test, handshake_req_destroy_test, req);
+}
+
+static struct kunit_case handshake_api_test_cases[] = {
+ {
+ .name = "req_alloc API fuzzing",
+ .run_case = handshake_req_alloc_case,
+ .generate_params = handshake_req_alloc_gen_params,
+ },
+ {
+ .name = "req_submit NULL req arg",
+ .run_case = handshake_req_submit_test1,
+ },
+ {
+ .name = "req_submit NULL sock arg",
+ .run_case = handshake_req_submit_test2,
+ },
+ {
+ .name = "req_submit NULL sock->file",
+ .run_case = handshake_req_submit_test3,
+ },
+ {
+ .name = "req_lookup works",
+ .run_case = handshake_req_submit_test4,
+ },
+ {
+ .name = "req_submit max pending",
+ .run_case = handshake_req_submit_test5,
+ },
+ {
+ .name = "req_submit multiple",
+ .run_case = handshake_req_submit_test6,
+ },
+ {
+ .name = "req_cancel before accept",
+ .run_case = handshake_req_cancel_test1,
+ },
+ {
+ .name = "req_cancel after accept",
+ .run_case = handshake_req_cancel_test2,
+ },
+ {
+ .name = "req_cancel after done",
+ .run_case = handshake_req_cancel_test3,
+ },
+ {
+ .name = "req_destroy works",
+ .run_case = handshake_req_destroy_test1,
+ },
+ {}
+};
+
+static struct kunit_suite handshake_api_suite = {
+ .name = "Handshake API tests",
+ .test_cases = handshake_api_test_cases,
+};
+
+kunit_test_suites(&handshake_api_suite);
+
+MODULE_DESCRIPTION("Test handshake upcall API functions");
+MODULE_LICENSE("GPL");
diff --git a/net/handshake/netlink.c b/net/handshake/netlink.c
index 23c8276654d6..68ce7bdfaa48 100644
--- a/net/handshake/netlink.c
+++ b/net/handshake/netlink.c
@@ -18,12 +18,31 @@
#include <net/genetlink.h>
#include <net/netns/generic.h>
+#include <kunit/visibility.h>
+
#include <uapi/linux/handshake.h>
#include "handshake.h"
#include "genl.h"
#include <trace/events/handshake.h>
+#if IS_ENABLED(CONFIG_KUNIT)
+
+/**
+ * handshake_genl_notify - Solve world hunger, tell no-one.
+ * @net: target network namespace
+ * @handler_class: target handler
+ * @flags: memory allocation control flags
+ *
+ * User agent generally isn't running during unit testing.
+ */
+int handshake_genl_notify(struct net *net, int handler_class, gfp_t flags)
+{
+ return 0;
+}
+
+#else
+
/**
* handshake_genl_notify - Notify handlers that a request is waiting
* @net: target network namespace
@@ -64,6 +83,8 @@ int handshake_genl_notify(struct net *net, int handler_class, gfp_t flags)
return -EMSGSIZE;
}
+#endif
+
/**
* handshake_genl_put - Create a generic netlink message header
* @msg: buffer in which to create the header
@@ -260,6 +281,7 @@ struct handshake_net *handshake_pernet(struct net *net)
return handshake_net_id ?
net_generic(net, handshake_net_id) : NULL;
}
+EXPORT_SYMBOL_IF_KUNIT(handshake_pernet);
static int __init handshake_init(void)
{
diff --git a/net/handshake/request.c b/net/handshake/request.c
index 494d4468aef8..8c777adeb818 100644
--- a/net/handshake/request.c
+++ b/net/handshake/request.c
@@ -20,6 +20,8 @@
#include <net/genetlink.h>
#include <net/netns/generic.h>
+#include <kunit/visibility.h>
+
#include <uapi/linux/handshake.h>
#include "handshake.h"
@@ -60,6 +62,7 @@ struct handshake_req *handshake_req_hash_lookup(struct sock *sk)
return rhashtable_lookup_fast(&handshake_rhashtbl, &sk,
handshake_rhash_params);
}
+EXPORT_SYMBOL_IF_KUNIT(handshake_req_hash_lookup);
static bool handshake_req_hash_add(struct handshake_req *req)
{
@@ -192,6 +195,7 @@ struct handshake_req *handshake_req_next(struct handshake_net *hn, int class)
return req;
}
+EXPORT_SYMBOL_IF_KUNIT(handshake_req_next);
/**
* handshake_req_submit - Submit a handshake request
@@ -294,6 +298,7 @@ void handshake_complete(struct handshake_req *req, unsigned int status,
sock_put(sk);
}
}
+EXPORT_SYMBOL_IF_KUNIT(handshake_complete);
/**
* handshake_req_cancel - Cancel an in-progress handshake
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