* [PATCH bpf-next v3 1/4] bpf: Be less specific about socket cookies guarantees
@ 2020-12-08 20:15 Florent Revest
2020-12-08 20:15 ` [PATCH bpf-next v3 2/4] bpf: Expose bpf_get_socket_cookie to tracing programs Florent Revest
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Florent Revest @ 2020-12-08 20:15 UTC (permalink / raw)
To: bpf; +Cc: ast, daniel, andrii, kpsingh, kafai, linux-kernel, Florent Revest
Since "92acdc58ab11 bpf, net: Rework cookie generator as per-cpu one"
socket cookies are not guaranteed to be non-decreasing. The
bpf_get_socket_cookie helper descriptions are currently specifying that
cookies are non-decreasing but we don't want users to rely on that.
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Florent Revest <revest@chromium.org>
---
include/uapi/linux/bpf.h | 8 ++++----
tools/include/uapi/linux/bpf.h | 8 ++++----
2 files changed, 8 insertions(+), 8 deletions(-)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 30b477a26482..ba59309f4d18 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1650,22 +1650,22 @@ union bpf_attr {
* networking traffic statistics as it provides a global socket
* identifier that can be assumed unique.
* Return
- * A 8-byte long non-decreasing number on success, or 0 if the
- * socket field is missing inside *skb*.
+ * A 8-byte long unique number on success, or 0 if the socket
+ * field is missing inside *skb*.
*
* u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx)
* Description
* Equivalent to bpf_get_socket_cookie() helper that accepts
* *skb*, but gets socket from **struct bpf_sock_addr** context.
* Return
- * A 8-byte long non-decreasing number.
+ * A 8-byte long unique number.
*
* u64 bpf_get_socket_cookie(struct bpf_sock_ops *ctx)
* Description
* Equivalent to **bpf_get_socket_cookie**\ () helper that accepts
* *skb*, but gets socket from **struct bpf_sock_ops** context.
* Return
- * A 8-byte long non-decreasing number.
+ * A 8-byte long unique number.
*
* u32 bpf_get_socket_uid(struct sk_buff *skb)
* Return
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 30b477a26482..ba59309f4d18 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -1650,22 +1650,22 @@ union bpf_attr {
* networking traffic statistics as it provides a global socket
* identifier that can be assumed unique.
* Return
- * A 8-byte long non-decreasing number on success, or 0 if the
- * socket field is missing inside *skb*.
+ * A 8-byte long unique number on success, or 0 if the socket
+ * field is missing inside *skb*.
*
* u64 bpf_get_socket_cookie(struct bpf_sock_addr *ctx)
* Description
* Equivalent to bpf_get_socket_cookie() helper that accepts
* *skb*, but gets socket from **struct bpf_sock_addr** context.
* Return
- * A 8-byte long non-decreasing number.
+ * A 8-byte long unique number.
*
* u64 bpf_get_socket_cookie(struct bpf_sock_ops *ctx)
* Description
* Equivalent to **bpf_get_socket_cookie**\ () helper that accepts
* *skb*, but gets socket from **struct bpf_sock_ops** context.
* Return
- * A 8-byte long non-decreasing number.
+ * A 8-byte long unique number.
*
* u32 bpf_get_socket_uid(struct sk_buff *skb)
* Return
--
2.29.2.576.ga3fc446d84-goog
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH bpf-next v3 2/4] bpf: Expose bpf_get_socket_cookie to tracing programs
2020-12-08 20:15 [PATCH bpf-next v3 1/4] bpf: Be less specific about socket cookies guarantees Florent Revest
@ 2020-12-08 20:15 ` Florent Revest
2020-12-08 22:08 ` KP Singh
2020-12-08 20:15 ` [PATCH bpf-next v3 3/4] selftests/bpf: Integrate the socket_cookie test to test_progs Florent Revest
2020-12-08 20:15 ` [PATCH bpf-next v3 4/4] selftests/bpf: Add a selftest for the tracing bpf_get_socket_cookie Florent Revest
2 siblings, 1 reply; 6+ messages in thread
From: Florent Revest @ 2020-12-08 20:15 UTC (permalink / raw)
To: bpf; +Cc: ast, daniel, andrii, kpsingh, kafai, linux-kernel, Florent Revest
This needs two new helpers, one that works in a sleepable context (using
sock_gen_cookie which disables/enables preemption) and one that does not
(for performance reasons). Both take a struct sock pointer and need to
check it for NULLness.
This helper could also be useful to other BPF program types such as LSM.
Signed-off-by: Florent Revest <revest@chromium.org>
---
include/linux/bpf.h | 2 ++
include/uapi/linux/bpf.h | 7 +++++++
kernel/trace/bpf_trace.c | 4 ++++
net/core/filter.c | 24 ++++++++++++++++++++++++
tools/include/uapi/linux/bpf.h | 7 +++++++
5 files changed, 44 insertions(+)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index d05e75ed8c1b..2ecda549b773 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1859,6 +1859,8 @@ extern const struct bpf_func_proto bpf_snprintf_btf_proto;
extern const struct bpf_func_proto bpf_per_cpu_ptr_proto;
extern const struct bpf_func_proto bpf_this_cpu_ptr_proto;
extern const struct bpf_func_proto bpf_ktime_get_coarse_ns_proto;
+extern const struct bpf_func_proto bpf_get_socket_ptr_cookie_sleepable_proto;
+extern const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto;
const struct bpf_func_proto *bpf_tracing_func_proto(
enum bpf_func_id func_id, const struct bpf_prog *prog);
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index ba59309f4d18..9ac66cf25959 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1667,6 +1667,13 @@ union bpf_attr {
* Return
* A 8-byte long unique number.
*
+ * u64 bpf_get_socket_cookie(void *sk)
+ * Description
+ * Equivalent to **bpf_get_socket_cookie**\ () helper that accepts
+ * *sk*, but gets socket from a BTF **struct sock**.
+ * Return
+ * A 8-byte long unique number.
+ *
* u32 bpf_get_socket_uid(struct sk_buff *skb)
* Return
* The owner UID of the socket associated to *skb*. If the socket
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 0cf0a6331482..99accc2146bc 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1778,6 +1778,10 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
return &bpf_sk_storage_get_tracing_proto;
case BPF_FUNC_sk_storage_delete:
return &bpf_sk_storage_delete_tracing_proto;
+ case BPF_FUNC_get_socket_cookie:
+ return prog->aux->sleepable ?
+ &bpf_get_socket_ptr_cookie_sleepable_proto :
+ &bpf_get_socket_ptr_cookie_proto;
#endif
case BPF_FUNC_seq_printf:
return prog->expected_attach_type == BPF_TRACE_ITER ?
diff --git a/net/core/filter.c b/net/core/filter.c
index 77001a35768f..34877796ab5b 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4631,6 +4631,30 @@ static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = {
.arg1_type = ARG_PTR_TO_CTX,
};
+BPF_CALL_1(bpf_get_socket_ptr_cookie_sleepable, struct sock *, sk)
+{
+ return sk ? sock_gen_cookie(sk) : 0;
+}
+
+const struct bpf_func_proto bpf_get_socket_ptr_cookie_sleepable_proto = {
+ .func = bpf_get_socket_ptr_cookie_sleepable,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
+};
+
+BPF_CALL_1(bpf_get_socket_ptr_cookie, struct sock *, sk)
+{
+ return sk ? __sock_gen_cookie(sk) : 0;
+}
+
+const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto = {
+ .func = bpf_get_socket_ptr_cookie,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
+};
+
BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
{
return __sock_gen_cookie(ctx->sk);
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index ba59309f4d18..9ac66cf25959 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -1667,6 +1667,13 @@ union bpf_attr {
* Return
* A 8-byte long unique number.
*
+ * u64 bpf_get_socket_cookie(void *sk)
+ * Description
+ * Equivalent to **bpf_get_socket_cookie**\ () helper that accepts
+ * *sk*, but gets socket from a BTF **struct sock**.
+ * Return
+ * A 8-byte long unique number.
+ *
* u32 bpf_get_socket_uid(struct sk_buff *skb)
* Return
* The owner UID of the socket associated to *skb*. If the socket
--
2.29.2.576.ga3fc446d84-goog
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH bpf-next v3 3/4] selftests/bpf: Integrate the socket_cookie test to test_progs
2020-12-08 20:15 [PATCH bpf-next v3 1/4] bpf: Be less specific about socket cookies guarantees Florent Revest
2020-12-08 20:15 ` [PATCH bpf-next v3 2/4] bpf: Expose bpf_get_socket_cookie to tracing programs Florent Revest
@ 2020-12-08 20:15 ` Florent Revest
2020-12-08 20:15 ` [PATCH bpf-next v3 4/4] selftests/bpf: Add a selftest for the tracing bpf_get_socket_cookie Florent Revest
2 siblings, 0 replies; 6+ messages in thread
From: Florent Revest @ 2020-12-08 20:15 UTC (permalink / raw)
To: bpf; +Cc: ast, daniel, andrii, kpsingh, kafai, linux-kernel, Florent Revest
Currently, the selftest for the BPF socket_cookie helpers is built and
run independently from test_progs. It's easy to forget and hard to
maintain.
This patch moves the socket cookies test into prog_tests/ and vastly
simplifies its logic by:
- rewriting the loading code with BPF skeletons
- rewriting the server/client code with network helpers
- rewriting the cgroup code with test__join_cgroup
- rewriting the error handling code with CHECKs
Signed-off-by: Florent Revest <revest@chromium.org>
---
tools/testing/selftests/bpf/Makefile | 3 +-
.../selftests/bpf/prog_tests/socket_cookie.c | 82 +++++++
.../selftests/bpf/progs/socket_cookie_prog.c | 2 -
.../selftests/bpf/test_socket_cookie.c | 208 ------------------
4 files changed, 83 insertions(+), 212 deletions(-)
create mode 100644 tools/testing/selftests/bpf/prog_tests/socket_cookie.c
delete mode 100644 tools/testing/selftests/bpf/test_socket_cookie.c
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index ac25ba5d0d6c..c21960d5f286 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -33,7 +33,7 @@ LDLIBS += -lcap -lelf -lz -lrt -lpthread
# Order correspond to 'make run_tests' order
TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \
test_verifier_log test_dev_cgroup \
- test_sock test_sockmap get_cgroup_id_user test_socket_cookie \
+ test_sock test_sockmap get_cgroup_id_user \
test_cgroup_storage \
test_netcnt test_tcpnotify_user test_sysctl \
test_progs-no_alu32 \
@@ -167,7 +167,6 @@ $(OUTPUT)/test_dev_cgroup: cgroup_helpers.c
$(OUTPUT)/test_skb_cgroup_id_user: cgroup_helpers.c
$(OUTPUT)/test_sock: cgroup_helpers.c
$(OUTPUT)/test_sock_addr: cgroup_helpers.c
-$(OUTPUT)/test_socket_cookie: cgroup_helpers.c
$(OUTPUT)/test_sockmap: cgroup_helpers.c
$(OUTPUT)/test_tcpnotify_user: cgroup_helpers.c trace_helpers.c
$(OUTPUT)/get_cgroup_id_user: cgroup_helpers.c
diff --git a/tools/testing/selftests/bpf/prog_tests/socket_cookie.c b/tools/testing/selftests/bpf/prog_tests/socket_cookie.c
new file mode 100644
index 000000000000..53d0c44e7907
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/socket_cookie.c
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2020 Google LLC.
+// Copyright (c) 2018 Facebook
+
+#include <test_progs.h>
+#include "socket_cookie_prog.skel.h"
+#include "network_helpers.h"
+
+static int duration;
+
+struct socket_cookie {
+ __u64 cookie_key;
+ __u32 cookie_value;
+};
+
+void test_socket_cookie(void)
+{
+ socklen_t addr_len = sizeof(struct sockaddr_in6);
+ struct bpf_link *set_link, *update_link;
+ int server_fd, client_fd, cgroup_fd;
+ struct socket_cookie_prog *skel;
+ __u32 cookie_expected_value;
+ struct sockaddr_in6 addr;
+ struct socket_cookie val;
+ int err = 0;
+
+ skel = socket_cookie_prog__open_and_load();
+ if (CHECK(!skel, "socket_cookie_prog__open_and_load",
+ "skeleton open_and_load failed\n"))
+ return;
+
+ cgroup_fd = test__join_cgroup("/socket_cookie");
+ if (CHECK(cgroup_fd < 0, "join_cgroup", "cgroup creation failed\n"))
+ goto destroy_skel;
+
+ set_link = bpf_program__attach_cgroup(skel->progs.set_cookie,
+ cgroup_fd);
+ if (CHECK(IS_ERR(set_link), "set-link-cg-attach", "err %ld\n",
+ PTR_ERR(set_link)))
+ goto close_cgroup_fd;
+
+ update_link = bpf_program__attach_cgroup(skel->progs.update_cookie,
+ cgroup_fd);
+ if (CHECK(IS_ERR(update_link), "update-link-cg-attach", "err %ld\n",
+ PTR_ERR(update_link)))
+ goto free_set_link;
+
+ server_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0);
+ if (CHECK(server_fd < 0, "start_server", "errno %d\n", errno))
+ goto free_update_link;
+
+ client_fd = connect_to_fd(server_fd, 0);
+ if (CHECK(client_fd < 0, "connect_to_fd", "errno %d\n", errno))
+ goto close_server_fd;
+
+ err = bpf_map_lookup_elem(bpf_map__fd(skel->maps.socket_cookies),
+ &client_fd, &val);
+ if (CHECK(err, "map_lookup", "err %d errno %d\n", err, errno))
+ goto close_client_fd;
+
+ err = getsockname(client_fd, (struct sockaddr *)&addr, &addr_len);
+ if (CHECK(err, "getsockname", "Can't get client local addr\n"))
+ goto close_client_fd;
+
+ cookie_expected_value = (ntohs(addr.sin6_port) << 8) | 0xFF;
+ CHECK(val.cookie_value != cookie_expected_value, "",
+ "Unexpected value in map: %x != %x\n", val.cookie_value,
+ cookie_expected_value);
+
+close_client_fd:
+ close(client_fd);
+close_server_fd:
+ close(server_fd);
+free_update_link:
+ bpf_link__destroy(update_link);
+free_set_link:
+ bpf_link__destroy(set_link);
+close_cgroup_fd:
+ close(cgroup_fd);
+destroy_skel:
+ socket_cookie_prog__destroy(skel);
+}
diff --git a/tools/testing/selftests/bpf/progs/socket_cookie_prog.c b/tools/testing/selftests/bpf/progs/socket_cookie_prog.c
index 0cb5656a22b0..81e84be6f86d 100644
--- a/tools/testing/selftests/bpf/progs/socket_cookie_prog.c
+++ b/tools/testing/selftests/bpf/progs/socket_cookie_prog.c
@@ -65,6 +65,4 @@ int update_cookie(struct bpf_sock_ops *ctx)
return 1;
}
-int _version SEC("version") = 1;
-
char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/test_socket_cookie.c b/tools/testing/selftests/bpf/test_socket_cookie.c
deleted file mode 100644
index ca7ca87e91aa..000000000000
--- a/tools/testing/selftests/bpf/test_socket_cookie.c
+++ /dev/null
@@ -1,208 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-// Copyright (c) 2018 Facebook
-
-#include <string.h>
-#include <unistd.h>
-
-#include <arpa/inet.h>
-#include <netinet/in.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-
-#include <bpf/bpf.h>
-#include <bpf/libbpf.h>
-
-#include "bpf_rlimit.h"
-#include "cgroup_helpers.h"
-
-#define CG_PATH "/foo"
-#define SOCKET_COOKIE_PROG "./socket_cookie_prog.o"
-
-struct socket_cookie {
- __u64 cookie_key;
- __u32 cookie_value;
-};
-
-static int start_server(void)
-{
- struct sockaddr_in6 addr;
- int fd;
-
- fd = socket(AF_INET6, SOCK_STREAM, 0);
- if (fd == -1) {
- log_err("Failed to create server socket");
- goto out;
- }
-
- memset(&addr, 0, sizeof(addr));
- addr.sin6_family = AF_INET6;
- addr.sin6_addr = in6addr_loopback;
- addr.sin6_port = 0;
-
- if (bind(fd, (const struct sockaddr *)&addr, sizeof(addr)) == -1) {
- log_err("Failed to bind server socket");
- goto close_out;
- }
-
- if (listen(fd, 128) == -1) {
- log_err("Failed to listen on server socket");
- goto close_out;
- }
-
- goto out;
-
-close_out:
- close(fd);
- fd = -1;
-out:
- return fd;
-}
-
-static int connect_to_server(int server_fd)
-{
- struct sockaddr_storage addr;
- socklen_t len = sizeof(addr);
- int fd;
-
- fd = socket(AF_INET6, SOCK_STREAM, 0);
- if (fd == -1) {
- log_err("Failed to create client socket");
- goto out;
- }
-
- if (getsockname(server_fd, (struct sockaddr *)&addr, &len)) {
- log_err("Failed to get server addr");
- goto close_out;
- }
-
- if (connect(fd, (const struct sockaddr *)&addr, len) == -1) {
- log_err("Fail to connect to server");
- goto close_out;
- }
-
- goto out;
-
-close_out:
- close(fd);
- fd = -1;
-out:
- return fd;
-}
-
-static int validate_map(struct bpf_map *map, int client_fd)
-{
- __u32 cookie_expected_value;
- struct sockaddr_in6 addr;
- socklen_t len = sizeof(addr);
- struct socket_cookie val;
- int err = 0;
- int map_fd;
-
- if (!map) {
- log_err("Map not found in BPF object");
- goto err;
- }
-
- map_fd = bpf_map__fd(map);
-
- err = bpf_map_lookup_elem(map_fd, &client_fd, &val);
-
- err = getsockname(client_fd, (struct sockaddr *)&addr, &len);
- if (err) {
- log_err("Can't get client local addr");
- goto out;
- }
-
- cookie_expected_value = (ntohs(addr.sin6_port) << 8) | 0xFF;
- if (val.cookie_value != cookie_expected_value) {
- log_err("Unexpected value in map: %x != %x", val.cookie_value,
- cookie_expected_value);
- goto err;
- }
-
- goto out;
-err:
- err = -1;
-out:
- return err;
-}
-
-static int run_test(int cgfd)
-{
- enum bpf_attach_type attach_type;
- struct bpf_prog_load_attr attr;
- struct bpf_program *prog;
- struct bpf_object *pobj;
- const char *prog_name;
- int server_fd = -1;
- int client_fd = -1;
- int prog_fd = -1;
- int err = 0;
-
- memset(&attr, 0, sizeof(attr));
- attr.file = SOCKET_COOKIE_PROG;
- attr.prog_type = BPF_PROG_TYPE_UNSPEC;
- attr.prog_flags = BPF_F_TEST_RND_HI32;
-
- err = bpf_prog_load_xattr(&attr, &pobj, &prog_fd);
- if (err) {
- log_err("Failed to load %s", attr.file);
- goto out;
- }
-
- bpf_object__for_each_program(prog, pobj) {
- prog_name = bpf_program__section_name(prog);
-
- if (libbpf_attach_type_by_name(prog_name, &attach_type))
- goto err;
-
- err = bpf_prog_attach(bpf_program__fd(prog), cgfd, attach_type,
- BPF_F_ALLOW_OVERRIDE);
- if (err) {
- log_err("Failed to attach prog %s", prog_name);
- goto out;
- }
- }
-
- server_fd = start_server();
- if (server_fd == -1)
- goto err;
-
- client_fd = connect_to_server(server_fd);
- if (client_fd == -1)
- goto err;
-
- if (validate_map(bpf_map__next(NULL, pobj), client_fd))
- goto err;
-
- goto out;
-err:
- err = -1;
-out:
- close(client_fd);
- close(server_fd);
- bpf_object__close(pobj);
- printf("%s\n", err ? "FAILED" : "PASSED");
- return err;
-}
-
-int main(int argc, char **argv)
-{
- int cgfd = -1;
- int err = 0;
-
- cgfd = cgroup_setup_and_join(CG_PATH);
- if (cgfd < 0)
- goto err;
-
- if (run_test(cgfd))
- goto err;
-
- goto out;
-err:
- err = -1;
-out:
- close(cgfd);
- cleanup_cgroup_environment();
- return err;
-}
--
2.29.2.576.ga3fc446d84-goog
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH bpf-next v3 4/4] selftests/bpf: Add a selftest for the tracing bpf_get_socket_cookie
2020-12-08 20:15 [PATCH bpf-next v3 1/4] bpf: Be less specific about socket cookies guarantees Florent Revest
2020-12-08 20:15 ` [PATCH bpf-next v3 2/4] bpf: Expose bpf_get_socket_cookie to tracing programs Florent Revest
2020-12-08 20:15 ` [PATCH bpf-next v3 3/4] selftests/bpf: Integrate the socket_cookie test to test_progs Florent Revest
@ 2020-12-08 20:15 ` Florent Revest
2 siblings, 0 replies; 6+ messages in thread
From: Florent Revest @ 2020-12-08 20:15 UTC (permalink / raw)
To: bpf; +Cc: ast, daniel, andrii, kpsingh, kafai, linux-kernel, Florent Revest
This builds up on the existing socket cookie test which checks whether
the bpf_get_socket_cookie helpers provide the same value in
cgroup/connect6 and sockops programs for a socket created by the
userspace part of the test.
Adding a tracing program to the existing objects requires a different
attachment strategy and different headers.
Signed-off-by: Florent Revest <revest@chromium.org>
---
.../selftests/bpf/prog_tests/socket_cookie.c | 24 +++++++----
.../selftests/bpf/progs/socket_cookie_prog.c | 41 ++++++++++++++++---
2 files changed, 52 insertions(+), 13 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/socket_cookie.c b/tools/testing/selftests/bpf/prog_tests/socket_cookie.c
index 53d0c44e7907..e5c5e2ea1deb 100644
--- a/tools/testing/selftests/bpf/prog_tests/socket_cookie.c
+++ b/tools/testing/selftests/bpf/prog_tests/socket_cookie.c
@@ -15,8 +15,8 @@ struct socket_cookie {
void test_socket_cookie(void)
{
+ struct bpf_link *set_link, *update_sockops_link, *update_tracing_link;
socklen_t addr_len = sizeof(struct sockaddr_in6);
- struct bpf_link *set_link, *update_link;
int server_fd, client_fd, cgroup_fd;
struct socket_cookie_prog *skel;
__u32 cookie_expected_value;
@@ -39,15 +39,21 @@ void test_socket_cookie(void)
PTR_ERR(set_link)))
goto close_cgroup_fd;
- update_link = bpf_program__attach_cgroup(skel->progs.update_cookie,
- cgroup_fd);
- if (CHECK(IS_ERR(update_link), "update-link-cg-attach", "err %ld\n",
- PTR_ERR(update_link)))
+ update_sockops_link = bpf_program__attach_cgroup(
+ skel->progs.update_cookie_sockops, cgroup_fd);
+ if (CHECK(IS_ERR(update_sockops_link), "update-sockops-link-cg-attach",
+ "err %ld\n", PTR_ERR(update_sockops_link)))
goto free_set_link;
+ update_tracing_link = bpf_program__attach(
+ skel->progs.update_cookie_tracing);
+ if (CHECK(IS_ERR(update_tracing_link), "update-tracing-link-attach",
+ "err %ld\n", PTR_ERR(update_tracing_link)))
+ goto free_update_sockops_link;
+
server_fd = start_server(AF_INET6, SOCK_STREAM, "::1", 0, 0);
if (CHECK(server_fd < 0, "start_server", "errno %d\n", errno))
- goto free_update_link;
+ goto free_update_tracing_link;
client_fd = connect_to_fd(server_fd, 0);
if (CHECK(client_fd < 0, "connect_to_fd", "errno %d\n", errno))
@@ -71,8 +77,10 @@ void test_socket_cookie(void)
close(client_fd);
close_server_fd:
close(server_fd);
-free_update_link:
- bpf_link__destroy(update_link);
+free_update_tracing_link:
+ bpf_link__destroy(update_tracing_link);
+free_update_sockops_link:
+ bpf_link__destroy(update_sockops_link);
free_set_link:
bpf_link__destroy(set_link);
close_cgroup_fd:
diff --git a/tools/testing/selftests/bpf/progs/socket_cookie_prog.c b/tools/testing/selftests/bpf/progs/socket_cookie_prog.c
index 81e84be6f86d..1f770b732cb1 100644
--- a/tools/testing/selftests/bpf/progs/socket_cookie_prog.c
+++ b/tools/testing/selftests/bpf/progs/socket_cookie_prog.c
@@ -1,11 +1,13 @@
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2018 Facebook
-#include <linux/bpf.h>
-#include <sys/socket.h>
+#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_endian.h>
+#include <bpf/bpf_tracing.h>
+
+#define AF_INET6 10
struct socket_cookie {
__u64 cookie_key;
@@ -19,6 +21,14 @@ struct {
__type(value, struct socket_cookie);
} socket_cookies SEC(".maps");
+/*
+ * These three programs get executed in a row on connect() syscalls. The
+ * userspace side of the test creates a client socket, issues a connect() on it
+ * and then checks that the local storage associated with this socket has:
+ * cookie_value == local_port << 8 | 0xFF
+ * The different parts of this cookie_value are appended by those hooks if they
+ * all agree on the output of bpf_get_socket_cookie().
+ */
SEC("cgroup/connect6")
int set_cookie(struct bpf_sock_addr *ctx)
{
@@ -32,14 +42,14 @@ int set_cookie(struct bpf_sock_addr *ctx)
if (!p)
return 1;
- p->cookie_value = 0xFF;
+ p->cookie_value = 0xF;
p->cookie_key = bpf_get_socket_cookie(ctx);
return 1;
}
SEC("sockops")
-int update_cookie(struct bpf_sock_ops *ctx)
+int update_cookie_sockops(struct bpf_sock_ops *ctx)
{
struct bpf_sock *sk;
struct socket_cookie *p;
@@ -60,9 +70,30 @@ int update_cookie(struct bpf_sock_ops *ctx)
if (p->cookie_key != bpf_get_socket_cookie(ctx))
return 1;
- p->cookie_value = (ctx->local_port << 8) | p->cookie_value;
+ p->cookie_value |= (ctx->local_port << 8);
return 1;
}
+SEC("fexit/inet_stream_connect")
+int BPF_PROG(update_cookie_tracing, struct socket *sock,
+ struct sockaddr *uaddr, int addr_len, int flags)
+{
+ struct socket_cookie *p;
+
+ if (uaddr->sa_family != AF_INET6)
+ return 0;
+
+ p = bpf_sk_storage_get(&socket_cookies, sock->sk, 0, 0);
+ if (!p)
+ return 0;
+
+ if (p->cookie_key != bpf_get_socket_cookie(sock->sk))
+ return 0;
+
+ p->cookie_value |= 0xF0;
+
+ return 0;
+}
+
char _license[] SEC("license") = "GPL";
--
2.29.2.576.ga3fc446d84-goog
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH bpf-next v3 2/4] bpf: Expose bpf_get_socket_cookie to tracing programs
2020-12-08 20:15 ` [PATCH bpf-next v3 2/4] bpf: Expose bpf_get_socket_cookie to tracing programs Florent Revest
@ 2020-12-08 22:08 ` KP Singh
2020-12-09 13:23 ` Florent Revest
0 siblings, 1 reply; 6+ messages in thread
From: KP Singh @ 2020-12-08 22:08 UTC (permalink / raw)
To: Florent Revest
Cc: bpf, ast, daniel, andrii, kpsingh, Martin KaFai Lau, linux-kernel
On Tue, Dec 8, 2020 at 9:20 PM Florent Revest <revest@chromium.org> wrote:
>
> This needs two new helpers, one that works in a sleepable context (using
> sock_gen_cookie which disables/enables preemption) and one that does not
> (for performance reasons). Both take a struct sock pointer and need to
> check it for NULLness.
>
> This helper could also be useful to other BPF program types such as LSM.
>
> Signed-off-by: Florent Revest <revest@chromium.org>
> ---
> include/linux/bpf.h | 2 ++
> include/uapi/linux/bpf.h | 7 +++++++
> kernel/trace/bpf_trace.c | 4 ++++
> net/core/filter.c | 24 ++++++++++++++++++++++++
> tools/include/uapi/linux/bpf.h | 7 +++++++
> 5 files changed, 44 insertions(+)
>
> diff --git a/include/linux/bpf.h b/include/linux/bpf.h
> index d05e75ed8c1b..2ecda549b773 100644
> --- a/include/linux/bpf.h
> +++ b/include/linux/bpf.h
> @@ -1859,6 +1859,8 @@ extern const struct bpf_func_proto bpf_snprintf_btf_proto;
> extern const struct bpf_func_proto bpf_per_cpu_ptr_proto;
> extern const struct bpf_func_proto bpf_this_cpu_ptr_proto;
> extern const struct bpf_func_proto bpf_ktime_get_coarse_ns_proto;
> +extern const struct bpf_func_proto bpf_get_socket_ptr_cookie_sleepable_proto;
> +extern const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto;
>
> const struct bpf_func_proto *bpf_tracing_func_proto(
> enum bpf_func_id func_id, const struct bpf_prog *prog);
> diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
> index ba59309f4d18..9ac66cf25959 100644
> --- a/include/uapi/linux/bpf.h
> +++ b/include/uapi/linux/bpf.h
> @@ -1667,6 +1667,13 @@ union bpf_attr {
> * Return
> * A 8-byte long unique number.
> *
> + * u64 bpf_get_socket_cookie(void *sk)
> + * Description
> + * Equivalent to **bpf_get_socket_cookie**\ () helper that accepts
> + * *sk*, but gets socket from a BTF **struct sock**.
> + * Return
> + * A 8-byte long unique number.
> + *
> * u32 bpf_get_socket_uid(struct sk_buff *skb)
> * Return
> * The owner UID of the socket associated to *skb*. If the socket
> diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
> index 0cf0a6331482..99accc2146bc 100644
> --- a/kernel/trace/bpf_trace.c
> +++ b/kernel/trace/bpf_trace.c
> @@ -1778,6 +1778,10 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
> return &bpf_sk_storage_get_tracing_proto;
> case BPF_FUNC_sk_storage_delete:
> return &bpf_sk_storage_delete_tracing_proto;
> + case BPF_FUNC_get_socket_cookie:
> + return prog->aux->sleepable ?
> + &bpf_get_socket_ptr_cookie_sleepable_proto :
> + &bpf_get_socket_ptr_cookie_proto;
> #endif
> case BPF_FUNC_seq_printf:
> return prog->expected_attach_type == BPF_TRACE_ITER ?
> diff --git a/net/core/filter.c b/net/core/filter.c
> index 77001a35768f..34877796ab5b 100644
> --- a/net/core/filter.c
> +++ b/net/core/filter.c
> @@ -4631,6 +4631,30 @@ static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = {
> .arg1_type = ARG_PTR_TO_CTX,
> };
>
> +BPF_CALL_1(bpf_get_socket_ptr_cookie_sleepable, struct sock *, sk)
> +{
> + return sk ? sock_gen_cookie(sk) : 0;
My understanding is you can simply always call sock_gen_cookie and not
have two protos.
This will disable preemption in sleepable programs and not have any effect
in non-sleepable programs since preemption will already be disabled.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH bpf-next v3 2/4] bpf: Expose bpf_get_socket_cookie to tracing programs
2020-12-08 22:08 ` KP Singh
@ 2020-12-09 13:23 ` Florent Revest
0 siblings, 0 replies; 6+ messages in thread
From: Florent Revest @ 2020-12-09 13:23 UTC (permalink / raw)
To: KP Singh
Cc: bpf, ast, daniel, andrii, kpsingh, Martin KaFai Lau, linux-kernel
On Tue, 2020-12-08 at 23:08 +0100, KP Singh wrote:
> My understanding is you can simply always call sock_gen_cookie and
> not have two protos.
>
> This will disable preemption in sleepable programs and not have any
> effect in non-sleepable programs since preemption will already be
> disabled.
Sure, that works. I thought that providing two helper implems would
slightly improve performances on non-sleepable programs but I can send
a v4 with only one helper that calls sock_gen_cookie.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2020-12-09 13:24 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-12-08 20:15 [PATCH bpf-next v3 1/4] bpf: Be less specific about socket cookies guarantees Florent Revest
2020-12-08 20:15 ` [PATCH bpf-next v3 2/4] bpf: Expose bpf_get_socket_cookie to tracing programs Florent Revest
2020-12-08 22:08 ` KP Singh
2020-12-09 13:23 ` Florent Revest
2020-12-08 20:15 ` [PATCH bpf-next v3 3/4] selftests/bpf: Integrate the socket_cookie test to test_progs Florent Revest
2020-12-08 20:15 ` [PATCH bpf-next v3 4/4] selftests/bpf: Add a selftest for the tracing bpf_get_socket_cookie Florent Revest
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