1. Rename fs_kfuncs/xattr to fs_kfuncs/file_xattr and add a call of
bpf_get_dentry_xattr() to the test.
2. Add a new sub test fs_kfuncs/dentry_xattr, which checks 3 levels of
parent directories for xattr. This demonstrate the use case that
a xattr on a directory is used to tag all files in the directory and
sub directories.
Signed-off-by: Song Liu <song@xxxxxxxxxx>
---
.../selftests/bpf/prog_tests/fs_kfuncs.c | 61 +++++++++++++++++--
.../selftests/bpf/progs/test_dentry_xattr.c | 46 ++++++++++++++
.../selftests/bpf/progs/test_get_xattr.c | 16 ++++-
3 files changed, 117 insertions(+), 6 deletions(-)
create mode 100644 tools/testing/selftests/bpf/progs/test_dentry_xattr.c
diff --git a/tools/testing/selftests/bpf/prog_tests/fs_kfuncs.c b/tools/testing/selftests/bpf/prog_tests/fs_kfuncs.c
index 37056ba73847..a960cfbe8907 100644
--- a/tools/testing/selftests/bpf/prog_tests/fs_kfuncs.c
+++ b/tools/testing/selftests/bpf/prog_tests/fs_kfuncs.c
@@ -2,17 +2,19 @@
/* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */
#include <stdlib.h>
+#include <sys/stat.h>
#include <sys/types.h>
#include <sys/xattr.h>
#include <linux/fsverity.h>
#include <unistd.h>
#include <test_progs.h>
#include "test_get_xattr.skel.h"
+#include "test_dentry_xattr.skel.h"
#include "test_fsverity.skel.h"
static const char testfile[] = "/tmp/test_progs_fs_kfuncs";
-static void test_xattr(void)
+static void test_file_xattr(void)
{
struct test_get_xattr *skel = NULL;
int fd = -1, err;
@@ -50,7 +52,8 @@ static void test_xattr(void)
if (!ASSERT_GE(fd, 0, "open_file"))
goto out;
- ASSERT_EQ(skel->bss->found_xattr, 1, "found_xattr");
+ ASSERT_EQ(skel->bss->found_xattr_from_file, 1, "found_xattr_from_file");
+ ASSERT_EQ(skel->bss->found_xattr_from_dentry, 1, "found_xattr_from_dentry");
out:
close(fd);
@@ -58,6 +61,53 @@ static void test_xattr(void)
remove(testfile);
}
+static void test_directory_xattr(void)
+{
+ struct test_dentry_xattr *skel = NULL;
+ static const char * const paths[] = {
+ "/tmp/a",
+ "/tmp/a/b",
+ "/tmp/a/b/c",
+ };
+ const char *file = "/tmp/a/b/c/d";
+ int i, j, err, fd;
+
+ for (i = 0; i < sizeof(paths) / sizeof(char *); i++) {
+ err = mkdir(paths[i], 0755);
+ if (!ASSERT_OK(err, "mkdir"))
+ goto out;
+ err = setxattr(paths[i], "user.kfunc", "hello", sizeof("hello"), 0);
+ if (!ASSERT_OK(err, "setxattr")) {
+ i++;
+ goto out;
+ }
+ }
+
+ skel = test_dentry_xattr__open_and_load();
+
+ if (!ASSERT_OK_PTR(skel, "test_dentry_xattr__open_and_load"))
+ goto out;
+
+ skel->bss->monitored_pid = getpid();
+ err = test_dentry_xattr__attach(skel);
+
+ if (!ASSERT_OK(err, "test_dentry__xattr__attach"))
+ goto out;
+
+ fd = open(file, O_CREAT | O_RDONLY, 0644);
+ if (!ASSERT_GE(fd, 0, "open_file"))
+ goto out;
+
+ ASSERT_EQ(skel->bss->number_of_xattr_found, 3, "number_of_xattr_found");
+ close(fd);
+out:
+ test_dentry_xattr__destroy(skel);
+ remove(file);
+ for (j = i - 1; j >= 0; j--)
+ rmdir(paths[j]);
+}
+
+
#ifndef SHA256_DIGEST_SIZE
#define SHA256_DIGEST_SIZE 32
#endif
@@ -134,8 +184,11 @@ static void test_fsverity(void)
void test_fs_kfuncs(void)
{
- if (test__start_subtest("xattr"))
- test_xattr();
+ if (test__start_subtest("file_xattr"))
+ test_file_xattr();
+
+ if (test__start_subtest("dentry_xattr"))
+ test_directory_xattr();
if (test__start_subtest("fsverity"))
test_fsverity();
diff --git a/tools/testing/selftests/bpf/progs/test_dentry_xattr.c b/tools/testing/selftests/bpf/progs/test_dentry_xattr.c
new file mode 100644
index 000000000000..d2e378b2e2d5
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_dentry_xattr.c
@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */
+
+#include "vmlinux.h"
+#include <bpf/bpf_tracing.h>
+#include "bpf_kfuncs.h"
+
+char _license[] SEC("license") = "GPL";
+
+__u32 monitored_pid;
+__u32 number_of_xattr_found;
+
+static const char expected_value[] = "hello";
+char value[32];
+
+SEC("lsm.s/file_open")
+int BPF_PROG(test_file_open, struct file *f)
+{
+ struct bpf_dynptr value_ptr;
+ struct dentry *dentry, *prev_dentry;
+ __u32 pid, matches = 0;
+ int i, ret;
+
+ pid = bpf_get_current_pid_tgid() >> 32;
+ if (pid != monitored_pid)
+ return 0;
+
+ bpf_dynptr_from_mem(value, sizeof(value), 0, &value_ptr);
+
+ dentry = bpf_file_dentry(f);
+
+ for (i = 0; i < 10; i++) {
+ ret = bpf_get_dentry_xattr(dentry, "user.kfunc", &value_ptr);
+ if (ret == sizeof(expected_value) &&
+ !bpf_strncmp(value, ret, expected_value))
+ matches++;
+
+ prev_dentry = dentry;
+ dentry = bpf_dget_parent(prev_dentry);
+ bpf_dput(prev_dentry);
+ }
+
+ bpf_dput(dentry);
+ number_of_xattr_found = matches;
+ return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/test_get_xattr.c b/tools/testing/selftests/bpf/progs/test_get_xattr.c
index 7eb2a4e5a3e5..3b0dc6106ca5 100644
--- a/tools/testing/selftests/bpf/progs/test_get_xattr.c
+++ b/tools/testing/selftests/bpf/progs/test_get_xattr.c
@@ -9,7 +9,8 @@
char _license[] SEC("license") = "GPL";
__u32 monitored_pid;
-__u32 found_xattr;
+__u32 found_xattr_from_file;
+__u32 found_xattr_from_dentry;
static const char expected_value[] = "hello";
char value[32];
@@ -18,6 +19,7 @@ SEC("lsm.s/file_open")
int BPF_PROG(test_file_open, struct file *f)
{
struct bpf_dynptr value_ptr;
+ struct dentry *dentry;
__u32 pid;
int ret;
@@ -32,6 +34,16 @@ int BPF_PROG(test_file_open, struct file *f)
return 0;
if (bpf_strncmp(value, ret, expected_value))
return 0;
- found_xattr = 1;
+ found_xattr_from_file = 1;
+
+ dentry = bpf_file_dentry(f);
+ ret = bpf_get_dentry_xattr(dentry, "user.kfuncs", &value_ptr);
+ bpf_dput(dentry);
+ if (ret != sizeof(expected_value))
+ return 0;
+ if (bpf_strncmp(value, ret, expected_value))
+ return 0;
+ found_xattr_from_dentry = 1;
+
return 0;
}
--
2.43.0
