From: Jordan Rome <linux@jordanrome.com>
To: bpf@vger.kernel.org
Cc: linux-mm@kvack.org, Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
Andrii Nakryiko <andrii@kernel.org>,
Kernel Team <kernel-team@fb.com>,
Andrew Morton <akpm@linux-foundation.org>,
Shakeel Butt <shakeel.butt@linux.dev>
Subject: [bpf-next v2 2/2] selftests/bpf: Add tests for bpf_copy_from_user_task_str
Date: Mon, 6 Jan 2025 18:06:32 -0800 [thread overview]
Message-ID: <20250107020632.170883-2-linux@jordanrome.com> (raw)
In-Reply-To: <20250107020632.170883-1-linux@jordanrome.com>
This adds tests for both the happy path and the
error path (with and without the BPF_F_PAD_ZEROS flag).
Signed-off-by: Jordan Rome <linux@jordanrome.com>
---
.../selftests/bpf/prog_tests/bpf_iter.c | 7 +++
.../selftests/bpf/prog_tests/read_vsyscall.c | 1 +
.../selftests/bpf/progs/bpf_iter_tasks.c | 55 +++++++++++++++++++
.../selftests/bpf/progs/read_vsyscall.c | 6 +-
4 files changed, 67 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
index 6f1bfacd7375..8ed864793bd1 100644
--- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
+++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
@@ -34,6 +34,8 @@
#include "bpf_iter_ksym.skel.h"
#include "bpf_iter_sockmap.skel.h"
+static char test_data[] = "test_data";
+
static void test_btf_id_or_null(void)
{
struct bpf_iter_test_kern3 *skel;
@@ -328,12 +330,17 @@ static void test_task_sleepable(void)
if (!ASSERT_OK_PTR(skel, "bpf_iter_tasks__open_and_load"))
return;
+ skel->bss->user_ptr = test_data;
do_dummy_read(skel->progs.dump_task_sleepable);
ASSERT_GT(skel->bss->num_expected_failure_copy_from_user_task, 0,
"num_expected_failure_copy_from_user_task");
ASSERT_GT(skel->bss->num_success_copy_from_user_task, 0,
"num_success_copy_from_user_task");
+ ASSERT_GT(skel->bss->num_expected_failure_copy_from_user_task_str, 0,
+ "num_expected_failure_copy_from_user_task_str");
+ ASSERT_GT(skel->bss->num_success_copy_from_user_task_str, 0,
+ "num_success_copy_from_user_task_str");
bpf_iter_tasks__destroy(skel);
}
diff --git a/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c b/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c
index c7b9ba8b1d06..a8d1eaa67020 100644
--- a/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c
+++ b/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c
@@ -24,6 +24,7 @@ struct read_ret_desc {
{ .name = "copy_from_user", .ret = -EFAULT },
{ .name = "copy_from_user_task", .ret = -EFAULT },
{ .name = "copy_from_user_str", .ret = -EFAULT },
+ { .name = "copy_from_user_task_str", .ret = -EFAULT },
};
void test_read_vsyscall(void)
diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_tasks.c b/tools/testing/selftests/bpf/progs/bpf_iter_tasks.c
index bc10c4e4b4fa..90691e34b915 100644
--- a/tools/testing/selftests/bpf/progs/bpf_iter_tasks.c
+++ b/tools/testing/selftests/bpf/progs/bpf_iter_tasks.c
@@ -9,6 +9,7 @@ char _license[] SEC("license") = "GPL";
uint32_t tid = 0;
int num_unknown_tid = 0;
int num_known_tid = 0;
+void *user_ptr = 0;
SEC("iter/task")
int dump_task(struct bpf_iter__task *ctx)
@@ -35,7 +36,9 @@ int dump_task(struct bpf_iter__task *ctx)
}
int num_expected_failure_copy_from_user_task = 0;
+int num_expected_failure_copy_from_user_task_str = 0;
int num_success_copy_from_user_task = 0;
+int num_success_copy_from_user_task_str = 0;
SEC("iter.s/task")
int dump_task_sleepable(struct bpf_iter__task *ctx)
@@ -44,6 +47,9 @@ int dump_task_sleepable(struct bpf_iter__task *ctx)
struct task_struct *task = ctx->task;
static const char info[] = " === END ===";
struct pt_regs *regs;
+ char task_str1[10] = "aaaaaaaaaa";
+ char task_str2[10], task_str3[10];
+ char task_str4[20] = "aaaaaaaaaaaaaaaaaaaa";
void *ptr;
uint32_t user_data = 0;
int ret;
@@ -78,8 +84,57 @@ int dump_task_sleepable(struct bpf_iter__task *ctx)
BPF_SEQ_PRINTF(seq, "%s\n", info);
return 0;
}
+
++num_success_copy_from_user_task;
+ /* Read an invalid pointer and ensure we get an error */
+ ptr = NULL;
+ ret = bpf_copy_from_user_task_str((char *)task_str1, sizeof(task_str1), ptr, task, 0);
+ if (ret >= 0 || task_str1[9] != 'a') {
+ BPF_SEQ_PRINTF(seq, "%s\n", info);
+ return 0;
+ }
+
+ /* Read an invalid pointer and ensure we get error with pad zeros flag */
+ ptr = NULL;
+ ret = bpf_copy_from_user_task_str((char *)task_str1, sizeof(task_str1), ptr, task, BPF_F_PAD_ZEROS);
+ if (ret >= 0 || task_str1[9] != '\0') {
+ BPF_SEQ_PRINTF(seq, "%s\n", info);
+ return 0;
+ }
+
+ ++num_expected_failure_copy_from_user_task_str;
+
+ /* Same length as the string */
+ ret = bpf_copy_from_user_task_str((char *)task_str2, 10, user_ptr, task, 0);
+ if (bpf_strncmp(task_str2, 10, "test_data\0") != 0 || ret != 10) {
+ BPF_SEQ_PRINTF(seq, "%s\n", info);
+ return 0;
+ }
+
+ /* Shorter length than the string */
+ ret = bpf_copy_from_user_task_str((char *)task_str3, 9, user_ptr, task, 0);
+ if (bpf_strncmp(task_str3, 9, "test_dat\0") != 0 || ret != 9) {
+ BPF_SEQ_PRINTF(seq, "%s\n", info);
+ return 0;
+ }
+
+ /* Longer length than the string */
+ ret = bpf_copy_from_user_task_str((char *)task_str4, 20, user_ptr, task, 0);
+ if (bpf_strncmp(task_str4, 10, "test_data\0") != 0 || ret != 10 || task_str4[sizeof(task_str4) - 1] != 'a') {
+ BPF_SEQ_PRINTF(seq, "%s\n", info);
+ return 0;
+ }
+
+ /* Longer length than the string with pad zeros flag */
+ ret = bpf_copy_from_user_task_str((char *)task_str4, 20, user_ptr, task, BPF_F_PAD_ZEROS);
+ if (bpf_strncmp(task_str4, 10, "test_data\0") != 0 || ret != 10 || task_str4[sizeof(task_str4) - 1] != '\0') {
+ BPF_SEQ_PRINTF(seq, "%s\n", info);
+ return 0;
+ }
+
+ ++num_success_copy_from_user_task_str;
+
if (ctx->meta->seq_num == 0)
BPF_SEQ_PRINTF(seq, " tgid gid data\n");
diff --git a/tools/testing/selftests/bpf/progs/read_vsyscall.c b/tools/testing/selftests/bpf/progs/read_vsyscall.c
index 39ebef430059..623c1c5bd2d0 100644
--- a/tools/testing/selftests/bpf/progs/read_vsyscall.c
+++ b/tools/testing/selftests/bpf/progs/read_vsyscall.c
@@ -8,14 +8,15 @@
int target_pid = 0;
void *user_ptr = 0;
-int read_ret[9];
+int read_ret[10];
char _license[] SEC("license") = "GPL";
/*
- * This is the only kfunc, the others are helpers
+ * These are the kfuncs, the others are helpers
*/
int bpf_copy_from_user_str(void *dst, u32, const void *, u64) __weak __ksym;
+int bpf_copy_from_user_task_str(void *dst, u32, const void *, struct task_struct *, u64) __weak __ksym;
SEC("fentry/" SYS_PREFIX "sys_nanosleep")
int do_probe_read(void *ctx)
@@ -47,6 +48,7 @@ int do_copy_from_user(void *ctx)
read_ret[7] = bpf_copy_from_user_task(buf, sizeof(buf), user_ptr,
bpf_get_current_task_btf(), 0);
read_ret[8] = bpf_copy_from_user_str((char *)buf, sizeof(buf), user_ptr, 0);
+ read_ret[9] = bpf_copy_from_user_task_str((char *)buf, sizeof(buf), user_ptr, bpf_get_current_task_btf(), 0);
return 0;
}
--
2.43.5
next prev parent reply other threads:[~2025-01-07 2:07 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-01-07 2:06 [bpf-next v2 1/2] bpf: Add bpf_copy_from_user_task_str kfunc Jordan Rome
2025-01-07 2:06 ` Jordan Rome [this message]
2025-01-10 22:01 ` [bpf-next v2 2/2] selftests/bpf: Add tests for bpf_copy_from_user_task_str Andrii Nakryiko
2025-01-16 4:57 ` kernel test robot
2025-01-09 1:13 ` [bpf-next v2 1/2] bpf: Add bpf_copy_from_user_task_str kfunc kernel test robot
2025-01-10 0:48 ` kernel test robot
2025-01-10 21:50 ` Andrii Nakryiko
2025-01-17 2:22 ` Jordan Rome
2025-01-17 18:26 ` Andrii Nakryiko
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