On Fri, Aug 23, 2024 at 11:49 AM Jordan Rome <linux@xxxxxxxxxxxxxx> wrote:
>
> This adds tests for both the happy path and
> the error path.
>
> Signed-off-by: Jordan Rome <linux@xxxxxxxxxxxxxx>
> ---
> .../selftests/bpf/prog_tests/attach_probe.c | 8 ++-
> .../selftests/bpf/prog_tests/read_vsyscall.c | 1 +
> .../selftests/bpf/progs/read_vsyscall.c | 9 ++-
> .../selftests/bpf/progs/test_attach_probe.c | 64 ++++++++++++++++++-
> 4 files changed, 75 insertions(+), 7 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/attach_probe.c b/tools/testing/selftests/bpf/prog_tests/attach_probe.c
> index 7175af39134f..329c7862b52d 100644
> --- a/tools/testing/selftests/bpf/prog_tests/attach_probe.c
> +++ b/tools/testing/selftests/bpf/prog_tests/attach_probe.c
> @@ -283,9 +283,11 @@ static void test_uprobe_sleepable(struct test_attach_probe *skel)
> trigger_func3();
>
> ASSERT_EQ(skel->bss->uprobe_byname3_sleepable_res, 9, "check_uprobe_byname3_sleepable_res");
> - ASSERT_EQ(skel->bss->uprobe_byname3_res, 10, "check_uprobe_byname3_res");
> - ASSERT_EQ(skel->bss->uretprobe_byname3_sleepable_res, 11, "check_uretprobe_byname3_sleepable_res");
> - ASSERT_EQ(skel->bss->uretprobe_byname3_res, 12, "check_uretprobe_byname3_res");
> + ASSERT_EQ(skel->bss->uprobe_byname3_str_sleepable_res, 10, "check_uprobe_byname3_str_sleepable_res");
> + ASSERT_EQ(skel->bss->uprobe_byname3_res, 11, "check_uprobe_byname3_res");
> + ASSERT_EQ(skel->bss->uretprobe_byname3_sleepable_res, 12, "check_uretprobe_byname3_sleepable_res");
> + ASSERT_EQ(skel->bss->uretprobe_byname3_str_sleepable_res, 13, "check_uretprobe_byname3_str_sleepable_res");
> + ASSERT_EQ(skel->bss->uretprobe_byname3_res, 14, "check_uretprobe_byname3_res");
> }
>
> void test_attach_probe(void)
> diff --git a/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c b/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c
> index 3405923fe4e6..c7b9ba8b1d06 100644
> --- a/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c
> +++ b/tools/testing/selftests/bpf/prog_tests/read_vsyscall.c
> @@ -23,6 +23,7 @@ struct read_ret_desc {
> { .name = "probe_read_user_str", .ret = -EFAULT },
> { .name = "copy_from_user", .ret = -EFAULT },
> { .name = "copy_from_user_task", .ret = -EFAULT },
> + { .name = "copy_from_user_str", .ret = -EFAULT },
> };
>
> void test_read_vsyscall(void)
> diff --git a/tools/testing/selftests/bpf/progs/read_vsyscall.c b/tools/testing/selftests/bpf/progs/read_vsyscall.c
> index 986f96687ae1..39ebef430059 100644
> --- a/tools/testing/selftests/bpf/progs/read_vsyscall.c
> +++ b/tools/testing/selftests/bpf/progs/read_vsyscall.c
> @@ -1,5 +1,6 @@
> // SPDX-License-Identifier: GPL-2.0
> /* Copyright (C) 2024. Huawei Technologies Co., Ltd */
> +#include "vmlinux.h"
> #include <linux/types.h>
> #include <bpf/bpf_helpers.h>
>
> @@ -7,10 +8,15 @@
>
> int target_pid = 0;
> void *user_ptr = 0;
> -int read_ret[8];
> +int read_ret[9];
>
> char _license[] SEC("license") = "GPL";
>
> +/*
> + * This is the only kfunc, the others are helpers
> + */
> +int bpf_copy_from_user_str(void *dst, u32, const void *, u64) __weak __ksym;
> +
> SEC("fentry/" SYS_PREFIX "sys_nanosleep")
> int do_probe_read(void *ctx)
> {
> @@ -40,6 +46,7 @@ int do_copy_from_user(void *ctx)
> read_ret[6] = bpf_copy_from_user(buf, sizeof(buf), user_ptr);
> 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);
>
> return 0;
> }
> diff --git a/tools/testing/selftests/bpf/progs/test_attach_probe.c b/tools/testing/selftests/bpf/progs/test_attach_probe.c
> index 68466a6ad18c..0b16502726f8 100644
> --- a/tools/testing/selftests/bpf/progs/test_attach_probe.c
> +++ b/tools/testing/selftests/bpf/progs/test_attach_probe.c
> @@ -5,6 +5,7 @@
> #include <bpf/bpf_helpers.h>
> #include <bpf/bpf_tracing.h>
> #include <bpf/bpf_core_read.h>
> +#include <errno.h>
> #include "bpf_misc.h"
>
> int kprobe2_res = 0;
> @@ -14,10 +15,15 @@ int uretprobe_byname_res = 0;
> int uprobe_byname2_res = 0;
> int uretprobe_byname2_res = 0;
> int uprobe_byname3_sleepable_res = 0;
> +int uprobe_byname3_str_sleepable_res = 0;
> int uprobe_byname3_res = 0;
> int uretprobe_byname3_sleepable_res = 0;
> +int uretprobe_byname3_str_sleepable_res = 0;
> int uretprobe_byname3_res = 0;
> void *user_ptr = 0;
> +u32 dynamic_sz = 1;
> +
> +int bpf_copy_from_user_str(void *dst, u32, const void *, u64) __weak __ksym;
>
> SEC("ksyscall/nanosleep")
> int BPF_KSYSCALL(handle_kprobe_auto, struct __kernel_timespec *req, struct __kernel_timespec *rem)
> @@ -87,11 +93,61 @@ static __always_inline bool verify_sleepable_user_copy(void)
> return bpf_strncmp(data, sizeof(data), "test_data") == 0;
> }
>
> +static __always_inline bool verify_sleepable_user_copy_str(void)
> +{
> + int ret;
> + char data_long[20];
> + char data_long_pad[20];
> + char data_long_err[20];
> + char data_short[4];
> + char data_short_pad[4];
> +
> + ret = bpf_copy_from_user_str(data_short, sizeof(data_short), user_ptr, 0);
> +
> + if (bpf_strncmp(data_short, 4, "tes\0") != 0 || ret != 4)
> + return false;
> +
> + ret = bpf_copy_from_user_str(data_short_pad, sizeof(data_short_pad), user_ptr, BPF_F_PAD_ZEROS);
> +
> + if (bpf_strncmp(data_short, 4, "tes\0") != 0 || ret != 4)
> + return false;
> +
> + // Make sure this passes the verifier
also please don't use C++-style comments
> + ret = bpf_copy_from_user_str(data_long, dynamic_sz &= sizeof(data_long), user_ptr, 0);
> +
> + if (ret != 0)
> + return false;
> +
> + ret = bpf_copy_from_user_str(data_long, sizeof(data_long), user_ptr, 0);
> +
> + if (bpf_strncmp(data_long, 10, "test_data\0") != 0 || ret != 10)
> + return false;
> +
> + ret = bpf_copy_from_user_str(data_long_pad, sizeof(data_long_pad), user_ptr, BPF_F_PAD_ZEROS);
> +
> + if (bpf_strncmp(data_long_pad, 10, "test_data\0") != 0 || ret != 10 || data_long_pad[19] != '\0')
> + return false;
> +
> + ret = bpf_copy_from_user_str(data_long_err, sizeof(data_long_err), (void *)data_long, BPF_F_PAD_ZEROS);
> +
> + if (ret > 0 || data_long_err[19] != '\0')
> + return false;
> +
> + ret = bpf_copy_from_user_str(data_long, sizeof(data_long), user_ptr, 2);
> +
> + if (ret != -EINVAL)
> + return false;
> +
> + return true;
> +}
> +
> SEC("uprobe.s//proc/self/exe:trigger_func3")
> int handle_uprobe_byname3_sleepable(struct pt_regs *ctx)
> {
> if (verify_sleepable_user_copy())
> uprobe_byname3_sleepable_res = 9;
> + if (verify_sleepable_user_copy_str())
> + uprobe_byname3_str_sleepable_res = 10;
> return 0;
> }
>
> @@ -102,7 +158,7 @@ int handle_uprobe_byname3_sleepable(struct pt_regs *ctx)
> SEC("uprobe//proc/self/exe:trigger_func3")
> int handle_uprobe_byname3(struct pt_regs *ctx)
> {
> - uprobe_byname3_res = 10;
> + uprobe_byname3_res = 11;
> return 0;
> }
>
> @@ -110,14 +166,16 @@ SEC("uretprobe.s//proc/self/exe:trigger_func3")
> int handle_uretprobe_byname3_sleepable(struct pt_regs *ctx)
> {
> if (verify_sleepable_user_copy())
> - uretprobe_byname3_sleepable_res = 11;
> + uretprobe_byname3_sleepable_res = 12;
> + if (verify_sleepable_user_copy_str())
> + uretprobe_byname3_str_sleepable_res = 13;
> return 0;
> }
>
> SEC("uretprobe//proc/self/exe:trigger_func3")
> int handle_uretprobe_byname3(struct pt_regs *ctx)
> {
> - uretprobe_byname3_res = 12;
> + uretprobe_byname3_res = 14;
> return 0;
> }
>
> --
> 2.43.5
>
