On Fri, Aug 23, 2024 at 3:00 PM Andrii Nakryiko
<andrii.nakryiko@xxxxxxxxx> wrote:
>
> 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
>
Good catch. Will fix.
> > + 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
> >
