| Message ID | 20210212205642.620788-5-me@ubique.spb.ru (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | BPF |
| Headers | show |
| Series | Add support of pointer to struct in global functions | expand |
On Fri, Feb 12, 2021 at 12:57 PM Dmitrii Banshchikov <me@ubique.spb.ru> wrote: > > test_global_func9 - check valid pointer's scenarios > test_global_func10 - check that a smaller type cannot be passed as a > larger one > test_global_func11 - check that CTX pointer cannot be passed > test_global_func12 - check access to a null pointer > test_global_func13 - check access to an arbitrary pointer value > test_global_func14 - check that an opaque pointer cannot be passed > test_global_func15 - check that a variable has an unknown value after > it was passed to a global function by pointer > test_global_func16 - check access to uninitialized stack memory > > test_global_func_args - check read and write operations through a pointer > > Signed-off-by: Dmitrii Banshchikov <me@ubique.spb.ru> > --- LGTM. Acked-by: Andrii Nakryiko <andrii@kernel.org> > .../bpf/prog_tests/global_func_args.c | 60 ++++++++ > .../bpf/prog_tests/test_global_funcs.c | 8 ++ > .../selftests/bpf/progs/test_global_func10.c | 29 ++++ > .../selftests/bpf/progs/test_global_func11.c | 19 +++ > .../selftests/bpf/progs/test_global_func12.c | 21 +++ > .../selftests/bpf/progs/test_global_func13.c | 24 ++++ > .../selftests/bpf/progs/test_global_func14.c | 21 +++ > .../selftests/bpf/progs/test_global_func15.c | 22 +++ > .../selftests/bpf/progs/test_global_func16.c | 22 +++ > .../selftests/bpf/progs/test_global_func9.c | 132 ++++++++++++++++++ > .../bpf/progs/test_global_func_args.c | 91 ++++++++++++ > 11 files changed, 449 insertions(+) > create mode 100644 tools/testing/selftests/bpf/prog_tests/global_func_args.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func10.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func11.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func12.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func13.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func14.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func15.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func16.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func9.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func_args.c > [...]
On Fri, Feb 12, 2021 at 12:57 PM Dmitrii Banshchikov <me@ubique.spb.ru> wrote: > > test_global_func9 - check valid pointer's scenarios > test_global_func10 - check that a smaller type cannot be passed as a > larger one > test_global_func11 - check that CTX pointer cannot be passed > test_global_func12 - check access to a null pointer > test_global_func13 - check access to an arbitrary pointer value > test_global_func14 - check that an opaque pointer cannot be passed > test_global_func15 - check that a variable has an unknown value after > it was passed to a global function by pointer > test_global_func16 - check access to uninitialized stack memory > > test_global_func_args - check read and write operations through a pointer > > Signed-off-by: Dmitrii Banshchikov <me@ubique.spb.ru> > --- > .../bpf/prog_tests/global_func_args.c | 60 ++++++++ > .../bpf/prog_tests/test_global_funcs.c | 8 ++ > .../selftests/bpf/progs/test_global_func10.c | 29 ++++ > .../selftests/bpf/progs/test_global_func11.c | 19 +++ > .../selftests/bpf/progs/test_global_func12.c | 21 +++ > .../selftests/bpf/progs/test_global_func13.c | 24 ++++ > .../selftests/bpf/progs/test_global_func14.c | 21 +++ > .../selftests/bpf/progs/test_global_func15.c | 22 +++ > .../selftests/bpf/progs/test_global_func16.c | 22 +++ > .../selftests/bpf/progs/test_global_func9.c | 132 ++++++++++++++++++ > .../bpf/progs/test_global_func_args.c | 91 ++++++++++++ > 11 files changed, 449 insertions(+) > create mode 100644 tools/testing/selftests/bpf/prog_tests/global_func_args.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func10.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func11.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func12.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func13.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func14.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func15.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func16.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func9.c > create mode 100644 tools/testing/selftests/bpf/progs/test_global_func_args.c > [...] > diff --git a/tools/testing/selftests/bpf/progs/test_global_func11.c b/tools/testing/selftests/bpf/progs/test_global_func11.c > new file mode 100644 > index 000000000000..28488047c849 > --- /dev/null > +++ b/tools/testing/selftests/bpf/progs/test_global_func11.c > @@ -0,0 +1,19 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +#include <stddef.h> > +#include <linux/bpf.h> > +#include <bpf/bpf_helpers.h> > + > +struct S { > + int x; > +}; > + > +__noinline int foo(const struct S *s) > +{ > + return s ? bpf_get_prandom_u32() < s->x : 0; > +} > + > +SEC("cgroup_skb/ingress") > +int test_cls(struct __sk_buff *skb) > +{ > + return foo(skb); This needs (void *) cast. It currently generates compilation warning: progs/test_global_func11.c:18:13: warning: incompatible pointer types passing 'struct __sk_buff *' to parameter of type 'const struct S *' [-Wincompatible-pointer-types] return foo(skb); ^~~ progs/test_global_func11.c:10:36: note: passing argument to parameter 's' here __noinline int foo(const struct S *s) ^ Please send a follow-up patch. > +} [...]
diff --git a/tools/testing/selftests/bpf/prog_tests/global_func_args.c b/tools/testing/selftests/bpf/prog_tests/global_func_args.c new file mode 100644 index 000000000000..8bcc2869102f --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/global_func_args.c @@ -0,0 +1,60 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "test_progs.h" +#include "network_helpers.h" + +static __u32 duration; + +static void test_global_func_args0(struct bpf_object *obj) +{ + int err, i, map_fd, actual_value; + const char *map_name = "values"; + + map_fd = bpf_find_map(__func__, obj, map_name); + if (CHECK(map_fd < 0, "bpf_find_map", "cannot find BPF map %s: %s\n", + map_name, strerror(errno))) + return; + + struct { + const char *descr; + int expected_value; + } tests[] = { + {"passing NULL pointer", 0}, + {"returning value", 1}, + {"reading local variable", 100 }, + {"writing local variable", 101 }, + {"reading global variable", 42 }, + {"writing global variable", 43 }, + {"writing to pointer-to-pointer", 1 }, + }; + + for (i = 0; i < ARRAY_SIZE(tests); ++i) { + const int expected_value = tests[i].expected_value; + + err = bpf_map_lookup_elem(map_fd, &i, &actual_value); + + CHECK(err || actual_value != expected_value, tests[i].descr, + "err %d result %d expected %d\n", err, actual_value, expected_value); + } +} + +void test_global_func_args(void) +{ + const char *file = "./test_global_func_args.o"; + __u32 retval; + struct bpf_object *obj; + int err, prog_fd; + + err = bpf_prog_load(file, BPF_PROG_TYPE_CGROUP_SKB, &obj, &prog_fd); + if (CHECK(err, "load program", "error %d loading %s\n", err, file)) + return; + + err = bpf_prog_test_run(prog_fd, 1, &pkt_v4, sizeof(pkt_v4), + NULL, NULL, &retval, &duration); + CHECK(err || retval, "pass global func args run", + "err %d errno %d retval %d duration %d\n", + err, errno, retval, duration); + + test_global_func_args0(obj); + + bpf_object__close(obj); +} diff --git a/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c b/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c index 32e4348b714b..7e13129f593a 100644 --- a/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c +++ b/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c @@ -61,6 +61,14 @@ void test_test_global_funcs(void) { "test_global_func6.o" , "modified ctx ptr R2" }, { "test_global_func7.o" , "foo() doesn't return scalar" }, { "test_global_func8.o" }, + { "test_global_func9.o" }, + { "test_global_func10.o", "invalid indirect read from stack" }, + { "test_global_func11.o", "Caller passes invalid args into func#1" }, + { "test_global_func12.o", "invalid mem access 'mem_or_null'" }, + { "test_global_func13.o", "Caller passes invalid args into func#1" }, + { "test_global_func14.o", "reference type('FWD S') size cannot be determined" }, + { "test_global_func15.o", "At program exit the register R0 has value" }, + { "test_global_func16.o", "invalid indirect read from stack" }, }; libbpf_print_fn_t old_print_fn = NULL; int err, i, duration = 0; diff --git a/tools/testing/selftests/bpf/progs/test_global_func10.c b/tools/testing/selftests/bpf/progs/test_global_func10.c new file mode 100644 index 000000000000..61c2ae92ce41 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_global_func10.c @@ -0,0 +1,29 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <stddef.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> + +struct Small { + int x; +}; + +struct Big { + int x; + int y; +}; + +__noinline int foo(const struct Big *big) +{ + if (big == 0) + return 0; + + return bpf_get_prandom_u32() < big->y; +} + +SEC("cgroup_skb/ingress") +int test_cls(struct __sk_buff *skb) +{ + const struct Small small = {.x = skb->len }; + + return foo((struct Big *)&small) ? 1 : 0; +} diff --git a/tools/testing/selftests/bpf/progs/test_global_func11.c b/tools/testing/selftests/bpf/progs/test_global_func11.c new file mode 100644 index 000000000000..28488047c849 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_global_func11.c @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <stddef.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> + +struct S { + int x; +}; + +__noinline int foo(const struct S *s) +{ + return s ? bpf_get_prandom_u32() < s->x : 0; +} + +SEC("cgroup_skb/ingress") +int test_cls(struct __sk_buff *skb) +{ + return foo(skb); +} diff --git a/tools/testing/selftests/bpf/progs/test_global_func12.c b/tools/testing/selftests/bpf/progs/test_global_func12.c new file mode 100644 index 000000000000..62343527cc59 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_global_func12.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <stddef.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> + +struct S { + int x; +}; + +__noinline int foo(const struct S *s) +{ + return bpf_get_prandom_u32() < s->x; +} + +SEC("cgroup_skb/ingress") +int test_cls(struct __sk_buff *skb) +{ + const struct S s = {.x = skb->len }; + + return foo(&s); +} diff --git a/tools/testing/selftests/bpf/progs/test_global_func13.c b/tools/testing/selftests/bpf/progs/test_global_func13.c new file mode 100644 index 000000000000..ff8897c1ac22 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_global_func13.c @@ -0,0 +1,24 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <stddef.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> + +struct S { + int x; +}; + +__noinline int foo(const struct S *s) +{ + if (s) + return bpf_get_prandom_u32() < s->x; + + return 0; +} + +SEC("cgroup_skb/ingress") +int test_cls(struct __sk_buff *skb) +{ + const struct S *s = (const struct S *)(0xbedabeda); + + return foo(s); +} diff --git a/tools/testing/selftests/bpf/progs/test_global_func14.c b/tools/testing/selftests/bpf/progs/test_global_func14.c new file mode 100644 index 000000000000..698c77199ebf --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_global_func14.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <stddef.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> + +struct S; + +__noinline int foo(const struct S *s) +{ + if (s) + return bpf_get_prandom_u32() < *(const int *) s; + + return 0; +} + +SEC("cgroup_skb/ingress") +int test_cls(struct __sk_buff *skb) +{ + + return foo(NULL); +} diff --git a/tools/testing/selftests/bpf/progs/test_global_func15.c b/tools/testing/selftests/bpf/progs/test_global_func15.c new file mode 100644 index 000000000000..c19c435988d5 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_global_func15.c @@ -0,0 +1,22 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <stddef.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> + +__noinline int foo(unsigned int *v) +{ + if (v) + *v = bpf_get_prandom_u32(); + + return 0; +} + +SEC("cgroup_skb/ingress") +int test_cls(struct __sk_buff *skb) +{ + unsigned int v = 1; + + foo(&v); + + return v; +} diff --git a/tools/testing/selftests/bpf/progs/test_global_func16.c b/tools/testing/selftests/bpf/progs/test_global_func16.c new file mode 100644 index 000000000000..0312d1e8d8c0 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_global_func16.c @@ -0,0 +1,22 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <stddef.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> + +__noinline int foo(int (*arr)[10]) +{ + if (arr) + return (*arr)[9]; + + return 0; +} + +SEC("cgroup_skb/ingress") +int test_cls(struct __sk_buff *skb) +{ + int array[10]; + + const int rv = foo(&array); + + return rv ? 1 : 0; +} diff --git a/tools/testing/selftests/bpf/progs/test_global_func9.c b/tools/testing/selftests/bpf/progs/test_global_func9.c new file mode 100644 index 000000000000..bd233ddede98 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_global_func9.c @@ -0,0 +1,132 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <stddef.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> + +struct S { + int x; +}; + +struct C { + int x; + int y; +}; + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, struct S); +} map SEC(".maps"); + +enum E { + E_ITEM +}; + +static int global_data_x = 100; +static int volatile global_data_y = 500; + +__noinline int foo(const struct S *s) +{ + if (s) + return bpf_get_prandom_u32() < s->x; + + return 0; +} + +__noinline int bar(int *x) +{ + if (x) + *x &= bpf_get_prandom_u32(); + + return 0; +} +__noinline int baz(volatile int *x) +{ + if (x) + *x &= bpf_get_prandom_u32(); + + return 0; +} + +__noinline int qux(enum E *e) +{ + if (e) + return *e; + + return 0; +} + +__noinline int quux(int (*arr)[10]) +{ + if (arr) + return (*arr)[9]; + + return 0; +} + +__noinline int quuz(int **p) +{ + if (p) + *p = NULL; + + return 0; +} + +SEC("cgroup_skb/ingress") +int test_cls(struct __sk_buff *skb) +{ + int result = 0; + + { + const struct S s = {.x = skb->len }; + + result |= foo(&s); + } + + { + const __u32 key = 1; + const struct S *s = bpf_map_lookup_elem(&map, &key); + + result |= foo(s); + } + + { + const struct C c = {.x = skb->len, .y = skb->family }; + + result |= foo((const struct S *)&c); + } + + { + result |= foo(NULL); + } + + { + bar(&result); + bar(&global_data_x); + } + + { + result |= baz(&global_data_y); + } + + { + enum E e = E_ITEM; + + result |= qux(&e); + } + + { + int array[10] = {0}; + + result |= quux(&array); + } + + { + int *p; + + result |= quuz(&p); + } + + return result ? 1 : 0; +} diff --git a/tools/testing/selftests/bpf/progs/test_global_func_args.c b/tools/testing/selftests/bpf/progs/test_global_func_args.c new file mode 100644 index 000000000000..cae309538a9e --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_global_func_args.c @@ -0,0 +1,91 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/bpf.h> + +#include <bpf/bpf_helpers.h> + +struct S { + int v; +}; + +static volatile struct S global_variable; + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(max_entries, 7); + __type(key, __u32); + __type(value, int); +} values SEC(".maps"); + +static void save_value(__u32 index, int value) +{ + bpf_map_update_elem(&values, &index, &value, 0); +} + +__noinline int foo(__u32 index, struct S *s) +{ + if (s) { + save_value(index, s->v); + return ++s->v; + } + + save_value(index, 0); + + return 1; +} + +__noinline int bar(__u32 index, volatile struct S *s) +{ + if (s) { + save_value(index, s->v); + return ++s->v; + } + + save_value(index, 0); + + return 1; +} + +__noinline int baz(struct S **s) +{ + if (s) + *s = 0; + + return 0; +} + +SEC("cgroup_skb/ingress") +int test_cls(struct __sk_buff *skb) +{ + __u32 index = 0; + + { + const int v = foo(index++, 0); + + save_value(index++, v); + } + + { + struct S s = { .v = 100 }; + + foo(index++, &s); + save_value(index++, s.v); + } + + { + global_variable.v = 42; + bar(index++, &global_variable); + save_value(index++, global_variable.v); + } + + { + struct S v, *p = &v; + + baz(&p); + save_value(index++, !p); + } + + return 0; +} + +char _license[] SEC("license") = "GPL";
test_global_func9 - check valid pointer's scenarios test_global_func10 - check that a smaller type cannot be passed as a larger one test_global_func11 - check that CTX pointer cannot be passed test_global_func12 - check access to a null pointer test_global_func13 - check access to an arbitrary pointer value test_global_func14 - check that an opaque pointer cannot be passed test_global_func15 - check that a variable has an unknown value after it was passed to a global function by pointer test_global_func16 - check access to uninitialized stack memory test_global_func_args - check read and write operations through a pointer Signed-off-by: Dmitrii Banshchikov <me@ubique.spb.ru> --- .../bpf/prog_tests/global_func_args.c | 60 ++++++++ .../bpf/prog_tests/test_global_funcs.c | 8 ++ .../selftests/bpf/progs/test_global_func10.c | 29 ++++ .../selftests/bpf/progs/test_global_func11.c | 19 +++ .../selftests/bpf/progs/test_global_func12.c | 21 +++ .../selftests/bpf/progs/test_global_func13.c | 24 ++++ .../selftests/bpf/progs/test_global_func14.c | 21 +++ .../selftests/bpf/progs/test_global_func15.c | 22 +++ .../selftests/bpf/progs/test_global_func16.c | 22 +++ .../selftests/bpf/progs/test_global_func9.c | 132 ++++++++++++++++++ .../bpf/progs/test_global_func_args.c | 91 ++++++++++++ 11 files changed, 449 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/global_func_args.c create mode 100644 tools/testing/selftests/bpf/progs/test_global_func10.c create mode 100644 tools/testing/selftests/bpf/progs/test_global_func11.c create mode 100644 tools/testing/selftests/bpf/progs/test_global_func12.c create mode 100644 tools/testing/selftests/bpf/progs/test_global_func13.c create mode 100644 tools/testing/selftests/bpf/progs/test_global_func14.c create mode 100644 tools/testing/selftests/bpf/progs/test_global_func15.c create mode 100644 tools/testing/selftests/bpf/progs/test_global_func16.c create mode 100644 tools/testing/selftests/bpf/progs/test_global_func9.c create mode 100644 tools/testing/selftests/bpf/progs/test_global_func_args.c