new file mode 100644
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "test_progs.h"
+#include "network_helpers.h"
+
+static void test_global_func_args0(struct bpf_object *obj, __u32 duration)
+{
+ int err, i, map_fd, actual_value;
+
+ map_fd = bpf_find_map(__func__, obj, "values");
+ if (CHECK_FAIL(map_fd < 0))
+ 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 duration = 0, 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, duration);
+
+ bpf_object__close(obj);
+}
@@ -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 off -8+4 size 8" },
+ { "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;
new file mode 100644
@@ -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;
+}
new file mode 100644
@@ -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);
+}
new file mode 100644
@@ -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);
+}
new file mode 100644
@@ -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);
+}
new file mode 100644
@@ -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);
+}
new file mode 100644
@@ -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;
+}
new file mode 100644
@@ -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;
+}
new file mode 100644
@@ -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;
+}
new file mode 100644
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/bpf.h>
+
+#include <bpf/bpf_helpers.h>
+
+struct S {
+ int v;
+};
+
+static 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(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;
+ foo(index++, &global_variable);
+ save_value(index++, global_variable.v);
+ }
+
+ {
+ struct S v, *p = &v;
+
+ bar(&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> --- v1 -> v2: - Test pointer to a global variable, array, enum, int - Test reading / writing values by pointers in global functions .../bpf/prog_tests/global_func_args.c | 56 ++++++++ .../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 | 79 +++++++++++ 11 files changed, 433 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