selftests/bpf: Add flexible array relocation tests

Add few tests validation CO-RE relocation handling of flexible array accesses.

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191215070844.1014385-3-andriin@fb.com

diff --git a/tools/testing/selftests/bpf/prog_tests/core_reloc.c b/tools/testing/selftests/bpf/prog_tests/core_reloc.c
index 05fe852..31e177a 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/core_reloc.c
+++ b/tools/testing/selftests/bpf/prog_tests/core_reloc.c
@@ -74,6 +74,7 @@
                .b123 = 2,                                              \
                .c1c  = 3,                                              \
                .d00d = 4,                                              \
+               .f10c = 0,                                              \
        },                                                              \
        .output_len = sizeof(struct core_reloc_arrays_output)           \
 }
@@ -308,12 +309,15 @@ static struct core_reloc_test_case test_cases[] = {
        ARRAYS_CASE(arrays),
        ARRAYS_CASE(arrays___diff_arr_dim),
        ARRAYS_CASE(arrays___diff_arr_val_sz),
+       ARRAYS_CASE(arrays___equiv_zero_sz_arr),
+       ARRAYS_CASE(arrays___fixed_arr),
 
        ARRAYS_ERR_CASE(arrays___err_too_small),
        ARRAYS_ERR_CASE(arrays___err_too_shallow),
        ARRAYS_ERR_CASE(arrays___err_non_array),
        ARRAYS_ERR_CASE(arrays___err_wrong_val_type1),
        ARRAYS_ERR_CASE(arrays___err_wrong_val_type2),
+       ARRAYS_ERR_CASE(arrays___err_bad_zero_sz_arr),
 
        /* enum/ptr/int handling scenarios */
        PRIMITIVES_CASE(primitives),

diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___equiv_zero_sz_arr.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___equiv_zero_sz_arr.c
new file mode 100644 (file)
index 0000000..65eac37
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___equiv_zero_sz_arr.c
@@ -0,0 +1,3 @@
+#include "core_reloc_types.h"
+
+void f(struct core_reloc_arrays___equiv_zero_sz_arr x) {}

diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_bad_zero_sz_arr.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_bad_zero_sz_arr.c
new file mode 100644 (file)
index 0000000..ecda2b5
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___err_bad_zero_sz_arr.c
@@ -0,0 +1,3 @@
+#include "core_reloc_types.h"
+
+void f(struct core_reloc_arrays___err_bad_zero_sz_arr x) {}

diff --git a/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___fixed_arr.c b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___fixed_arr.c
new file mode 100644 (file)
index 0000000..fe1d012
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/btf__core_reloc_arrays___fixed_arr.c
@@ -0,0 +1,3 @@
+#include "core_reloc_types.h"
+
+void f(struct core_reloc_arrays___fixed_arr x) {}

diff --git a/tools/testing/selftests/bpf/progs/core_reloc_types.h b/tools/testing/selftests/bpf/progs/core_reloc_types.h
index 9311489..6d598cf 100644 (file)
--- a/tools/testing/selftests/bpf/progs/core_reloc_types.h
+++ b/tools/testing/selftests/bpf/progs/core_reloc_types.h
@@ -327,6 +327,7 @@ struct core_reloc_arrays_output {
        char b123;
        int c1c;
        int d00d;
+       int f10c;
 };
 
 struct core_reloc_arrays_substruct {
@@ -339,6 +340,7 @@ struct core_reloc_arrays {
        char b[2][3][4];
        struct core_reloc_arrays_substruct c[3];
        struct core_reloc_arrays_substruct d[1][2];
+       struct core_reloc_arrays_substruct f[][2];
 };
 
 /* bigger array dimensions */
@@ -347,6 +349,7 @@ struct core_reloc_arrays___diff_arr_dim {
        char b[3][4][5];
        struct core_reloc_arrays_substruct c[4];
        struct core_reloc_arrays_substruct d[2][3];
+       struct core_reloc_arrays_substruct f[1][3];
 };
 
 /* different size of array's value (struct) */
@@ -363,6 +366,29 @@ struct core_reloc_arrays___diff_arr_val_sz {
                int d;
                int __padding2;
        } d[1][2];
+       struct {
+               int __padding1;
+               int c;
+               int __padding2;
+       } f[][2];
+};
+
+struct core_reloc_arrays___equiv_zero_sz_arr {
+       int a[5];
+       char b[2][3][4];
+       struct core_reloc_arrays_substruct c[3];
+       struct core_reloc_arrays_substruct d[1][2];
+       /* equivalent to flexible array */
+       struct core_reloc_arrays_substruct f[0][2];
+};
+
+struct core_reloc_arrays___fixed_arr {
+       int a[5];
+       char b[2][3][4];
+       struct core_reloc_arrays_substruct c[3];
+       struct core_reloc_arrays_substruct d[1][2];
+       /* not a flexible array anymore, but within access bounds */
+       struct core_reloc_arrays_substruct f[1][2];
 };
 
 struct core_reloc_arrays___err_too_small {
@@ -370,6 +396,7 @@ struct core_reloc_arrays___err_too_small {
        char b[2][3][4];
        struct core_reloc_arrays_substruct c[3];
        struct core_reloc_arrays_substruct d[1][2];
+       struct core_reloc_arrays_substruct f[][2];
 };
 
 struct core_reloc_arrays___err_too_shallow {
@@ -377,6 +404,7 @@ struct core_reloc_arrays___err_too_shallow {
        char b[2][3]; /* this one lacks one dimension */
        struct core_reloc_arrays_substruct c[3];
        struct core_reloc_arrays_substruct d[1][2];
+       struct core_reloc_arrays_substruct f[][2];
 };
 
 struct core_reloc_arrays___err_non_array {
@@ -384,6 +412,7 @@ struct core_reloc_arrays___err_non_array {
        char b[2][3][4];
        struct core_reloc_arrays_substruct c[3];
        struct core_reloc_arrays_substruct d[1][2];
+       struct core_reloc_arrays_substruct f[][2];
 };
 
 struct core_reloc_arrays___err_wrong_val_type {
@@ -391,6 +420,16 @@ struct core_reloc_arrays___err_wrong_val_type {
        char b[2][3][4];
        int c[3]; /* value is not a struct */
        struct core_reloc_arrays_substruct d[1][2];
+       struct core_reloc_arrays_substruct f[][2];
+};
+
+struct core_reloc_arrays___err_bad_zero_sz_arr {
+       /* zero-sized array, but not at the end */
+       struct core_reloc_arrays_substruct f[0][2];
+       int a[5];
+       char b[2][3][4];
+       struct core_reloc_arrays_substruct c[3];
+       struct core_reloc_arrays_substruct d[1][2];
 };
 
 /*

diff --git a/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c b/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c
index 89951b6..053b86f 100644 (file)
--- a/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c
+++ b/tools/testing/selftests/bpf/progs/test_core_reloc_arrays.c
@@ -18,6 +18,7 @@ struct core_reloc_arrays_output {
        char b123;
        int c1c;
        int d00d;
+       int f01c;
 };
 
 struct core_reloc_arrays_substruct {
@@ -30,6 +31,7 @@ struct core_reloc_arrays {
        char b[2][3][4];
        struct core_reloc_arrays_substruct c[3];
        struct core_reloc_arrays_substruct d[1][2];
+       struct core_reloc_arrays_substruct f[][2];
 };
 
 #define CORE_READ(dst, src) bpf_core_read(dst, sizeof(*(dst)), src)
@@ -40,18 +42,16 @@ int test_core_arrays(void *ctx)
        struct core_reloc_arrays *in = (void *)&data.in;
        struct core_reloc_arrays_output *out = (void *)&data.out;
 
-       /* in->a[2] */
        if (CORE_READ(&out->a2, &in->a[2]))
                return 1;
-       /* in->b[1][2][3] */
        if (CORE_READ(&out->b123, &in->b[1][2][3]))
                return 1;
-       /* in->c[1].c */
        if (CORE_READ(&out->c1c, &in->c[1].c))
                return 1;
-       /* in->d[0][0].d */
        if (CORE_READ(&out->d00d, &in->d[0][0].d))
                return 1;
+       if (CORE_READ(&out->f01c, &in->f[0][1].c))
+               return 1;
 
        return 0;
 }