Merge branch 'support-array-presets-in-veristat'

Mykyta Yatsenko says:

====================
Support array presets in veristat

From: Mykyta Yatsenko <yatsenko@meta.com>

This patch series implements support for array variable presets in
veristat. Currently users can set values to global variables before
loading BPF program, but not for arrays. With this change array
elements are supported as well, for example:
```
sudo ./veristat set_global_vars.bpf.o -G "arr[0] = 1"
```

v4 -> v5
 * Simplify array elements offset calculation using  btf__resolve_size
 * Support white spaces in array indexes, e.g. arr [ 0 ]
 * Rename btf_find_member into adjust_var_secinfo_member

v3 -> v4
 * Rework implementation to support multi dimensional arrays
 * Rework data structures for storing parsed presets

v2 -> v3
 * Added more negative tests
 * Fix mem leak
 * Other small fixes

v1 -> v2
 * Support enums as indexes
 * Separating parsing logic from preset processing
 * Add more tests
====================

Link: https://patch.msgid.link/20250625165904.87820-1-mykyta.yatsenko5@gmail.com
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>

1 files changed, 122 insertions, 5 deletions

diff --git a/tools/testing/selftests/bpf/prog_tests/test_veristat.c b/tools/testing/selftests/bpf/prog_tests/test_veristat.c
index 47b56c258f3f..367f47e4a936 100644
--- a/tools/testing/selftests/bpf/prog_tests/test_veristat.c
+++ b/tools/testing/selftests/bpf/prog_tests/test_veristat.c
@@ -60,13 +60,19 @@ static void test_set_global_vars_succeeds(void)
 	    " -G \"var_s8 = -128\" "\
 	    " -G \"var_u8 = 255\" "\
 	    " -G \"var_ea = EA2\" "\
-	    " -G \"var_eb = EB2\" "\
-	    " -G \"var_ec = EC2\" "\
+	    " -G \"var_eb  =  EB2\" "\
+	    " -G \"var_ec=EC2\" "\
 	    " -G \"var_b = 1\" "\
-	    " -G \"struct1.struct2.u.var_u8 = 170\" "\
+	    " -G \"struct1[2].struct2[1][2].u.var_u8[2]=170\" "\
 	    " -G \"union1.struct3.var_u8_l = 0xaa\" "\
 	    " -G \"union1.struct3.var_u8_h = 0xaa\" "\
-	    "-vl2 > %s", fix->veristat, fix->tmpfile);
+	    " -G \"arr[3]= 171\" "	\
+	    " -G \"arr[EA2] =172\" "	\
+	    " -G \"enum_arr[EC2]=EA3\" " \
+	    " -G \"three_d[31][7][EA2]=173\"" \
+	    " -G \"struct1[2].struct2[1][2].u.mat[5][3]=174\" " \
+	    " -G \"struct11 [ 7 ] [ 5 ] .struct2[0][1].u.mat[3][0] = 175\" " \
+	    " -vl2 > %s", fix->veristat, fix->tmpfile);
 
 	read(fix->fd, fix->output, fix->sz);
 	__CHECK_STR("_w=0xf000000000000001 ", "var_s64 = 0xf000000000000001");
@@ -81,8 +87,14 @@ static void test_set_global_vars_succeeds(void)
 	__CHECK_STR("_w=12 ", "var_eb = EB2");
 	__CHECK_STR("_w=13 ", "var_ec = EC2");
 	__CHECK_STR("_w=1 ", "var_b = 1");
-	__CHECK_STR("_w=170 ", "struct1.struct2.u.var_u8 = 170");
+	__CHECK_STR("_w=170 ", "struct1[2].struct2[1][2].u.var_u8[2]=170");
 	__CHECK_STR("_w=0xaaaa ", "union1.var_u16 = 0xaaaa");
+	__CHECK_STR("_w=171 ", "arr[3]= 171");
+	__CHECK_STR("_w=172 ", "arr[EA2] =172");
+	__CHECK_STR("_w=10 ", "enum_arr[EC2]=EA3");
+	__CHECK_STR("_w=173 ", "matrix[31][7][11]=173");
+	__CHECK_STR("_w=174 ", "struct1[2].struct2[1][2].u.mat[5][3]=174");
+	__CHECK_STR("_w=175 ", "struct11[7][5].struct2[0][1].u.mat[3][0]=175");
 
 out:
 	teardown_fixture(fix);
@@ -129,6 +141,95 @@ out:
 	teardown_fixture(fix);
 }
 
+static void test_unsupported_ptr_array_type(void)
+{
+	struct fixture *fix = init_fixture();
+
+	SYS_FAIL(out,
+		 "%s set_global_vars.bpf.o -G \"ptr_arr[0] = 0\" -vl2 2> %s",
+		 fix->veristat, fix->tmpfile);
+
+	read(fix->fd, fix->output, fix->sz);
+	__CHECK_STR("Can't set ptr_arr[0]. Only ints and enums are supported", "ptr_arr");
+
+out:
+	teardown_fixture(fix);
+}
+
+static void test_array_out_of_bounds(void)
+{
+	struct fixture *fix = init_fixture();
+
+	SYS_FAIL(out,
+		 "%s set_global_vars.bpf.o -G \"arr[99] = 0\" -vl2 2> %s",
+		 fix->veristat, fix->tmpfile);
+
+	read(fix->fd, fix->output, fix->sz);
+	__CHECK_STR("Array index 99 is out of bounds", "arr[99]");
+
+out:
+	teardown_fixture(fix);
+}
+
+static void test_array_index_not_found(void)
+{
+	struct fixture *fix = init_fixture();
+
+	SYS_FAIL(out,
+		 "%s set_global_vars.bpf.o -G \"arr[EG2] = 0\" -vl2 2> %s",
+		 fix->veristat, fix->tmpfile);
+
+	read(fix->fd, fix->output, fix->sz);
+	__CHECK_STR("Can't resolve enum value EG2", "arr[EG2]");
+
+out:
+	teardown_fixture(fix);
+}
+
+static void test_array_index_for_non_array(void)
+{
+	struct fixture *fix = init_fixture();
+
+	SYS_FAIL(out,
+		 "%s set_global_vars.bpf.o -G \"var_b[0] = 1\" -vl2 2> %s",
+		 fix->veristat, fix->tmpfile);
+
+	pread(fix->fd, fix->output, fix->sz, 0);
+	__CHECK_STR("Array index is not expected for var_b", "var_b[0] = 1");
+
+	SYS_FAIL(out,
+		 "%s set_global_vars.bpf.o -G \"union1.struct3[0].var_u8_l=1\" -vl2 2> %s",
+		 fix->veristat, fix->tmpfile);
+
+	pread(fix->fd, fix->output, fix->sz, 0);
+	__CHECK_STR("Array index is not expected for struct3", "union1.struct3[0].var_u8_l=1");
+
+out:
+	teardown_fixture(fix);
+}
+
+static void test_no_array_index_for_array(void)
+{
+	struct fixture *fix = init_fixture();
+
+	SYS_FAIL(out,
+		 "%s set_global_vars.bpf.o -G \"arr = 1\" -vl2 2> %s",
+		 fix->veristat, fix->tmpfile);
+
+	pread(fix->fd, fix->output, fix->sz, 0);
+	__CHECK_STR("Can't set arr. Only ints and enums are supported", "arr = 1");
+
+	SYS_FAIL(out,
+		 "%s set_global_vars.bpf.o -G \"struct1[0].struct2.u.var_u8[2]=1\" -vl2 2> %s",
+		 fix->veristat, fix->tmpfile);
+
+	pread(fix->fd, fix->output, fix->sz, 0);
+	__CHECK_STR("Can't resolve field u for non-composite type", "struct1[0].struct2.u.var_u8[2]=1");
+
+out:
+	teardown_fixture(fix);
+}
+
 void test_veristat(void)
 {
 	if (test__start_subtest("set_global_vars_succeeds"))
@@ -139,6 +240,22 @@ void test_veristat(void)
 
 	if (test__start_subtest("set_global_vars_from_file_succeeds"))
 		test_set_global_vars_from_file_succeeds();
+
+	if (test__start_subtest("test_unsupported_ptr_array_type"))
+		test_unsupported_ptr_array_type();
+
+	if (test__start_subtest("test_array_out_of_bounds"))
+		test_array_out_of_bounds();
+
+	if (test__start_subtest("test_array_index_not_found"))
+		test_array_index_not_found();
+
+	if (test__start_subtest("test_array_index_for_non_array"))
+		test_array_index_for_non_array();
+
+	if (test__start_subtest("test_no_array_index_for_array"))
+		test_no_array_index_for_array();
+
 }
 
 #undef __CHECK_STR