[PATCH bpf-next v3 09/10] selftests/bpf: move bpf_jit_harden helper into testing_helpers
From: Alexis Lothoré (eBPF Foundation)
Date: Wed Jul 01 2026 - 06:06:05 EST
Move set_bpf_jit_harden to testing helpers so that other selftests can
change the hardening configuration without re-implementing a helper.
Signed-off-by: Alexis Lothoré (eBPF Foundation) <alexis.lothore@xxxxxxxxxxx>
---
Changes in v3:
- new patch
---
.../selftests/bpf/prog_tests/bpf_insn_array.c | 41 ++--------------------
tools/testing/selftests/bpf/testing_helpers.c | 32 +++++++++++++++++
tools/testing/selftests/bpf/testing_helpers.h | 1 +
3 files changed, 36 insertions(+), 38 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_insn_array.c b/tools/testing/selftests/bpf/prog_tests/bpf_insn_array.c
index 0222a9a5d076..37c405fc2b0d 100644
--- a/tools/testing/selftests/bpf/prog_tests/bpf_insn_array.c
+++ b/tools/testing/selftests/bpf/prog_tests/bpf_insn_array.c
@@ -227,42 +227,6 @@ static void check_incorrect_index(void)
check_mid_insn_index();
}
-static int set_bpf_jit_harden(char *level)
-{
- char old_level;
- int err = -1;
- int fd = -1;
-
- fd = open("/proc/sys/net/core/bpf_jit_harden", O_RDWR | O_NONBLOCK);
- if (fd < 0) {
- ASSERT_FAIL("open .../bpf_jit_harden returned %d (errno=%d)", fd, errno);
- return -1;
- }
-
- err = read(fd, &old_level, 1);
- if (err != 1) {
- ASSERT_FAIL("read from .../bpf_jit_harden returned %d (errno=%d)", err, errno);
- err = -1;
- goto end;
- }
-
- lseek(fd, 0, SEEK_SET);
-
- err = write(fd, level, 1);
- if (err != 1) {
- ASSERT_FAIL("write to .../bpf_jit_harden returned %d (errno=%d)", err, errno);
- err = -1;
- goto end;
- }
-
- err = 0;
- *level = old_level;
-end:
- if (fd >= 0)
- close(fd);
- return err;
-}
-
static void check_blindness(void)
{
struct bpf_insn insns[] = {
@@ -272,7 +236,7 @@ static void check_blindness(void)
BPF_MOV64_IMM(BPF_REG_0, 1),
BPF_EXIT_INSN(),
};
- int prog_fd = -1, map_fd;
+ int prog_fd = -1, map_fd, ret;
struct bpf_insn_array_value val = {};
char bpf_jit_harden = '@'; /* non-exizsting value */
int i;
@@ -291,7 +255,8 @@ static void check_blindness(void)
goto cleanup;
bpf_jit_harden = '2';
- if (set_bpf_jit_harden(&bpf_jit_harden)) {
+ ret = set_bpf_jit_harden(&bpf_jit_harden);
+ if (!ASSERT_OK(ret, "set bpf_jit_harden")) {
bpf_jit_harden = '@'; /* open, read or write failed => no write was done */
goto cleanup;
}
diff --git a/tools/testing/selftests/bpf/testing_helpers.c b/tools/testing/selftests/bpf/testing_helpers.c
index c970e7793dfc..737f668b35e2 100644
--- a/tools/testing/selftests/bpf/testing_helpers.c
+++ b/tools/testing/selftests/bpf/testing_helpers.c
@@ -519,6 +519,38 @@ bool is_jit_enabled(void)
return enabled;
}
+int set_bpf_jit_harden(char *level)
+{
+ char old_level;
+ int err = -1;
+ int fd = -1;
+
+ fd = open("/proc/sys/net/core/bpf_jit_harden", O_RDWR | O_NONBLOCK);
+ if (fd < 0)
+ return -1;
+
+ err = read(fd, &old_level, 1);
+ if (err != 1) {
+ err = -1;
+ goto end;
+ }
+
+ lseek(fd, 0, SEEK_SET);
+
+ err = write(fd, level, 1);
+ if (err != 1) {
+ err = -1;
+ goto end;
+ }
+
+ err = 0;
+ *level = old_level;
+end:
+ if (fd >= 0)
+ close(fd);
+ return err;
+}
+
int stack_mprotect(void)
{
void *buf;
diff --git a/tools/testing/selftests/bpf/testing_helpers.h b/tools/testing/selftests/bpf/testing_helpers.h
index 2edc6fb7fc52..e00642afe86f 100644
--- a/tools/testing/selftests/bpf/testing_helpers.h
+++ b/tools/testing/selftests/bpf/testing_helpers.h
@@ -59,6 +59,7 @@ struct bpf_insn;
int get_xlated_program(int fd_prog, struct bpf_insn **buf, __u32 *cnt);
int testing_prog_flags(void);
bool is_jit_enabled(void);
+int set_bpf_jit_harden(char *level);
int stack_mprotect(void);
#endif /* __TESTING_HELPERS_H */
--
2.54.0