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-rw-r--r--arch/arm64/net/bpf_jit_comp.c2
-rw-r--r--tools/testing/selftests/bpf/prog_tests/exceptions.c1
-rw-r--r--tools/testing/selftests/bpf/progs/exceptions.c30
3 files changed, 33 insertions, 0 deletions
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
index c18e005a41db..c5f55d6161fe 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/arch/arm64/net/bpf_jit_comp.c
@@ -600,6 +600,8 @@ static int build_prologue(struct jit_ctx *ctx, bool ebpf_from_cbpf)
* 12 registers are on the stack
*/
emit(A64_SUB_I(1, A64_SP, A64_FP, 96), ctx);
+ /* The callback may use its own BPF stack, set up fp for it. */
+ ctx->fp_used = true;
}
/* Stack must be multiples of 16B */
diff --git a/tools/testing/selftests/bpf/prog_tests/exceptions.c b/tools/testing/selftests/bpf/prog_tests/exceptions.c
index 3588d6f97fd4..639866ce09a9 100644
--- a/tools/testing/selftests/bpf/prog_tests/exceptions.c
+++ b/tools/testing/selftests/bpf/prog_tests/exceptions.c
@@ -55,6 +55,7 @@ static void test_exceptions_success(void)
RUN_SUCCESS(exception_ext, 0);
RUN_SUCCESS(exception_ext_mod_cb_runtime, 35);
RUN_SUCCESS(exception_throw_subprog, 1);
+ RUN_SUCCESS(exception_throw_subprog_stack_cb, 0x1234);
RUN_SUCCESS(exception_assert_nz_gfunc, 1);
RUN_SUCCESS(exception_assert_zero_gfunc, 1);
RUN_SUCCESS(exception_assert_neg_gfunc, 1);
diff --git a/tools/testing/selftests/bpf/progs/exceptions.c b/tools/testing/selftests/bpf/progs/exceptions.c
index c8d716fbd419..91c81971e58c 100644
--- a/tools/testing/selftests/bpf/progs/exceptions.c
+++ b/tools/testing/selftests/bpf/progs/exceptions.c
@@ -212,6 +212,36 @@ int exception_throw_subprog(struct __sk_buff *ctx)
return 0;
}
+u64 exception_cb_stack_src = 0x1234;
+
+/*
+ * The address handed to the helper has to be this callback's own stack
+ * slot, not one from a frame that is already gone.
+ */
+__noinline int exception_cb_stack(u64 cookie)
+{
+ volatile u64 val = 0xdead;
+
+ bpf_probe_read_kernel((void *)&val, sizeof(val), &exception_cb_stack_src);
+ return val;
+}
+
+/* Throws from a subprogram that has a stack of its own. */
+__noinline static int throwing_subprog_stack(struct __sk_buff *ctx)
+{
+ volatile u64 pad[4] = {};
+
+ bpf_throw(pad[0]);
+ return 0;
+}
+
+SEC("tc")
+__exception_cb(exception_cb_stack)
+int exception_throw_subprog_stack_cb(struct __sk_buff *ctx)
+{
+ return throwing_subprog_stack(ctx);
+}
+
__noinline int assert_nz_gfunc(u64 c)
{
volatile u64 cookie = c;