s390/bpf: Fix indirect trampoline generation

The func_addr used to be NULL for indirect trampolines used by struct_ops.
Now func_addr is a valid function pointer.
Hence use BPF_TRAMP_F_INDIRECT flag to detect such condition.

Fixes: 2cd3e3772e41 ("x86/cfi,bpf: Fix bpf_struct_ops CFI")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/bpf/20231216004549.78355-1-alexei.starovoitov@gmail.com

diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index cc129617480a257038942a121b0ff2d02bb415d7..7f0a7b97ef4ce7c7a4c5eb92772d4e06626fe576 100644 (file)
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -2362,7 +2362,8 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
                return -ENOTSUPP;
 
        /* Return to %r14, since func_addr and %r0 are not available. */
-       if (!func_addr && !(flags & BPF_TRAMP_F_ORIG_STACK))
+       if ((!func_addr && !(flags & BPF_TRAMP_F_ORIG_STACK)) ||
+           (flags & BPF_TRAMP_F_INDIRECT))
                flags |= BPF_TRAMP_F_SKIP_FRAME;
 
        /*

diff --git a/tools/testing/selftests/bpf/DENYLIST.s390x b/tools/testing/selftests/bpf/DENYLIST.s390x
index d27aa42d11a49c397681e4a15bc815daa5019fe5..1a63996c0304bc76c6a3727340c1c63c029a5ac5 100644 (file)
--- a/tools/testing/selftests/bpf/DENYLIST.s390x
+++ b/tools/testing/selftests/bpf/DENYLIST.s390x
@@ -1,7 +1,5 @@
 # TEMPORARY
 # Alphabetical order
-dummy_st_ops/dummy_init_ret_value
-dummy_st_ops/dummy_init_ptr_arg
 exceptions                              # JIT does not support calling kfunc bpf_throw                                (exceptions)
 get_stack_raw_tp                         # user_stack corrupted user stack                                             (no backchain userspace)
 stacktrace_build_id                      # compare_map_keys stackid_hmap vs. stackmap err -2 errno 2                   (?)