From: Eduard Zingerman Date: Thu, 22 Aug 2024 08:41:10 +0000 (-0700) Subject: bpf: allow bpf_fastcall for bpf_cast_to_kern_ctx and bpf_rdonly_cast X-Git-Tag: v6.12-rc1~112^2~79^2~2 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=40609093247b586ee6f8ca8f2b30c7d583c6fd25;p=linux-block.git bpf: allow bpf_fastcall for bpf_cast_to_kern_ctx and bpf_rdonly_cast do_misc_fixups() relaces bpf_cast_to_kern_ctx() and bpf_rdonly_cast() by a single instruction "r0 = r1". This follows bpf_fastcall contract. This commit allows bpf_fastcall pattern rewrite for these two functions in order to use them in bpf_fastcall selftests. Acked-by: Yonghong Song Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20240822084112.3257995-5-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov --- diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 94308cc7c503..543b8c9edac7 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -16170,6 +16170,9 @@ static u32 kfunc_fastcall_clobber_mask(struct bpf_kfunc_call_arg_meta *meta) /* Same as verifier_inlines_helper_call() but for kfuncs, see comment above */ static bool is_fastcall_kfunc_call(struct bpf_kfunc_call_arg_meta *meta) { + if (meta->btf == btf_vmlinux) + return meta->func_id == special_kfunc_list[KF_bpf_cast_to_kern_ctx] || + meta->func_id == special_kfunc_list[KF_bpf_rdonly_cast]; return false; }