From 9af27da6313c8f8c6a26c7ea3fe23d6b9664a3a8 Mon Sep 17 00:00:00 2001 From: Kumar Kartikeya Dwivedi Date: Wed, 13 Sep 2023 01:31:58 +0200 Subject: bpf: Use bpf_is_subprog to check for subprogs We would like to know whether a bpf_prog corresponds to the main prog or one of the subprogs. The current JIT implementations simply check this using the func_idx in bpf_prog->aux->func_idx. When the index is 0, it belongs to the main program, otherwise it corresponds to some subprogram. This will also be necessary to halt exception propagation while walking the stack when an exception is thrown, so we add a simple helper function to check this, named bpf_is_subprog, and convert existing JIT implementations to also make use of it. Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20230912233214.1518551-2-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- arch/x86/net/bpf_jit_comp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/net/bpf_jit_comp.c') diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index 2846c21d75bf..a0d03503b3cb 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -1049,7 +1049,7 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, u8 *rw_image emit_prologue(&prog, bpf_prog->aux->stack_depth, bpf_prog_was_classic(bpf_prog), tail_call_reachable, - bpf_prog->aux->func_idx != 0); + bpf_is_subprog(bpf_prog)); push_callee_regs(&prog, callee_regs_used); ilen = prog - temp; -- cgit