iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

nfp: bpf: prepare for call support

Browse Source 
Add skeleton of verifier checks and translation handler
for call instructions.  Make sure jump target resolution
will not treat them as jumps.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit is contained in:
Jakub Kicinski 2017-12-14 21:29:17 -08:00 committed by Daniel Borkmann
parent 77a844ee65
commit 2cb230bded
2 changed files with 28 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
drivers/net/ethernet/netronome/nfp/bpf/jit.c
View File

@ -1930,6 +1930,15 @@ static int jne_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
return wrp_test_reg(nfp_prog, meta, ALU_OP_XOR, BR_BNE);
}
static int call(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
switch (meta->insn.imm) {
default:
WARN_ONCE(1, "verifier allowed unsupported function\n");
return -EOPNOTSUPP;
}
}
static int goto_out(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
wrp_br_special(nfp_prog, BR_UNC, OP_BR_GO_OUT);
@ -2002,6 +2011,7 @@ static const instr_cb_t instr_cb[256] = {
[BPF_JMP | BPF_JLE | BPF_X] = jle_reg,
[BPF_JMP | BPF_JSET | BPF_X] = jset_reg,
[BPF_JMP | BPF_JNE | BPF_X] = jne_reg,
[BPF_JMP | BPF_CALL] = call,
[BPF_JMP | BPF_EXIT] = goto_out,
};
@ -2026,6 +2036,8 @@ static int nfp_fixup_branches(struct nfp_prog *nfp_prog)
list_for_each_entry(meta, &nfp_prog->insns, l) {
if (meta->skip)
continue;
if (meta->insn.code == (BPF_JMP | BPF_CALL))
continue;
if (BPF_CLASS(meta->insn.code) != BPF_JMP)
continue;

16
drivers/net/ethernet/netronome/nfp/bpf/verifier.c
View File

@ -68,6 +68,20 @@ nfp_bpf_goto_meta(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
return meta;
}
static int
nfp_bpf_check_call(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
{
u32 func_id = meta->insn.imm;
switch (func_id) {
default:
pr_warn("unsupported function id: %d\n", func_id);
return -EOPNOTSUPP;
}
return 0;
}
static int
nfp_bpf_check_exit(struct nfp_prog *nfp_prog,
struct bpf_verifier_env *env)
@ -177,6 +191,8 @@ nfp_verify_insn(struct bpf_verifier_env *env, int insn_idx, int prev_insn_idx)
return -EINVAL;
}
if (meta->insn.code == (BPF_JMP | BPF_CALL))
return nfp_bpf_check_call(nfp_prog, meta);
if (meta->insn.code == (BPF_JMP | BPF_EXIT))
return nfp_bpf_check_exit(nfp_prog, env);