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| author |   Jiong Wang <jiong.wang@netronome.com> | 2019-04-12 22:59:37 +0100 |
|---|---|---|
| committer |   Alexei Starovoitov <ast@kernel.org> | 2019-04-12 17:06:33 -0700 |
| commit | c342dc109aa5a4f0bb36335cb441aaafc98b98ef (patch) | |
| tree | e9a038688270daccc0271ba1bc93b7e745863037 /kernel | |
| parent | bpf: factor out reg and stack slot propagation into "propagate_liveness_reg" (diff) | |
| download | linux-dev-c342dc109aa5a4f0bb36335cb441aaafc98b98ef.tar.xz linux-dev-c342dc109aa5a4f0bb36335cb441aaafc98b98ef.zip | |
bpf: refactor "check_reg_arg" to eliminate code redundancy
There are a few "regs[regno]" here are there across "check_reg_arg", this
patch factor it out into a simple "reg" pointer. The intention is to
simplify code indentation and make the later patches in this set look
cleaner.
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/verifier.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 3fdb301c4f8c..c7220153c5b1 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -1177,30 +1177,32 @@ static int check_reg_arg(struct bpf_verifier_env *env, u32 regno, { struct bpf_verifier_state *vstate = env->cur_state; struct bpf_func_state *state = vstate->frame[vstate->curframe]; - struct bpf_reg_state *regs = state->regs; + struct bpf_reg_state *reg, *regs = state->regs; if (regno >= MAX_BPF_REG) { verbose(env, "R%d is invalid\n", regno); return -EINVAL; } + reg = ®s[regno]; if (t == SRC_OP) { /* check whether register used as source operand can be read */ - if (regs[regno].type == NOT_INIT) { + if (reg->type == NOT_INIT) { verbose(env, "R%d !read_ok\n", regno); return -EACCES; } /* We don't need to worry about FP liveness because it's read-only */ - if (regno != BPF_REG_FP) - return mark_reg_read(env, ®s[regno], - regs[regno].parent); + if (regno == BPF_REG_FP) + return 0; + + return mark_reg_read(env, reg, reg->parent); } else { /* check whether register used as dest operand can be written to */ if (regno == BPF_REG_FP) { verbose(env, "frame pointer is read only\n"); return -EACCES; } - regs[regno].live |= REG_LIVE_WRITTEN; + reg->live |= REG_LIVE_WRITTEN; if (t == DST_OP) mark_reg_unknown(env, regs, regno); } |