From patchwork Thu Jan 4 13:08:17 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tiezhu Yang X-Patchwork-Id: 13511102 X-Patchwork-Delegate: bpf@iogearbox.net Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 99D1522327; Thu, 4 Jan 2024 13:08:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=loongson.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=loongson.cn Received: from loongson.cn (unknown [113.200.148.30]) by gateway (Coremail) with SMTP id _____8AxnvDHrZZlSPcBAA--.7484S3; Thu, 04 Jan 2024 21:08:23 +0800 (CST) Received: from linux.localdomain (unknown [113.200.148.30]) by localhost.localdomain (Coremail) with SMTP id AQAAf8DxvofGrZZlR8wBAA--.4535S2; Thu, 04 Jan 2024 21:08:22 +0800 (CST) From: Tiezhu Yang To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: Eduard Zingerman , bpf@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH bpf-next v2] bpf: Return -ENOTSUPP if calls are not allowed in non-JITed programs Date: Thu, 4 Jan 2024 21:08:17 +0800 Message-ID: <20240104130817.1221-1-yangtiezhu@loongson.cn> X-Mailer: git-send-email 2.42.0 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: AQAAf8DxvofGrZZlR8wBAA--.4535S2 X-CM-SenderInfo: p1dqw3xlh2x3gn0dqz5rrqw2lrqou0/ X-Coremail-Antispam: 1Uk129KBj93XoWxGFW3tr1UtrW5ur1xAr48Zrc_yoW5ZFW8pa yUWr9FkF4Yq34xuw17JFs3Cayjv3yvqw47KFy5u34Fyan5CanrJr1fGryIvFyaqrWru348 Z3yxuayjgw1UGFgCm3ZEXasCq-sJn29KB7ZKAUJUUUUU529EdanIXcx71UUUUU7KY7ZEXa sCq-sGcSsGvfJ3Ic02F40EFcxC0VAKzVAqx4xG6I80ebIjqfuFe4nvWSU5nxnvy29KBjDU 0xBIdaVrnRJUUUkFb4IE77IF4wAFF20E14v26r1j6r4UM7CY07I20VC2zVCF04k26cxKx2 IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48v e4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Jr0_JF4l84ACjcxK6xIIjxv20xvEc7CjxVAFwI 0_Jr0_Gr1l84ACjcxK6I8E87Iv67AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVCY1x0267AK xVW8Jr0_Cr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l57IF6xkI12xvs2x26I8E6xACxx 1l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv 67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41l42xK82IYc2 Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s02 6x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r126r1DMIIYrxkI7VAKI48JMIIF0x vE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r1j6r4UMIIF0xvE 42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6x kF7I0E14v26r1j6r4UYxBIdaVFxhVjvjDU0xZFpf9x07UE-erUUUUU= X-Patchwork-Delegate: bpf@iogearbox.net If CONFIG_BPF_JIT_ALWAYS_ON is not set and bpf_jit_enable is 0, there exist 6 failed tests. [root@linux bpf]# echo 0 > /proc/sys/net/core/bpf_jit_enable [root@linux bpf]# echo 0 > /proc/sys/kernel/unprivileged_bpf_disabled [root@linux bpf]# ./test_verifier | grep FAIL #106/p inline simple bpf_loop call FAIL #107/p don't inline bpf_loop call, flags non-zero FAIL #108/p don't inline bpf_loop call, callback non-constant FAIL #109/p bpf_loop_inline and a dead func FAIL #110/p bpf_loop_inline stack locations for loop vars FAIL #111/p inline bpf_loop call in a big program FAIL Summary: 768 PASSED, 15 SKIPPED, 6 FAILED The test log shows that callbacks are not allowed in non-JITed programs, interpreter doesn't support them yet, thus these tests should be skipped if jit is disabled, just return -ENOTSUPP instead of -EINVAL for pseudo calls in fixup_call_args(). With this patch: [root@linux bpf]# echo 0 > /proc/sys/net/core/bpf_jit_enable [root@linux bpf]# echo 0 > /proc/sys/kernel/unprivileged_bpf_disabled [root@linux bpf]# ./test_verifier | grep FAIL Summary: 768 PASSED, 21 SKIPPED, 0 FAILED Additionally, as Eduard suggested, return -ENOTSUPP instead of -EINVAL for the other three places where "non-JITed" is used in error messages to keep consistent. Signed-off-by: Tiezhu Yang --- v2: -- rebase on the latest bpf-next tree. -- return -ENOTSUPP instead of -EINVAL for the other three places where "non-JITed" is used in error messages to keep consistent. -- update the patch subject and commit message. kernel/bpf/verifier.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index d5f4ff1eb235..99558a5186b2 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -8908,7 +8908,7 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env, goto error; if (env->subprog_cnt > 1 && !allow_tail_call_in_subprogs(env)) { verbose(env, "tail_calls are not allowed in non-JITed programs with bpf-to-bpf calls\n"); - return -EINVAL; + return -ENOTSUPP; } break; case BPF_FUNC_perf_event_read: @@ -19069,14 +19069,14 @@ static int fixup_call_args(struct bpf_verifier_env *env) #ifndef CONFIG_BPF_JIT_ALWAYS_ON if (has_kfunc_call) { verbose(env, "calling kernel functions are not allowed in non-JITed programs\n"); - return -EINVAL; + return -ENOTSUPP; } if (env->subprog_cnt > 1 && env->prog->aux->tail_call_reachable) { /* When JIT fails the progs with bpf2bpf calls and tail_calls * have to be rejected, since interpreter doesn't support them yet. */ verbose(env, "tail_calls are not allowed in non-JITed programs with bpf-to-bpf calls\n"); - return -EINVAL; + return -ENOTSUPP; } for (i = 0; i < prog->len; i++, insn++) { if (bpf_pseudo_func(insn)) { @@ -19084,7 +19084,7 @@ static int fixup_call_args(struct bpf_verifier_env *env) * have to be rejected, since interpreter doesn't support them yet. */ verbose(env, "callbacks are not allowed in non-JITed programs\n"); - return -EINVAL; + return -ENOTSUPP; } if (!bpf_pseudo_call(insn))