From patchwork Mon Mar 3 05:37:19 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peilin Ye X-Patchwork-Id: 13998210 X-Patchwork-Delegate: bpf@iogearbox.net Received: from mail-ot1-f73.google.com (mail-ot1-f73.google.com [209.85.210.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A63EA1DCB24 for ; Mon, 3 Mar 2025 05:37:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740980245; cv=none; b=ZcOxwbTDUfOxMbxVMQl1X5WkMHgIaquQdrwqGE1R7ek3l5tdRdxRH2MafvcY3usro9PZ5nQpuSW0q++1DQ+kpiBhBnR2TVJcRSakdh+wJOomllW76yyoK2jyXwXtXiLIzmyssz06nOgpwF922igUmGkIfVhkZp0WRDpXtsbsx0M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740980245; c=relaxed/simple; bh=7knf85jVRu6AA2qW2iwIFp+1/VVhv5rUXtSLUlAdyq4=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=Bk49J5rneE1Ny10GLRhFPPwrYsCKAsMxg85snoDqSS3XWewpcO+YdQaGfx2RsqpKMpdKpNZ8+67MzpOtcO5JWJ934G7ZhIVl1DgkVmSm3Hytbm+7KSUvzcdHjdhglbRTcIUDck5vT/E9qFOO9JRc+Ab3aepwnZfibJ/57sPjzxo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--yepeilin.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=TLbRHSH6; arc=none smtp.client-ip=209.85.210.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--yepeilin.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="TLbRHSH6" Received: by mail-ot1-f73.google.com with SMTP id 46e09a7af769-727332732b0so964903a34.1 for ; Sun, 02 Mar 2025 21:37:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1740980242; x=1741585042; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=t+JbDsy67cUYL40rbVjYYPAZCoJAbJK+Bgpj1Q0SZXU=; b=TLbRHSH6P8a2/5iMsLgN/QvHyTWLOTg3Z+CBGaVo9KYt2LBvQYiLtF6zz7iRCk5OCR tXYWgXrw2rdEopvs/hSf9s8UBnDkKo72TLixj8BBIbzQEPqSjhqCH9ZvHbBvM/3ywYat bil7xikwlxHWNZ96jO7FHha/YRmVvnEJDpT33+yPrfvya2AMSut2Hkb9j/4pj9tU5JKw OeoWlFdGEje22X0CgicHI/IFiPHD3/5Y0qRCynM9T+JeE/od4SLF2nLCy40zFpoOi8Uy n3ES4W8eKMu31RGwA9ZJHfZ50taXiG3hVdZdcKd3R5uxm7cSIS7600dgqzfiq8qsScqT Rw7g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1740980242; x=1741585042; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=t+JbDsy67cUYL40rbVjYYPAZCoJAbJK+Bgpj1Q0SZXU=; b=i0rr0bSncJIN8Qm2tLxIpnEOrVrBiAeocHtMYcU9C5yInppk153FO+GPmFk+MK98Jr x0FyKg/+DR+wXnLajJpKD8ylwEe7S9Ue5GsjqCQd6vjHI1D1kEM0jFA58PMWdK3BNVco kcuWxinWWLXTE4qcji7q0c0NE/yws5d55hX2YCjWGci3VMdlS79MQExRlni2OkLPVdjt 4Ecd1DRcQyOm1w5hwLvoJuMtnM/5WVGXnx13Qoz9i2PMmnlgGYylIWKjlglzH7Z4YOCF pNBFxzTGwXE7s9aO+ozT0g6z5eFuyYIgjRgD3Yzw/AN/3GpQWyGE2e+g3JQNJW5zSZuH stZw== X-Gm-Message-State: AOJu0YwZK70CZM62ugVijZHbOIaFuia/a8LPomWaYwJIxcDmQ/gyUE/F QccnS7AA99XRpmy2tK4ldGaB7yM6Fb2mtqbpwajEP+PK9XfDSR1b3O27tAfi7lr7V90H28bAVlt hqhE4A6iS3qANEy/PszSybruxez4rUjWk4S94oAMGdywuI3vsC0RekBnRH5PREi2xDMzSBsqn4M mKHqtdUpe9tiu9NjBIHev4VFsEsnzPe9FC1CNKJEg= X-Google-Smtp-Source: AGHT+IFuLGBKXj1TfcM+fxYVw/tUg0+xPiDUPHUfaif0a8hS8bsHY09Qvrucsh1Gl+blURS/FrX7hRSfk4jONw== X-Received: from oaclu2.prod.google.com ([2002:a05:6871:3142:b0:2bc:6ad3:5671]) (user=yepeilin job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6870:af08:b0:29e:7603:be65 with SMTP id 586e51a60fabf-2c178337712mr6365626fac.1.1740980242647; Sun, 02 Mar 2025 21:37:22 -0800 (PST) Date: Mon, 3 Mar 2025 05:37:19 +0000 In-Reply-To: Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: X-Mailer: git-send-email 2.48.1.711.g2feabab25a-goog Message-ID: <6323ac8e73a10a1c8ee547c77ed68cf8eb6b90e1.1740978603.git.yepeilin@google.com> Subject: [PATCH bpf-next v4 02/10] bpf/verifier: Factor out check_atomic_rmw() From: Peilin Ye To: bpf@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Peilin Ye , bpf@ietf.org, Alexei Starovoitov , Xu Kuohai , Eduard Zingerman , David Vernet , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Jonathan Corbet , "Paul E. McKenney" , Puranjay Mohan , Ilya Leoshkevich , Heiko Carstens , Vasily Gorbik , Catalin Marinas , Will Deacon , Quentin Monnet , Mykola Lysenko , Shuah Khan , Ihor Solodrai , Yingchi Long , Josh Don , Barret Rhoden , Neel Natu , Benjamin Segall , linux-kernel@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Currently, check_atomic() only handles atomic read-modify-write (RMW) instructions. Since we are planning to introduce other types of atomic instructions (i.e., atomic load/store), extract the existing RMW handling logic into its own function named check_atomic_rmw(). Remove the @insn_idx parameter as it is not really necessary. Use 'env->insn_idx' instead, as in other places in verifier.c. Signed-off-by: Peilin Ye --- kernel/bpf/verifier.c | 53 +++++++++++++++++++++++-------------------- 1 file changed, 29 insertions(+), 24 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 66b19fa4be48..e3991ac72029 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -7616,28 +7616,12 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn static int save_aux_ptr_type(struct bpf_verifier_env *env, enum bpf_reg_type type, bool allow_trust_mismatch); -static int check_atomic(struct bpf_verifier_env *env, int insn_idx, struct bpf_insn *insn) +static int check_atomic_rmw(struct bpf_verifier_env *env, + struct bpf_insn *insn) { int load_reg; int err; - switch (insn->imm) { - case BPF_ADD: - case BPF_ADD | BPF_FETCH: - case BPF_AND: - case BPF_AND | BPF_FETCH: - case BPF_OR: - case BPF_OR | BPF_FETCH: - case BPF_XOR: - case BPF_XOR | BPF_FETCH: - case BPF_XCHG: - case BPF_CMPXCHG: - break; - default: - verbose(env, "BPF_ATOMIC uses invalid atomic opcode %02x\n", insn->imm); - return -EINVAL; - } - if (BPF_SIZE(insn->code) != BPF_W && BPF_SIZE(insn->code) != BPF_DW) { verbose(env, "invalid atomic operand size\n"); return -EINVAL; @@ -7699,12 +7683,12 @@ static int check_atomic(struct bpf_verifier_env *env, int insn_idx, struct bpf_i /* Check whether we can read the memory, with second call for fetch * case to simulate the register fill. */ - err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off, + err = check_mem_access(env, env->insn_idx, insn->dst_reg, insn->off, BPF_SIZE(insn->code), BPF_READ, -1, true, false); if (!err && load_reg >= 0) - err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off, - BPF_SIZE(insn->code), BPF_READ, load_reg, - true, false); + err = check_mem_access(env, env->insn_idx, insn->dst_reg, + insn->off, BPF_SIZE(insn->code), + BPF_READ, load_reg, true, false); if (err) return err; @@ -7714,13 +7698,34 @@ static int check_atomic(struct bpf_verifier_env *env, int insn_idx, struct bpf_i return err; } /* Check whether we can write into the same memory. */ - err = check_mem_access(env, insn_idx, insn->dst_reg, insn->off, + err = check_mem_access(env, env->insn_idx, insn->dst_reg, insn->off, BPF_SIZE(insn->code), BPF_WRITE, -1, true, false); if (err) return err; return 0; } +static int check_atomic(struct bpf_verifier_env *env, struct bpf_insn *insn) +{ + switch (insn->imm) { + case BPF_ADD: + case BPF_ADD | BPF_FETCH: + case BPF_AND: + case BPF_AND | BPF_FETCH: + case BPF_OR: + case BPF_OR | BPF_FETCH: + case BPF_XOR: + case BPF_XOR | BPF_FETCH: + case BPF_XCHG: + case BPF_CMPXCHG: + return check_atomic_rmw(env, insn); + default: + verbose(env, "BPF_ATOMIC uses invalid atomic opcode %02x\n", + insn->imm); + return -EINVAL; + } +} + /* When register 'regno' is used to read the stack (either directly or through * a helper function) make sure that it's within stack boundary and, depending * on the access type and privileges, that all elements of the stack are @@ -19224,7 +19229,7 @@ static int do_check(struct bpf_verifier_env *env) enum bpf_reg_type dst_reg_type; if (BPF_MODE(insn->code) == BPF_ATOMIC) { - err = check_atomic(env, env->insn_idx, insn); + err = check_atomic(env, insn); if (err) return err; env->insn_idx++;