From nobody Fri Dec 19 01:41:54 2025 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (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 191BD22F19 for ; Thu, 20 Feb 2025 01:20:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740014453; cv=none; b=LuXEg/ZsGMvKM0ZW6zqqIDyL07xJj1nChplUrLy4Eyljlde1PDJGe9+liZs0V+8TJUIRCB+zr0/QwndWgorI59NDsxII2YL6AHVh4gfFaBnlFrOps9Ues5hOn8RdltBVDoUkZeAbCg1vSp9paso80PG0n/qT0PlV73OORCPwz+o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740014453; c=relaxed/simple; bh=8BEtdyFL+la1SWhGjdvnuHQmk94dfd7pWP8oR4rmWzA=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=T5fgwqP4Xy5eysyNpQRKQjVde7i+6Uv/YFE7CdBTS87TChOZgAkLzO0YXAHNCQLPE1BzWJdD/hkU5OF2ebDC2J6nu/3Do8osdpZ/8qgag4W34yumvRqhKrn1tswScZuTTXeapqI05FdrH0jkw3fv/yr94RQFAA9OjcI8SzHVsNg= 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=tD9ic9Vy; arc=none smtp.client-ip=209.85.214.201 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="tD9ic9Vy" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-220c1f88eb4so5434975ad.2 for ; Wed, 19 Feb 2025 17:20:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1740014451; x=1740619251; 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=AVw9FAeQI7lCZwFZLEeeKDcfx7NZFxNIup/gnaKUq1Q=; b=tD9ic9VyzQSbZsr3+usJdbzn6jBeZGgu62yH2EqklfdWkTkPsRPQvU9WJ0GnUuaU/t YIJZrjSlHixsEPcaqMkZ7PdmVcy5n1aWH/H5byfayecgwZhnpU8YlLcH/IJYAlk32Cve LcaYSBdZszb4PEMuMKSPf7IcSPVQu64siQEe6uyZhwQN6aT+850cHyJfpfb4cQ9IeLBz R19/ZcEBiLje0LrbIm1s6bOTngS3AJuWVhunr9mHFCDiggzNarqt4Xx2oGuQqdavTRzp /K//8E8KmaIER3D35J5ZWAx7jsh7b2B52/Drja7uy1iB5X00d+yDYTmmsmbXgmlwkP/j LG6w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1740014451; x=1740619251; 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=AVw9FAeQI7lCZwFZLEeeKDcfx7NZFxNIup/gnaKUq1Q=; b=EvaQtWWWEUX+UFJpKEStVK5ykZazJLvE9hOaEmYNgIbaSVk/04xahAtQVRW8zYhAfu QXfsc0r2Gil9wRkuKiRMRymWfEwhsjdv83SXSNHF+B2AzJhRztKi5IsjLxoYGC8nm7Jl RsMUsYk+Xoex5QGihsURwGzgNl521VX3r/4VDV8R9ePV/34Dnu0K5X3NnMj019c3IWtS eruCdWe2cyVPOGvzcnc+jl8VoC/EijHFVRUWDSyZJXMEEv6vbjLE79BhO3t1gogDM0LF tJM3RdngDGw5I5ZkEyfHt+nJPE+dahb6ffvIC5IZ8OSQugU6sZqAm/8a3xae4vHhallJ PLsQ== X-Forwarded-Encrypted: i=1; AJvYcCV/YfNFzznFwoGGVvBeWYBlPkPHYOKrf0xcMfeA401pV2/3QVeJmXCAgGsOeREK22iGddOasbT6Zo6e0hw=@vger.kernel.org X-Gm-Message-State: AOJu0YzLIC9rPgDxKITpb683WMKHqYlT8ZgmWMrj2vmoVSkJS7QZ7nGE 0qsKLMMivCcSfI9pBgloMGxVo/FuS9hCpcIaUbhZKXM9sNzDdSTmsTGNKqgt+hfMJODvyZc77/2 tht+pywoYEA== X-Google-Smtp-Source: AGHT+IELkZhp3dnu1j1hrZyZSNzylf6/SsN58EX3cCnB9zawb1C1aTd09ns9uhXgPWFn3IcwfNEV46XMOLhkTw== X-Received: from plbbj7.prod.google.com ([2002:a17:902:8507:b0:221:7c80:aeff]) (user=yepeilin job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:41c3:b0:220:ef79:aca9 with SMTP id d9443c01a7336-221711c8dd8mr102260065ad.53.1740014451316; Wed, 19 Feb 2025 17:20:51 -0800 (PST) Date: Thu, 20 Feb 2025 01:20:41 +0000 In-Reply-To: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: X-Mailer: git-send-email 2.48.1.601.g30ceb7b040-goog Message-ID: <91e99076cf23e75e4831c75b38f8cfa84d7da34b.1740009184.git.yepeilin@google.com> Subject: [PATCH bpf-next v3 2/9] 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, Xu Kuohai , Eduard Zingerman , David Vernet , Alexei Starovoitov , 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 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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 21658bd5e6d8..63d810bbc26e 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -7615,28 +7615,12 @@ 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_ty= pe type, bool allow_trust_mismatch); =20 -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; =20 - 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) !=3D BPF_W && BPF_SIZE(insn->code) !=3D BPF_DW) { verbose(env, "invalid atomic operand size\n"); return -EINVAL; @@ -7698,12 +7682,12 @@ static int check_atomic(struct bpf_verifier_env *en= v, 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 =3D check_mem_access(env, insn_idx, insn->dst_reg, insn->off, + err =3D 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 >=3D 0) - err =3D check_mem_access(env, insn_idx, insn->dst_reg, insn->off, - BPF_SIZE(insn->code), BPF_READ, load_reg, - true, false); + err =3D 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; =20 @@ -7713,13 +7697,34 @@ static int check_atomic(struct bpf_verifier_env *en= v, int insn_idx, struct bpf_i return err; } /* Check whether we can write into the same memory. */ - err =3D check_mem_access(env, insn_idx, insn->dst_reg, insn->off, + err =3D 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; } =20 +static int check_atomic(struct bpf_verifier_env *env, struct bpf_insn *ins= n) +{ + 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 thr= ough * a helper function) make sure that it's within stack boundary and, depen= ding * on the access type and privileges, that all elements of the stack are @@ -19187,7 +19192,7 @@ static int do_check(struct bpf_verifier_env *env) enum bpf_reg_type dst_reg_type; =20 if (BPF_MODE(insn->code) =3D=3D BPF_ATOMIC) { - err =3D check_atomic(env, env->insn_idx, insn); + err =3D check_atomic(env, insn); if (err) return err; env->insn_idx++; --=20 2.48.1.601.g30ceb7b040-goog