From patchwork Mon Jan 8 20:52:00 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maxim Mikityanskiy X-Patchwork-Id: 761322 Received: from mail-ed1-f53.google.com (mail-ed1-f53.google.com [209.85.208.53]) (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 4D60155E5D; Mon, 8 Jan 2024 20:52:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="jYcRyf2I" Received: by mail-ed1-f53.google.com with SMTP id 4fb4d7f45d1cf-55719cdc0e1so2546040a12.1; Mon, 08 Jan 2024 12:52:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1704747168; x=1705351968; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=Ql4Pqfjh0Jhi1BvTKprb/E446Img2B4kp0cwEWA8FYU=; b=jYcRyf2I3h5ZVaJWQjpnKMBsIhGyF1fSN5JYsiChFZwafghzLwoh4oHwHHbAFXfKnk Ahh8MVHuFYVdLc4gcg5uB+YISXKnLt8C5nmMLcUjKTm9nSpVBfWAbIJFlFRyktFKT1LQ I2e5H9XZ3Fd/msrwQdk1sGmXvoDWJ8VL+QZzCbZxRZKQaVD2v1N79RUcCIG5ZTXKciG2 qEBgTCFUODe+GQmrONOwSGotqzsITc39zs15HsIRRtiMF9pu9hxJTYWuiRnKXcN98k07 oMCx53ulbtlHywct56MxIoX6zvFKp9UGKbJN0mk3ZHruRBW1Cx3+mqfLAq5SYi+z627x T/qg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1704747168; x=1705351968; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Ql4Pqfjh0Jhi1BvTKprb/E446Img2B4kp0cwEWA8FYU=; b=V5+QaaWyRO94rgSNpUEGvbfGOXqP1QeBbzDTSO6MqNAur8qpeVDArV79d74lyo3Xze Gq2XMVo2qT7x7RHqr/quOOKbs5/ggOVxDyAAx9cQjCtpXBVVpeAMWVL75MADS3N7vSX6 gtMcb1hKj2CRyqHU5BzPOeM09KUtwlbdZkgEaFRqsJeYDxcewuN5gsAoOuyH3QHZ7R1k WD8EFmw5mfwrahWY/qNrDxgyKjFRVfjkmrQ9O2kOTFZc81b7h/b5EukaAHHTl9749GBP vqJnkZoazm6dXkBHL98GgBhWBzLhh04ykX7QYwnwMmIMcVSPgA/RT7emIxIaiMM+ckV/ R1Mw== X-Gm-Message-State: AOJu0YxmSM/7mpbqbIvWXpGu3nG49dRt8KIOk6izcITKoTfNzrv+zGDv Nog+DoJmGsyvjV9x557zoUs= X-Google-Smtp-Source: AGHT+IHm3reXS/cS+H3l5RG6G2jaSgJes2s3dXPKqT3uvgOrpu+uBPSL4cznoKTs86c9uLJ6AW11Sw== X-Received: by 2002:a50:8e53:0:b0:552:7433:23ee with SMTP id 19-20020a508e53000000b00552743323eemr3023958edx.0.1704747168526; Mon, 08 Jan 2024 12:52:48 -0800 (PST) Received: from localhost ([185.220.101.80]) by smtp.gmail.com with ESMTPSA id i4-20020a056402054400b00555e52fed52sm198492edx.91.2024.01.08.12.52.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 08 Jan 2024 12:52:48 -0800 (PST) From: Maxim Mikityanskiy To: Eduard Zingerman , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Shung-Hsi Yu Cc: John Fastabend , Martin KaFai Lau , Song Liu , Yonghong Song , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Mykola Lysenko , Shuah Khan , "David S. Miller" , Jakub Kicinski , Jesper Dangaard Brouer , bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, netdev@vger.kernel.org, Maxim Mikityanskiy Subject: [PATCH bpf-next v2 06/15] bpf: Add the assign_scalar_id_before_mov function Date: Mon, 8 Jan 2024 22:52:00 +0200 Message-ID: <20240108205209.838365-7-maxtram95@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240108205209.838365-1-maxtram95@gmail.com> References: <20240108205209.838365-1-maxtram95@gmail.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Maxim Mikityanskiy Extract the common code that generates a register ID for src_reg before MOV if needed into a new function. This function will also be used in a following commit. Signed-off-by: Maxim Mikityanskiy Acked-by: Eduard Zingerman --- kernel/bpf/verifier.c | 33 +++++++++++++++++++-------------- 1 file changed, 19 insertions(+), 14 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index bc565f445410..e3eff2becd64 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -4403,6 +4403,18 @@ static bool __is_pointer_value(bool allow_ptr_leaks, return reg->type != SCALAR_VALUE; } +static void assign_scalar_id_before_mov(struct bpf_verifier_env *env, + struct bpf_reg_state *src_reg) +{ + if (src_reg->type == SCALAR_VALUE && !src_reg->id && + !tnum_is_const(src_reg->var_off)) + /* Ensure that src_reg has a valid ID that will be copied to + * dst_reg and then will be used by find_equal_scalars() to + * propagate min/max range. + */ + src_reg->id = ++env->id_gen; +} + /* Copy src state preserving dst->parent and dst->live fields */ static void copy_register_state(struct bpf_reg_state *dst, const struct bpf_reg_state *src) { @@ -13901,20 +13913,13 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn) if (BPF_SRC(insn->code) == BPF_X) { struct bpf_reg_state *src_reg = regs + insn->src_reg; struct bpf_reg_state *dst_reg = regs + insn->dst_reg; - bool need_id = src_reg->type == SCALAR_VALUE && !src_reg->id && - !tnum_is_const(src_reg->var_off); if (BPF_CLASS(insn->code) == BPF_ALU64) { if (insn->off == 0) { /* case: R1 = R2 * copy register state to dest reg */ - if (need_id) - /* Assign src and dst registers the same ID - * that will be used by find_equal_scalars() - * to propagate min/max range. - */ - src_reg->id = ++env->id_gen; + assign_scalar_id_before_mov(env, src_reg); copy_register_state(dst_reg, src_reg); dst_reg->live |= REG_LIVE_WRITTEN; dst_reg->subreg_def = DEF_NOT_SUBREG; @@ -13929,8 +13934,8 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn) bool no_sext; no_sext = src_reg->umax_value < (1ULL << (insn->off - 1)); - if (no_sext && need_id) - src_reg->id = ++env->id_gen; + if (no_sext) + assign_scalar_id_before_mov(env, src_reg); copy_register_state(dst_reg, src_reg); if (!no_sext) dst_reg->id = 0; @@ -13952,8 +13957,8 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn) if (insn->off == 0) { bool is_src_reg_u32 = src_reg->umax_value <= U32_MAX; - if (is_src_reg_u32 && need_id) - src_reg->id = ++env->id_gen; + if (is_src_reg_u32) + assign_scalar_id_before_mov(env, src_reg); copy_register_state(dst_reg, src_reg); /* Make sure ID is cleared if src_reg is not in u32 * range otherwise dst_reg min/max could be incorrectly @@ -13967,8 +13972,8 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn) /* case: W1 = (s8, s16)W2 */ bool no_sext = src_reg->umax_value < (1ULL << (insn->off - 1)); - if (no_sext && need_id) - src_reg->id = ++env->id_gen; + if (no_sext) + assign_scalar_id_before_mov(env, src_reg); copy_register_state(dst_reg, src_reg); if (!no_sext) dst_reg->id = 0;