From nobody Sat Nov 30 10:35:03 2024 Received: from mail-pl1-f173.google.com (mail-pl1-f173.google.com [209.85.214.173]) (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 D29CF196D9D; Tue, 10 Sep 2024 14:41:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.173 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725979282; cv=none; b=PSG4od7FANea0qQ+D5pcMSskkw5z1T2tOblJeUpuacJWYYCOtPODUzfyqg+PKTZJckuYK1QyUw8jLLA+WnGkWaR/0th8WI6XBdt4B4td6j57d+zNrEfzYp3LJqOTPTa7p0PWd9Mo4KBVduQmxVwllKzZtaKo2vPE0Zte1V08q1Q= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725979282; c=relaxed/simple; bh=PpD05954nnxBVZxuYesivDXuQr5KszMF/qiXMGW+GF8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=sMHVuzmIebs/Aa8O67qh6vbIwQZBQEa4pxCdCt1YMp+G3bb/AmpCqLNceilWkpyA8fvNEH5NGiPM0sZPMHtyvflP6Liuenzv7NPWTclDZqjp4X8QY1Vw67csG8haFHrV7uUVk9jAsEpQ4d2oPUJCEZYK6VnFGkqzbx1y8m8ay84= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=EZhnnAIg; arc=none smtp.client-ip=209.85.214.173 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="EZhnnAIg" Received: by mail-pl1-f173.google.com with SMTP id d9443c01a7336-2054feabfc3so50136465ad.1; Tue, 10 Sep 2024 07:41:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1725979280; x=1726584080; 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=XAcIP6yyaAZJRPAhebVyDvt/NZWnopt98DEX8XwAkmk=; b=EZhnnAIgN3y/bFwp4vOVs7eDQA2iabFu+1F3wa41hwa6KckdDeCjIhCpqjRaUqU9X/ /TL+/hvSxLdbDK0pizViuiVpdKg/qBWK5iazwfxXm8C5Xjj6dTY/RvRhBfJOg3ycUwnO hUzL8dM0spSBUjx5s88kchYHgINsM20YGVWl+CIm5K1+pvypKo88c3m62lcPg12XYq70 3V27R6gtAUbCVcVoffkxgACQM5T/2Oxs3DHw7DSeAFZWcFl9LRC7+H+GHuu6oU5TYngv 5kQTjTAYiaCEOj7rK2ynW7hycTk2/R5md9iMpovv78Ez1drOF9/V1yG/xnG/fxUgu+5Y isuQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1725979280; x=1726584080; 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=XAcIP6yyaAZJRPAhebVyDvt/NZWnopt98DEX8XwAkmk=; b=XG+0PenK6fNjL/20W/bryzqzPBr5S24oieoIkGVYzzhG/Zo47ZuK3edXPxqB5pto+w PF9pISKSTMeIS8KZ71zhabnSNXNdrVqlq9fw6+9Am1c/6wLfxFxXq9CP2oTLFCkIJ9NR 05+6x8BZQGcz3MApcDxl+zHl5fsQjSUuxn94WRm/l8T3bEAsPI7uCE4QVoiD2pjzZrJo cV4UVSZ1tbufavDmYPSLP/pdH+ySlE2x7ym3DLPlVuzDONqoNxU+UmCb6PR17MPs51ta VruDYg4n2GDTfr+jHicdIIEbeLXVxbyk2mZHXqX+VP9jCHSboc7WWDCKlrDWYCW1xn+s DGpA== X-Forwarded-Encrypted: i=1; AJvYcCW0a+iEy9L83Cd+j9CzJCgeqt0BWNedMrFvbnTC5OoDnWlq1xE/W+mP8/uj7y53dLlupro=@vger.kernel.org, AJvYcCXQDD3Umna2PpRuD4FRjkWRdDCPk/svzC/WROT6vuUIuLUKAhdk+dC4/fDwg0MJhvhLUDOv1ba8vCT7hdSW@vger.kernel.org X-Gm-Message-State: AOJu0YwC0n3OFzDMGLTC/fhUHGnu1tVywd0mI3IRyTE6Pfau2opNljc9 bZ9bK6VObCp+f/2Ct8+dFqwIQcmQTCZE8TAjaSErXhTiffpcVjiy X-Google-Smtp-Source: AGHT+IHmvUBz7fk/UCIXIZ//0faoJOq2TX3I8JkxJznk+y/j/c6zzfsoyEBVe0TEHViH2yp9X/a0Sw== X-Received: by 2002:a17:902:c40c:b0:203:a046:c676 with SMTP id d9443c01a7336-2074c37971amr10873635ad.0.1725979279811; Tue, 10 Sep 2024 07:41:19 -0700 (PDT) Received: from localhost ([116.198.225.81]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-20710e353ecsm49775845ad.116.2024.09.10.07.41.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 10 Sep 2024 07:41:19 -0700 (PDT) From: Tao Chen To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Eduard Zingerman , Song Liu , Hou Tao , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev Cc: Tao Chen , bpf@vger.kernel.org, linux-kernel@vger.kernel.org, Jinke Han , Jiri Olsa Subject: [v3 PATCH bpf-next 1/2] bpf: Check percpu map value size first Date: Tue, 10 Sep 2024 22:41:10 +0800 Message-Id: <20240910144111.1464912-2-chen.dylane@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240910144111.1464912-1-chen.dylane@gmail.com> References: <20240910144111.1464912-1-chen.dylane@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Percpu map is often used, but the map value size limit often ignored, like issue: https://github.com/iovisor/bcc/issues/2519. Actually, percpu map value size is bound by PCPU_MIN_UNIT_SIZE, so we can check the value size whether it exceeds PCPU_MIN_UNIT_SIZE first, like percpu map of local_storage. Maybe the error message seems clearer compared with "cannot allocate memory". Signed-off-by: Tao Chen Signed-off-by: Jinke Han Acked-by: Jiri Olsa Acked-by: Andrii Nakryiko --- kernel/bpf/arraymap.c | 3 +++ kernel/bpf/hashtab.c | 3 +++ 2 files changed, 6 insertions(+) diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index a43e62e2a8bb..79660e3fca4c 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -73,6 +73,9 @@ int array_map_alloc_check(union bpf_attr *attr) /* avoid overflow on round_up(map->value_size) */ if (attr->value_size > INT_MAX) return -E2BIG; + /* percpu map value size is bound by PCPU_MIN_UNIT_SIZE */ + if (percpu && round_up(attr->value_size, 8) > PCPU_MIN_UNIT_SIZE) + return -E2BIG; =20 return 0; } diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index 45c7195b65ba..b14b87463ee0 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -462,6 +462,9 @@ static int htab_map_alloc_check(union bpf_attr *attr) * kmalloc-able later in htab_map_update_elem() */ return -E2BIG; + /* percpu map value size is bound by PCPU_MIN_UNIT_SIZE */ + if (percpu && round_up(attr->value_size, 8) > PCPU_MIN_UNIT_SIZE) + return -E2BIG; =20 return 0; } --=20 2.43.0