From nobody Sat Jul 25 18:01:40 2026 Received: from cstnet.cn (smtp25.cstnet.cn [159.226.251.25]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 02D9A3CE481; Wed, 15 Jul 2026 08:33:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.25 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784104387; cv=none; b=DX7t8qr3+1MeZBkYwiE+JpBllmtFNDx7ng1MzVKseBarziwZCMl+PxslNYoBJVLaZwbi8ujTqzTnpH8cACsXLSKt+lfhgy9mTxaxth9u9Z7eDicbD10iTpUZ5pylxzLM+iQ0mssPV8Llg1+Cysm0zFsVGVj+NLDLv23eBrkWQM8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784104387; c=relaxed/simple; bh=VSzAyQH2D6kC9aNH/suxC+bk5/+5gtTn6i8cR4CiMgw=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=jTz8zozSfk3jjZMjDjITos5dCoXvGC9k0RUH35dog3dl3uDIxo+g58f4fEhTG8xY7fcxWT1lKzSGulq6/6cu8Uloh4FrwmVFMXiW5LiuejHPLY6G5sUoWaPkr9k9/SX+ekGrK9u1pUQw44Kwa1kpJ6WSD5xZrzzJbB10r/mVIMk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.25 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from localhost.localdomain (unknown [111.196.245.140]) by APP-05 (Coremail) with SMTP id zQCowAD3bfG1RVdqmTlHGA--.32047S2; Wed, 15 Jul 2026 16:32:54 +0800 (CST) From: Pengpeng Hou To: "Rafael J. Wysocki" , Len Brown Cc: Pengpeng Hou , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, Yinghai Lu Subject: [PATCH] ACPI: validate MADT IOAPIC entry bounds Date: Wed, 15 Jul 2026 16:32:53 +0800 Message-ID: <20260715083253.22831-1-pengpeng@iscas.ac.cn> X-Mailer: git-send-email 2.50.1 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 X-CM-TRANSID: zQCowAD3bfG1RVdqmTlHGA--.32047S2 X-Coremail-Antispam: 1UD129KBjvJXoWxuryrWryxAFW3AF4kAryUGFg_yoW5ZryUpF WUKa4rKFW8KF47Xw4fAr45XrW5u3yxuFy7XFZ7G3sYkanxXFyrXFZ5K342qry3AFWvga17 Za4rtas8Ca1xArJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUkl14x267AKxVWUJVW8JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26ryj6F1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4j 6F4UM28EF7xvwVC2z280aVAFwI0_Cr1j6rxdM28EF7xvwVC2z280aVCY1x0267AKxVW0oV Cq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0 I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r 4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwCY1x0262kKe7AKxVWU AVWUtwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14 v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_JF0_Jw1lIxkG c2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI 0_Jr0_Gr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4U MIIF0xvEx4A2jsIEc7CjxVAFwI0_Jr0_GrUvcSsGvfC2KfnxnUUI43ZEXa7VUjuHq7UUUU U== X-CM-SenderInfo: pshqw1xhqjqxpvfd2hldfou0/ Content-Type: text/plain; charset="utf-8" The IOAPIC hotplug lookup parses both MADT and _MAT records directly. The MADT walk previously used a subtable's declared length to advance the cursor after only locating a generic header. The _MAT path likewise passed a generic header to the IOAPIC helper. Validate that a current record has a complete generic header, that its declared length is contained in the available record range, and that a typed IOAPIC record contains the full fixed IOAPIC body before reading its fields. Use the same relation for both MADT and _MAT provider paths. Fixes: ecf5636dcd59 ("ACPI: Add interfaces to parse IOAPIC ID for IOAPIC ho= tplug") Signed-off-by: Pengpeng Hou --- drivers/acpi/processor_core.c | 31 +++++++++++++++++++++++++------ 1 file changed, 25 insertions(+), 6 deletions(-) diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c index a4498357bd16..3bf076c150fa 100644 --- a/drivers/acpi/processor_core.c +++ b/drivers/acpi/processor_core.c @@ -336,11 +336,26 @@ int acpi_get_cpuid(acpi_handle handle, int type, u32 = acpi_id) EXPORT_SYMBOL_GPL(acpi_get_cpuid); =20 #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC -static int get_ioapic_id(struct acpi_subtable_header *entry, u32 gsi_base, +static bool madt_entry_is_valid(struct acpi_subtable_header *entry, + unsigned long end) +{ + unsigned long start =3D (unsigned long)entry; + + if (start >=3D end || end - start < sizeof(*entry)) + return false; + + return entry->length >=3D sizeof(*entry) && entry->length <=3D end - star= t; +} + +static int get_ioapic_id(struct acpi_subtable_header *entry, + const unsigned long end, u32 gsi_base, u64 *phys_addr, int *ioapic_id) { struct acpi_madt_io_apic *ioapic =3D (struct acpi_madt_io_apic *)entry; =20 + if (!madt_entry_is_valid(entry, end) || BAD_MADT_ENTRY(ioapic, end)) + return 0; + if (ioapic->global_irq_base !=3D gsi_base) return 0; =20 @@ -361,17 +376,19 @@ static int parse_madt_ioapic_entry(u32 gsi_base, u64 = *phys_addr) return apic_id; =20 entry =3D (unsigned long)madt; + if (madt->header.length < sizeof(*madt)) + return apic_id; madt_end =3D entry + madt->header.length; =20 /* Parse all entries looking for a match. */ entry +=3D sizeof(struct acpi_table_madt); - while (entry + sizeof(struct acpi_subtable_header) < madt_end) { + while (madt_entry_is_valid((struct acpi_subtable_header *)entry, + madt_end)) { hdr =3D (struct acpi_subtable_header *)entry; if (hdr->type =3D=3D ACPI_MADT_TYPE_IO_APIC && - get_ioapic_id(hdr, gsi_base, phys_addr, &apic_id)) + get_ioapic_id(hdr, madt_end, gsi_base, phys_addr, &apic_id)) break; - else - entry +=3D hdr->length; + entry +=3D hdr->length; } =20 return apic_id; @@ -398,7 +415,9 @@ static int parse_mat_ioapic_entry(acpi_handle handle, u= 32 gsi_base, =20 header =3D (struct acpi_subtable_header *)obj->buffer.pointer; if (header->type =3D=3D ACPI_MADT_TYPE_IO_APIC) - get_ioapic_id(header, gsi_base, phys_addr, &apic_id); + get_ioapic_id(header, + (unsigned long)header + obj->buffer.length, + gsi_base, phys_addr, &apic_id); =20 exit: kfree(buffer.pointer); --=20 2.43.0