[SRU,Trusty,1/1] x86/acpi: Prevent out of bound access caused by broken ACPI tables

Message ID 20180710172825.20738-2-kleber.souza@canonical.com
State New
Headers show
Series
  • Fix for CVE-2017-11473
Related show

Commit Message

Kleber Souza July 10, 2018, 5:28 p.m.
From: Seunghun Han <kkamagui@gmail.com>

The bus_irq argument of mp_override_legacy_irq() is used as the index into
the isa_irq_to_gsi[] array. The bus_irq argument originates from
ACPI_MADT_TYPE_IO_APIC and ACPI_MADT_TYPE_INTERRUPT items in the ACPI
tables, but is nowhere sanity checked.

That allows broken or malicious ACPI tables to overwrite memory, which
might cause malfunction, panic or arbitrary code execution.

Add a sanity check and emit a warning when that triggers.

[ tglx: Added warning and rewrote changelog ]

Signed-off-by: Seunghun Han <kkamagui@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: security@kernel.org
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

CVE-2017-11473
(cherry picked from commit dad5ab0db8deac535d03e3fe3d8f2892173fa6a4)
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
---
 arch/x86/kernel/acpi/boot.c | 8 ++++++++
 1 file changed, 8 insertions(+)

Comments

Colin King July 10, 2018, 5:34 p.m. | #1
On 10/07/18 18:28, Kleber Sacilotto de Souza wrote:
> From: Seunghun Han <kkamagui@gmail.com>
> 
> The bus_irq argument of mp_override_legacy_irq() is used as the index into
> the isa_irq_to_gsi[] array. The bus_irq argument originates from
> ACPI_MADT_TYPE_IO_APIC and ACPI_MADT_TYPE_INTERRUPT items in the ACPI
> tables, but is nowhere sanity checked.
> 
> That allows broken or malicious ACPI tables to overwrite memory, which
> might cause malfunction, panic or arbitrary code execution.
> 
> Add a sanity check and emit a warning when that triggers.
> 
> [ tglx: Added warning and rewrote changelog ]
> 
> Signed-off-by: Seunghun Han <kkamagui@gmail.com>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: security@kernel.org
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Cc: stable@vger.kernel.org
> Signed-off-by: Ingo Molnar <mingo@kernel.org>
> 
> CVE-2017-11473
> (cherry picked from commit dad5ab0db8deac535d03e3fe3d8f2892173fa6a4)
> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
> ---
>  arch/x86/kernel/acpi/boot.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
> index 6c0b43bd024b..2c3cd05ba747 100644
> --- a/arch/x86/kernel/acpi/boot.c
> +++ b/arch/x86/kernel/acpi/boot.c
> @@ -918,6 +918,14 @@ void __init mp_override_legacy_irq(u8 bus_irq, u8 polarity, u8 trigger, u32 gsi)
>  	int pin;
>  	struct mpc_intsrc mp_irq;
>  
> +	/*
> +	 * Check bus_irq boundary.
> +	 */
> +	if (bus_irq >= NR_IRQS_LEGACY) {
> +		pr_warn("Invalid bus_irq %u for legacy override\n", bus_irq);
> +		return;
> +	}
> +
>  	/*
>  	 * Convert 'gsi' to 'ioapic.pin'.
>  	 */
> 

Eeek, can't believe there was no check on that before. Looks good,

Acked-by: Colin Ian King <colin.king@canonical.com>
Stefan Bader July 19, 2018, 12:21 p.m. | #2
On 10.07.2018 19:28, Kleber Sacilotto de Souza wrote:
> From: Seunghun Han <kkamagui@gmail.com>
> 
> The bus_irq argument of mp_override_legacy_irq() is used as the index into
> the isa_irq_to_gsi[] array. The bus_irq argument originates from
> ACPI_MADT_TYPE_IO_APIC and ACPI_MADT_TYPE_INTERRUPT items in the ACPI
> tables, but is nowhere sanity checked.
> 
> That allows broken or malicious ACPI tables to overwrite memory, which
> might cause malfunction, panic or arbitrary code execution.
> 
> Add a sanity check and emit a warning when that triggers.
> 
> [ tglx: Added warning and rewrote changelog ]
> 
> Signed-off-by: Seunghun Han <kkamagui@gmail.com>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: security@kernel.org
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Cc: stable@vger.kernel.org
> Signed-off-by: Ingo Molnar <mingo@kernel.org>
> 
> CVE-2017-11473
> (cherry picked from commit dad5ab0db8deac535d03e3fe3d8f2892173fa6a4)
> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
> ---
>  arch/x86/kernel/acpi/boot.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
> index 6c0b43bd024b..2c3cd05ba747 100644
> --- a/arch/x86/kernel/acpi/boot.c
> +++ b/arch/x86/kernel/acpi/boot.c
> @@ -918,6 +918,14 @@ void __init mp_override_legacy_irq(u8 bus_irq, u8 polarity, u8 trigger, u32 gsi)
>  	int pin;
>  	struct mpc_intsrc mp_irq;
>  
> +	/*
> +	 * Check bus_irq boundary.
> +	 */
> +	if (bus_irq >= NR_IRQS_LEGACY) {
> +		pr_warn("Invalid bus_irq %u for legacy override\n", bus_irq);
> +		return;
> +	}
> +
>  	/*
>  	 * Convert 'gsi' to 'ioapic.pin'.
>  	 */
>
Juerg Haefliger July 23, 2018, 12:15 p.m. | #3
Applied to Trusty master-next.

...Juerg

On 07/10/2018 07:28 PM, Kleber Sacilotto de Souza wrote:
> From: Seunghun Han <kkamagui@gmail.com>
> 
> The bus_irq argument of mp_override_legacy_irq() is used as the index into
> the isa_irq_to_gsi[] array. The bus_irq argument originates from
> ACPI_MADT_TYPE_IO_APIC and ACPI_MADT_TYPE_INTERRUPT items in the ACPI
> tables, but is nowhere sanity checked.
> 
> That allows broken or malicious ACPI tables to overwrite memory, which
> might cause malfunction, panic or arbitrary code execution.
> 
> Add a sanity check and emit a warning when that triggers.
> 
> [ tglx: Added warning and rewrote changelog ]
> 
> Signed-off-by: Seunghun Han <kkamagui@gmail.com>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: security@kernel.org
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Cc: stable@vger.kernel.org
> Signed-off-by: Ingo Molnar <mingo@kernel.org>
> 
> CVE-2017-11473
> (cherry picked from commit dad5ab0db8deac535d03e3fe3d8f2892173fa6a4)
> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
> ---
>  arch/x86/kernel/acpi/boot.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
> index 6c0b43bd024b..2c3cd05ba747 100644
> --- a/arch/x86/kernel/acpi/boot.c
> +++ b/arch/x86/kernel/acpi/boot.c
> @@ -918,6 +918,14 @@ void __init mp_override_legacy_irq(u8 bus_irq, u8 polarity, u8 trigger, u32 gsi)
>  	int pin;
>  	struct mpc_intsrc mp_irq;
>  
> +	/*
> +	 * Check bus_irq boundary.
> +	 */
> +	if (bus_irq >= NR_IRQS_LEGACY) {
> +		pr_warn("Invalid bus_irq %u for legacy override\n", bus_irq);
> +		return;
> +	}
> +
>  	/*
>  	 * Convert 'gsi' to 'ioapic.pin'.
>  	 */
>

Patch

diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 6c0b43bd024b..2c3cd05ba747 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -918,6 +918,14 @@  void __init mp_override_legacy_irq(u8 bus_irq, u8 polarity, u8 trigger, u32 gsi)
 	int pin;
 	struct mpc_intsrc mp_irq;
 
+	/*
+	 * Check bus_irq boundary.
+	 */
+	if (bus_irq >= NR_IRQS_LEGACY) {
+		pr_warn("Invalid bus_irq %u for legacy override\n", bus_irq);
+		return;
+	}
+
 	/*
 	 * Convert 'gsi' to 'ioapic.pin'.
 	 */