Patch "ARM64/ACPI: Fix BAD_MADT_GICC_ENTRY() macro implementation" has been added to the 4.9-stable tree

Patch "ARM64/ACPI: Fix BAD_MADT_GICC_ENTRY() macro implementation" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    ARM64/ACPI: Fix BAD_MADT_GICC_ENTRY() macro implementation

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     arm64-acpi-fix-bad_madt_gicc_entry-macro-implementation.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From cb7cf772d83d2d4e6995c5bb9e0fb59aea8f7080 Mon Sep 17 00:00:00 2001
From: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Date: Fri, 26 May 2017 17:40:02 +0100
Subject: ARM64/ACPI: Fix BAD_MADT_GICC_ENTRY() macro implementation

From: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

commit cb7cf772d83d2d4e6995c5bb9e0fb59aea8f7080 upstream.

The BAD_MADT_GICC_ENTRY() macro checks if a GICC MADT entry passes
muster from an ACPI specification standpoint. Current macro detects the
MADT GICC entry length through ACPI firmware version (it changed from 76
to 80 bytes in the transition from ACPI 5.1 to ACPI 6.0 specification)
but always uses (erroneously) the ACPICA (latest) struct (ie struct
acpi_madt_generic_interrupt - that is 80-bytes long) length to check if
the current GICC entry memory record exceeds the MADT table end in
memory as defined by the MADT table header itself, which may result in
false negatives depending on the ACPI firmware version and how the MADT
entries are laid out in memory (ie on ACPI 5.1 firmware MADT GICC
entries are 76 bytes long, so by adding 80 to a GICC entry start address
in memory the resulting address may well be past the actual MADT end,
triggering a false negative).

Fix the BAD_MADT_GICC_ENTRY() macro by reshuffling the condition checks
and update them to always use the firmware version specific MADT GICC
entry length in order to carry out boundary checks.

Fixes: b6cfb277378e ("ACPI / ARM64: add BAD_MADT_GICC_ENTRY() macro")
Reported-by: Julien Grall <julien.grall@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Julien Grall <julien.grall@arm.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Al Stone <ahs3@redhat.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/arm64/include/asm/acpi.h |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/arch/arm64/include/asm/acpi.h
+++ b/arch/arm64/include/asm/acpi.h
@@ -22,9 +22,9 @@
 #define ACPI_MADT_GICC_LENGTH	\
 	(acpi_gbl_FADT.header.revision < 6 ? 76 : 80)
 
-#define BAD_MADT_GICC_ENTRY(entry, end)						\
-	(!(entry) || (unsigned long)(entry) + sizeof(*(entry)) > (end) ||	\
-	 (entry)->header.length != ACPI_MADT_GICC_LENGTH)
+#define BAD_MADT_GICC_ENTRY(entry, end)					\
+	(!(entry) || (entry)->header.length != ACPI_MADT_GICC_LENGTH ||	\
+	(unsigned long)(entry) + ACPI_MADT_GICC_LENGTH > (end))
 
 /* Basic configuration for ACPI */
 #ifdef	CONFIG_ACPI


Patches currently in stable-queue which might be from lorenzo.pieralisi@arm.com are

queue-4.9/arm64-acpi-fix-bad_madt_gicc_entry-macro-implementation.patch