This is a note to let you know that I've just added the patch titled
ACPI / sysfs: fix acpi_get_table() leak / acpi-sysfs denial of service
to the 4.11-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:
acpi-sysfs-fix-acpi_get_table-leak-acpi-sysfs-denial-of-service.patch
and it can be found in the queue-4.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 0de0e198bc7191a0e46cf71f66fec4d07ca91396 Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams@xxxxxxxxx>
Date: Tue, 25 Apr 2017 12:58:31 -0700
Subject: ACPI / sysfs: fix acpi_get_table() leak / acpi-sysfs denial of service
From: Dan Williams <dan.j.williams@xxxxxxxxx>
commit 0de0e198bc7191a0e46cf71f66fec4d07ca91396 upstream.
Reading an ACPI table through the /sys/firmware/acpi/tables interface
more than 65,536 times leads to the following log message:
ACPI Error: Table ffff88033595eaa8, Validation count is zero after increment
(20170119/tbutils-423)
...and the table being unavailable until the next reboot. Add the
missing acpi_put_table() so the table ->validation_count is decremented
after each read.
Reported-by: Anush Seetharaman <anush.seetharaman@xxxxxxxxx>
Fixes: 174cc7187e6f "ACPICA: Tables: Back port acpi_get_table_with_size() ..."
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/acpi/sysfs.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
--- a/drivers/acpi/sysfs.c
+++ b/drivers/acpi/sysfs.c
@@ -333,14 +333,17 @@ static ssize_t acpi_table_show(struct fi
container_of(bin_attr, struct acpi_table_attr, attr);
struct acpi_table_header *table_header = NULL;
acpi_status status;
+ ssize_t rc;
status = acpi_get_table(table_attr->name, table_attr->instance,
&table_header);
if (ACPI_FAILURE(status))
return -ENODEV;
- return memory_read_from_buffer(buf, count, &offset,
- table_header, table_header->length);
+ rc = memory_read_from_buffer(buf, count, &offset, table_header,
+ table_header->length);
+ acpi_put_table(table_header);
+ return rc;
}
static int acpi_table_attr_init(struct kobject *tables_obj,
Patches currently in stable-queue which might be from dan.j.williams@xxxxxxxxx are
queue-4.11/acpica-tables-fix-regression-introduced-by-a-too-early-mechanism-enabling.patch
queue-4.11/acpi-sysfs-fix-acpi_get_table-leak-acpi-sysfs-denial-of-service.patch