This is a note to let you know that I've just added the patch titled
ACPI: FPDT: properly handle invalid FPDT subtables
to the 6.5-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-fpdt-properly-handle-invalid-fpdt-subtables.patch
and it can be found in the queue-6.5 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From a83c68a3bf7c418c9a46693c63c638852b0c1f4e Mon Sep 17 00:00:00 2001
From: Vasily Khoruzhick <anarsoul@xxxxxxxxx>
Date: Wed, 27 Sep 2023 12:50:02 -0700
Subject: ACPI: FPDT: properly handle invalid FPDT subtables
From: Vasily Khoruzhick <anarsoul@xxxxxxxxx>
commit a83c68a3bf7c418c9a46693c63c638852b0c1f4e upstream.
Buggy BIOSes may have invalid FPDT subtables, e.g. on my hardware:
S3PT subtable:
7F20FE30: 53 33 50 54 24 00 00 00-00 00 00 00 00 00 18 01 *S3PT$...........*
7F20FE40: 00 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00 *................*
7F20FE50: 00 00 00 00
Here the first record has zero length.
FBPT subtable:
7F20FE50: 46 42 50 54-3C 00 00 00 46 42 50 54 *....FBPT<...FBPT*
7F20FE60: 02 00 30 02 00 00 00 00-00 00 00 00 00 00 00 00 *..0.............*
7F20FE70: 2A A6 BC 6E 0B 00 00 00-1A 44 41 70 0B 00 00 00 **..n.....DAp....*
7F20FE80: 00 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00 *................*
And here FBPT table has FBPT signature repeated instead of the first
record.
Current code will be looping indefinitely due to zero length records, so
break out of the loop if record length is zero.
While we are here, add proper handling for fpdt_process_subtable()
failures.
Fixes: d1eb86e59be0 ("ACPI: tables: introduce support for FPDT table")
Cc: All applicable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Vasily Khoruzhick <anarsoul@xxxxxxxxx>
[ rjw: Comment edit, added empty code lines ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/acpi/acpi_fpdt.c | 45 +++++++++++++++++++++++++++++++++++++--------
1 file changed, 37 insertions(+), 8 deletions(-)
--- a/drivers/acpi/acpi_fpdt.c
+++ b/drivers/acpi/acpi_fpdt.c
@@ -194,12 +194,19 @@ static int fpdt_process_subtable(u64 add
record_header = (void *)subtable_header + offset;
offset += record_header->length;
+ if (!record_header->length) {
+ pr_err(FW_BUG "Zero-length record found in FPTD.\n");
+ result = -EINVAL;
+ goto err;
+ }
+
switch (record_header->type) {
case RECORD_S3_RESUME:
if (subtable_type != SUBTABLE_S3PT) {
pr_err(FW_BUG "Invalid record %d for subtable %s\n",
record_header->type, signature);
- return -EINVAL;
+ result = -EINVAL;
+ goto err;
}
if (record_resume) {
pr_err("Duplicate resume performance record found.\n");
@@ -208,7 +215,7 @@ static int fpdt_process_subtable(u64 add
record_resume = (struct resume_performance_record *)record_header;
result = sysfs_create_group(fpdt_kobj, &resume_attr_group);
if (result)
- return result;
+ goto err;
break;
case RECORD_S3_SUSPEND:
if (subtable_type != SUBTABLE_S3PT) {
@@ -223,13 +230,14 @@ static int fpdt_process_subtable(u64 add
record_suspend = (struct suspend_performance_record *)record_header;
result = sysfs_create_group(fpdt_kobj, &suspend_attr_group);
if (result)
- return result;
+ goto err;
break;
case RECORD_BOOT:
if (subtable_type != SUBTABLE_FBPT) {
pr_err(FW_BUG "Invalid %d for subtable %s\n",
record_header->type, signature);
- return -EINVAL;
+ result = -EINVAL;
+ goto err;
}
if (record_boot) {
pr_err("Duplicate boot performance record found.\n");
@@ -238,7 +246,7 @@ static int fpdt_process_subtable(u64 add
record_boot = (struct boot_performance_record *)record_header;
result = sysfs_create_group(fpdt_kobj, &boot_attr_group);
if (result)
- return result;
+ goto err;
break;
default:
@@ -247,6 +255,18 @@ static int fpdt_process_subtable(u64 add
}
}
return 0;
+
+err:
+ if (record_boot)
+ sysfs_remove_group(fpdt_kobj, &boot_attr_group);
+
+ if (record_suspend)
+ sysfs_remove_group(fpdt_kobj, &suspend_attr_group);
+
+ if (record_resume)
+ sysfs_remove_group(fpdt_kobj, &resume_attr_group);
+
+ return result;
}
static int __init acpi_init_fpdt(void)
@@ -255,6 +275,7 @@ static int __init acpi_init_fpdt(void)
struct acpi_table_header *header;
struct fpdt_subtable_entry *subtable;
u32 offset = sizeof(*header);
+ int result;
status = acpi_get_table(ACPI_SIG_FPDT, 0, &header);
@@ -263,8 +284,8 @@ static int __init acpi_init_fpdt(void)
fpdt_kobj = kobject_create_and_add("fpdt", acpi_kobj);
if (!fpdt_kobj) {
- acpi_put_table(header);
- return -ENOMEM;
+ result = -ENOMEM;
+ goto err_nomem;
}
while (offset < header->length) {
@@ -272,8 +293,10 @@ static int __init acpi_init_fpdt(void)
switch (subtable->type) {
case SUBTABLE_FBPT:
case SUBTABLE_S3PT:
- fpdt_process_subtable(subtable->address,
+ result = fpdt_process_subtable(subtable->address,
subtable->type);
+ if (result)
+ goto err_subtable;
break;
default:
/* Other types are reserved in ACPI 6.4 spec. */
@@ -282,6 +305,12 @@ static int __init acpi_init_fpdt(void)
offset += sizeof(*subtable);
}
return 0;
+err_subtable:
+ kobject_put(fpdt_kobj);
+
+err_nomem:
+ acpi_put_table(header);
+ return result;
}
fs_initcall(acpi_init_fpdt);
Patches currently in stable-queue which might be from anarsoul@xxxxxxxxx are
queue-6.5/acpi-fpdt-properly-handle-invalid-fpdt-subtables.patch
