From: Hans de Goede <hdegoede@redhat.com>
To: Mark Gross <mgross@linux.intel.com>,
Andy Shevchenko <andy@infradead.org>
Cc: Hans de Goede <hdegoede@redhat.com>,
Mario Limonciello <mario.limonciello@dell.com>,
Divya Bharathi <Divya_Bharathi@dell.com>,
Alexander Naumann <alexandernaumann@gmx.de>,
platform-driver-x86@vger.kernel.org
Subject: [PATCH v2] platform/x86: dell-wmi-sysman: Make init_bios_attributes() ACPI object parsing more robust
Date: Sun, 21 Mar 2021 13:16:07 +0100 [thread overview]
Message-ID: <20210321121607.35717-1-hdegoede@redhat.com> (raw)
Make init_bios_attributes() ACPI object parsing more robust:
1. Always check that the type of the return ACPI object is package, rather
then only checking this for instance_id == 0
2. Check that the package has the minimum amount of elements which will
be consumed by the populate_foo_data() for the attr_type
Note/TODO: The populate_foo_data() functions should also be made more
robust. The should check the type of each of the elements matches the
type which they expect and in case of populate_enum_data()
obj->package.count should be passed to it as an argument and it should
re-check this itself since it consume a variable number of elements.
Fixes: e8a60aa7404b ("platform/x86: Introduce support for Systems Management Driver over WMI for Dell Systems")
Cc: Divya Bharathi <Divya_Bharathi@dell.com>
Cc: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Changes in v2:
- Restore behavior of returning -ENODEV when the get_wmiobj_pointer() call
for instance_id == 0 returns NULL. Otherwise
/sys/class/firmware-attributes/dell-wmi-sysman will get created with an
empty attributes dir (empty except for pending_reboot and reset_bios)
---
.../x86/dell/dell-wmi-sysman/sysman.c | 32 ++++++++++++++++---
1 file changed, 28 insertions(+), 4 deletions(-)
diff --git a/drivers/platform/x86/dell/dell-wmi-sysman/sysman.c b/drivers/platform/x86/dell/dell-wmi-sysman/sysman.c
index 7410ccae650c..a90ae6ba4a73 100644
--- a/drivers/platform/x86/dell/dell-wmi-sysman/sysman.c
+++ b/drivers/platform/x86/dell/dell-wmi-sysman/sysman.c
@@ -399,6 +399,7 @@ static int init_bios_attributes(int attr_type, const char *guid)
union acpi_object *obj = NULL;
union acpi_object *elements;
struct kset *tmp_set;
+ int min_elements;
/* instance_id needs to be reset for each type GUID
* also, instance IDs are unique within GUID but not across
@@ -409,14 +410,38 @@ static int init_bios_attributes(int attr_type, const char *guid)
retval = alloc_attributes_data(attr_type);
if (retval)
return retval;
+
+ switch (attr_type) {
+ case ENUM: min_elements = 8; break;
+ case INT: min_elements = 9; break;
+ case STR: min_elements = 8; break;
+ case PO: min_elements = 4; break;
+ default:
+ pr_err("Error: Unknown attr_type: %d\n", attr_type);
+ return -EINVAL;
+ }
+
/* need to use specific instance_id and guid combination to get right data */
obj = get_wmiobj_pointer(instance_id, guid);
- if (!obj || obj->type != ACPI_TYPE_PACKAGE)
+ if (!obj)
return -ENODEV;
- elements = obj->package.elements;
mutex_lock(&wmi_priv.mutex);
- while (elements) {
+ while (obj) {
+ if (obj->type != ACPI_TYPE_PACKAGE) {
+ pr_err("Error: Expected ACPI-package type, got: %d\n", obj->type);
+ retval = -EIO;
+ goto err_attr_init;
+ }
+
+ if (obj->package.count < min_elements) {
+ pr_err("Error: ACPI-package does not have enough elements: %d < %d\n",
+ obj->package.count, min_elements);
+ goto nextobj;
+ }
+
+ elements = obj->package.elements;
+
/* sanity checking */
if (elements[ATTR_NAME].type != ACPI_TYPE_STRING) {
pr_debug("incorrect element type\n");
@@ -481,7 +506,6 @@ static int init_bios_attributes(int attr_type, const char *guid)
kfree(obj);
instance_id++;
obj = get_wmiobj_pointer(instance_id, guid);
- elements = obj ? obj->package.elements : NULL;
}
mutex_unlock(&wmi_priv.mutex);
--
2.30.2
next reply other threads:[~2021-03-21 12:18 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-21 12:16 Hans de Goede [this message]
2021-03-21 12:36 ` [PATCH v2] platform/x86: dell-wmi-sysman: Make init_bios_attributes() ACPI object parsing more robust Hans de Goede
2021-03-26 15:40 ` Ksr, Prasanth
2021-03-26 16:43 ` Hans de Goede
2021-03-29 16:00 ` Ksr, Prasanth
2021-03-30 7:53 ` Hans de Goede
2021-04-01 16:45 ` Ksr, Prasanth
2021-04-07 11:32 ` Hans de Goede
2021-04-08 1:40 ` Ksr, Prasanth
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210321121607.35717-1-hdegoede@redhat.com \
--to=hdegoede@redhat.com \
--cc=Divya_Bharathi@dell.com \
--cc=alexandernaumann@gmx.de \
--cc=andy@infradead.org \
--cc=mario.limonciello@dell.com \
--cc=mgross@linux.intel.com \
--cc=platform-driver-x86@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).