linux-kernel - [PATCH v2] iommu/amd: Fix get_acpihid_device

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20200511103229.v2.1.I6f1b6f973ee6c8af1348611370c73a0ec0ea53f1@changeid>
Date:   Mon, 11 May 2020 10:33:36 -0600
From:   Raul E Rangel <rrangel@...omium.org>
To:     Joerg Roedel <jroedel@...e.de>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        iommu@...ts.linux-foundation.org, linux-acpi@...r.kernel.org
Cc:     evgreen@...omium.org, dianders@...omium.org,
        Daniel Kurtz <djkurtz@...omium.org>,
        Adrian Hunter <adrian.hunter@...el.com>,
        Ulf Hansson <ulf.hansson@...aro.org>,
        Raul E Rangel <rrangel@...omium.org>,
        Andy Shevchenko <andy.shevchenko@...il.com>,
        Jerry Snitselaar <jsnitsel@...hat.com>,
        Joerg Roedel <joro@...tes.org>,
        Mika Westerberg <mika.westerberg@...ux.intel.com>,
        "Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
        linux-kernel@...r.kernel.org
Subject: [PATCH v2] iommu/amd: Fix get_acpihid_device_id()

acpi_dev_hid_uid_match() expects a null pointer for UID if it doesn't
exist. The acpihid_map_entry contains a char buffer for holding the
UID. If no UID was provided in the IVRS table, this buffer will be
zeroed. If we pass in a null string, acpi_dev_hid_uid_match() will
return false because it will try and match an empty string to the ACPI
UID of the device.

Fixes: ae5e6c6439c3 ("iommu/amd: Switch to use acpi_dev_hid_uid_match()")
Suggested-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Signed-off-by: Raul E Rangel <rrangel@...omium.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@...il.com>
---

Changes in v2:
- Added Suggested by
- Fixed commit description
- Decided to keep `p->uid[0]` instead of `*p->uid` since the data member is an array instead of a pointer.
- Used clang-format

 drivers/iommu/amd_iommu.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 20cce366e951..06f603366cb1 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -125,7 +125,8 @@ static inline int get_acpihid_device_id(struct device *dev,
 		return -ENODEV;
 
 	list_for_each_entry(p, &acpihid_map, list) {
-		if (acpi_dev_hid_uid_match(adev, p->hid, p->uid)) {
+		if (acpi_dev_hid_uid_match(adev, p->hid,
+					   p->uid[0] ? p->uid : NULL)) {
 			if (entry)
 				*entry = p;
 			return p->devid;
-- 
2.26.2.645.ge9eca65c58-goog