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From:   Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
To:     maarten.lankhorst@linux.intel.com, mripard@kernel.org,
        tzimmermann@suse.de, airlied@linux.ie, daniel@ffwll.ch
Cc:     Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        skhan@linuxfoundation.org, gregkh@linuxfoundation.org,
        linux-kernel-mentees@lists.linuxfoundation.org,
        emil.l.velikov@gmail.com
Subject: [PATCH v2 0/2] drm: Address potential UAF bugs with drm_master ptrs
Date:   Tue, 15 Jun 2021 10:36:43 +0800
Message-Id: <20210615023645.6535-1-desmondcheongzx@gmail.com>
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This patch series addresses potential use-after-free errors when dereferencing pointers to struct drm_master. These were identified after one such bug was caught by Syzbot in drm_getunique():
https://syzkaller.appspot.com/bug?id=148d2f1dfac64af52ffd27b661981a540724f803

The series is broken up into two patches:

1. Implement a locked version of drm_is_current_master() function that's used within drm_auth.c

2. Identify areas in drm_lease.c where pointers to struct drm_master are dereferenced, and ensure that the master pointers are protected by a mutex


Change in v2:
- Patch 2: Move the lock and assignment before the DRM_DEBUG_LEASE in drm_mode_get_lease_ioctl, as suggested by Emil Velikov

Desmond Cheong Zhi Xi (2):
  drm: Add a locked version of drm_is_current_master
  drm: Protect drm_master pointers in drm_lease.c

 drivers/gpu/drm/drm_auth.c  | 23 ++++++++++++---
 drivers/gpu/drm/drm_lease.c | 58 +++++++++++++++++++++++++++----------
 2 files changed, 62 insertions(+), 19 deletions(-)

-- 
2.25.1