From: Kees Cook <keescook@chromium.org>
To: Christian Brauner <brauner@kernel.org>
Cc: Kees Cook <keescook@chromium.org>,
Zack Rusin <zack.rusin@broadcom.com>,
Broadcom internal kernel review list
<bcm-kernel-feedback-list@broadcom.com>,
Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
Maxime Ripard <mripard@kernel.org>,
Thomas Zimmermann <tzimmermann@suse.de>,
David Airlie <airlied@gmail.com>, Daniel Vetter <daniel@ffwll.ch>,
dri-devel@lists.freedesktop.org,
Al Viro <viro@zeniv.linux.org.uk>, Jan Kara <jack@suse.cz>,
Jani Nikula <jani.nikula@linux.intel.com>,
Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
Rodrigo Vivi <rodrigo.vivi@intel.com>,
Tvrtko Ursulin <tursulin@ursulin.net>,
Andi Shyti <andi.shyti@linux.intel.com>,
Lucas De Marchi <lucas.demarchi@intel.com>,
Matt Atwood <matthew.s.atwood@intel.com>,
Matthew Auld <matthew.auld@intel.com>,
Nirmoy Das <nirmoy.das@intel.com>,
Jonathan Cavitt <jonathan.cavitt@intel.com>,
Will Deacon <will@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Boqun Feng <boqun.feng@gmail.com>,
Mark Rutland <mark.rutland@arm.com>,
Kent Overstreet <kent.overstreet@linux.dev>,
Masahiro Yamada <masahiroy@kernel.org>,
Nathan Chancellor <nathan@kernel.org>,
Nicolas Schier <nicolas@fjasle.eu>,
Andrew Morton <akpm@linux-foundation.org>,
linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
intel-gfx@lists.freedesktop.org, linux-kbuild@vger.kernel.org,
linux-hardening@vger.kernel.org
Subject: [PATCH 2/5] drm/vmwgfx: Do not directly manipulate file->f_count
Date: Thu, 2 May 2024 15:33:37 -0700 [thread overview]
Message-ID: <20240502223341.1835070-2-keescook@chromium.org> (raw)
In-Reply-To: <20240502222252.work.690-kees@kernel.org>
The correct helper for taking an f_count reference is get_file().
Now that it checks for 0 counts, use it and check results.
Signed-off-by: Kees Cook <keescook@chromium.org>
---
Cc: Zack Rusin <zack.rusin@broadcom.com>
Cc: Broadcom internal kernel review list <bcm-kernel-feedback-list@broadcom.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: David Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
---
drivers/gpu/drm/vmwgfx/ttm_object.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/vmwgfx/ttm_object.c b/drivers/gpu/drm/vmwgfx/ttm_object.c
index 6806c05e57f6..68d8ee3020b1 100644
--- a/drivers/gpu/drm/vmwgfx/ttm_object.c
+++ b/drivers/gpu/drm/vmwgfx/ttm_object.c
@@ -475,7 +475,7 @@ void ttm_object_device_release(struct ttm_object_device **p_tdev)
*/
static bool __must_check get_dma_buf_unless_doomed(struct dma_buf *dmabuf)
{
- return atomic_long_inc_not_zero(&dmabuf->file->f_count) != 0L;
+ return get_file(dmabuf->file) != NULL;
}
/**
--
2.34.1
next prev parent reply other threads:[~2024-05-02 22:33 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-02 22:33 [PATCH 0/5] fs: Do not allow get_file() to resurrect 0 f_count Kees Cook
2024-05-02 22:33 ` [PATCH 1/5] " Kees Cook
2024-05-02 22:53 ` Jann Horn
2024-05-02 23:03 ` Kees Cook
2024-05-03 9:02 ` Christian Brauner
2024-05-02 22:33 ` Kees Cook [this message]
2024-05-02 22:33 ` [PATCH 3/5] drm/i915: Do not directly manipulate file->f_count Kees Cook
2024-05-02 22:33 ` [PATCH 4/5] refcount: Introduce refcount_long_t and APIs Kees Cook
2024-05-06 8:04 ` kernel test robot
2024-05-02 22:33 ` [PATCH 5/5] fs: Convert struct file::f_count to refcount_long_t Kees Cook
2024-05-02 22:42 ` Al Viro
2024-05-02 22:52 ` Kees Cook
2024-05-02 23:12 ` Al Viro
2024-05-02 23:21 ` Kees Cook
2024-05-02 23:41 ` Al Viro
2024-05-03 0:10 ` Kees Cook
2024-05-03 0:14 ` Al Viro
2024-05-03 0:41 ` Kees Cook
2024-05-03 9:37 ` Christian Brauner
2024-05-03 10:36 ` Peter Zijlstra
2024-05-03 11:35 ` Christian Brauner
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