From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 593F5606A335 for ; Sat, 7 Nov 2026 02:20:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=VZG1LcMF Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B925F10E50C; Sat, 7 Nov 2026 02:20:35 +0000 (UTC) Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id A3C7810E505 for ; Sat, 7 Nov 2026 02:20:29 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 8AEFF43627; Sat, 7 Nov 2026 02:20:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7C4DD1F008A3; Sat, 7 Nov 2026 02:20:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794018029; bh=GQNExV2IBW/VIXiP+QKPq05xQXuih8H7xGZygNB42ds=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=VZG1LcMFLK+j+r6SEp67HSNoHe81odWNIkDi9DME3e9tBooSE5IWxcPaslSi8HqUH C84gS9G+hliw3eWpKdf25eor+MavBp1HQsBs38+02DpLYRyIDiszJSRMJcS5sFB+oq 7frnYU+TUngxm6yrZeRftEYxlfd17zIKUH2fO1U5EeEn3xQ6YddOC4s/6ruoddjOz/ QcDCSJczb1iUmHrKi95X1Pn3Kd4s4KkkXJO2V1hUkG4jHskRhrOGJTatlFUtNTpTMH iJv2SfkEsVXTSMr9TcfVoYEOLslAzIafhFltAhfZ2O4oAaSsvTmr014KeFh+Dp3ii+ m8M39LkGSGnnA== From: Danilo Krummrich To: dakr@kernel.org, aliceryhl@google.com, acourbot@nvidia.com, daniel.almeida@collabora.com, ojeda@kernel.org, boqun@kernel.org, gary@garyguo.net, bjorn3_gh@protonmail.com, lossin@kernel.org, a.hindborg@kernel.org, tmgross@umich.edu, tamird@kernel.org, work@onurozkan.dev, brauner@kernel.org, lyude@redhat.com, j@jananu.net, alvin.sun@linux.dev, deborah.brouwer@collabora.com, laura.nao@collabora.com, beata.michalska@arm.com Cc: nova-gpu@lists.linux.dev, dri-devel@lists.freedesktop.org, rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 2/7] rust: drm: gem: gate open/close callbacks with RegistrationGuard Date: Sat, 7 Nov 2026 03:03:20 +0100 Message-ID: <20261107021427.2105374-3-dakr@kernel.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107021427.2105374-1-dakr@kernel.org> References: <20261107021427.2105374-1-dakr@kernel.org> X-Archived-By: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "dri-devel" X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 Wrap the GEM object open and close callbacks with a RegistrationGuard (drm_dev_enter / drm_dev_exit) to ensure the driver callbacks only run while the parent bus device is bound. If the device has been unbound, open returns -ENODEV and close silently returns. This prevents driver code from accessing device resources after unbind and is a prerequisite for making drm::Driver::File lifetime-parameterized, since GEM callbacks receive a &drm::File that could otherwise be used to access invalidated file private data. Reviewed-by: Alice Ryhl Reviewed-by: Daniel Almeida Signed-off-by: Danilo Krummrich --- rust/kernel/drm/gem/mod.rs | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/rust/kernel/drm/gem/mod.rs b/rust/kernel/drm/gem/mod.rs index 85657a39e146..94355081edab 100644 --- a/rust/kernel/drm/gem/mod.rs +++ b/rust/kernel/drm/gem/mod.rs @@ -128,6 +128,14 @@ extern "C" fn open_callback( raw_obj: *mut bindings::drm_gem_object, raw_file: *mut bindings::drm_file, ) -> core::ffi::c_int { + // SAFETY: `raw_obj` is a valid pointer to a `struct drm_gem_object` with a valid `dev`. + let dev: &drm::Device = + unsafe { drm::Device::from_raw((*raw_obj).dev) }; + + let Some(_guard) = dev.registration_guard() else { + return ENODEV.to_errno(); + }; + // SAFETY: `open_callback` is only ever called with a valid pointer to a `struct drm_file`. let file = unsafe { DriverFile::::from_raw(raw_file) }; @@ -148,6 +156,14 @@ extern "C" fn close_callback( raw_obj: *mut bindings::drm_gem_object, raw_file: *mut bindings::drm_file, ) { + // SAFETY: `raw_obj` is a valid pointer to a `struct drm_gem_object` with a valid `dev`. + let dev: &drm::Device = + unsafe { drm::Device::from_raw((*raw_obj).dev) }; + + let Some(_guard) = dev.registration_guard() else { + return; + }; + // SAFETY: `open_callback` is only ever called with a valid pointer to a `struct drm_file`. let file = unsafe { DriverFile::::from_raw(raw_file) }; -- 2.56.0