From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3469F1DE4EF; Sat, 12 Sep 2026 14:08:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789222107; cv=none; b=eTD4j6Hw2crOtdSIpe8teR6fzrQgj5ZDxAWkUnBCQVB9ASFytkCtYeBbtlYv9EySZKIFymkNKzibUdMch+gvlfUXEiISUVZgN5XokCukWxTAqHxka5Znnt69y8qR+zON6ZenNWZMvUDcuFr/D/IkGFHKRntlXae6XtmMDlTRVXs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789222107; c=relaxed/simple; bh=plizMQCxl94oA0vU8VfswiXtOX+GL3xGMyARfSEiGJU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DEiXiupaa3Y0rdGgmly22+LPsdAnW6ZHY1Hi40fmuzHh7yE5g1Ilea6tifYxGR510w4qRwzeWkWe+FkRl6EHUJd/4CAzgfQkJkE+abj/CFjDLqdfwT9WpeBwqwt9BezG4gn58mFHjjG7N2ZV5n6zDotH9rkuLoaIjaFix5UzvyE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=xyN7ceLS; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="xyN7ceLS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D994B1F000FF; Sat, 12 Sep 2026 14:08:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789222106; bh=uuLPaSz9KmElidUgQpMuRa5B2NAQQx6XgWbrfN5hYfQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=xyN7ceLSlZgzCQvtDVibkqJXQrDZwk0YBwYPSsp0aikRpQ+sGuGW9zeuuBUtAvSX3 ABNuu9R+h+48Fyf/Wwn1WsgljHrtKI7rQ2orhiwTjovSqbTH4g41qJirg1wf+VR+2G GJVOvjTDxedG/5XtxGyfnWt0gJQy2kOpY/AedxYU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Thadeu Lima de Souza Cascardo , Melissa Wen Subject: [PATCH 6.6 0520/1424] drm: Fix drm_crtc_commit leak if signaled when PAGE_FLIP_EVENT is used Date: Sat, 12 Sep 2026 08:49:12 +0200 Message-ID: <20260912065618.937169462@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065607.279695368@linuxfoundation.org> References: <20260912065607.279695368@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thadeu Lima de Souza Cascardo commit 4d4be202165e832d74849b4a68e289a2a377039c upstream. Commit 1c6ceeee6ebb ("drm/atomic: Fix memleak on ERESTARTSYS during non-blocking commits") fixed a very similar issue when the event was allocated by drm_atomic_helper_setup_commit() itself. However, if the event is allocated in prepare_signaling(), it will also be set to NULL in complete_signaling(), which prevents drm_crtc_commit from being put in __drm_atomic_helper_crtc_destroy_state(). Dropping the reference when the event is set to NULL at complete_signaling() fixes the leak. The leak can be reproduced by sending a signal to the thread using DRM_MODE_PAGE_FLIP_EVENT and using a sw_sync fence to cause the atomic ioctl to block at drm_atomic_helper_wait_for_fences(). It happened both with amdgpu and vkms. Fixes: 24835e442f28 ("drm: reference count event->completion") Cc: stable@vger.kernel.org Signed-off-by: Thadeu Lima de Souza Cascardo Reviewed-by: Melissa Wen Signed-off-by: Melissa Wen Link: https://patch.msgid.link/20260727-drm_crtc_atomic_commit_leak-v1-1-23d9948a9d7c@igalia.com Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/drm_atomic_uapi.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/gpu/drm/drm_atomic_uapi.c +++ b/drivers/gpu/drm/drm_atomic_uapi.c @@ -1304,6 +1304,8 @@ static void complete_signaling(struct dr * to prevent a double free in drm_atomic_state_clear. */ if (event && (event->base.fence || event->base.file_priv)) { + if (crtc_state->commit && crtc_state->commit->abort_completion) + drm_crtc_commit_put(crtc_state->commit); drm_event_cancel_free(dev, &event->base); crtc_state->event = NULL; }