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 8902853B5FD; Wed, 9 Sep 2026 14:32:24 +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=1788964345; cv=none; b=K2NqAWkWV/TaPCZJ93J+aoe1X+IAIZr9wx4tqqWwhaxkYjlE2iaYTwIiMzxvOGzQ8Tk2agLxdKsnHGqqZhwesNBcB+5SsxN8WpRMtESAdrswZHl5iAhdeM46neua+lR6sZZH8i6wGZDc0szHAccnUyP0hZ98fStr3kKc3g4GYpM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788964345; c=relaxed/simple; bh=ftpTJgcqj3AMSoFPEHZim+lYqMgu3ItmXxcm2csViCY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=fkubOKvTcKbIEtbFePpIJG3Iq2AWltDJEFiiK3X57xRGCSsJKHKscJlfu4q/Ft6WR258rOlq89roJ03qsJTR1ghIqW/i/sNCD/+amdgFYN+7f5XNiSj00tRZHb5W0tbfYtUo3E/9bE30+83Hb0YgQpxG5AFbHdcl4JevOSKSBwI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=nUmtex1e; 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="nUmtex1e" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DFE0C1F00A3A; Wed, 9 Sep 2026 14:32:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788964344; bh=WYl5h1fm0fRGWXuw7qQk+4vcFnSEeyAX240rMKfzj/s=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=nUmtex1e6UAyaZuaK2zn5hRvPEnT6lg/oRZIXhGihDhrugldUSetxs0uS9XbKBRIq c2RQkN1EnzXzyFey4VGa8vulsPNJx3fgbGZ520/CwcQsxAMMvYorlGpHjTkaBpWWB+ SYjl/GjzsnMIjjel1r6Wgn7KIF0VbWBmfmNyAVII= 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 6.18 390/583] drm: Fix drm_crtc_commit leak if signaled when PAGE_FLIP_EVENT is used Date: Wed, 9 Sep 2026 15:41:15 +0200 Message-ID: <20260909134251.498060977@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260909134237.773280130@linuxfoundation.org> References: <20260909134237.773280130@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 6.18-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 @@ -1346,6 +1346,8 @@ 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; }