From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 1984CBA49 for ; Tue, 7 Mar 2023 18:43:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6D4C9C433D2; Tue, 7 Mar 2023 18:43:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678214628; bh=nZGfAIzeggdGJ6iRYCgvuBR/AzMajDhQ6CjlytbIn4M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nqAAOiFMD1yvn+NGx1C+wM9x8Dewj0LO/5IAAew3udeHFXODulSCDL0qAsw853Ed1 3xxZ/2CcGFIPrwk4tKeoQIzohwnlICZWl6M/HJ4iR+P973kgWjHAYy+XtYpwcD3za/ qPHTofjIaZREkwAuQ3e6t9164mn4AEvbYlKQpgfA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Javier Martinez Canillas , Thomas Zimmermann , =?UTF-8?q?Noralf=20Tr=C3=B8nnes?= Subject: [PATCH 6.1 883/885] drm/gud: Fix UBSAN warning Date: Tue, 7 Mar 2023 18:03:37 +0100 Message-Id: <20230307170040.152197132@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230307170001.594919529@linuxfoundation.org> References: <20230307170001.594919529@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Noralf Trønnes commit 951df98024f7272f85df5044eca7374f5b5b24ef upstream. UBSAN complains about invalid value for bool: [ 101.165172] [drm] Initialized gud 1.0.0 20200422 for 2-3.2:1.0 on minor 1 [ 101.213360] gud 2-3.2:1.0: [drm] fb1: guddrmfb frame buffer device [ 101.213426] usbcore: registered new interface driver gud [ 101.989431] ================================================================================ [ 101.989441] UBSAN: invalid-load in linux/include/linux/iosys-map.h:253:9 [ 101.989447] load of value 121 is not a valid value for type '_Bool' [ 101.989451] CPU: 1 PID: 455 Comm: kworker/1:6 Not tainted 5.18.0-rc5-gud-5.18-rc5 #3 [ 101.989456] Hardware name: Hewlett-Packard HP EliteBook 820 G1/1991, BIOS L71 Ver. 01.44 04/12/2018 [ 101.989459] Workqueue: events_long gud_flush_work [gud] [ 101.989471] Call Trace: [ 101.989474] [ 101.989479] dump_stack_lvl+0x49/0x5f [ 101.989488] dump_stack+0x10/0x12 [ 101.989493] ubsan_epilogue+0x9/0x3b [ 101.989498] __ubsan_handle_load_invalid_value.cold+0x44/0x49 [ 101.989504] dma_buf_vmap.cold+0x38/0x3d [ 101.989511] ? find_busiest_group+0x48/0x300 [ 101.989520] drm_gem_shmem_vmap+0x76/0x1b0 [drm_shmem_helper] [ 101.989528] drm_gem_shmem_object_vmap+0x9/0xb [drm_shmem_helper] [ 101.989535] drm_gem_vmap+0x26/0x60 [drm] [ 101.989594] drm_gem_fb_vmap+0x47/0x150 [drm_kms_helper] [ 101.989630] gud_prep_flush+0xc1/0x710 [gud] [ 101.989639] ? _raw_spin_lock+0x17/0x40 [ 101.989648] gud_flush_work+0x1e0/0x430 [gud] [ 101.989653] ? __switch_to+0x11d/0x470 [ 101.989664] process_one_work+0x21f/0x3f0 [ 101.989673] worker_thread+0x200/0x3e0 [ 101.989679] ? rescuer_thread+0x390/0x390 [ 101.989684] kthread+0xfd/0x130 [ 101.989690] ? kthread_complete_and_exit+0x20/0x20 [ 101.989696] ret_from_fork+0x22/0x30 [ 101.989706] [ 101.989708] ================================================================================ The source of this warning is in iosys_map_clear() called from dma_buf_vmap(). It conditionally sets values based on map->is_iomem. The iosys_map variables are allocated uninitialized on the stack leading to ->is_iomem having all kinds of values and not only 0/1. Fix this by zeroing the iosys_map variables. Fixes: 40e1a70b4aed ("drm: Add GUD USB Display driver") Cc: # v5.18+ Reviewed-by: Javier Martinez Canillas Reviewed-by: Thomas Zimmermann Signed-off-by: Noralf Trønnes Link: https://patchwork.freedesktop.org/patch/msgid/20221122-gud-shadow-plane-v2-1-435037990a83@tronnes.org Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/gud/gud_pipe.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/gud/gud_pipe.c +++ b/drivers/gpu/drm/gud/gud_pipe.c @@ -157,8 +157,8 @@ static int gud_prep_flush(struct gud_dev { struct dma_buf_attachment *import_attach = fb->obj[0]->import_attach; u8 compression = gdrm->compression; - struct iosys_map map[DRM_FORMAT_MAX_PLANES]; - struct iosys_map map_data[DRM_FORMAT_MAX_PLANES]; + struct iosys_map map[DRM_FORMAT_MAX_PLANES] = { }; + struct iosys_map map_data[DRM_FORMAT_MAX_PLANES] = { }; struct iosys_map dst; void *vaddr, *buf; size_t pitch, len;