From: "Noralf Trønnes" <noralf@tronnes.org>
To: Thomas Zimmermann <tzimmermann@suse.de>,
stable@vger.kernel.org, Dave Airlie <airlied@redhat.com>,
dri-devel@lists.freedesktop.org,
Hans de Goede <hdegoede@redhat.com>,
Noralf Trønnes <noralf@tronnes.org>,
Maxime Ripard <mripard@kernel.org>,
Javier Martinez Canillas <javierm@redhat.com>
Subject: [PATCH 2/6] drm/gud: Fix UBSAN warning
Date: Tue, 22 Nov 2022 21:58:40 +0100 [thread overview]
Message-ID: <20221122-gud-shadow-plane-v1-2-9de3afa3383e@tronnes.org> (raw)
In-Reply-To: <20221122-gud-shadow-plane-v1-0-9de3afa3383e@tronnes.org>
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 /home/pi/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] <TASK>
[ 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] </TASK>
[ 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: <stable@vger.kernel.org> # v5.18+
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
---
drivers/gpu/drm/gud/gud_pipe.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/gud/gud_pipe.c b/drivers/gpu/drm/gud/gud_pipe.c
index 7c6dc2bcd14a..61f4abaf1811 100644
--- 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_device *gdrm, struct drm_framebuffer *fb,
{
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;
--
b4 0.10.1
next prev parent reply other threads:[~2022-11-22 20:58 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-22 20:58 [PATCH 0/6] drm/gud: Use the shadow plane helper Noralf Trønnes
2022-11-22 20:58 ` [PATCH 1/6] drm/gem: shadow_fb_access: Prepare imported buffers for CPU access Noralf Trønnes
2022-11-22 20:58 ` Noralf Trønnes [this message]
2022-11-22 20:58 ` [PATCH 3/6] drm/gud: Don't retry a failed framebuffer flush Noralf Trønnes
2022-11-22 20:58 ` [PATCH 4/6] drm/gud: Split up gud_flush_work() Noralf Trønnes
2022-11-22 20:58 ` [PATCH 5/6] drm/gud: Prepare buffer for CPU access in gud_flush_work() Noralf Trønnes
2022-11-22 20:58 ` [PATCH 6/6] drm/gud: Use the shadow plane helper Noralf Trønnes
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20221122-gud-shadow-plane-v1-2-9de3afa3383e@tronnes.org \
--to=noralf@tronnes.org \
--cc=airlied@redhat.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=hdegoede@redhat.com \
--cc=javierm@redhat.com \
--cc=mripard@kernel.org \
--cc=stable@vger.kernel.org \
--cc=tzimmermann@suse.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).