* [PATCH] drm/virtio: fix NULL pointer dereference in virtio_gpu_conn_get_modes
@ 2022-03-22 8:18 Liu Zixian
2022-03-24 19:54 ` Chia-I Wu
0 siblings, 1 reply; 6+ messages in thread
From: Liu Zixian @ 2022-03-22 8:18 UTC (permalink / raw)
To: dri-devel, virtualization; +Cc: linfeilong, liuzixian4
drm_cvt_mode may return NULL and we should check it.
This bug is found by syzkaller:
FAULT_INJECTION stacktrace:
[ 168.567394] FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 1
[ 168.567403] CPU: 1 PID: 6425 Comm: syz Kdump: loaded Not tainted 4.19.90-vhulk2201.1.0.h1035.kasan.eulerosv2r10.aarch64 #1
[ 168.567406] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
[ 168.567408] Call trace:
[ 168.567414] dump_backtrace+0x0/0x310
[ 168.567418] show_stack+0x28/0x38
[ 168.567423] dump_stack+0xec/0x15c
[ 168.567427] should_fail+0x3ac/0x3d0
[ 168.567437] __should_failslab+0xb8/0x120
[ 168.567441] should_failslab+0x28/0xc0
[ 168.567445] kmem_cache_alloc_trace+0x50/0x640
[ 168.567454] drm_mode_create+0x40/0x90
[ 168.567458] drm_cvt_mode+0x48/0xc78
[ 168.567477] virtio_gpu_conn_get_modes+0xa8/0x140 [virtio_gpu]
[ 168.567485] drm_helper_probe_single_connector_modes+0x3a4/0xd80
[ 168.567492] drm_mode_getconnector+0x2e0/0xa70
[ 168.567496] drm_ioctl_kernel+0x11c/0x1d8
[ 168.567514] drm_ioctl+0x558/0x6d0
[ 168.567522] do_vfs_ioctl+0x160/0xf30
[ 168.567525] ksys_ioctl+0x98/0xd8
[ 168.567530] __arm64_sys_ioctl+0x50/0xc8
[ 168.567536] el0_svc_common+0xc8/0x320
[ 168.567540] el0_svc_handler+0xf8/0x160
[ 168.567544] el0_svc+0x10/0x218
KASAN stacktrace:
[ 168.567561] BUG: KASAN: null-ptr-deref in virtio_gpu_conn_get_modes+0xb4/0x140 [virtio_gpu]
[ 168.567565] Read of size 4 at addr 0000000000000054 by task syz/6425
[ 168.567566]
[ 168.567571] CPU: 1 PID: 6425 Comm: syz Kdump: loaded Not tainted 4.19.90-vhulk2201.1.0.h1035.kasan.eulerosv2r10.aarch64 #1
[ 168.567573] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
[ 168.567575] Call trace:
[ 168.567578] dump_backtrace+0x0/0x310
[ 168.567582] show_stack+0x28/0x38
[ 168.567586] dump_stack+0xec/0x15c
[ 168.567591] kasan_report+0x244/0x2f0
[ 168.567594] __asan_load4+0x58/0xb0
[ 168.567607] virtio_gpu_conn_get_modes+0xb4/0x140 [virtio_gpu]
[ 168.567612] drm_helper_probe_single_connector_modes+0x3a4/0xd80
[ 168.567617] drm_mode_getconnector+0x2e0/0xa70
[ 168.567621] drm_ioctl_kernel+0x11c/0x1d8
[ 168.567624] drm_ioctl+0x558/0x6d0
[ 168.567628] do_vfs_ioctl+0x160/0xf30
[ 168.567632] ksys_ioctl+0x98/0xd8
[ 168.567636] __arm64_sys_ioctl+0x50/0xc8
[ 168.567641] el0_svc_common+0xc8/0x320
[ 168.567645] el0_svc_handler+0xf8/0x160
[ 168.567649] el0_svc+0x10/0x218
Signed-off-by: Liu Zixian <liuzixian4@huawei.com>
---
drivers/gpu/drm/virtio/virtgpu_display.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/gpu/drm/virtio/virtgpu_display.c b/drivers/gpu/drm/virtio/virtgpu_display.c
index 5b00310ac..f73352e7b 100644
--- a/drivers/gpu/drm/virtio/virtgpu_display.c
+++ b/drivers/gpu/drm/virtio/virtgpu_display.c
@@ -179,6 +179,8 @@ static int virtio_gpu_conn_get_modes(struct drm_connector *connector)
DRM_DEBUG("add mode: %dx%d\n", width, height);
mode = drm_cvt_mode(connector->dev, width, height, 60,
false, false, false);
+ if (!mode)
+ return count;
mode->type |= DRM_MODE_TYPE_PREFERRED;
drm_mode_probed_add(connector, mode);
count++;
--
2.33.0
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH] drm/virtio: fix NULL pointer dereference in virtio_gpu_conn_get_modes
2022-03-22 8:18 [PATCH] drm/virtio: fix NULL pointer dereference in virtio_gpu_conn_get_modes Liu Zixian
@ 2022-03-24 19:54 ` Chia-I Wu
0 siblings, 0 replies; 6+ messages in thread
From: Chia-I Wu @ 2022-03-24 19:54 UTC (permalink / raw)
To: Liu Zixian
Cc: linfeilong, ML dri-devel, open list:VIRTIO CORE, NET AND BLOCK DRIVERS
On Wed, Mar 23, 2022 at 4:01 AM Liu Zixian <liuzixian4@huawei.com> wrote:
> diff --git a/drivers/gpu/drm/virtio/virtgpu_display.c b/drivers/gpu/drm/virtio/virtgpu_display.c
> index 5b00310ac..f73352e7b 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_display.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_display.c
> @@ -179,6 +179,8 @@ static int virtio_gpu_conn_get_modes(struct drm_connector *connector)
> DRM_DEBUG("add mode: %dx%d\n", width, height);
> mode = drm_cvt_mode(connector->dev, width, height, 60,
> false, false, false);
> + if (!mode)
> + return count;
> mode->type |= DRM_MODE_TYPE_PREFERRED;
> drm_mode_probed_add(connector, mode);
> count++;
Can we avoid early return here? Something like
mode = drm_cvt_mode(...);
if (mode) {
DRM_DEBUG("add mode: %dx%d\n", width, height);
mode->type |= DRM_MODE_TYPE_PREFERRED
drm_mode_probed_add(connector, mode);
count++;
}
is more future proof.
> --
> 2.33.0
>
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] drm/virtio: fix NULL pointer dereference in virtio_gpu_conn_get_modes
@ 2022-03-24 19:54 ` Chia-I Wu
0 siblings, 0 replies; 6+ messages in thread
From: Chia-I Wu @ 2022-03-24 19:54 UTC (permalink / raw)
To: Liu Zixian
Cc: linfeilong, ML dri-devel, open list:VIRTIO CORE, NET AND BLOCK DRIVERS
On Wed, Mar 23, 2022 at 4:01 AM Liu Zixian <liuzixian4@huawei.com> wrote:
> diff --git a/drivers/gpu/drm/virtio/virtgpu_display.c b/drivers/gpu/drm/virtio/virtgpu_display.c
> index 5b00310ac..f73352e7b 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_display.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_display.c
> @@ -179,6 +179,8 @@ static int virtio_gpu_conn_get_modes(struct drm_connector *connector)
> DRM_DEBUG("add mode: %dx%d\n", width, height);
> mode = drm_cvt_mode(connector->dev, width, height, 60,
> false, false, false);
> + if (!mode)
> + return count;
> mode->type |= DRM_MODE_TYPE_PREFERRED;
> drm_mode_probed_add(connector, mode);
> count++;
Can we avoid early return here? Something like
mode = drm_cvt_mode(...);
if (mode) {
DRM_DEBUG("add mode: %dx%d\n", width, height);
mode->type |= DRM_MODE_TYPE_PREFERRED
drm_mode_probed_add(connector, mode);
count++;
}
is more future proof.
> --
> 2.33.0
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH] drm/virtio: fix NULL pointer dereference in virtio_gpu_conn_get_modes
@ 2022-03-22 9:17 ` Liu Zixian via Virtualization
0 siblings, 0 replies; 6+ messages in thread
From: Liu Zixian @ 2022-03-22 9:17 UTC (permalink / raw)
To: airlied, kraxel, gurchetansingh, olvaffe, daniel, dri-devel,
virtualization
Cc: linfeilong, liuzixian4
drm_cvt_mode may return NULL and we should check it.
This bug is found by syzkaller:
FAULT_INJECTION stacktrace:
[ 168.567394] FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 1
[ 168.567403] CPU: 1 PID: 6425 Comm: syz Kdump: loaded Not tainted 4.19.90-vhulk2201.1.0.h1035.kasan.eulerosv2r10.aarch64 #1
[ 168.567406] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
[ 168.567408] Call trace:
[ 168.567414] dump_backtrace+0x0/0x310
[ 168.567418] show_stack+0x28/0x38
[ 168.567423] dump_stack+0xec/0x15c
[ 168.567427] should_fail+0x3ac/0x3d0
[ 168.567437] __should_failslab+0xb8/0x120
[ 168.567441] should_failslab+0x28/0xc0
[ 168.567445] kmem_cache_alloc_trace+0x50/0x640
[ 168.567454] drm_mode_create+0x40/0x90
[ 168.567458] drm_cvt_mode+0x48/0xc78
[ 168.567477] virtio_gpu_conn_get_modes+0xa8/0x140 [virtio_gpu]
[ 168.567485] drm_helper_probe_single_connector_modes+0x3a4/0xd80
[ 168.567492] drm_mode_getconnector+0x2e0/0xa70
[ 168.567496] drm_ioctl_kernel+0x11c/0x1d8
[ 168.567514] drm_ioctl+0x558/0x6d0
[ 168.567522] do_vfs_ioctl+0x160/0xf30
[ 168.567525] ksys_ioctl+0x98/0xd8
[ 168.567530] __arm64_sys_ioctl+0x50/0xc8
[ 168.567536] el0_svc_common+0xc8/0x320
[ 168.567540] el0_svc_handler+0xf8/0x160
[ 168.567544] el0_svc+0x10/0x218
KASAN stacktrace:
[ 168.567561] BUG: KASAN: null-ptr-deref in virtio_gpu_conn_get_modes+0xb4/0x140 [virtio_gpu]
[ 168.567565] Read of size 4 at addr 0000000000000054 by task syz/6425
[ 168.567566]
[ 168.567571] CPU: 1 PID: 6425 Comm: syz Kdump: loaded Not tainted 4.19.90-vhulk2201.1.0.h1035.kasan.eulerosv2r10.aarch64 #1
[ 168.567573] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
[ 168.567575] Call trace:
[ 168.567578] dump_backtrace+0x0/0x310
[ 168.567582] show_stack+0x28/0x38
[ 168.567586] dump_stack+0xec/0x15c
[ 168.567591] kasan_report+0x244/0x2f0
[ 168.567594] __asan_load4+0x58/0xb0
[ 168.567607] virtio_gpu_conn_get_modes+0xb4/0x140 [virtio_gpu]
[ 168.567612] drm_helper_probe_single_connector_modes+0x3a4/0xd80
[ 168.567617] drm_mode_getconnector+0x2e0/0xa70
[ 168.567621] drm_ioctl_kernel+0x11c/0x1d8
[ 168.567624] drm_ioctl+0x558/0x6d0
[ 168.567628] do_vfs_ioctl+0x160/0xf30
[ 168.567632] ksys_ioctl+0x98/0xd8
[ 168.567636] __arm64_sys_ioctl+0x50/0xc8
[ 168.567641] el0_svc_common+0xc8/0x320
[ 168.567645] el0_svc_handler+0xf8/0x160
[ 168.567649] el0_svc+0x10/0x218
Signed-off-by: Liu Zixian <liuzixian4@huawei.com>
---
drivers/gpu/drm/virtio/virtgpu_display.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/gpu/drm/virtio/virtgpu_display.c b/drivers/gpu/drm/virtio/virtgpu_display.c
index 5b00310ac..f73352e7b 100644
--- a/drivers/gpu/drm/virtio/virtgpu_display.c
+++ b/drivers/gpu/drm/virtio/virtgpu_display.c
@@ -179,6 +179,8 @@ static int virtio_gpu_conn_get_modes(struct drm_connector *connector)
DRM_DEBUG("add mode: %dx%d\n", width, height);
mode = drm_cvt_mode(connector->dev, width, height, 60,
false, false, false);
+ if (!mode)
+ return count;
mode->type |= DRM_MODE_TYPE_PREFERRED;
drm_mode_probed_add(connector, mode);
count++;
--
2.33.0
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH] drm/virtio: fix NULL pointer dereference in virtio_gpu_conn_get_modes
@ 2022-03-22 9:17 ` Liu Zixian via Virtualization
0 siblings, 0 replies; 6+ messages in thread
From: Liu Zixian via Virtualization @ 2022-03-22 9:17 UTC (permalink / raw)
To: airlied, kraxel, gurchetansingh, olvaffe, daniel, dri-devel,
virtualization
Cc: linfeilong
drm_cvt_mode may return NULL and we should check it.
This bug is found by syzkaller:
FAULT_INJECTION stacktrace:
[ 168.567394] FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 1
[ 168.567403] CPU: 1 PID: 6425 Comm: syz Kdump: loaded Not tainted 4.19.90-vhulk2201.1.0.h1035.kasan.eulerosv2r10.aarch64 #1
[ 168.567406] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
[ 168.567408] Call trace:
[ 168.567414] dump_backtrace+0x0/0x310
[ 168.567418] show_stack+0x28/0x38
[ 168.567423] dump_stack+0xec/0x15c
[ 168.567427] should_fail+0x3ac/0x3d0
[ 168.567437] __should_failslab+0xb8/0x120
[ 168.567441] should_failslab+0x28/0xc0
[ 168.567445] kmem_cache_alloc_trace+0x50/0x640
[ 168.567454] drm_mode_create+0x40/0x90
[ 168.567458] drm_cvt_mode+0x48/0xc78
[ 168.567477] virtio_gpu_conn_get_modes+0xa8/0x140 [virtio_gpu]
[ 168.567485] drm_helper_probe_single_connector_modes+0x3a4/0xd80
[ 168.567492] drm_mode_getconnector+0x2e0/0xa70
[ 168.567496] drm_ioctl_kernel+0x11c/0x1d8
[ 168.567514] drm_ioctl+0x558/0x6d0
[ 168.567522] do_vfs_ioctl+0x160/0xf30
[ 168.567525] ksys_ioctl+0x98/0xd8
[ 168.567530] __arm64_sys_ioctl+0x50/0xc8
[ 168.567536] el0_svc_common+0xc8/0x320
[ 168.567540] el0_svc_handler+0xf8/0x160
[ 168.567544] el0_svc+0x10/0x218
KASAN stacktrace:
[ 168.567561] BUG: KASAN: null-ptr-deref in virtio_gpu_conn_get_modes+0xb4/0x140 [virtio_gpu]
[ 168.567565] Read of size 4 at addr 0000000000000054 by task syz/6425
[ 168.567566]
[ 168.567571] CPU: 1 PID: 6425 Comm: syz Kdump: loaded Not tainted 4.19.90-vhulk2201.1.0.h1035.kasan.eulerosv2r10.aarch64 #1
[ 168.567573] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
[ 168.567575] Call trace:
[ 168.567578] dump_backtrace+0x0/0x310
[ 168.567582] show_stack+0x28/0x38
[ 168.567586] dump_stack+0xec/0x15c
[ 168.567591] kasan_report+0x244/0x2f0
[ 168.567594] __asan_load4+0x58/0xb0
[ 168.567607] virtio_gpu_conn_get_modes+0xb4/0x140 [virtio_gpu]
[ 168.567612] drm_helper_probe_single_connector_modes+0x3a4/0xd80
[ 168.567617] drm_mode_getconnector+0x2e0/0xa70
[ 168.567621] drm_ioctl_kernel+0x11c/0x1d8
[ 168.567624] drm_ioctl+0x558/0x6d0
[ 168.567628] do_vfs_ioctl+0x160/0xf30
[ 168.567632] ksys_ioctl+0x98/0xd8
[ 168.567636] __arm64_sys_ioctl+0x50/0xc8
[ 168.567641] el0_svc_common+0xc8/0x320
[ 168.567645] el0_svc_handler+0xf8/0x160
[ 168.567649] el0_svc+0x10/0x218
Signed-off-by: Liu Zixian <liuzixian4@huawei.com>
---
drivers/gpu/drm/virtio/virtgpu_display.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/gpu/drm/virtio/virtgpu_display.c b/drivers/gpu/drm/virtio/virtgpu_display.c
index 5b00310ac..f73352e7b 100644
--- a/drivers/gpu/drm/virtio/virtgpu_display.c
+++ b/drivers/gpu/drm/virtio/virtgpu_display.c
@@ -179,6 +179,8 @@ static int virtio_gpu_conn_get_modes(struct drm_connector *connector)
DRM_DEBUG("add mode: %dx%d\n", width, height);
mode = drm_cvt_mode(connector->dev, width, height, 60,
false, false, false);
+ if (!mode)
+ return count;
mode->type |= DRM_MODE_TYPE_PREFERRED;
drm_mode_probed_add(connector, mode);
count++;
--
2.33.0
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH] drm/virtio: fix NULL pointer dereference in virtio_gpu_conn_get_modes
@ 2022-03-21 7:09 Liu Zixian
0 siblings, 0 replies; 6+ messages in thread
From: Liu Zixian @ 2022-03-21 7:09 UTC (permalink / raw)
To: dri-devel, virtualization; +Cc: linfeilong
drm_cvt_mode may return NULL and we should check it.
This bug is found by syzkaller:
FAULT_INJECTION stacktrace:
[ 168.567394] FAULT_INJECTION: forcing a failure.
name failslab, interval 1, probability 0, space 0, times 1
[ 168.567403] CPU: 1 PID: 6425 Comm: syz Kdump: loaded Not tainted 4.19.90-vhulk2201.1.0.h1035.kasan.eulerosv2r10.aarch64 #1
[ 168.567406] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
[ 168.567408] Call trace:
[ 168.567414] dump_backtrace+0x0/0x310
[ 168.567418] show_stack+0x28/0x38
[ 168.567423] dump_stack+0xec/0x15c
[ 168.567427] should_fail+0x3ac/0x3d0
[ 168.567437] __should_failslab+0xb8/0x120
[ 168.567441] should_failslab+0x28/0xc0
[ 168.567445] kmem_cache_alloc_trace+0x50/0x640
[ 168.567454] drm_mode_create+0x40/0x90
[ 168.567458] drm_cvt_mode+0x48/0xc78
[ 168.567477] virtio_gpu_conn_get_modes+0xa8/0x140 [virtio_gpu]
[ 168.567485] drm_helper_probe_single_connector_modes+0x3a4/0xd80
[ 168.567492] drm_mode_getconnector+0x2e0/0xa70
[ 168.567496] drm_ioctl_kernel+0x11c/0x1d8
[ 168.567514] drm_ioctl+0x558/0x6d0
[ 168.567522] do_vfs_ioctl+0x160/0xf30
[ 168.567525] ksys_ioctl+0x98/0xd8
[ 168.567530] __arm64_sys_ioctl+0x50/0xc8
[ 168.567536] el0_svc_common+0xc8/0x320
[ 168.567540] el0_svc_handler+0xf8/0x160
[ 168.567544] el0_svc+0x10/0x218
KASAN stacktrace:
[ 168.567561] BUG: KASAN: null-ptr-deref in virtio_gpu_conn_get_modes+0xb4/0x140 [virtio_gpu]
[ 168.567565] Read of size 4 at addr 0000000000000054 by task syz/6425
[ 168.567566]
[ 168.567571] CPU: 1 PID: 6425 Comm: syz Kdump: loaded Not tainted 4.19.90-vhulk2201.1.0.h1035.kasan.eulerosv2r10.aarch64 #1
[ 168.567573] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
[ 168.567575] Call trace:
[ 168.567578] dump_backtrace+0x0/0x310
[ 168.567582] show_stack+0x28/0x38
[ 168.567586] dump_stack+0xec/0x15c
[ 168.567591] kasan_report+0x244/0x2f0
[ 168.567594] __asan_load4+0x58/0xb0
[ 168.567607] virtio_gpu_conn_get_modes+0xb4/0x140 [virtio_gpu]
[ 168.567612] drm_helper_probe_single_connector_modes+0x3a4/0xd80
[ 168.567617] drm_mode_getconnector+0x2e0/0xa70
[ 168.567621] drm_ioctl_kernel+0x11c/0x1d8
[ 168.567624] drm_ioctl+0x558/0x6d0
[ 168.567628] do_vfs_ioctl+0x160/0xf30
[ 168.567632] ksys_ioctl+0x98/0xd8
[ 168.567636] __arm64_sys_ioctl+0x50/0xc8
[ 168.567641] el0_svc_common+0xc8/0x320
[ 168.567645] el0_svc_handler+0xf8/0x160
[ 168.567649] el0_svc+0x10/0x218
Signed-off-by: Liu Zixian <liuzixian4@huawei.com>
---
drivers/gpu/drm/virtio/virtgpu_display.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/gpu/drm/virtio/virtgpu_display.c b/drivers/gpu/drm/virtio/virtgpu_display.c
index 5b00310ac..f73352e7b 100644
--- a/drivers/gpu/drm/virtio/virtgpu_display.c
+++ b/drivers/gpu/drm/virtio/virtgpu_display.c
@@ -179,6 +179,8 @@ static int virtio_gpu_conn_get_modes(struct drm_connector *connector)
DRM_DEBUG("add mode: %dx%d\n", width, height);
mode = drm_cvt_mode(connector->dev, width, height, 60,
false, false, false);
+ if (!mode)
+ return count;
mode->type |= DRM_MODE_TYPE_PREFERRED;
drm_mode_probed_add(connector, mode);
count++;
--
2.33.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2022-03-24 19:54 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-03-22 8:18 [PATCH] drm/virtio: fix NULL pointer dereference in virtio_gpu_conn_get_modes Liu Zixian
2022-03-24 19:54 ` Chia-I Wu
2022-03-24 19:54 ` Chia-I Wu
-- strict thread matches above, loose matches on Subject: below --
2022-03-22 9:17 Liu Zixian
2022-03-22 9:17 ` Liu Zixian via Virtualization
2022-03-21 7:09 Liu Zixian
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