Since we need to be able to allow DPMS on->off prop changes after an MST
port has disappeared from the system, we need to be able to make sure we
can compute a config for the resulting atomic commit. Currently this is
impossible when the port has disappeared, since the VCPI slot searching
we try to do in intel_dp_mst_compute_config() will fail with -EINVAL.
Since the only commits we want to allow on no-longer-present MST ports
are ones that shut off display hardware, we already know that no VCPI
allocations are needed. So, hardcode the VCPI slot count to 0 when
intel_dp_mst_compute_config() is called on an MST port that's gone.
Signed-off-by: Lyude Paul <lyude(a)redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter(a)ffwll.ch>
Cc: stable(a)vger.kernel.org
Changes since V4:
- Don't use mst_port_gone at all, just check whether or not the drm
connector is registered - Daniel Vetter
Signed-off-by: Lyude Paul <lyude(a)redhat.com>
---
drivers/gpu/drm/i915/intel_dp_mst.c | 24 +++++++++++++++---------
1 file changed, 15 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c
index aa21742d8634..0f14c0d1669c 100644
--- a/drivers/gpu/drm/i915/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/intel_dp_mst.c
@@ -38,11 +38,11 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
struct intel_dp_mst_encoder *intel_mst = enc_to_mst(&encoder->base);
struct intel_digital_port *intel_dig_port = intel_mst->primary;
struct intel_dp *intel_dp = &intel_dig_port->dp;
- struct intel_connector *connector =
- to_intel_connector(conn_state->connector);
+ struct drm_connector *connector = conn_state->connector;
+ void *port = to_intel_connector(connector)->port;
struct drm_atomic_state *state = pipe_config->base.state;
int bpp;
- int lane_count, slots;
+ int lane_count, slots = 0;
const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
int mst_pbn;
bool constant_n = drm_dp_has_quirk(&intel_dp->desc,
@@ -70,17 +70,23 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
pipe_config->port_clock = intel_dp_max_link_rate(intel_dp);
- if (drm_dp_mst_port_has_audio(&intel_dp->mst_mgr, connector->port))
+ if (drm_dp_mst_port_has_audio(&intel_dp->mst_mgr, port))
pipe_config->has_audio = true;
mst_pbn = drm_dp_calc_pbn_mode(adjusted_mode->crtc_clock, bpp);
pipe_config->pbn = mst_pbn;
- slots = drm_dp_atomic_find_vcpi_slots(state, &intel_dp->mst_mgr,
- connector->port, mst_pbn);
- if (slots < 0) {
- DRM_DEBUG_KMS("failed finding vcpi slots:%d\n", slots);
- return false;
+ /* Zombie connectors can't have VCPI slots */
+ if (READ_ONCE(connector->registered)) {
+ slots = drm_dp_atomic_find_vcpi_slots(state,
+ &intel_dp->mst_mgr,
+ port,
+ mst_pbn);
+ if (slots < 0) {
+ DRM_DEBUG_KMS("failed finding vcpi slots:%d\n",
+ slots);
+ return false;
+ }
}
intel_link_compute_m_n(bpp, lane_count,
--
2.17.1
Currently we set intel_connector->mst_port to NULL to signify that the
MST port has been removed from the system so that we can prevent further
action on the port such as connector probes, mode probing, etc.
However, we're going to need access to intel_connector->mst_port in
order to fixup ->best_encoder() so that it can always return the correct
encoder for an MST port to prevent legacy DPMS prop changes from
failing. This should be safe, so instead keep intel_connector->mst_port
always set and instead just check the status of
drm_connector->regustered to signify whether or not the connector has
disappeared from the system.
Changes since v2:
- Add a comment to mst_port_gone (Jani Nikula)
- Change mst_port_gone to a u8 instead of a bool, per the kernel bot.
Apparently bool is discouraged in structs these days
Changes since v4:
- Don't use mst_port_gone at all! Just check if the connector is
registered or not - Daniel Vetter
Signed-off-by: Lyude Paul <lyude(a)redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter(a)ffwll.ch>
Cc: stable(a)vger.kernel.org
---
drivers/gpu/drm/i915/intel_dp_mst.c | 17 ++++++-----------
1 file changed, 6 insertions(+), 11 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c
index 43db2e9ac575..aa21742d8634 100644
--- a/drivers/gpu/drm/i915/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/intel_dp_mst.c
@@ -307,9 +307,8 @@ static int intel_dp_mst_get_ddc_modes(struct drm_connector *connector)
struct edid *edid;
int ret;
- if (!intel_dp) {
+ if (!READ_ONCE(connector->registered))
return intel_connector_update_modes(connector, NULL);
- }
edid = drm_dp_mst_get_edid(connector, &intel_dp->mst_mgr, intel_connector->port);
ret = intel_connector_update_modes(connector, edid);
@@ -324,9 +323,10 @@ intel_dp_mst_detect(struct drm_connector *connector, bool force)
struct intel_connector *intel_connector = to_intel_connector(connector);
struct intel_dp *intel_dp = intel_connector->mst_port;
- if (!intel_dp)
+ if (!READ_ONCE(connector->registered))
return connector_status_disconnected;
- return drm_dp_mst_detect_port(connector, &intel_dp->mst_mgr, intel_connector->port);
+ return drm_dp_mst_detect_port(connector, &intel_dp->mst_mgr,
+ intel_connector->port);
}
static void
@@ -366,7 +366,7 @@ intel_dp_mst_mode_valid(struct drm_connector *connector,
int bpp = 24; /* MST uses fixed bpp */
int max_rate, mode_rate, max_lanes, max_link_clock;
- if (!intel_dp)
+ if (!READ_ONCE(connector->registered))
return MODE_ERROR;
if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
@@ -398,7 +398,7 @@ static struct drm_encoder *intel_mst_atomic_best_encoder(struct drm_connector *c
struct intel_dp *intel_dp = intel_connector->mst_port;
struct intel_crtc *crtc = to_intel_crtc(state->crtc);
- if (!intel_dp)
+ if (!READ_ONCE(connector->registered))
return NULL;
return &intel_dp->mst_encoders[crtc->pipe]->base.base;
}
@@ -499,7 +499,6 @@ static void intel_dp_register_mst_connector(struct drm_connector *connector)
static void intel_dp_destroy_mst_connector(struct drm_dp_mst_topology_mgr *mgr,
struct drm_connector *connector)
{
- struct intel_connector *intel_connector = to_intel_connector(connector);
struct drm_i915_private *dev_priv = to_i915(connector->dev);
DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n", connector->base.id, connector->name);
@@ -508,10 +507,6 @@ static void intel_dp_destroy_mst_connector(struct drm_dp_mst_topology_mgr *mgr,
if (dev_priv->fbdev)
drm_fb_helper_remove_one_connector(&dev_priv->fbdev->helper,
connector);
- /* prevent race with the check in ->detect */
- drm_modeset_lock(&connector->dev->mode_config.connection_mutex, NULL);
- intel_connector->mst_port = NULL;
- drm_modeset_unlock(&connector->dev->mode_config.connection_mutex);
drm_connector_put(connector);
}
--
2.17.1
As mentioned in the previous commit, we currently prevent new modesets
on recently-removed MST connectors by returning no encoder from our
->best_encoder() callback once the MST port has disappeared. This is
wrong however, because it prevents legacy modesetting users from being
able to disable CRTCs on MST connectors after the connector's respective
topology has disappeared.
So, fix this by instead by just always returning a valid encoder.
Changes since v2:
- Remove usage of atomic MST helper for now, since that got replaced
with a much simpler solution
Signed-off-by: Lyude Paul <lyude(a)redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter(a)ffwll.ch>
Cc: stable(a)vger.kernel.org
---
drivers/gpu/drm/nouveau/dispnv50/disp.c | 14 ++++----------
1 file changed, 4 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/dispnv50/disp.c b/drivers/gpu/drm/nouveau/dispnv50/disp.c
index 9f32b10c7c29..31b94bc9ec90 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/disp.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/disp.c
@@ -843,22 +843,16 @@ nv50_mstc_atomic_best_encoder(struct drm_connector *connector,
{
struct nv50_head *head = nv50_head(connector_state->crtc);
struct nv50_mstc *mstc = nv50_mstc(connector);
- if (mstc->port) {
- struct nv50_mstm *mstm = mstc->mstm;
- return &mstm->msto[head->base.index]->encoder;
- }
- return NULL;
+
+ return &mstc->mstm->msto[head->base.index]->encoder;
}
static struct drm_encoder *
nv50_mstc_best_encoder(struct drm_connector *connector)
{
struct nv50_mstc *mstc = nv50_mstc(connector);
- if (mstc->port) {
- struct nv50_mstm *mstm = mstc->mstm;
- return &mstm->msto[0]->encoder;
- }
- return NULL;
+
+ return &mstc->mstm->msto[0]->encoder;
}
static enum drm_mode_status
--
2.17.1
With the exception of modesets which would switch the DPMS state of a
connector from on to off, we want to make sure that we disallow all
modesets which would result in enabling a new monitor or a new mode
configuration on a monitor if the connector for the display in question
is no longer registered. This allows us to stop userspace from trying to
enable new displays on connectors for an MST topology that were just
removed from the system, without preventing userspace from disabling
DPMS on those connectors.
Signed-off-by: Lyude Paul <lyude(a)redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter(a)ffwll.ch>
Cc: stable(a)vger.kernel.org
---
drivers/gpu/drm/drm_atomic_helper.c | 21 ++++++++++++++++++++-
1 file changed, 20 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 6f66777dca4b..788749021ac9 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -319,6 +319,26 @@ update_connector_routing(struct drm_atomic_state *state,
return 0;
}
+ crtc_state = drm_atomic_get_new_crtc_state(state,
+ new_connector_state->crtc);
+ /*
+ * For compatibility with legacy users, we want to make sure that
+ * we allow DPMS On->Off modesets on unregistered connectors. Modesets
+ * which would result in anything else must be considered invalid, to
+ * avoid turning on new displays on dead connectors.
+ *
+ * Since the connector can be unregistered at any point during an
+ * atomic check or commit, this is racy. But that's OK: all we care
+ * about is ensuring that userspace can't do anything but shut off the
+ * display on a connector that was destroyed after it's been notified,
+ * not before.
+ */
+ if (!READ_ONCE(connector->registered) && crtc_state->active) {
+ DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] is not registered\n",
+ connector->base.id, connector->name);
+ return -EINVAL;
+ }
+
funcs = connector->helper_private;
if (funcs->atomic_best_encoder)
@@ -363,7 +383,6 @@ update_connector_routing(struct drm_atomic_state *state,
set_best_encoder(state, new_connector_state, new_encoder);
- crtc_state = drm_atomic_get_new_crtc_state(state, new_connector_state->crtc);
crtc_state->connectors_changed = true;
DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] using [ENCODER:%d:%s] on [CRTC:%d:%s]\n",
--
2.17.1
From: Sudip Mukherjee <sudipm.mukherjee(a)gmail.com>
The port number is checked and it just prints an error message but it
still continues to use the invalid port. And as a result it accesses
memory which is not its resulting in BUG report from KASAN.
Reported-by: syzbot+600b03e0cf1b73bb23c4(a)syzkaller.appspotmail.com
Cc: stable <stable(a)vger.kernel.org>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee(a)gmail.com>
---
drivers/usb/usbip/vhci_hcd.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/usbip/vhci_hcd.c b/drivers/usb/usbip/vhci_hcd.c
index d11f3f8dad40..71883aa788ac 100644
--- a/drivers/usb/usbip/vhci_hcd.c
+++ b/drivers/usb/usbip/vhci_hcd.c
@@ -334,8 +334,10 @@ static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
usbip_dbg_vhci_rh("typeReq %x wValue %x wIndex %x\n", typeReq, wValue,
wIndex);
- if (wIndex > VHCI_HC_PORTS)
+ if (wIndex > VHCI_HC_PORTS) {
pr_err("invalid port number %d\n", wIndex);
+ return -ENODEV;
+ }
rhport = wIndex - 1;
vhci_hcd = hcd_to_vhci_hcd(hcd);
--
2.11.0
The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 7012040576c6ae25a47035659ee48673612c2c27 Mon Sep 17 00:00:00 2001
From: Bjorn Andersson <bjorn.andersson(a)linaro.org>
Date: Wed, 19 Sep 2018 18:09:38 -0700
Subject: [PATCH] firmware: Always initialize the fw_priv list object
When freeing the fw_priv the item is taken off the list. This causes an
oops in the FW_OPT_NOCACHE case as the list object is not initialized.
Make sure to initialize the list object regardless of this flag.
Fixes: 422b3db2a503 ("firmware: Fix security issue with request_firmware_into_buf()")
Cc: stable(a)vger.kernel.org
Cc: Rishabh Bhatnagar <rishabhb(a)codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson(a)linaro.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c
index b3c0498ee433..8e9213b36e31 100644
--- a/drivers/base/firmware_loader/main.c
+++ b/drivers/base/firmware_loader/main.c
@@ -226,8 +226,11 @@ static int alloc_lookup_fw_priv(const char *fw_name,
}
tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size);
- if (tmp && !(opt_flags & FW_OPT_NOCACHE))
- list_add(&tmp->list, &fwc->head);
+ if (tmp) {
+ INIT_LIST_HEAD(&tmp->list);
+ if (!(opt_flags & FW_OPT_NOCACHE))
+ list_add(&tmp->list, &fwc->head);
+ }
spin_unlock(&fwc->lock);
*fw_priv = tmp;
The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 422b3db2a5036add39a82425b1dd9fb6c96481e8 Mon Sep 17 00:00:00 2001
From: Rishabh Bhatnagar <rishabhb(a)codeaurora.org>
Date: Fri, 31 Aug 2018 08:43:31 -0700
Subject: [PATCH] firmware: Fix security issue with request_firmware_into_buf()
When calling request_firmware_into_buf() with the FW_OPT_NOCACHE flag
it is expected that firmware is loaded into buffer from memory.
But inside alloc_lookup_fw_priv every new firmware that is loaded is
added to the firmware cache (fwc) list head. So if any driver requests
a firmware that is already loaded the code iterates over the above
mentioned list and it can end up giving a pointer to other device driver's
firmware buffer.
Also the existing copy may either be modified by drivers, remote processors
or even freed. This causes a potential security issue with batched requests
when using request_firmware_into_buf.
Fix alloc_lookup_fw_priv to not add to the fwc head list if FW_OPT_NOCACHE
is set, and also don't do the lookup in the list.
Fixes: 0e742e9275 ("firmware: provide infrastructure to make fw caching optional")
[mcgrof: broken since feature introduction on v4.8]
Cc: stable(a)vger.kernel.org # v4.8+
Signed-off-by: Vikram Mulukutla <markivx(a)codeaurora.org>
Signed-off-by: Rishabh Bhatnagar <rishabhb(a)codeaurora.org>
Signed-off-by: Luis Chamberlain <mcgrof(a)kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c
index 0943e7065e0e..b3c0498ee433 100644
--- a/drivers/base/firmware_loader/main.c
+++ b/drivers/base/firmware_loader/main.c
@@ -209,21 +209,24 @@ static struct fw_priv *__lookup_fw_priv(const char *fw_name)
static int alloc_lookup_fw_priv(const char *fw_name,
struct firmware_cache *fwc,
struct fw_priv **fw_priv, void *dbuf,
- size_t size)
+ size_t size, enum fw_opt opt_flags)
{
struct fw_priv *tmp;
spin_lock(&fwc->lock);
- tmp = __lookup_fw_priv(fw_name);
- if (tmp) {
- kref_get(&tmp->ref);
- spin_unlock(&fwc->lock);
- *fw_priv = tmp;
- pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
- return 1;
+ if (!(opt_flags & FW_OPT_NOCACHE)) {
+ tmp = __lookup_fw_priv(fw_name);
+ if (tmp) {
+ kref_get(&tmp->ref);
+ spin_unlock(&fwc->lock);
+ *fw_priv = tmp;
+ pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
+ return 1;
+ }
}
+
tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size);
- if (tmp)
+ if (tmp && !(opt_flags & FW_OPT_NOCACHE))
list_add(&tmp->list, &fwc->head);
spin_unlock(&fwc->lock);
@@ -493,7 +496,8 @@ int assign_fw(struct firmware *fw, struct device *device,
*/
static int
_request_firmware_prepare(struct firmware **firmware_p, const char *name,
- struct device *device, void *dbuf, size_t size)
+ struct device *device, void *dbuf, size_t size,
+ enum fw_opt opt_flags)
{
struct firmware *firmware;
struct fw_priv *fw_priv;
@@ -511,7 +515,8 @@ _request_firmware_prepare(struct firmware **firmware_p, const char *name,
return 0; /* assigned */
}
- ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size);
+ ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size,
+ opt_flags);
/*
* bind with 'priv' now to avoid warning in failure path
@@ -571,7 +576,8 @@ _request_firmware(const struct firmware **firmware_p, const char *name,
goto out;
}
- ret = _request_firmware_prepare(&fw, name, device, buf, size);
+ ret = _request_firmware_prepare(&fw, name, device, buf, size,
+ opt_flags);
if (ret <= 0) /* error or already assigned */
goto out;