This is a note to let you know that I've just added the patch titled
tty: do not set TTY_IO_ERROR flag if console port
to my tty git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git
in the tty-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From 2a48602615e0a2f563549c7d5c8d507f904cf96e Mon Sep 17 00:00:00 2001
From: Chanho Park <parkch98(a)gmail.com>
Date: Thu, 22 Nov 2018 18:23:47 +0900
Subject: tty: do not set TTY_IO_ERROR flag if console port
Since Commit 761ed4a94582 ('tty: serial_core: convert uart_close to use
tty_port_close') and Commit 4dda864d7307 ('tty: serial_core: Fix serial
console crash on port shutdown), a serial port which is used as
console can be stuck when logging out if there is a remained process.
After logged out, agetty will try to grab the serial port but it will
be failed because the previous process did not release the port
correctly. To fix this, TTY_IO_ERROR bit should not be enabled of
tty_port_close if the port is console port.
Reproduce step:
- Run background processes from serial console
$ while true; do sleep 10; done &
- Log out
$ logout
-> Stuck
- Read journal log by journalctl | tail
Jan 28 16:07:01 ubuntu systemd[1]: Stopped Serial Getty on ttyAMA0.
Jan 28 16:07:01 ubuntu systemd[1]: Started Serial Getty on ttyAMA0.
Jan 28 16:07:02 ubuntu agetty[1643]: /dev/ttyAMA0: not a tty
Fixes: 761ed4a94582 ("tty: serial_core: convert uart_close to use tty_port_close")
Cc: Geert Uytterhoeven <geert+renesas(a)glider.be>
Cc: Rob Herring <robh(a)kernel.org>
Cc: Jiri Slaby <jslaby(a)suse.com>
Signed-off-by: Chanho Park <parkch98(a)gmail.com>
Cc: stable <stable(a)vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/tty/tty_port.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c
index cb6075096a5b..044c3cbdcfa4 100644
--- a/drivers/tty/tty_port.c
+++ b/drivers/tty/tty_port.c
@@ -633,7 +633,8 @@ void tty_port_close(struct tty_port *port, struct tty_struct *tty,
if (tty_port_close_start(port, tty, filp) == 0)
return;
tty_port_shutdown(port, tty);
- set_bit(TTY_IO_ERROR, &tty->flags);
+ if (!port->console)
+ set_bit(TTY_IO_ERROR, &tty->flags);
tty_port_close_end(port, tty);
tty_port_tty_set(port, NULL);
}
--
2.19.2
imx274_read_reg() takes a u8 pointer ("reg") and casts it to pass it
to regmap_read(), which takes an unsigned int pointer. This results in
a corrupted stack and random crashes.
Fixes: 0985dd306f72 ("media: imx274: V4l2 driver for Sony imx274 CMOS sensor")
Cc: stable(a)vger.kernel.org # 4.15.x
Signed-off-by: Luca Ceresoli <luca(a)lucaceresoli.net>
---
Notes!
I have no evidence of this bug showing up in the mainline driver. It
appeared on a modified version where imx274_read_reg() is used,
unmodified, in a different way than it does in mainline (passing a
pointer to a single u8 instead of a pointer to an element of a u8
array).
Also the bug is only present in versions v4.15 (where the driver was
added) to v4.19. The offending function is unused since commit
ca017467c78b ("media: imx274: add helper to read multibyte
registers"), merged in v4.20-rc1, thus master is not affected. I'm
sending this bugfix patch anyway for easier integration in the stable
branches. Later I plan to send a patch against master to entirely
remove the function. Or somebody might want to use this function
again, so better having a fixed version out anyway.
I'm not 100% sure this qualifies this commit for stable trees.
---
drivers/media/i2c/imx274.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/media/i2c/imx274.c b/drivers/media/i2c/imx274.c
index e1b0395a657f..40c717f13eb8 100644
--- a/drivers/media/i2c/imx274.c
+++ b/drivers/media/i2c/imx274.c
@@ -619,16 +619,19 @@ static int imx274_write_table(struct stimx274 *priv, const struct reg_8 table[])
static inline int imx274_read_reg(struct stimx274 *priv, u16 addr, u8 *val)
{
+ unsigned int uint_val;
int err;
- err = regmap_read(priv->regmap, addr, (unsigned int *)val);
+ err = regmap_read(priv->regmap, addr, &uint_val);
if (err)
dev_err(&priv->client->dev,
"%s : i2c read failed, addr = %x\n", __func__, addr);
else
dev_dbg(&priv->client->dev,
"%s : addr 0x%x, val=0x%x\n", __func__,
- addr, *val);
+ addr, uint_val);
+
+ *val = uint_val;
return err;
}
--
2.17.1
In order for ULPI PHYs to work, dwc3_phy_setup() and dwc3_ulpi_init()
must be doene before dwc3_core_get_phy().
commit 541768b08a40 ("usb: dwc3: core: Call dwc3_core_get_phy() before initializing phys")
broke this.
The other issue is that dwc3_core_get_phy() and dwc3_ulpi_init() should
be called only once during the life cycle of the driver. However,
as dwc3_core_init() is called during system suspend/resume it will
result in multiple calls to dwc3_core_get_phy() and dwc3_ulpi_init()
which is wrong.
Fix this by moving dwc3_ulpi_init() out of dwc3_phy_setup()
into dwc3_core_ulpi_init(). Use a flag 'ulpi_ready' to ensure that
dwc3_core_ulpi_init() is called only once from dwc3_core_init().
Use another flag 'phys_ready' to call dwc3_core_get_phy() only once from
dwc3_core_init().
Fixes: 541768b08a40 ("usb: dwc3: core: Call dwc3_core_get_phy() before initializing phys")
Fixes: f54edb539c11 ("usb: dwc3: core: initialize ULPI before trying to get the PHY")
Cc: linux-stable <stable(a)vger.kernel.org> # >= v4.13
Signed-off-by: Roger Quadros <rogerq(a)ti.com>
---
Changelog:
v2:
- don't break ULPI case. Also take into consideration suspend/resume for ULPI case.
drivers/usb/dwc3/core.c | 47 ++++++++++++++++++++++++++++++++++++-----------
drivers/usb/dwc3/core.h | 5 +++++
2 files changed, 41 insertions(+), 11 deletions(-)
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 0783250..84382f6 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -482,6 +482,22 @@ static void dwc3_cache_hwparams(struct dwc3 *dwc)
parms->hwparams8 = dwc3_readl(dwc->regs, DWC3_GHWPARAMS8);
}
+static int dwc3_core_ulpi_init(struct dwc3 *dwc)
+{
+ int intf;
+ int ret = 0;
+
+ intf = DWC3_GHWPARAMS3_HSPHY_IFC(dwc->hwparams.hwparams3);
+
+ if (intf == DWC3_GHWPARAMS3_HSPHY_IFC_ULPI ||
+ (intf == DWC3_GHWPARAMS3_HSPHY_IFC_UTMI_ULPI &&
+ dwc->hsphy_interface &&
+ !strncmp(dwc->hsphy_interface, "ulpi", 4)))
+ ret = dwc3_ulpi_init(dwc);
+
+ return ret;
+}
+
/**
* dwc3_phy_setup - Configure USB PHY Interface of DWC3 Core
* @dwc: Pointer to our controller context structure
@@ -493,7 +509,6 @@ static void dwc3_cache_hwparams(struct dwc3 *dwc)
static int dwc3_phy_setup(struct dwc3 *dwc)
{
u32 reg;
- int ret;
reg = dwc3_readl(dwc->regs, DWC3_GUSB3PIPECTL(0));
@@ -564,9 +579,6 @@ static int dwc3_phy_setup(struct dwc3 *dwc)
}
/* FALLTHROUGH */
case DWC3_GHWPARAMS3_HSPHY_IFC_ULPI:
- ret = dwc3_ulpi_init(dwc);
- if (ret)
- return ret;
/* FALLTHROUGH */
default:
break;
@@ -723,6 +735,7 @@ static void dwc3_core_setup_global_control(struct dwc3 *dwc)
}
static int dwc3_core_get_phy(struct dwc3 *dwc);
+static int dwc3_core_ulpi_init(struct dwc3 *dwc);
/**
* dwc3_core_init - Low-level initialization of DWC3 Core
@@ -754,17 +767,27 @@ static int dwc3_core_init(struct dwc3 *dwc)
dwc->maximum_speed = USB_SPEED_HIGH;
}
- ret = dwc3_core_get_phy(dwc);
+ ret = dwc3_phy_setup(dwc);
if (ret)
goto err0;
- ret = dwc3_core_soft_reset(dwc);
- if (ret)
- goto err0;
+ if (!dwc->ulpi_ready) {
+ ret = dwc3_core_ulpi_init(dwc);
+ if (ret)
+ goto err0;
+ dwc->ulpi_ready = true;
+ }
- ret = dwc3_phy_setup(dwc);
+ if (!dwc->phys_ready) {
+ ret = dwc3_core_get_phy(dwc);
+ if (ret)
+ goto err0a;
+ dwc->phys_ready = true;
+ }
+
+ ret = dwc3_core_soft_reset(dwc);
if (ret)
- goto err0;
+ goto err0a;
dwc3_core_setup_global_control(dwc);
dwc3_core_num_eps(dwc);
@@ -837,6 +860,9 @@ static int dwc3_core_init(struct dwc3 *dwc)
phy_exit(dwc->usb2_generic_phy);
phy_exit(dwc->usb3_generic_phy);
+err0a:
+ dwc3_ulpi_exit(dwc);
+
err0:
return ret;
}
@@ -1229,7 +1255,6 @@ static int dwc3_probe(struct platform_device *pdev)
err3:
dwc3_free_event_buffers(dwc);
- dwc3_ulpi_exit(dwc);
err2:
pm_runtime_allow(&pdev->dev);
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 4a4a4c9..6b202e3 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -795,7 +795,9 @@ struct dwc3_scratchpad_array {
* @usb3_phy: pointer to USB3 PHY
* @usb2_generic_phy: pointer to USB2 PHY
* @usb3_generic_phy: pointer to USB3 PHY
+ * @phys_ready: flag to indicate that PHYs are ready
* @ulpi: pointer to ulpi interface
+ * @ulpi_ready: flag to indicate that ULPI is initialized
* @isoch_delay: wValue from Set Isochronous Delay request;
* @u2sel: parameter from Set SEL request.
* @u2pel: parameter from Set SEL request.
@@ -893,7 +895,10 @@ struct dwc3 {
struct phy *usb2_generic_phy;
struct phy *usb3_generic_phy;
+ bool phys_ready;
+
struct ulpi *ulpi;
+ bool ulpi_ready;
void __iomem *regs;
size_t regs_size;
--
cheers,
-roger
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
This is a note to let you know that I've just added the patch titled
misc: mic/scif: fix copy-paste error in scif_create_remote_lookup
to my char-misc git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From 6484a677294aa5d08c0210f2f387ebb9be646115 Mon Sep 17 00:00:00 2001
From: YueHaibing <yuehaibing(a)huawei.com>
Date: Wed, 14 Nov 2018 01:57:03 +0000
Subject: misc: mic/scif: fix copy-paste error in scif_create_remote_lookup
gcc '-Wunused-but-set-variable' warning:
drivers/misc/mic/scif/scif_rma.c: In function 'scif_create_remote_lookup':
drivers/misc/mic/scif/scif_rma.c:373:25: warning:
variable 'vmalloc_num_pages' set but not used [-Wunused-but-set-variable]
'vmalloc_num_pages' should be used to determine if the address is
within the vmalloc range.
Fixes: ba612aa8b487 ("misc: mic: SCIF memory registration and unregistration")
Signed-off-by: YueHaibing <yuehaibing(a)huawei.com>
Cc: stable <stable(a)vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/misc/mic/scif/scif_rma.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/misc/mic/scif/scif_rma.c b/drivers/misc/mic/scif/scif_rma.c
index c824329f7012..0e4193cb08cf 100644
--- a/drivers/misc/mic/scif/scif_rma.c
+++ b/drivers/misc/mic/scif/scif_rma.c
@@ -416,7 +416,7 @@ static int scif_create_remote_lookup(struct scif_dev *remote_dev,
if (err)
goto error_window;
err = scif_map_page(&window->num_pages_lookup.lookup[j],
- vmalloc_dma_phys ?
+ vmalloc_num_pages ?
vmalloc_to_page(&window->num_pages[i]) :
virt_to_page(&window->num_pages[i]),
remote_dev);
--
2.19.2
+cc stable(a)vger.kernel.org
W dniu 2018-11-19 o 02:31, Mika Westerberg pisze:
> On Sun, Nov 18, 2018 at 07:13:18PM -0800, Krzysztof Olędzki wrote:
>> Hello Mika, Rafael, Greg,
>
> Hi,
>
>> Would it be possible to include the following two patches in 4.9-stable:
>> - "ACPI / watchdog: Prefer iTCO_wdt on Lenovo Z50-70"
>> - "ACPI / watchdog: Prefer iTCO_wdt always when WDAT table uses RTC SRAM"
>>
>> https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/com…
>> https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/com…
>>
>> Context: I just upgrade one of my servers from 4.4.161 to 4.9.137 and
>> run into a problem of not working RTC and watchdog. Adding these two
>> patches fixed the issue. No changes were necessary for them to be applied.
>
> I think the best way to get these included in stable trees is to send
> the commit ids with the above explanation to stable(a)vger.kernel.org.
Thank you Mika! I forgot how the process works. :/
The commits are:
a0a37862a4e1844793d39aca9ccb8fecbdcb8659
5a802a7a285c8877ca872e44eeb0f06afcb5212f
It also looks like the first patch is already in 4.14-stable, just not
in 4.9.
- a0a37862a4e1844793d39aca9ccb8fecbdcb8659 was included in 4.14.51:
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.51
However, it does not look like the 2nd one has been included in 4.14
yet. Would it be then possible to add
5a802a7a285c8877ca872e44eeb0f06afcb5212f to both 4.9-stable and 4.14-stable?
The impacted system is:
Dell Inc. PowerEdge T110 II/0PM2CW, BIOS 2.10.0 05/24/2018
Krzysztof
From: Dexuan Cui <decui(a)microsoft.com>
This is a longstanding issue: if the vmbus upper-layer drivers try to
consume too many GPADLs, the host may return with an error
0xC0000044 (STATUS_QUOTA_EXCEEDED), but currently we forget to check
the creation_status, and hence we can pass an invalid GPADL handle
into the OPEN_CHANNEL message, and get an error code 0xc0000225 in
open_info->response.open_result.status, and finally we hang in
vmbus_open() -> "goto error_free_info" -> vmbus_teardown_gpadl().
With this patch, we can exit gracefully on STATUS_QUOTA_EXCEEDED.
Cc: Stephen Hemminger <sthemmin(a)microsoft.com>
Cc: K. Y. Srinivasan <kys(a)microsoft.com>
Cc: Haiyang Zhang <haiyangz(a)microsoft.com>
Cc: stable(a)vger.kernel.org
Signed-off-by: Dexuan Cui <decui(a)microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys(a)microsoft.com>
---
drivers/hv/channel.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index f96a77b18bb9..ce0ba2062723 100644
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -516,6 +516,14 @@ int vmbus_establish_gpadl(struct vmbus_channel *channel, void *kbuffer,
}
wait_for_completion(&msginfo->waitevent);
+ if (msginfo->response.gpadl_created.creation_status != 0) {
+ pr_err("Failed to establish GPADL: err = 0x%x\n",
+ msginfo->response.gpadl_created.creation_status);
+
+ ret = -EDQUOT;
+ goto cleanup;
+ }
+
if (channel->rescind) {
ret = -ENODEV;
goto cleanup;
--
2.19.1
fast_coprocessor exception handler expects that the coprocessor owner
task never gets the "coprocessor disabled" exception for a coprocessor
that is marked as enabled in the thread_info::cpenable. If that happens
it will reload potentially outdated context from the thread_info
structure into the coprocessor registers.
Only call coprocessor_clear_cpenable from the coprocessor_release_all
if the latter is called for the current task.
Cc: stable(a)vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc(a)gmail.com>
---
arch/xtensa/kernel/process.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/xtensa/kernel/process.c b/arch/xtensa/kernel/process.c
index 3fa0c440f664..6c7c80106f60 100644
--- a/arch/xtensa/kernel/process.c
+++ b/arch/xtensa/kernel/process.c
@@ -87,7 +87,8 @@ void coprocessor_release_all(struct thread_info *ti)
}
ti->cpenable = cpenable;
- coprocessor_clear_cpenable();
+ if (ti == current_thread_info())
+ coprocessor_clear_cpenable();
preempt_enable();
}
--
2.11.0
From: Lyude <cpaul(a)redhat.com>
As observed with the latest ThinkPad docks, we unfortunately can't rely
on docks keeping us updated with hotplug events that happened while we
were suspended. On top of that, even if the number of connectors remains
the same between suspend and resume it's still not safe to assume that
there were no hotplugs, since a different monitor might have been
plugged into a port another monitor previously occupied. As such, we
need to go through all of the MST ports and check whether or not their
EDIDs have changed.
In addition to that, we also now return -EINVAL from
drm_dp_mst_topology_mgr_resume to indicate to callers that they need to
reset the MST connection, and that they can't rely on any other method
of reprobing.
Cc: stable(a)vger.kernel.org
Signed-off-by: Lyude <cpaul(a)redhat.com>
Signed-off-by: Juston Li <juston.li(a)intel.com>
---
drivers/gpu/drm/drm_dp_mst_topology.c | 94 ++++++++++++++++++++++++++-
1 file changed, 93 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 5ff1d79b86c4..88abebe52021 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -29,6 +29,7 @@
#include <linux/i2c.h>
#include <drm/drm_dp_mst_helper.h>
#include <drm/drmP.h>
+#include <drm/drm_edid.h>
#include <drm/drm_fixed.h>
#include <drm/drm_atomic.h>
@@ -2201,6 +2202,64 @@ void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr)
}
EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
+static bool drm_dp_mst_edids_changed(struct drm_dp_mst_topology_mgr *mgr,
+ struct drm_dp_mst_port *port)
+{
+ struct drm_device *dev;
+ struct drm_connector *connector;
+ struct drm_dp_mst_port *dport;
+ struct drm_dp_mst_branch *mstb;
+ struct edid *current_edid, *cached_edid;
+ bool ret = false;
+
+ port = drm_dp_get_validated_port_ref(mgr, port);
+ if (!port)
+ return false;
+
+ mstb = drm_dp_get_validated_mstb_ref(mgr, port->mstb);
+ if (mstb) {
+ list_for_each_entry(dport, &port->mstb->ports, next) {
+ ret = drm_dp_mst_edids_changed(mgr, dport);
+ if (ret)
+ break;
+ }
+
+ drm_dp_put_mst_branch_device(mstb);
+ if (ret)
+ goto out;
+ }
+
+ connector = port->connector;
+ if (!connector || !port->aux.ddc.algo)
+ goto out;
+
+ dev = connector->dev;
+ mutex_lock(&dev->mode_config.mutex);
+
+ current_edid = drm_get_edid(connector, &port->aux.ddc);
+ if (connector->edid_blob_ptr)
+ cached_edid = (void *)connector->edid_blob_ptr->data;
+ else
+ return false;
+
+ if ((current_edid && cached_edid && memcmp(current_edid, cached_edid,
+ sizeof(struct edid)) != 0) ||
+ (!current_edid && cached_edid) || (current_edid && !cached_edid)) {
+ ret = true;
+ DRM_DEBUG_KMS("EDID on %s changed, reprobing connectors\n",
+ connector->name);
+ }
+
+ mutex_unlock(&dev->mode_config.mutex);
+
+ kfree(current_edid);
+
+out:
+ drm_dp_put_port(port);
+
+ return ret;
+}
+
/**
* drm_dp_mst_topology_mgr_resume() - resume the MST manager
* @mgr: manager to resume
@@ -2210,9 +2269,15 @@ EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend);
*
* if the device fails this returns -1, and the driver should do
* a full MST reprobe, in case we were undocked.
+ *
+ * if the device can no longer be trusted, this returns -EINVAL
+ * and the driver should unconditionally disconnect and reconnect
+ * the dock.
*/
int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
{
+ struct drm_dp_mst_branch *mstb;
+ struct drm_dp_mst_port *port;
int ret = 0;
mutex_lock(&mgr->lock);
@@ -2246,8 +2311,35 @@ int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr)
drm_dp_check_mstb_guid(mgr->mst_primary, guid);
ret = 0;
- } else
+
+ /*
+ * Some hubs also forget to notify us of hotplugs that happened
+ * while we were in suspend, so we need to verify that the edid
+ * hasn't changed for any of the connectors. If it has been,
+ * we unfortunately can't rely on the dock updating us with
+ * hotplug events, so indicate we need a full reconnect.
+ */
+
+ /* MST's I2C helpers can't be used while holding this lock */
+ mutex_unlock(&mgr->lock);
+
+ mstb = drm_dp_get_validated_mstb_ref(mgr, mgr->mst_primary);
+ if (mstb) {
+ list_for_each_entry(port, &mstb->ports, next) {
+ if (drm_dp_mst_edids_changed(mgr, port)) {
+ ret = -EINVAL;
+ break;
+ }
+ }
+
+ drm_dp_put_mst_branch_device(mstb);
+ }
+ } else {
ret = -1;
+ mutex_unlock(&mgr->lock);
+ }
+
+ return ret;
out_unlock:
mutex_unlock(&mgr->lock);
--
2.17.2
coprocessor_flush_all may be called from a context of a thread that is
different from the thread being flushed. In that case contents of the
cpenable special register may not match ti->cpenable of the target
thread, resulting in unhandled coprocessor exception in the kernel
context.
Set cpenable special register to the ti->cpenable of the target register
for the duration of the flush and restore it afterwards.
This fixes the following crash caused by coprocessor register inspection
in native gdb:
(gdb) p/x $w0
Illegal instruction in kernel: sig: 9 [#1] PREEMPT
Call Trace:
___might_sleep+0x184/0x1a4
__might_sleep+0x41/0xac
exit_signals+0x14/0x218
do_exit+0xc9/0x8b8
die+0x99/0xa0
do_illegal_instruction+0x18/0x6c
common_exception+0x77/0x77
coprocessor_flush+0x16/0x3c
arch_ptrace+0x46c/0x674
sys_ptrace+0x2ce/0x3b4
system_call+0x54/0x80
common_exception+0x77/0x77
note: gdb[100] exited with preempt_count 1
Killed
Cc: stable(a)vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc(a)gmail.com>
---
arch/xtensa/kernel/process.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/xtensa/kernel/process.c b/arch/xtensa/kernel/process.c
index 9363629eb7cc..3fa0c440f664 100644
--- a/arch/xtensa/kernel/process.c
+++ b/arch/xtensa/kernel/process.c
@@ -94,18 +94,21 @@ void coprocessor_release_all(struct thread_info *ti)
void coprocessor_flush_all(struct thread_info *ti)
{
- unsigned long cpenable;
+ unsigned long cpenable, old_cpenable;
int i;
preempt_disable();
+ RSR_CPENABLE(old_cpenable);
cpenable = ti->cpenable;
+ WSR_CPENABLE(cpenable);
for (i = 0; i < XCHAL_CP_MAX; i++) {
if ((cpenable & 1) != 0 && coprocessor_owner[i] == ti)
coprocessor_flush(ti, i);
cpenable >>= 1;
}
+ WSR_CPENABLE(old_cpenable);
preempt_enable();
}
--
2.11.0
Hi Greg,
This was not marked for stable but seems it should be in stable.
And another commit which fixes it.
Please apply to your queue of 4.14-stable.
--
Regards
Sudip
> From: Sasha Levin <sashal(a)kernel.org>
> Sent: Monday, November 26, 2018 1:53 AM
> Hi,
>
> [This is an automated email]
>
> This commit has been processed because it contains a -stable tag.
> The stable tag indicates that it's relevant for the following trees: all
>
> The bot has tested the following trees: v4.19.4, v4.14.83, v4.9.140, v4.4.164,
> v3.18.126.
>
> v4.19.4: Build OK!
> v4.14.83: Build OK!
> v4.9.140: Build OK!
> v4.4.164: Failed to apply! Possible dependencies:
> v3.18.126: Failed to apply! Possible dependencies:
> How should we proceed with this patch?
>
> Sasha
Hi Sasha,
Please see the attached patch, which is a rebase for both v4.4.164 and v3.18.126.
Thanks,
--Dexuan
Jerry Zuo pointed out a rather obscure hotplugging issue that it seems I
accidentally introduced into DRM two years ago.
Pretend we have a topology like this:
|- DP-1: mst_primary
|- DP-4: active display
|- DP-5: disconnected
|- DP-6: active hub
|- DP-7: active display
|- DP-8: disconnected
|- DP-9: disconnected
If we unplug DP-6, the topology starting at DP-7 will be destroyed but
it's payloads will live on in DP-1's VCPI allocations and thus require
removal. However, this removal currently fails because
drm_dp_update_payload_part1() will (rightly so) try to validate the port
before accessing it, fail then abort. If we keep going, eventually we
run the MST hub out of bandwidth and all new allocations will start to
fail (or in my case; all new displays just start flickering a ton).
We could just teach drm_dp_update_payload_part1() not to drop the port
ref in this case, but then we also need to teach
drm_dp_destroy_payload_step1() to do the same thing, then hope no one
ever adds anything to the that requires a validated port reference in
drm_dp_destroy_connector_work(). Kind of sketchy.
So let's go with a more clever solution: any port that
drm_dp_destroy_connector_work() interacts with is guaranteed to still
exist in memory until we say so. While said port might not be valid we
don't really care: that's the whole reason we're destroying it in the
first place! So, teach drm_dp_get_validated_port_ref() to use the all
mighty current_work() function to avoid attempting to validate ports
from the context of mgr->destroy_connector_work. I can't see any
situation where this wouldn't be safe, and this avoids having to play
whack-a-mole in the future of trying to work around port validation.
Signed-off-by: Lyude Paul <lyude(a)redhat.com>
Fixes: 263efde31f97 ("drm/dp/mst: Get validated port ref in drm_dp_update_payload_part1()")
Reported-by: Jerry Zuo <Jerry.Zuo(a)amd.com>
Cc: Jerry Zuo <Jerry.Zuo(a)amd.com>
Cc: Harry Wentland <Harry.Wentland(a)amd.com>
Cc: <stable(a)vger.kernel.org> # v4.6+
---
drivers/gpu/drm/drm_dp_mst_topology.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 529414556962..08978ad72f33 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -1023,9 +1023,20 @@ static struct drm_dp_mst_port *drm_dp_mst_get_port_ref_locked(struct drm_dp_mst_
static struct drm_dp_mst_port *drm_dp_get_validated_port_ref(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port)
{
struct drm_dp_mst_port *rport = NULL;
+
mutex_lock(&mgr->lock);
- if (mgr->mst_primary)
- rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary, port);
+ /*
+ * Port may or may not be 'valid' but we don't care about that when
+ * destroying the port and we are guaranteed that the port pointer
+ * will be valid until we've finished
+ */
+ if (current_work() == &mgr->destroy_connector_work) {
+ kref_get(&port->kref);
+ rport = port;
+ } else if (mgr->mst_primary) {
+ rport = drm_dp_mst_get_port_ref_locked(mgr->mst_primary,
+ port);
+ }
mutex_unlock(&mgr->lock);
return rport;
}
--
2.19.1
The patch titled
Subject: userfaultfd: shmem: add i_size checks
has been added to the -mm tree. Its filename is
userfaultfd-shmem-add-i_size-checks.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/userfaultfd-shmem-add-i_size-check…
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/userfaultfd-shmem-add-i_size-check…
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Andrea Arcangeli <aarcange(a)redhat.com>
Subject: userfaultfd: shmem: add i_size checks
With MAP_SHARED: recheck the i_size after taking the PT lock, to serialize
against truncate with the PT lock. Delete the page from the pagecache if
the i_size_read check fails.
With MAP_PRIVATE: check the i_size after the PT lock before mapping
anonymous memory or zeropages into the MAP_PRIVATE shmem mapping.
A mostly irrelevant cleanup: like we do the delete_from_page_cache()
pagecache removal after dropping the PT lock, the PT lock is a spinlock so
drop it before the sleepable page lock.
Link: http://lkml.kernel.org/r/20181126173452.26955-5-aarcange@redhat.com
Fixes: 4c27fe4c4c84 ("userfaultfd: shmem: add shmem_mcopy_atomic_pte for userfaultfd support")
Signed-off-by: Andrea Arcangeli <aarcange(a)redhat.com>
Reviewed-by: Mike Rapoport <rppt(a)linux.ibm.com>
Reviewed-by: Hugh Dickins <hughd(a)google.com>
Reported-by: Jann Horn <jannh(a)google.com>
Cc: <stable(a)vger.kernel.org>
Cc: "Dr. David Alan Gilbert" <dgilbert(a)redhat.com>
Cc: Mike Kravetz <mike.kravetz(a)oracle.com>
Cc: Peter Xu <peterx(a)redhat.com>
Cc: stable(a)vger.kernel.org
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
--- a/mm/shmem.c~userfaultfd-shmem-add-i_size-checks
+++ a/mm/shmem.c
@@ -2216,6 +2216,7 @@ static int shmem_mfill_atomic_pte(struct
struct page *page;
pte_t _dst_pte, *dst_pte;
int ret;
+ pgoff_t offset, max_off;
ret = -ENOMEM;
if (!shmem_inode_acct_block(inode, 1))
@@ -2253,6 +2254,12 @@ static int shmem_mfill_atomic_pte(struct
__SetPageSwapBacked(page);
__SetPageUptodate(page);
+ ret = -EFAULT;
+ offset = linear_page_index(dst_vma, dst_addr);
+ max_off = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);
+ if (unlikely(offset >= max_off))
+ goto out_release;
+
ret = mem_cgroup_try_charge_delay(page, dst_mm, gfp, &memcg, false);
if (ret)
goto out_release;
@@ -2268,8 +2275,14 @@ static int shmem_mfill_atomic_pte(struct
if (dst_vma->vm_flags & VM_WRITE)
_dst_pte = pte_mkwrite(pte_mkdirty(_dst_pte));
- ret = -EEXIST;
dst_pte = pte_offset_map_lock(dst_mm, dst_pmd, dst_addr, &ptl);
+
+ ret = -EFAULT;
+ max_off = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);
+ if (unlikely(offset >= max_off))
+ goto out_release_uncharge_unlock;
+
+ ret = -EEXIST;
if (!pte_none(*dst_pte))
goto out_release_uncharge_unlock;
@@ -2287,13 +2300,14 @@ static int shmem_mfill_atomic_pte(struct
/* No need to invalidate - it was non-present before */
update_mmu_cache(dst_vma, dst_addr, dst_pte);
- unlock_page(page);
pte_unmap_unlock(dst_pte, ptl);
+ unlock_page(page);
ret = 0;
out:
return ret;
out_release_uncharge_unlock:
pte_unmap_unlock(dst_pte, ptl);
+ delete_from_page_cache(page);
out_release_uncharge:
mem_cgroup_cancel_charge(page, memcg, false);
out_release:
--- a/mm/userfaultfd.c~userfaultfd-shmem-add-i_size-checks
+++ a/mm/userfaultfd.c
@@ -33,6 +33,8 @@ static int mcopy_atomic_pte(struct mm_st
void *page_kaddr;
int ret;
struct page *page;
+ pgoff_t offset, max_off;
+ struct inode *inode;
if (!*pagep) {
ret = -ENOMEM;
@@ -73,8 +75,17 @@ static int mcopy_atomic_pte(struct mm_st
if (dst_vma->vm_flags & VM_WRITE)
_dst_pte = pte_mkwrite(pte_mkdirty(_dst_pte));
- ret = -EEXIST;
dst_pte = pte_offset_map_lock(dst_mm, dst_pmd, dst_addr, &ptl);
+ if (dst_vma->vm_file) {
+ /* the shmem MAP_PRIVATE case requires checking the i_size */
+ inode = dst_vma->vm_file->f_inode;
+ offset = linear_page_index(dst_vma, dst_addr);
+ max_off = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);
+ ret = -EFAULT;
+ if (unlikely(offset >= max_off))
+ goto out_release_uncharge_unlock;
+ }
+ ret = -EEXIST;
if (!pte_none(*dst_pte))
goto out_release_uncharge_unlock;
@@ -108,11 +119,22 @@ static int mfill_zeropage_pte(struct mm_
pte_t _dst_pte, *dst_pte;
spinlock_t *ptl;
int ret;
+ pgoff_t offset, max_off;
+ struct inode *inode;
_dst_pte = pte_mkspecial(pfn_pte(my_zero_pfn(dst_addr),
dst_vma->vm_page_prot));
- ret = -EEXIST;
dst_pte = pte_offset_map_lock(dst_mm, dst_pmd, dst_addr, &ptl);
+ if (dst_vma->vm_file) {
+ /* the shmem MAP_PRIVATE case requires checking the i_size */
+ inode = dst_vma->vm_file->f_inode;
+ offset = linear_page_index(dst_vma, dst_addr);
+ max_off = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);
+ ret = -EFAULT;
+ if (unlikely(offset >= max_off))
+ goto out_unlock;
+ }
+ ret = -EEXIST;
if (!pte_none(*dst_pte))
goto out_unlock;
set_pte_at(dst_mm, dst_addr, dst_pte, _dst_pte);
_
Patches currently in -mm which might be from aarcange(a)redhat.com are
userfaultfd-use-enoent-instead-of-efault-if-the-atomic-copy-user-fails.patch
userfaultfd-shmem-allocate-anonymous-memory-for-map_private-shmem.patch
userfaultfd-shmem-hugetlbfs-only-allow-to-register-vm_maywrite-vmas.patch
userfaultfd-shmem-add-i_size-checks.patch
userfaultfd-shmem-uffdio_copy-set-the-page-dirty-if-vm_write-is-not-set.patch
The patch titled
Subject: userfaultfd: shmem/hugetlbfs: only allow to register VM_MAYWRITE vmas
has been added to the -mm tree. Its filename is
userfaultfd-shmem-hugetlbfs-only-allow-to-register-vm_maywrite-vmas.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/userfaultfd-shmem-hugetlbfs-only-a…
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/userfaultfd-shmem-hugetlbfs-only-a…
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Andrea Arcangeli <aarcange(a)redhat.com>
Subject: userfaultfd: shmem/hugetlbfs: only allow to register VM_MAYWRITE vmas
After the VMA to register the uffd onto is found, check that it has
VM_MAYWRITE set before allowing registration. This way we inherit all
common code checks before allowing to fill file holes in shmem and
hugetlbfs with UFFDIO_COPY.
The userfaultfd memory model is not applicable for readonly files unless
it's a MAP_PRIVATE.
Link: http://lkml.kernel.org/r/20181126173452.26955-4-aarcange@redhat.com
Fixes: ff62a3421044 ("hugetlb: implement memfd sealing")
Signed-off-by: Andrea Arcangeli <aarcange(a)redhat.com>
Reviewed-by: Mike Rapoport <rppt(a)linux.ibm.com>
Reviewed-by: Hugh Dickins <hughd(a)google.com>
Reported-by: Jann Horn <jannh(a)google.com>
Fixes: 4c27fe4c4c84 ("userfaultfd: shmem: add shmem_mcopy_atomic_pte for userfaultfd support")
Cc: <stable(a)vger.kernel.org>
Cc: "Dr. David Alan Gilbert" <dgilbert(a)redhat.com>
Cc: Mike Kravetz <mike.kravetz(a)oracle.com>
Cc: Peter Xu <peterx(a)redhat.com>
Cc: stable(a)vger.kernel.org
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
--- a/fs/userfaultfd.c~userfaultfd-shmem-hugetlbfs-only-allow-to-register-vm_maywrite-vmas
+++ a/fs/userfaultfd.c
@@ -1361,6 +1361,19 @@ static int userfaultfd_register(struct u
ret = -EINVAL;
if (!vma_can_userfault(cur))
goto out_unlock;
+
+ /*
+ * UFFDIO_COPY will fill file holes even without
+ * PROT_WRITE. This check enforces that if this is a
+ * MAP_SHARED, the process has write permission to the backing
+ * file. If VM_MAYWRITE is set it also enforces that on a
+ * MAP_SHARED vma: there is no F_WRITE_SEAL and no further
+ * F_WRITE_SEAL can be taken until the vma is destroyed.
+ */
+ ret = -EPERM;
+ if (unlikely(!(cur->vm_flags & VM_MAYWRITE)))
+ goto out_unlock;
+
/*
* If this vma contains ending address, and huge pages
* check alignment.
@@ -1406,6 +1419,7 @@ static int userfaultfd_register(struct u
BUG_ON(!vma_can_userfault(vma));
BUG_ON(vma->vm_userfaultfd_ctx.ctx &&
vma->vm_userfaultfd_ctx.ctx != ctx);
+ WARN_ON(!(vma->vm_flags & VM_MAYWRITE));
/*
* Nothing to do: this vma is already registered into this
@@ -1552,6 +1566,7 @@ static int userfaultfd_unregister(struct
cond_resched();
BUG_ON(!vma_can_userfault(vma));
+ WARN_ON(!(vma->vm_flags & VM_MAYWRITE));
/*
* Nothing to do: this vma is already registered into this
--- a/mm/userfaultfd.c~userfaultfd-shmem-hugetlbfs-only-allow-to-register-vm_maywrite-vmas
+++ a/mm/userfaultfd.c
@@ -205,8 +205,9 @@ retry:
if (!dst_vma || !is_vm_hugetlb_page(dst_vma))
goto out_unlock;
/*
- * Only allow __mcopy_atomic_hugetlb on userfaultfd
- * registered ranges.
+ * Check the vma is registered in uffd, this is
+ * required to enforce the VM_MAYWRITE check done at
+ * uffd registration time.
*/
if (!dst_vma->vm_userfaultfd_ctx.ctx)
goto out_unlock;
@@ -459,13 +460,9 @@ retry:
if (!dst_vma)
goto out_unlock;
/*
- * Be strict and only allow __mcopy_atomic on userfaultfd
- * registered ranges to prevent userland errors going
- * unnoticed. As far as the VM consistency is concerned, it
- * would be perfectly safe to remove this check, but there's
- * no useful usage for __mcopy_atomic ouside of userfaultfd
- * registered ranges. This is after all why these are ioctls
- * belonging to the userfaultfd and not syscalls.
+ * Check the vma is registered in uffd, this is required to
+ * enforce the VM_MAYWRITE check done at uffd registration
+ * time.
*/
if (!dst_vma->vm_userfaultfd_ctx.ctx)
goto out_unlock;
_
Patches currently in -mm which might be from aarcange(a)redhat.com are
userfaultfd-use-enoent-instead-of-efault-if-the-atomic-copy-user-fails.patch
userfaultfd-shmem-allocate-anonymous-memory-for-map_private-shmem.patch
userfaultfd-shmem-hugetlbfs-only-allow-to-register-vm_maywrite-vmas.patch
userfaultfd-shmem-add-i_size-checks.patch
userfaultfd-shmem-uffdio_copy-set-the-page-dirty-if-vm_write-is-not-set.patch
The patch titled
Subject: userfaultfd: shmem: allocate anonymous memory for MAP_PRIVATE shmem
has been added to the -mm tree. Its filename is
userfaultfd-shmem-allocate-anonymous-memory-for-map_private-shmem.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/userfaultfd-shmem-allocate-anonymo…
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/userfaultfd-shmem-allocate-anonymo…
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Andrea Arcangeli <aarcange(a)redhat.com>
Subject: userfaultfd: shmem: allocate anonymous memory for MAP_PRIVATE shmem
Userfaultfd did not create private memory when UFFDIO_COPY was invoked on
a MAP_PRIVATE shmem mapping. Instead it wrote to the shmem file, even
when that had not been opened for writing. Though, fortunately, that
could only happen where there was a hole in the file.
Fix the shmem-backed implementation of UFFDIO_COPY to create private
memory for MAP_PRIVATE mappings. The hugetlbfs-backed implementation was
already correct.
This change is visible to userland, if userfaultfd has been used in
unintended ways: so it introduces a small risk of incompatibility, but is
necessary in order to respect file permissions.
An app that uses UFFDIO_COPY for anything like postcopy live migration
won't notice the difference, and in fact it'll run faster because there
will be no copy-on-write and memory waste in the tmpfs pagecache anymore.
Userfaults on MAP_PRIVATE shmem keep triggering only on file holes like
before.
The real zeropage can also be built on a MAP_PRIVATE shmem mapping through
UFFDIO_ZEROPAGE and that's safe because the zeropage pte is never dirty,
in turn even an mprotect upgrading the vma permission from PROT_READ to
PROT_READ|PROT_WRITE won't make the zeropage pte writable.
Link: http://lkml.kernel.org/r/20181126173452.26955-3-aarcange@redhat.com
Fixes: 4c27fe4c4c84 ("userfaultfd: shmem: add shmem_mcopy_atomic_pte for userfaultfd support")
Signed-off-by: Andrea Arcangeli <aarcange(a)redhat.com>
Reported-by: Mike Rapoport <rppt(a)linux.ibm.com>
Reviewed-by: Hugh Dickins <hughd(a)google.com>
Cc: <stable(a)vger.kernel.org>
Cc: "Dr. David Alan Gilbert" <dgilbert(a)redhat.com>
Cc: Jann Horn <jannh(a)google.com>
Cc: Mike Kravetz <mike.kravetz(a)oracle.com>
Cc: Peter Xu <peterx(a)redhat.com>
Cc: stable(a)vger.kernel.org
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
--- a/mm/userfaultfd.c~userfaultfd-shmem-allocate-anonymous-memory-for-map_private-shmem
+++ a/mm/userfaultfd.c
@@ -380,7 +380,17 @@ static __always_inline ssize_t mfill_ato
{
ssize_t err;
- if (vma_is_anonymous(dst_vma)) {
+ /*
+ * The normal page fault path for a shmem will invoke the
+ * fault, fill the hole in the file and COW it right away. The
+ * result generates plain anonymous memory. So when we are
+ * asked to fill an hole in a MAP_PRIVATE shmem mapping, we'll
+ * generate anonymous memory directly without actually filling
+ * the hole. For the MAP_PRIVATE case the robustness check
+ * only happens in the pagetable (to verify it's still none)
+ * and not in the radix tree.
+ */
+ if (!(dst_vma->vm_flags & VM_SHARED)) {
if (!zeropage)
err = mcopy_atomic_pte(dst_mm, dst_pmd, dst_vma,
dst_addr, src_addr, page);
@@ -489,7 +499,8 @@ retry:
* dst_vma.
*/
err = -ENOMEM;
- if (vma_is_anonymous(dst_vma) && unlikely(anon_vma_prepare(dst_vma)))
+ if (!(dst_vma->vm_flags & VM_SHARED) &&
+ unlikely(anon_vma_prepare(dst_vma)))
goto out_unlock;
while (src_addr < src_start + len) {
_
Patches currently in -mm which might be from aarcange(a)redhat.com are
userfaultfd-use-enoent-instead-of-efault-if-the-atomic-copy-user-fails.patch
userfaultfd-shmem-allocate-anonymous-memory-for-map_private-shmem.patch
userfaultfd-shmem-hugetlbfs-only-allow-to-register-vm_maywrite-vmas.patch
userfaultfd-shmem-add-i_size-checks.patch
userfaultfd-shmem-uffdio_copy-set-the-page-dirty-if-vm_write-is-not-set.patch
The patch titled
Subject: userfaultfd: use ENOENT instead of EFAULT if the atomic copy user fails
has been added to the -mm tree. Its filename is
userfaultfd-use-enoent-instead-of-efault-if-the-atomic-copy-user-fails.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/userfaultfd-use-enoent-instead-of-…
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/userfaultfd-use-enoent-instead-of-…
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Andrea Arcangeli <aarcange(a)redhat.com>
Subject: userfaultfd: use ENOENT instead of EFAULT if the atomic copy user fails
Patch series "userfaultfd shmem updates".
Jann found two bugs in the userfaultfd shmem MAP_SHARED backend: the lack
of the VM_MAYWRITE check and the lack of i_size checks.
Then looking into the above we also fixed the MAP_PRIVATE case.
Hugh by source review also found a data loss source if UFFDIO_COPY is used
on shmem MAP_SHARED PROT_READ mappings (the production usages incidentally
run with PROT_READ|PROT_WRITE, so the data loss couldn't happen in those
production usages like with QEMU).
The whole patchset is marked for stable.
We verified QEMU postcopy live migration with guest running on shmem
MAP_PRIVATE run as well as before after the fix of shmem MAP_PRIVATE.
Regardless if it's shmem or hugetlbfs or MAP_PRIVATE or MAP_SHARED, QEMU
unconditionally invokes a punch hole if the guest mapping is filebacked
and a MADV_DONTNEED too (needed to get rid of the MAP_PRIVATE COWs and for
the anon backend).
This patch (of 5):
We internally used EFAULT to communicate with the caller, switch to
ENOENT, so EFAULT can be used as a non internal retval.
Link: http://lkml.kernel.org/r/20181126173452.26955-2-aarcange@redhat.com
Fixes: 4c27fe4c4c84 ("userfaultfd: shmem: add shmem_mcopy_atomic_pte for userfaultfd support")
Signed-off-by: Andrea Arcangeli <aarcange(a)redhat.com>
Reviewed-by: Mike Rapoport <rppt(a)linux.ibm.com>
Reviewed-by: Hugh Dickins <hughd(a)google.com>
Cc: Mike Kravetz <mike.kravetz(a)oracle.com>
Cc: Jann Horn <jannh(a)google.com>
Cc: Peter Xu <peterx(a)redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert(a)redhat.com>
Cc: <stable(a)vger.kernel.org>
Cc: stable(a)vger.kernel.org
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
--- a/mm/hugetlb.c~userfaultfd-use-enoent-instead-of-efault-if-the-atomic-copy-user-fails
+++ a/mm/hugetlb.c
@@ -4080,7 +4080,7 @@ int hugetlb_mcopy_atomic_pte(struct mm_s
/* fallback to copy_from_user outside mmap_sem */
if (unlikely(ret)) {
- ret = -EFAULT;
+ ret = -ENOENT;
*pagep = page;
/* don't free the page */
goto out;
--- a/mm/shmem.c~userfaultfd-use-enoent-instead-of-efault-if-the-atomic-copy-user-fails
+++ a/mm/shmem.c
@@ -2238,7 +2238,7 @@ static int shmem_mfill_atomic_pte(struct
*pagep = page;
shmem_inode_unacct_blocks(inode, 1);
/* don't free the page */
- return -EFAULT;
+ return -ENOENT;
}
} else { /* mfill_zeropage_atomic */
clear_highpage(page);
--- a/mm/userfaultfd.c~userfaultfd-use-enoent-instead-of-efault-if-the-atomic-copy-user-fails
+++ a/mm/userfaultfd.c
@@ -48,7 +48,7 @@ static int mcopy_atomic_pte(struct mm_st
/* fallback to copy_from_user outside mmap_sem */
if (unlikely(ret)) {
- ret = -EFAULT;
+ ret = -ENOENT;
*pagep = page;
/* don't free the page */
goto out;
@@ -274,7 +274,7 @@ retry:
cond_resched();
- if (unlikely(err == -EFAULT)) {
+ if (unlikely(err == -ENOENT)) {
up_read(&dst_mm->mmap_sem);
BUG_ON(!page);
@@ -530,7 +530,7 @@ retry:
src_addr, &page, zeropage);
cond_resched();
- if (unlikely(err == -EFAULT)) {
+ if (unlikely(err == -ENOENT)) {
void *page_kaddr;
up_read(&dst_mm->mmap_sem);
_
Patches currently in -mm which might be from aarcange(a)redhat.com are
userfaultfd-use-enoent-instead-of-efault-if-the-atomic-copy-user-fails.patch
userfaultfd-shmem-allocate-anonymous-memory-for-map_private-shmem.patch
userfaultfd-shmem-hugetlbfs-only-allow-to-register-vm_maywrite-vmas.patch
userfaultfd-shmem-add-i_size-checks.patch
userfaultfd-shmem-uffdio_copy-set-the-page-dirty-if-vm_write-is-not-set.patch
This is a note to let you know that I've just added the patch titled
binder: fix race that allows malicious free of live buffer
to my char-misc git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From 7bada55ab50697861eee6bb7d60b41e68a961a9c Mon Sep 17 00:00:00 2001
From: Todd Kjos <tkjos(a)android.com>
Date: Tue, 6 Nov 2018 15:55:32 -0800
Subject: binder: fix race that allows malicious free of live buffer
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Malicious code can attempt to free buffers using the BC_FREE_BUFFER
ioctl to binder. There are protections against a user freeing a buffer
while in use by the kernel, however there was a window where
BC_FREE_BUFFER could be used to free a recently allocated buffer that
was not completely initialized. This resulted in a use-after-free
detected by KASAN with a malicious test program.
This window is closed by setting the buffer's allow_user_free attribute
to 0 when the buffer is allocated or when the user has previously freed
it instead of waiting for the caller to set it. The problem was that
when the struct buffer was recycled, allow_user_free was stale and set
to 1 allowing a free to go through.
Signed-off-by: Todd Kjos <tkjos(a)google.com>
Acked-by: Arve Hjønnevåg <arve(a)android.com>
Cc: stable <stable(a)vger.kernel.org> # 4.14
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/android/binder.c | 21 ++++++++++++---------
drivers/android/binder_alloc.c | 16 ++++++----------
drivers/android/binder_alloc.h | 3 +--
3 files changed, 19 insertions(+), 21 deletions(-)
diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index cb30a524d16d..9f1000d2a40c 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -2974,7 +2974,6 @@ static void binder_transaction(struct binder_proc *proc,
t->buffer = NULL;
goto err_binder_alloc_buf_failed;
}
- t->buffer->allow_user_free = 0;
t->buffer->debug_id = t->debug_id;
t->buffer->transaction = t;
t->buffer->target_node = target_node;
@@ -3510,14 +3509,18 @@ static int binder_thread_write(struct binder_proc *proc,
buffer = binder_alloc_prepare_to_free(&proc->alloc,
data_ptr);
- if (buffer == NULL) {
- binder_user_error("%d:%d BC_FREE_BUFFER u%016llx no match\n",
- proc->pid, thread->pid, (u64)data_ptr);
- break;
- }
- if (!buffer->allow_user_free) {
- binder_user_error("%d:%d BC_FREE_BUFFER u%016llx matched unreturned buffer\n",
- proc->pid, thread->pid, (u64)data_ptr);
+ if (IS_ERR_OR_NULL(buffer)) {
+ if (PTR_ERR(buffer) == -EPERM) {
+ binder_user_error(
+ "%d:%d BC_FREE_BUFFER u%016llx matched unreturned or currently freeing buffer\n",
+ proc->pid, thread->pid,
+ (u64)data_ptr);
+ } else {
+ binder_user_error(
+ "%d:%d BC_FREE_BUFFER u%016llx no match\n",
+ proc->pid, thread->pid,
+ (u64)data_ptr);
+ }
break;
}
binder_debug(BINDER_DEBUG_FREE_BUFFER,
diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index 64fd96eada31..030c98f35cca 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -151,16 +151,12 @@ static struct binder_buffer *binder_alloc_prepare_to_free_locked(
else {
/*
* Guard against user threads attempting to
- * free the buffer twice
+ * free the buffer when in use by kernel or
+ * after it's already been freed.
*/
- if (buffer->free_in_progress) {
- binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
- "%d:%d FREE_BUFFER u%016llx user freed buffer twice\n",
- alloc->pid, current->pid,
- (u64)user_ptr);
- return NULL;
- }
- buffer->free_in_progress = 1;
+ if (!buffer->allow_user_free)
+ return ERR_PTR(-EPERM);
+ buffer->allow_user_free = 0;
return buffer;
}
}
@@ -500,7 +496,7 @@ static struct binder_buffer *binder_alloc_new_buf_locked(
rb_erase(best_fit, &alloc->free_buffers);
buffer->free = 0;
- buffer->free_in_progress = 0;
+ buffer->allow_user_free = 0;
binder_insert_allocated_buffer_locked(alloc, buffer);
binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
"%d: binder_alloc_buf size %zd got %pK\n",
diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h
index 9ef64e563856..fb3238c74c8a 100644
--- a/drivers/android/binder_alloc.h
+++ b/drivers/android/binder_alloc.h
@@ -50,8 +50,7 @@ struct binder_buffer {
unsigned free:1;
unsigned allow_user_free:1;
unsigned async_transaction:1;
- unsigned free_in_progress:1;
- unsigned debug_id:28;
+ unsigned debug_id:29;
struct binder_transaction *transaction;
--
2.19.2
Hello,
We ran automated tests on a recent commit from this kernel tree:
Kernel repo: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
Commit: be4bbf9fbca5 Linux 4.19.5-rc1
The results of these automated tests are provided below.
Overall result: PASSED
Patch merge: OK
Compile: OK
Kernel tests: OK
Please reply to this email if you have any questions about the tests that we
ran or if you have any suggestions on how to make future tests more effective.
,-. ,-.
( C ) ( K ) Continuous
`-',-.`-' Kernel
( I ) Integration
`-'
______________________________________________________________________________
Compile testing
---------------
We compiled the kernel for 2 architectures:
aarch64:
make options: make INSTALL_MOD_STRIP=1 -j56 targz-pkg
configuration: https://artifacts.cki-project.org/builds/aarch64/be4bbf9fbca5867a720f1f53c7…
x86_64:
make options: make INSTALL_MOD_STRIP=1 -j56 targz-pkg
configuration: https://artifacts.cki-project.org/builds/x86_64/be4bbf9fbca5867a720f1f53c7d…
Hardware testing
----------------
We booted each kernel and ran the following tests:
arm64:
/distribution/kpkginstall (boot test)
LTP lite - release 20180515
xfstests: ext4
xfstests: xfs
/kernel/misc/amtu
x86_64:
/distribution/kpkginstall (boot test)
LTP lite - release 20180515
xfstests: ext4
xfstests: xfs
/kernel/misc/amtu
Hi Greg,
Please apply commit 2278446e2b7c ("xhci: Fix USB3 NULL pointer dereference
at logical disconnect.") to v4.4.y. It fixes commit 44a182b9d177 ("xhci:
Fix use-after-free in xhci_free_virt_device"), which was applied to v4.4.y.
Thanks,
Guenter