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-rw-r--r--Documentation/ABI/testing/sysfs-class-led-trigger-pattern4
-rw-r--r--Documentation/admin-guide/cgroup-v2.rst8
-rw-r--r--Documentation/admin-guide/kernel-parameters.txt8
-rw-r--r--Documentation/admin-guide/pm/cpufreq.rst2
-rw-r--r--Documentation/admin-guide/security-bugs.rst21
-rw-r--r--Documentation/cpu-freq/cpufreq-stats.txt8
-rw-r--r--Documentation/crypto/asymmetric-keys.txt26
-rw-r--r--Documentation/devicetree/bindings/arm/cpu-capacity.txt8
-rw-r--r--Documentation/devicetree/bindings/arm/shmobile.txt2
-rw-r--r--Documentation/devicetree/bindings/cpufreq/arm_big_little_dt.txt65
-rw-r--r--Documentation/devicetree/bindings/display/panel/innolux,p120zdg-bf1.txt (renamed from Documentation/devicetree/bindings/display/panel/innolux,tv123wam.txt)8
-rw-r--r--Documentation/devicetree/bindings/display/panel/simple-panel.txt3
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-imx-lpi2c.txt1
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-omap.txt8
-rw-r--r--Documentation/devicetree/bindings/net/can/holt_hi311x.txt2
-rw-r--r--Documentation/devicetree/bindings/net/can/rcar_can.txt28
-rw-r--r--Documentation/devicetree/bindings/net/dsa/dsa.txt2
-rw-r--r--Documentation/devicetree/bindings/pwm/pwm-tiecap.txt1
-rw-r--r--Documentation/devicetree/bindings/pwm/renesas,pwm-rcar.txt4
-rw-r--r--Documentation/devicetree/bindings/pwm/renesas,tpu-pwm.txt10
-rw-r--r--Documentation/devicetree/bindings/timer/csky,gx6605s-timer.txt42
-rw-r--r--Documentation/devicetree/bindings/timer/csky,mptimer.txt42
-rw-r--r--Documentation/filesystems/overlayfs.txt6
-rw-r--r--Documentation/filesystems/porting5
-rw-r--r--Documentation/filesystems/ubifs-authentication.md426
-rw-r--r--Documentation/filesystems/ubifs.txt7
-rw-r--r--Documentation/filesystems/vfs.txt22
-rw-r--r--Documentation/i2c/busses/i2c-nvidia-gpu18
-rw-r--r--Documentation/kbuild/makefiles.txt15
-rw-r--r--Documentation/media/uapi/v4l/dev-meta.rst2
-rw-r--r--Documentation/media/uapi/v4l/vidioc-g-fmt.rst5
-rw-r--r--Documentation/networking/ice.rst2
-rw-r--r--Documentation/networking/ip-sysctl.txt11
-rw-r--r--Documentation/networking/rxrpc.txt17
-rw-r--r--Documentation/process/index.rst1
-rw-r--r--Documentation/process/programming-language.rst45
-rw-r--r--Documentation/security/keys/core.rst217
-rw-r--r--Documentation/security/self-protection.rst10
-rw-r--r--Documentation/sysctl/kernel.txt18
-rw-r--r--Documentation/x86/x86_64/mm.txt37
-rw-r--r--Documentation/x86/zero-page.txt2
41 files changed, 1002 insertions, 167 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-led-trigger-pattern b/Documentation/ABI/testing/sysfs-class-led-trigger-pattern
index fb3d1e03b881..1e5d172e0646 100644
--- a/Documentation/ABI/testing/sysfs-class-led-trigger-pattern
+++ b/Documentation/ABI/testing/sysfs-class-led-trigger-pattern
@@ -37,8 +37,8 @@ Description:
0-| / \/ \/
+---0----1----2----3----4----5----6------------> time (s)
- 2. To make the LED go instantly from one brigntess value to another,
- we should use use zero-time lengths (the brightness must be same as
+ 2. To make the LED go instantly from one brightness value to another,
+ we should use zero-time lengths (the brightness must be same as
the previous tuple's). So the format should be:
"brightness_1 duration_1 brightness_1 0 brightness_2 duration_2
brightness_2 0 ...". For example:
diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst
index 8384c681a4b2..476722b7b636 100644
--- a/Documentation/admin-guide/cgroup-v2.rst
+++ b/Documentation/admin-guide/cgroup-v2.rst
@@ -1879,10 +1879,8 @@ following two functions.
wbc_init_bio(@wbc, @bio)
Should be called for each bio carrying writeback data and
- associates the bio with the inode's owner cgroup and the
- corresponding request queue. This must be called after
- a queue (device) has been associated with the bio and
- before submission.
+ associates the bio with the inode's owner cgroup. Can be
+ called anytime between bio allocation and submission.
wbc_account_io(@wbc, @page, @bytes)
Should be called for each data segment being written out.
@@ -1901,7 +1899,7 @@ the configuration, the bio may be executed at a lower priority and if
the writeback session is holding shared resources, e.g. a journal
entry, may lead to priority inversion. There is no one easy solution
for the problem. Filesystems can try to work around specific problem
-cases by skipping wbc_init_bio() or using bio_associate_create_blkg()
+cases by skipping wbc_init_bio() or using bio_associate_blkcg()
directly.
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index b90fe3b6bc6c..19f4423e70d9 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1068,7 +1068,7 @@
earlyprintk=serial[,0x...[,baudrate]]
earlyprintk=ttySn[,baudrate]
earlyprintk=dbgp[debugController#]
- earlyprintk=pciserial,bus:device.function[,baudrate]
+ earlyprintk=pciserial[,force],bus:device.function[,baudrate]
earlyprintk=xdbc[xhciController#]
earlyprintk is useful when the kernel crashes before
@@ -1100,6 +1100,10 @@
The sclp output can only be used on s390.
+ The optional "force" to "pciserial" enables use of a
+ PCI device even when its classcode is not of the
+ UART class.
+
edac_report= [HW,EDAC] Control how to report EDAC event
Format: {"on" | "off" | "force"}
on: enable EDAC to report H/W event. May be overridden
@@ -4709,6 +4713,8 @@
prevent spurious wakeup);
n = USB_QUIRK_DELAY_CTRL_MSG (Device needs a
pause after every control message);
+ o = USB_QUIRK_HUB_SLOW_RESET (Hub needs extra
+ delay after resetting its port);
Example: quirks=0781:5580:bk,0a5c:5834:gij
usbhid.mousepoll=
diff --git a/Documentation/admin-guide/pm/cpufreq.rst b/Documentation/admin-guide/pm/cpufreq.rst
index 47153e64dfb5..7eca9026a9ed 100644
--- a/Documentation/admin-guide/pm/cpufreq.rst
+++ b/Documentation/admin-guide/pm/cpufreq.rst
@@ -150,7 +150,7 @@ data structures necessary to handle the given policy and, possibly, to add
a governor ``sysfs`` interface to it. Next, the governor is started by
invoking its ``->start()`` callback.
-That callback it expected to register per-CPU utilization update callbacks for
+That callback is expected to register per-CPU utilization update callbacks for
all of the online CPUs belonging to the given policy with the CPU scheduler.
The utilization update callbacks will be invoked by the CPU scheduler on
important events, like task enqueue and dequeue, on every iteration of the
diff --git a/Documentation/admin-guide/security-bugs.rst b/Documentation/admin-guide/security-bugs.rst
index 164bf71149fd..30187d49dc2c 100644
--- a/Documentation/admin-guide/security-bugs.rst
+++ b/Documentation/admin-guide/security-bugs.rst
@@ -32,16 +32,17 @@ Disclosure and embargoed information
The security list is not a disclosure channel. For that, see Coordination
below.
-Once a robust fix has been developed, our preference is to release the
-fix in a timely fashion, treating it no differently than any of the other
-thousands of changes and fixes the Linux kernel project releases every
-month.
-
-However, at the request of the reporter, we will postpone releasing the
-fix for up to 5 business days after the date of the report or after the
-embargo has lifted; whichever comes first. The only exception to that
-rule is if the bug is publicly known, in which case the preference is to
-release the fix as soon as it's available.
+Once a robust fix has been developed, the release process starts. Fixes
+for publicly known bugs are released immediately.
+
+Although our preference is to release fixes for publicly undisclosed bugs
+as soon as they become available, this may be postponed at the request of
+the reporter or an affected party for up to 7 calendar days from the start
+of the release process, with an exceptional extension to 14 calendar days
+if it is agreed that the criticality of the bug requires more time. The
+only valid reason for deferring the publication of a fix is to accommodate
+the logistics of QA and large scale rollouts which require release
+coordination.
Whilst embargoed information may be shared with trusted individuals in
order to develop a fix, such information will not be published alongside
diff --git a/Documentation/cpu-freq/cpufreq-stats.txt b/Documentation/cpu-freq/cpufreq-stats.txt
index a873855c811d..14378cecb172 100644
--- a/Documentation/cpu-freq/cpufreq-stats.txt
+++ b/Documentation/cpu-freq/cpufreq-stats.txt
@@ -86,9 +86,11 @@ transitions.
This will give a fine grained information about all the CPU frequency
transitions. The cat output here is a two dimensional matrix, where an entry
<i,j> (row i, column j) represents the count of number of transitions from
-Freq_i to Freq_j. Freq_i is in descending order with increasing rows and
-Freq_j is in descending order with increasing columns. The output here also
-contains the actual freq values for each row and column for better readability.
+Freq_i to Freq_j. Freq_i rows and Freq_j columns follow the sorting order in
+which the driver has provided the frequency table initially to the cpufreq core
+and so can be sorted (ascending or descending) or unsorted. The output here
+also contains the actual freq values for each row and column for better
+readability.
If the transition table is bigger than PAGE_SIZE, reading this will
return an -EFBIG error.
diff --git a/Documentation/crypto/asymmetric-keys.txt b/Documentation/crypto/asymmetric-keys.txt
index 5969bf42562a..8763866b11cf 100644
--- a/Documentation/crypto/asymmetric-keys.txt
+++ b/Documentation/crypto/asymmetric-keys.txt
@@ -183,6 +183,10 @@ and looks like the following:
void (*describe)(const struct key *key, struct seq_file *m);
void (*destroy)(void *payload);
+ int (*query)(const struct kernel_pkey_params *params,
+ struct kernel_pkey_query *info);
+ int (*eds_op)(struct kernel_pkey_params *params,
+ const void *in, void *out);
int (*verify_signature)(const struct key *key,
const struct public_key_signature *sig);
};
@@ -207,12 +211,22 @@ There are a number of operations defined by the subtype:
asymmetric key will look after freeing the fingerprint and releasing the
reference on the subtype module.
- (3) verify_signature().
+ (3) query().
- Optional. These are the entry points for the key usage operations.
- Currently there is only the one defined. If not set, the caller will be
- given -ENOTSUPP. The subtype may do anything it likes to implement an
- operation, including offloading to hardware.
+ Mandatory. This is a function for querying the capabilities of a key.
+
+ (4) eds_op().
+
+ Optional. This is the entry point for the encryption, decryption and
+ signature creation operations (which are distinguished by the operation ID
+ in the parameter struct). The subtype may do anything it likes to
+ implement an operation, including offloading to hardware.
+
+ (5) verify_signature().
+
+ Optional. This is the entry point for signature verification. The
+ subtype may do anything it likes to implement an operation, including
+ offloading to hardware.
==========================
@@ -234,6 +248,8 @@ Examples of blob formats for which parsers could be implemented include:
- X.509 ASN.1 stream.
- Pointer to TPM key.
- Pointer to UEFI key.
+ - PKCS#8 private key [RFC 5208].
+ - PKCS#5 encrypted private key [RFC 2898].
During key instantiation each parser in the list is tried until one doesn't
return -EBADMSG.
diff --git a/Documentation/devicetree/bindings/arm/cpu-capacity.txt b/Documentation/devicetree/bindings/arm/cpu-capacity.txt
index 9b5685a1d15d..84262cdb8d29 100644
--- a/Documentation/devicetree/bindings/arm/cpu-capacity.txt
+++ b/Documentation/devicetree/bindings/arm/cpu-capacity.txt
@@ -59,9 +59,11 @@ mhz values (normalized w.r.t. the highest value found while parsing the DT).
===========================================
Example 1 (ARM 64-bit, 6-cpu system, two clusters):
-capacities-dmips-mhz are scaled w.r.t. 1024 (cpu@0 and cpu@1)
-supposing cluster0@max-freq=1100 and custer1@max-freq=850,
-final capacities are 1024 for cluster0 and 446 for cluster1
+The capacities-dmips-mhz or DMIPS/MHz values (scaled to 1024)
+are 1024 and 578 for cluster0 and cluster1. Further normalization
+is done by the operating system based on cluster0@max-freq=1100 and
+custer1@max-freq=850, final capacities are 1024 for cluster0 and
+446 for cluster1 (576*850/1100).
cpus {
#address-cells = <2>;
diff --git a/Documentation/devicetree/bindings/arm/shmobile.txt b/Documentation/devicetree/bindings/arm/shmobile.txt
index f5e0f82fd503..58c4256d37a3 100644
--- a/Documentation/devicetree/bindings/arm/shmobile.txt
+++ b/Documentation/devicetree/bindings/arm/shmobile.txt
@@ -27,7 +27,7 @@ SoCs:
compatible = "renesas,r8a77470"
- RZ/G2M (R8A774A1)
compatible = "renesas,r8a774a1"
- - RZ/G2E (RA8774C0)
+ - RZ/G2E (R8A774C0)
compatible = "renesas,r8a774c0"
- R-Car M1A (R8A77781)
compatible = "renesas,r8a7778"
diff --git a/Documentation/devicetree/bindings/cpufreq/arm_big_little_dt.txt b/Documentation/devicetree/bindings/cpufreq/arm_big_little_dt.txt
deleted file mode 100644
index 2aa06ac0fac5..000000000000
--- a/Documentation/devicetree/bindings/cpufreq/arm_big_little_dt.txt
+++ /dev/null
@@ -1,65 +0,0 @@
-Generic ARM big LITTLE cpufreq driver's DT glue
------------------------------------------------
-
-This is DT specific glue layer for generic cpufreq driver for big LITTLE
-systems.
-
-Both required and optional properties listed below must be defined
-under node /cpus/cpu@x. Where x is the first cpu inside a cluster.
-
-FIXME: Cpus should boot in the order specified in DT and all cpus for a cluster
-must be present contiguously. Generic DT driver will check only node 'x' for
-cpu:x.
-
-Required properties:
-- operating-points: Refer to Documentation/devicetree/bindings/opp/opp.txt
- for details
-
-Optional properties:
-- clock-latency: Specify the possible maximum transition latency for clock,
- in unit of nanoseconds.
-
-Examples:
-
-cpus {
- #address-cells = <1>;
- #size-cells = <0>;
-
- cpu@0 {
- compatible = "arm,cortex-a15";
- reg = <0>;
- next-level-cache = <&L2>;
- operating-points = <
- /* kHz uV */
- 792000 1100000
- 396000 950000
- 198000 850000
- >;
- clock-latency = <61036>; /* two CLK32 periods */
- };
-
- cpu@1 {
- compatible = "arm,cortex-a15";
- reg = <1>;
- next-level-cache = <&L2>;
- };
-
- cpu@100 {
- compatible = "arm,cortex-a7";
- reg = <100>;
- next-level-cache = <&L2>;
- operating-points = <
- /* kHz uV */
- 792000 950000
- 396000 750000
- 198000 450000
- >;
- clock-latency = <61036>; /* two CLK32 periods */
- };
-
- cpu@101 {
- compatible = "arm,cortex-a7";
- reg = <101>;
- next-level-cache = <&L2>;
- };
-};
diff --git a/Documentation/devicetree/bindings/display/panel/innolux,tv123wam.txt b/Documentation/devicetree/bindings/display/panel/innolux,p120zdg-bf1.txt
index a9b35265fa13..513f03466aba 100644
--- a/Documentation/devicetree/bindings/display/panel/innolux,tv123wam.txt
+++ b/Documentation/devicetree/bindings/display/panel/innolux,p120zdg-bf1.txt
@@ -1,20 +1,22 @@
-Innolux TV123WAM 12.3 inch eDP 2K display panel
+Innolux P120ZDG-BF1 12.02 inch eDP 2K display panel
This binding is compatible with the simple-panel binding, which is specified
in simple-panel.txt in this directory.
Required properties:
-- compatible: should be "innolux,tv123wam"
+- compatible: should be "innolux,p120zdg-bf1"
- power-supply: regulator to provide the supply voltage
Optional properties:
- enable-gpios: GPIO pin to enable or disable the panel
- backlight: phandle of the backlight device attached to the panel
+- no-hpd: If HPD isn't hooked up; add this property.
Example:
panel_edp: panel-edp {
- compatible = "innolux,tv123wam";
+ compatible = "innolux,p120zdg-bf1";
enable-gpios = <&msmgpio 31 GPIO_ACTIVE_LOW>;
power-supply = <&pm8916_l2>;
backlight = <&backlight>;
+ no-hpd;
};
diff --git a/Documentation/devicetree/bindings/display/panel/simple-panel.txt b/Documentation/devicetree/bindings/display/panel/simple-panel.txt
index 45a457ad38f0..b2b872c710f2 100644
--- a/Documentation/devicetree/bindings/display/panel/simple-panel.txt
+++ b/Documentation/devicetree/bindings/display/panel/simple-panel.txt
@@ -11,6 +11,9 @@ Optional properties:
- ddc-i2c-bus: phandle of an I2C controller used for DDC EDID probing
- enable-gpios: GPIO pin to enable or disable the panel
- backlight: phandle of the backlight device attached to the panel
+- no-hpd: This panel is supposed to communicate that it's ready via HPD
+ (hot plug detect) signal, but the signal isn't hooked up so we should
+ hardcode the max delay from the panel spec when powering up the panel.
Example:
diff --git a/Documentation/devicetree/bindings/i2c/i2c-imx-lpi2c.txt b/Documentation/devicetree/bindings/i2c/i2c-imx-lpi2c.txt
index 091c8dfd3229..b245363d6d60 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-imx-lpi2c.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-imx-lpi2c.txt
@@ -3,6 +3,7 @@
Required properties:
- compatible :
- "fsl,imx7ulp-lpi2c" for LPI2C compatible with the one integrated on i.MX7ULP soc
+ - "fsl,imx8qxp-lpi2c" for LPI2C compatible with the one integrated on i.MX8QXP soc
- reg : address and length of the lpi2c master registers
- interrupts : lpi2c interrupt
- clocks : lpi2c clock specifier
diff --git a/Documentation/devicetree/bindings/i2c/i2c-omap.txt b/Documentation/devicetree/bindings/i2c/i2c-omap.txt
index 7e49839d4124..4b90ba9f31b7 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-omap.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-omap.txt
@@ -1,8 +1,12 @@
I2C for OMAP platforms
Required properties :
-- compatible : Must be "ti,omap2420-i2c", "ti,omap2430-i2c", "ti,omap3-i2c"
- or "ti,omap4-i2c"
+- compatible : Must be
+ "ti,omap2420-i2c" for OMAP2420 SoCs
+ "ti,omap2430-i2c" for OMAP2430 SoCs
+ "ti,omap3-i2c" for OMAP3 SoCs
+ "ti,omap4-i2c" for OMAP4+ SoCs
+ "ti,am654-i2c", "ti,omap4-i2c" for AM654 SoCs
- ti,hwmods : Must be "i2c<n>", n being the instance number (1-based)
- #address-cells = <1>;
- #size-cells = <0>;
diff --git a/Documentation/devicetree/bindings/net/can/holt_hi311x.txt b/Documentation/devicetree/bindings/net/can/holt_hi311x.txt
index 903a78da65be..3a9926f99937 100644
--- a/Documentation/devicetree/bindings/net/can/holt_hi311x.txt
+++ b/Documentation/devicetree/bindings/net/can/holt_hi311x.txt
@@ -17,7 +17,7 @@ Example:
reg = <1>;
clocks = <&clk32m>;
interrupt-parent = <&gpio4>;
- interrupts = <13 IRQ_TYPE_EDGE_RISING>;
+ interrupts = <13 IRQ_TYPE_LEVEL_HIGH>;
vdd-supply = <&reg5v0>;
xceiver-supply = <&reg5v0>;
};
diff --git a/Documentation/devicetree/bindings/net/can/rcar_can.txt b/Documentation/devicetree/bindings/net/can/rcar_can.txt
index cc4372842bf3..9936b9ee67c3 100644
--- a/Documentation/devicetree/bindings/net/can/rcar_can.txt
+++ b/Documentation/devicetree/bindings/net/can/rcar_can.txt
@@ -5,6 +5,7 @@ Required properties:
- compatible: "renesas,can-r8a7743" if CAN controller is a part of R8A7743 SoC.
"renesas,can-r8a7744" if CAN controller is a part of R8A7744 SoC.
"renesas,can-r8a7745" if CAN controller is a part of R8A7745 SoC.
+ "renesas,can-r8a774a1" if CAN controller is a part of R8A774A1 SoC.
"renesas,can-r8a7778" if CAN controller is a part of R8A7778 SoC.
"renesas,can-r8a7779" if CAN controller is a part of R8A7779 SoC.
"renesas,can-r8a7790" if CAN controller is a part of R8A7790 SoC.
@@ -14,26 +15,32 @@ Required properties:
"renesas,can-r8a7794" if CAN controller is a part of R8A7794 SoC.
"renesas,can-r8a7795" if CAN controller is a part of R8A7795 SoC.
"renesas,can-r8a7796" if CAN controller is a part of R8A7796 SoC.
+ "renesas,can-r8a77965" if CAN controller is a part of R8A77965 SoC.
"renesas,rcar-gen1-can" for a generic R-Car Gen1 compatible device.
"renesas,rcar-gen2-can" for a generic R-Car Gen2 or RZ/G1
compatible device.
- "renesas,rcar-gen3-can" for a generic R-Car Gen3 compatible device.
+ "renesas,rcar-gen3-can" for a generic R-Car Gen3 or RZ/G2
+ compatible device.
When compatible with the generic version, nodes must list the
SoC-specific version corresponding to the platform first
followed by the generic version.
- reg: physical base address and size of the R-Car CAN register map.
- interrupts: interrupt specifier for the sole interrupt.
-- clocks: phandles and clock specifiers for 3 CAN clock inputs.
-- clock-names: 3 clock input name strings: "clkp1", "clkp2", "can_clk".
+- clocks: phandles and clock specifiers for 2 CAN clock inputs for RZ/G2
+ devices.
+ phandles and clock specifiers for 3 CAN clock inputs for every other
+ SoC.
+- clock-names: 2 clock input name strings for RZ/G2: "clkp1", "can_clk".
+ 3 clock input name strings for every other SoC: "clkp1", "clkp2",
+ "can_clk".
- pinctrl-0: pin control group to be used for this controller.
- pinctrl-names: must be "default".
-Required properties for "renesas,can-r8a7795" and "renesas,can-r8a7796"
-compatible:
-In R8A7795 and R8A7796 SoCs, "clkp2" can be CANFD clock. This is a div6 clock
-and can be used by both CAN and CAN FD controller at the same time. It needs to
-be scaled to maximum frequency if any of these controllers use it. This is done
+Required properties for R8A7795, R8A7796 and R8A77965:
+For the denoted SoCs, "clkp2" can be CANFD clock. This is a div6 clock and can
+be used by both CAN and CAN FD controller at the same time. It needs to be
+scaled to maximum frequency if any of these controllers use it. This is done
using the below properties:
- assigned-clocks: phandle of clkp2(CANFD) clock.
@@ -42,8 +49,9 @@ using the below properties:
Optional properties:
- renesas,can-clock-select: R-Car CAN Clock Source Select. Valid values are:
<0x0> (default) : Peripheral clock (clkp1)
- <0x1> : Peripheral clock (clkp2)
- <0x3> : Externally input clock
+ <0x1> : Peripheral clock (clkp2) (not supported by
+ RZ/G2 devices)
+ <0x3> : External input clock
Example
-------
diff --git a/Documentation/devicetree/bindings/net/dsa/dsa.txt b/Documentation/devicetree/bindings/net/dsa/dsa.txt
index 3ceeb8de1196..35694c0c376b 100644
--- a/Documentation/devicetree/bindings/net/dsa/dsa.txt
+++ b/Documentation/devicetree/bindings/net/dsa/dsa.txt
@@ -7,7 +7,7 @@ limitations.
Current Binding
---------------
-Switches are true Linux devices and can be probes by any means. Once
+Switches are true Linux devices and can be probed by any means. Once
probed, they register to the DSA framework, passing a node
pointer. This node is expected to fulfil the following binding, and
may contain additional properties as required by the device it is
diff --git a/Documentation/devicetree/bindings/pwm/pwm-tiecap.txt b/Documentation/devicetree/bindings/pwm/pwm-tiecap.txt
index 06a363d9ccef..b9a1d7402128 100644
--- a/Documentation/devicetree/bindings/pwm/pwm-tiecap.txt
+++ b/Documentation/devicetree/bindings/pwm/pwm-tiecap.txt
@@ -7,6 +7,7 @@ Required properties:
for da850 - compatible = "ti,da850-ecap", "ti,am3352-ecap", "ti,am33xx-ecap";
for dra746 - compatible = "ti,dra746-ecap", "ti,am3352-ecap";
for 66ak2g - compatible = "ti,k2g-ecap", "ti,am3352-ecap";
+ for am654 - compatible = "ti,am654-ecap", "ti,am3352-ecap";
- #pwm-cells: should be 3. See pwm.txt in this directory for a description of
the cells format. The PWM channel index ranges from 0 to 4. The only third
cell flag supported by this binding is PWM_POLARITY_INVERTED.
diff --git a/Documentation/devicetree/bindings/pwm/renesas,pwm-rcar.txt b/Documentation/devicetree/bindings/pwm/renesas,pwm-rcar.txt
index e1ef6afbe3a7..7f31fe7e2093 100644
--- a/Documentation/devicetree/bindings/pwm/renesas,pwm-rcar.txt
+++ b/Documentation/devicetree/bindings/pwm/renesas,pwm-rcar.txt
@@ -3,7 +3,9 @@
Required Properties:
- compatible: should be "renesas,pwm-rcar" and one of the following.
- "renesas,pwm-r8a7743": for RZ/G1M
+ - "renesas,pwm-r8a7744": for RZ/G1N
- "renesas,pwm-r8a7745": for RZ/G1E
+ - "renesas,pwm-r8a774a1": for RZ/G2M
- "renesas,pwm-r8a7778": for R-Car M1A
- "renesas,pwm-r8a7779": for R-Car H1
- "renesas,pwm-r8a7790": for R-Car H2
@@ -12,6 +14,8 @@ Required Properties:
- "renesas,pwm-r8a7795": for R-Car H3
- "renesas,pwm-r8a7796": for R-Car M3-W
- "renesas,pwm-r8a77965": for R-Car M3-N
+ - "renesas,pwm-r8a77970": for R-Car V3M
+ - "renesas,pwm-r8a77980": for R-Car V3H
- "renesas,pwm-r8a77990": for R-Car E3
- "renesas,pwm-r8a77995": for R-Car D3
- reg: base address and length of the registers block for the PWM.
diff --git a/Documentation/devicetree/bindings/pwm/renesas,tpu-pwm.txt b/Documentation/devicetree/bindings/pwm/renesas,tpu-pwm.txt
index d53a16715da6..848a92b53d81 100644
--- a/Documentation/devicetree/bindings/pwm/renesas,tpu-pwm.txt
+++ b/Documentation/devicetree/bindings/pwm/renesas,tpu-pwm.txt
@@ -2,13 +2,19 @@
Required Properties:
- - compatible: should be one of the following.
+ - compatible: must contain one or more of the following:
- "renesas,tpu-r8a73a4": for R8A73A4 (R-Mobile APE6) compatible PWM controller.
- "renesas,tpu-r8a7740": for R8A7740 (R-Mobile A1) compatible PWM controller.
- "renesas,tpu-r8a7743": for R8A7743 (RZ/G1M) compatible PWM controller.
+ - "renesas,tpu-r8a7744": for R8A7744 (RZ/G1N) compatible PWM controller.
- "renesas,tpu-r8a7745": for R8A7745 (RZ/G1E) compatible PWM controller.
- "renesas,tpu-r8a7790": for R8A7790 (R-Car H2) compatible PWM controller.
- - "renesas,tpu": for generic R-Car and RZ/G1 TPU PWM controller.
+ - "renesas,tpu-r8a77970": for R8A77970 (R-Car V3M) compatible PWM
+ controller.
+ - "renesas,tpu-r8a77980": for R8A77980 (R-Car V3H) compatible PWM
+ controller.
+ - "renesas,tpu": for the generic TPU PWM controller; this is a fallback for
+ the entries listed above.
- reg: Base address and length of each memory resource used by the PWM
controller hardware module.
diff --git a/Documentation/devicetree/bindings/timer/csky,gx6605s-timer.txt b/Documentation/devicetree/bindings/timer/csky,gx6605s-timer.txt
new file mode 100644
index 000000000000..6b04344f4bea
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/csky,gx6605s-timer.txt
@@ -0,0 +1,42 @@
+=================
+gx6605s SOC Timer
+=================
+
+The timer is used in gx6605s soc as system timer and the driver
+contain clk event and clk source.
+
+==============================
+timer node bindings definition
+==============================
+
+ Description: Describes gx6605s SOC timer
+
+ PROPERTIES
+
+ - compatible
+ Usage: required
+ Value type: <string>
+ Definition: must be "csky,gx6605s-timer"
+ - reg
+ Usage: required
+ Value type: <u32 u32>
+ Definition: <phyaddr size> in soc from cpu view
+ - clocks
+ Usage: required
+ Value type: phandle + clock specifier cells
+ Definition: must be input clk node
+ - interrupt
+ Usage: required
+ Value type: <u32>
+ Definition: must be timer irq num defined by soc
+
+Examples:
+---------
+
+ timer0: timer@20a000 {
+ compatible = "csky,gx6605s-timer";
+ reg = <0x0020a000 0x400>;
+ clocks = <&dummy_apb_clk>;
+ interrupts = <10>;
+ interrupt-parent = <&intc>;
+ };
diff --git a/Documentation/devicetree/bindings/timer/csky,mptimer.txt b/Documentation/devicetree/bindings/timer/csky,mptimer.txt
new file mode 100644
index 000000000000..15cfec08fbb8
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/csky,mptimer.txt
@@ -0,0 +1,42 @@
+============================
+C-SKY Multi-processors Timer
+============================
+
+C-SKY multi-processors timer is designed for C-SKY SMP system and the
+regs is accessed by cpu co-processor 4 registers with mtcr/mfcr.
+
+ - PTIM_CTLR "cr<0, 14>" Control reg to start reset timer.
+ - PTIM_TSR "cr<1, 14>" Interrupt cleanup status reg.
+ - PTIM_CCVR "cr<3, 14>" Current counter value reg.
+ - PTIM_LVR "cr<6, 14>" Window value reg to triger next event.
+
+==============================
+timer node bindings definition
+==============================
+
+ Description: Describes SMP timer
+
+ PROPERTIES
+
+ - compatible
+ Usage: required
+ Value type: <string>
+ Definition: must be "csky,mptimer"
+ - clocks
+ Usage: required
+ Value type: <node>
+ Definition: must be input clk node
+ - interrupts
+ Usage: required
+ Value type: <u32>
+ Definition: must be timer irq num defined by soc
+
+Examples:
+---------
+
+ timer: timer {
+ compatible = "csky,mptimer";
+ clocks = <&dummy_apb_clk>;
+ interrupts = <16>;
+ interrupt-parent = <&intc>;
+ };
diff --git a/Documentation/filesystems/overlayfs.txt b/Documentation/filesystems/overlayfs.txt
index 51c136c821bf..eef7d9d259e8 100644
--- a/Documentation/filesystems/overlayfs.txt
+++ b/Documentation/filesystems/overlayfs.txt
@@ -286,6 +286,12 @@ pointed by REDIRECT. This should not be possible on local system as setting
"trusted." xattrs will require CAP_SYS_ADMIN. But it should be possible
for untrusted layers like from a pen drive.
+Note: redirect_dir={off|nofollow|follow(*)} conflicts with metacopy=on, and
+results in an error.
+
+(*) redirect_dir=follow only conflicts with metacopy=on if upperdir=... is
+given.
+
Sharing and copying layers
--------------------------
diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting
index 321d74b73937..cf43bc4dbf31 100644
--- a/Documentation/filesystems/porting
+++ b/Documentation/filesystems/porting
@@ -623,6 +623,11 @@ in your dentry operations instead.
On success you get a new struct file sharing the mount/dentry with the
original, on failure - ERR_PTR().
--
+[mandatory]
+ ->clone_file_range() and ->dedupe_file_range have been replaced with
+ ->remap_file_range(). See Documentation/filesystems/vfs.txt for more
+ information.
+--
[recommended]
->lookup() instances doing an equivalent of
if (IS_ERR(inode))
diff --git a/Documentation/filesystems/ubifs-authentication.md b/Documentation/filesystems/ubifs-authentication.md
new file mode 100644
index 000000000000..028b3e2e25f9
--- /dev/null
+++ b/Documentation/filesystems/ubifs-authentication.md
@@ -0,0 +1,426 @@
+% UBIFS Authentication
+% sigma star gmbh
+% 2018
+
+# Introduction
+
+UBIFS utilizes the fscrypt framework to provide confidentiality for file
+contents and file names. This prevents attacks where an attacker is able to
+read contents of the filesystem on a single point in time. A classic example
+is a lost smartphone where the attacker is unable to read personal data stored
+on the device without the filesystem decryption key.
+
+At the current state, UBIFS encryption however does not prevent attacks where
+the attacker is able to modify the filesystem contents and the user uses the
+device afterwards. In such a scenario an attacker can modify filesystem
+contents arbitrarily without the user noticing. One example is to modify a
+binary to perform a malicious action when executed [DMC-CBC-ATTACK]. Since
+most of the filesystem metadata of UBIFS is stored in plain, this makes it
+fairly easy to swap files and replace their contents.
+
+Other full disk encryption systems like dm-crypt cover all filesystem metadata,
+which makes such kinds of attacks more complicated, but not impossible.
+Especially, if the attacker is given access to the device multiple points in
+time. For dm-crypt and other filesystems that build upon the Linux block IO
+layer, the dm-integrity or dm-verity subsystems [DM-INTEGRITY, DM-VERITY]
+can be used to get full data authentication at the block layer.
+These can also be combined with dm-crypt [CRYPTSETUP2].
+
+This document describes an approach to get file contents _and_ full metadata
+authentication for UBIFS. Since UBIFS uses fscrypt for file contents and file
+name encryption, the authentication system could be tied into fscrypt such that
+existing features like key derivation can be utilized. It should however also
+be possible to use UBIFS authentication without using encryption.
+
+
+## MTD, UBI & UBIFS
+
+On Linux, the MTD (Memory Technology Devices) subsystem provides a uniform
+interface to access raw flash devices. One of the more prominent subsystems that
+work on top of MTD is UBI (Unsorted Block Images). It provides volume management
+for flash devices and is thus somewhat similar to LVM for block devices. In
+addition, it deals with flash-specific wear-leveling and transparent I/O error
+handling. UBI offers logical erase blocks (LEBs) to the layers on top of it
+and maps them transparently to physical erase blocks (PEBs) on the flash.
+
+UBIFS is a filesystem for raw flash which operates on top of UBI. Thus, wear
+leveling and some flash specifics are left to UBI, while UBIFS focuses on
+scalability, performance and recoverability.
+
+
+
+ +------------+ +*******+ +-----------+ +-----+
+ | | * UBIFS * | UBI-BLOCK | | ... |
+ | JFFS/JFFS2 | +*******+ +-----------+ +-----+
+ | | +-----------------------------+ +-----------+ +-----+
+ | | | UBI | | MTD-BLOCK | | ... |
+ +------------+ +-----------------------------+ +-----------+ +-----+
+ +------------------------------------------------------------------+
+ | MEMORY TECHNOLOGY DEVICES (MTD) |
+ +------------------------------------------------------------------+
+ +-----------------------------+ +--------------------------+ +-----+
+ | NAND DRIVERS | | NOR DRIVERS | | ... |
+ +-----------------------------+ +--------------------------+ +-----+
+
+ Figure 1: Linux kernel subsystems for dealing with raw flash
+
+
+
+Internally, UBIFS maintains multiple data structures which are persisted on
+the flash:
+
+- *Index*: an on-flash B+ tree where the leaf nodes contain filesystem data
+- *Journal*: an additional data structure to collect FS changes before updating
+ the on-flash index and reduce flash wear.
+- *Tree Node Cache (TNC)*: an in-memory B+ tree that reflects the current FS
+ state to avoid frequent flash reads. It is basically the in-memory
+ representation of the index, but contains additional attributes.
+- *LEB property tree (LPT)*: an on-flash B+ tree for free space accounting per
+ UBI LEB.
+
+In the remainder of this section we will cover the on-flash UBIFS data
+structures in more detail. The TNC is of less importance here since it is never
+persisted onto the flash directly. More details on UBIFS can also be found in
+[UBIFS-WP].
+
+
+### UBIFS Index & Tree Node Cache
+
+Basic on-flash UBIFS entities are called *nodes*. UBIFS knows different types
+of nodes. Eg. data nodes (`struct ubifs_data_node`) which store chunks of file
+contents or inode nodes (`struct ubifs_ino_node`) which represent VFS inodes.
+Almost all types of nodes share a common header (`ubifs_ch`) containing basic
+information like node type, node length, a sequence number, etc. (see
+`fs/ubifs/ubifs-media.h`in kernel source). Exceptions are entries of the LPT
+and some less important node types like padding nodes which are used to pad
+unusable content at the end of LEBs.
+
+To avoid re-writing the whole B+ tree on every single change, it is implemented
+as *wandering tree*, where only the changed nodes are re-written and previous
+versions of them are obsoleted without erasing them right away. As a result,
+the index is not stored in a single place on the flash, but *wanders* around
+and there are obsolete parts on the flash as long as the LEB containing them is
+not reused by UBIFS. To find the most recent version of the index, UBIFS stores
+a special node called *master node* into UBI LEB 1 which always points to the
+most recent root node of the UBIFS index. For recoverability, the master node
+is additionally duplicated to LEB 2. Mounting UBIFS is thus a simple read of
+LEB 1 and 2 to get the current master node and from there get the location of
+the most recent on-flash index.
+
+The TNC is the in-memory representation of the on-flash index. It contains some
+additional runtime attributes per node which are not persisted. One of these is
+a dirty-flag which marks nodes that have to be persisted the next time the
+index is written onto the flash. The TNC acts as a write-back cache and all
+modifications of the on-flash index are done through the TNC. Like other caches,
+the TNC does not have to mirror the full index into memory, but reads parts of
+it from flash whenever needed. A *commit* is the UBIFS operation of updating the
+on-flash filesystem structures like the index. On every commit, the TNC nodes
+marked as dirty are written to the flash to update the persisted index.
+
+
+### Journal
+
+To avoid wearing out the flash, the index is only persisted (*commited*) when
+certain conditions are met (eg. `fsync(2)`). The journal is used to record
+any changes (in form of inode nodes, data nodes etc.) between commits
+of the index. During mount, the journal is read from the flash and replayed
+onto the TNC (which will be created on-demand from the on-flash index).
+
+UBIFS reserves a bunch of LEBs just for the journal called *log area*. The
+amount of log area LEBs is configured on filesystem creation (using
+`mkfs.ubifs`) and stored in the superblock node. The log area contains only
+two types of nodes: *reference nodes* and *commit start nodes*. A commit start
+node is written whenever an index commit is performed. Reference nodes are
+written on every journal update. Each reference node points to the position of
+other nodes (inode nodes, data nodes etc.) on the flash that are part of this
+journal entry. These nodes are called *buds* and describe the actual filesystem
+changes including their data.
+
+The log area is maintained as a ring. Whenever the journal is almost full,
+a commit is initiated. This also writes a commit start node so that during
+mount, UBIFS will seek for the most recent commit start node and just replay
+every reference node after that. Every reference node before the commit start
+node will be ignored as they are already part of the on-flash index.
+
+When writing a journal entry, UBIFS first ensures that enough space is
+available to write the reference node and buds part of this entry. Then, the
+reference node is written and afterwards the buds describing the file changes.
+On replay, UBIFS will record every reference node and inspect the location of
+the referenced LEBs to discover the buds. If these are corrupt or missing,
+UBIFS will attempt to recover them by re-reading the LEB. This is however only
+done for the last referenced LEB of the journal. Only this can become corrupt
+because of a power cut. If the recovery fails, UBIFS will not mount. An error
+for every other LEB will directly cause UBIFS to fail the mount operation.
+
+
+ | ---- LOG AREA ---- | ---------- MAIN AREA ------------ |
+
+ -----+------+-----+--------+---- ------+-----+-----+---------------
+ \ | | | | / / | | | \
+ / CS | REF | REF | | \ \ DENT | INO | INO | /
+ \ | | | | / / | | | \
+ ----+------+-----+--------+--- -------+-----+-----+----------------
+ | | ^ ^
+ | | | |
+ +------------------------+ |
+ | |
+ +-------------------------------+
+
+
+ Figure 2: UBIFS flash layout of log area with commit start nodes
+ (CS) and reference nodes (REF) pointing to main area
+ containing their buds
+
+
+### LEB Property Tree/Table
+
+The LEB property tree is used to store per-LEB information. This includes the
+LEB type and amount of free and *dirty* (old, obsolete content) space [1] on
+the LEB. The type is important, because UBIFS never mixes index nodes with data
+nodes on a single LEB and thus each LEB has a specific purpose. This again is
+useful for free space calculations. See [UBIFS-WP] for more details.
+
+The LEB property tree again is a B+ tree, but it is much smaller than the
+index. Due to its smaller size it is always written as one chunk on every
+commit. Thus, saving the LPT is an atomic operation.
+
+
+[1] Since LEBs can only be appended and never overwritten, there is a
+difference between free space ie. the remaining space left on the LEB to be
+written to without erasing it and previously written content that is obsolete
+but can't be overwritten without erasing the full LEB.
+
+
+# UBIFS Authentication
+
+This chapter introduces UBIFS authentication which enables UBIFS to verify
+the authenticity and integrity of metadata and file contents stored on flash.
+
+
+## Threat Model
+
+UBIFS authentication enables detection of offline data modification. While it
+does not prevent it, it enables (trusted) code to check the integrity and
+authenticity of on-flash file contents and filesystem metadata. This covers
+attacks where file contents are swapped.
+
+UBIFS authentication will not protect against rollback of full flash contents.
+Ie. an attacker can still dump the flash and restore it at a later time without
+detection. It will also not protect against partial rollback of individual
+index commits. That means that an attacker is able to partially undo changes.
+This is possible because UBIFS does not immediately overwrites obsolete
+versions of the index tree or the journal, but instead marks them as obsolete
+and garbage collection erases them at a later time. An attacker can use this by
+erasing parts of the current tree and restoring old versions that are still on
+the flash and have not yet been erased. This is possible, because every commit
+will always write a new version of the index root node and the master node
+without overwriting the previous version. This is further helped by the
+wear-leveling operations of UBI which copies contents from one physical
+eraseblock to another and does not atomically erase the first eraseblock.
+
+UBIFS authentication does not cover attacks where an attacker is able to
+execute code on the device after the authentication key was provided.
+Additional measures like secure boot and trusted boot have to be taken to
+ensure that only trusted code is executed on a device.
+
+
+## Authentication
+
+To be able to fully trust data read from flash, all UBIFS data structures
+stored on flash are authenticated. That is:
+
+- The index which includes file contents, file metadata like extended
+ attributes, file length etc.
+- The journal which also contains file contents and metadata by recording changes
+ to the filesystem
+- The LPT which stores UBI LEB metadata which UBIFS uses for free space accounting
+
+
+### Index Authentication
+
+Through UBIFS' concept of a wandering tree, it already takes care of only
+updating and persisting changed parts from leaf node up to the root node
+of the full B+ tree. This enables us to augment the index nodes of the tree
+with a hash over each node's child nodes. As a result, the index basically also
+a Merkle tree. Since the leaf nodes of the index contain the actual filesystem
+data, the hashes of their parent index nodes thus cover all the file contents
+and file metadata. When a file changes, the UBIFS index is updated accordingly
+from the leaf nodes up to the root node including the master node. This process
+can be hooked to recompute the hash only for each changed node at the same time.
+Whenever a file is read, UBIFS can verify the hashes from each leaf node up to
+the root node to ensure the node's integrity.
+
+To ensure the authenticity of the whole index, the UBIFS master node stores a
+keyed hash (HMAC) over its own contents and a hash of the root node of the index
+tree. As mentioned above, the master node is always written to the flash whenever
+the index is persisted (ie. on index commit).
+
+Using this approach only UBIFS index nodes and the master node are changed to
+include a hash. All other types of nodes will remain unchanged. This reduces
+the storage overhead which is precious for users of UBIFS (ie. embedded
+devices).
+
+
+ +---------------+
+ | Master Node |
+ | (hash) |
+ +---------------+
+ |
+ v
+ +-------------------+
+ | Index Node #1 |
+ | |
+ | branch0 branchn |
+ | (hash) (hash) |
+ +-------------------+
+ | ... | (fanout: 8)
+ | |
+ +-------+ +------+
+ | |
+ v v
+ +-------------------+ +-------------------+
+ | Index Node #2 | | Index Node #3 |
+ | | | |
+ | branch0 branchn | | branch0 branchn |
+ | (hash) (hash) | | (hash) (hash) |
+ +-------------------+ +-------------------+
+ | ... | ... |
+ v v v
+ +-----------+ +----------+ +-----------+
+ | Data Node | | INO Node | | DENT Node |
+ +-----------+ +----------+ +-----------+
+
+
+ Figure 3: Coverage areas of index node hash and master node HMAC
+
+
+
+The most important part for robustness and power-cut safety is to atomically
+persist the hash and file contents. Here the existing UBIFS logic for how
+changed nodes are persisted is already designed for this purpose such that
+UBIFS can safely recover if a power-cut occurs while persisting. Adding
+hashes to index nodes does not change this since each hash will be persisted
+atomically together with its respective node.
+
+
+### Journal Authentication
+
+The journal is authenticated too. Since the journal is continuously written
+it is necessary to also add authentication information frequently to the
+journal so that in case of a powercut not too much data can't be authenticated.
+This is done by creating a continuous hash beginning from the commit start node
+over the previous reference nodes, the current reference node, and the bud
+nodes. From time to time whenever it is suitable authentication nodes are added
+between the bud nodes. This new node type contains a HMAC over the current state
+of the hash chain. That way a journal can be authenticated up to the last
+authentication node. The tail of the journal which may not have a authentication
+node cannot be authenticated and is skipped during journal replay.
+
+We get this picture for journal authentication:
+
+ ,,,,,,,,
+ ,......,...........................................
+ ,. CS , hash1.----. hash2.----.
+ ,. | , . |hmac . |hmac
+ ,. v , . v . v
+ ,.REF#0,-> bud -> bud -> bud.-> auth -> bud -> bud.-> auth ...
+ ,..|...,...........................................
+ , | ,
+ , | ,,,,,,,,,,,,,,,
+ . | hash3,----.
+ , | , |hmac
+ , v , v
+ , REF#1 -> bud -> bud,-> auth ...
+ ,,,|,,,,,,,,,,,,,,,,,,
+ v
+ REF#2 -> ...
+ |
+ V
+ ...
+
+Since the hash also includes the reference nodes an attacker cannot reorder or
+skip any journal heads for replay. An attacker can only remove bud nodes or
+reference nodes from the end of the journal, effectively rewinding the
+filesystem at maximum back to the last commit.
+
+The location of the log area is stored in the master node. Since the master
+node is authenticated with a HMAC as described above, it is not possible to
+tamper with that without detection. The size of the log area is specified when
+the filesystem is created using `mkfs.ubifs` and stored in the superblock node.
+To avoid tampering with this and other values stored there, a HMAC is added to
+the superblock struct. The superblock node is stored in LEB 0 and is only
+modified on feature flag or similar changes, but never on file changes.
+
+
+### LPT Authentication
+
+The location of the LPT root node on the flash is stored in the UBIFS master
+node. Since the LPT is written and read atomically on every commit, there is
+no need to authenticate individual nodes of the tree. It suffices to
+protect the integrity of the full LPT by a simple hash stored in the master
+node. Since the master node itself is authenticated, the LPTs authenticity can
+be verified by verifying the authenticity of the master node and comparing the
+LTP hash stored there with the hash computed from the read on-flash LPT.
+
+
+## Key Management
+
+For simplicity, UBIFS authentication uses a single key to compute the HMACs
+of superblock, master, commit start and reference nodes. This key has to be
+available on creation of the filesystem (`mkfs.ubifs`) to authenticate the
+superblock node. Further, it has to be available on mount of the filesystem
+to verify authenticated nodes and generate new HMACs for changes.
+
+UBIFS authentication is intended to operate side-by-side with UBIFS encryption
+(fscrypt) to provide confidentiality and authenticity. Since UBIFS encryption
+has a different approach of encryption policies per directory, there can be
+multiple fscrypt master keys and there might be folders without encryption.
+UBIFS authentication on the other hand has an all-or-nothing approach in the
+sense that it either authenticates everything of the filesystem or nothing.
+Because of this and because UBIFS authentication should also be usable without
+encryption, it does not share the same master key with fscrypt, but manages
+a dedicated authentication key.
+
+The API for providing the authentication key has yet to be defined, but the
+key can eg. be provided by userspace through a keyring similar to the way it
+is currently done in fscrypt. It should however be noted that the current
+fscrypt approach has shown its flaws and the userspace API will eventually
+change [FSCRYPT-POLICY2].
+
+Nevertheless, it will be possible for a user to provide a single passphrase
+or key in userspace that covers UBIFS authentication and encryption. This can
+be solved by the corresponding userspace tools which derive a second key for
+authentication in addition to the derived fscrypt master key used for
+encryption.
+
+To be able to check if the proper key is available on mount, the UBIFS
+superblock node will additionally store a hash of the authentication key. This
+approach is similar to the approach proposed for fscrypt encryption policy v2
+[FSCRYPT-POLICY2].
+
+
+# Future Extensions
+
+In certain cases where a vendor wants to provide an authenticated filesystem
+image to customers, it should be possible to do so without sharing the secret
+UBIFS authentication key. Instead, in addition the each HMAC a digital
+signature could be stored where the vendor shares the public key alongside the
+filesystem image. In case this filesystem has to be modified afterwards,
+UBIFS can exchange all digital signatures with HMACs on first mount similar
+to the way the IMA/EVM subsystem deals with such situations. The HMAC key
+will then have to be provided beforehand in the normal way.
+
+
+# References
+
+[CRYPTSETUP2] http://www.saout.de/pipermail/dm-crypt/2017-November/005745.html
+
+[DMC-CBC-ATTACK] http://www.jakoblell.com/blog/2013/12/22/practical-malleability-attack-against-cbc-encrypted-luks-partitions/
+
+[DM-INTEGRITY] https://www.kernel.org/doc/Documentation/device-mapper/dm-integrity.txt
+
+[DM-VERITY] https://www.kernel.org/doc/Documentation/device-mapper/verity.txt
+
+[FSCRYPT-POLICY2] https://www.spinics.net/lists/linux-ext4/msg58710.html
+
+[UBIFS-WP] http://www.linux-mtd.infradead.org/doc/ubifs_whitepaper.pdf
diff --git a/Documentation/filesystems/ubifs.txt b/Documentation/filesystems/ubifs.txt
index a0a61d2f389f..acc80442a3bb 100644
--- a/Documentation/filesystems/ubifs.txt
+++ b/Documentation/filesystems/ubifs.txt
@@ -91,6 +91,13 @@ chk_data_crc do not skip checking CRCs on data nodes
compr=none override default compressor and set it to "none"
compr=lzo override default compressor and set it to "lzo"
compr=zlib override default compressor and set it to "zlib"
+auth_key= specify the key used for authenticating the filesystem.
+ Passing this option makes authentication mandatory.
+ The passed key must be present in the kernel keyring
+ and must be of type 'logon'
+auth_hash_name= The hash algorithm used for authentication. Used for
+ both hashing and for creating HMACs. Typical values
+ include "sha256" or "sha512"
Quick usage instructions
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index a6c6a8af48a2..5f71a252e2e0 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -883,8 +883,9 @@ struct file_operations {
unsigned (*mmap_capabilities)(struct file *);
#endif
ssize_t (*copy_file_range)(struct file *, loff_t, struct file *, loff_t, size_t, unsigned int);
- int (*clone_file_range)(struct file *, loff_t, struct file *, loff_t, u64);
- int (*dedupe_file_range)(struct file *, loff_t, struct file *, loff_t, u64);
+ loff_t (*remap_file_range)(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out,
+ loff_t len, unsigned int remap_flags);
int (*fadvise)(struct file *, loff_t, loff_t, int);
};
@@ -960,11 +961,18 @@ otherwise noted.
copy_file_range: called by the copy_file_range(2) system call.
- clone_file_range: called by the ioctl(2) system call for FICLONERANGE and
- FICLONE commands.
-
- dedupe_file_range: called by the ioctl(2) system call for FIDEDUPERANGE
- command.
+ remap_file_range: called by the ioctl(2) system call for FICLONERANGE and
+ FICLONE and FIDEDUPERANGE commands to remap file ranges. An
+ implementation should remap len bytes at pos_in of the source file into
+ the dest file at pos_out. Implementations must handle callers passing
+ in len == 0; this means "remap to the end of the source file". The
+ return value should the number of bytes remapped, or the usual
+ negative error code if errors occurred before any bytes were remapped.
+ The remap_flags parameter accepts REMAP_FILE_* flags. If
+ REMAP_FILE_DEDUP is set then the implementation must only remap if the
+ requested file ranges have identical contents. If REMAP_CAN_SHORTEN is
+ set, the caller is ok with the implementation shortening the request
+ length to satisfy alignment or EOF requirements (or any other reason).
fadvise: possibly called by the fadvise64() system call.
diff --git a/Documentation/i2c/busses/i2c-nvidia-gpu b/Documentation/i2c/busses/i2c-nvidia-gpu
new file mode 100644
index 000000000000..31884d2b2eb5
--- /dev/null
+++ b/Documentation/i2c/busses/i2c-nvidia-gpu
@@ -0,0 +1,18 @@
+Kernel driver i2c-nvidia-gpu
+
+Datasheet: not publicly available.
+
+Authors:
+ Ajay Gupta <ajayg@nvidia.com>
+
+Description
+-----------
+
+i2c-nvidia-gpu is a driver for I2C controller included in NVIDIA Turing
+and later GPUs and it is used to communicate with Type-C controller on GPUs.
+
+If your 'lspci -v' listing shows something like the following,
+
+01:00.3 Serial bus controller [0c80]: NVIDIA Corporation Device 1ad9 (rev a1)
+
+then this driver should support the I2C controller of your GPU.
diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt
index 7b6a2b2bdc98..8da26c6dd886 100644
--- a/Documentation/kbuild/makefiles.txt
+++ b/Documentation/kbuild/makefiles.txt
@@ -537,21 +537,6 @@ more details, with real examples.
The third parameter may be a text as in this example, but it may also
be an expanded variable or a macro.
- cc-fullversion
- cc-fullversion is useful when the exact version of gcc is needed.
- One typical use-case is when a specific GCC version is broken.
- cc-fullversion points out a more specific version than cc-version does.
-
- Example:
- #arch/powerpc/Makefile
- $(Q)if test "$(cc-fullversion)" = "040200" ; then \
- echo -n '*** GCC-4.2.0 cannot compile the 64-bit powerpc ' ; \
- false ; \
- fi
-
- In this example for a specific GCC version the build will error out
- explaining to the user why it stops.
-
cc-cross-prefix
cc-cross-prefix is used to check if there exists a $(CC) in path with
one of the listed prefixes. The first prefix where there exist a
diff --git a/Documentation/media/uapi/v4l/dev-meta.rst b/Documentation/media/uapi/v4l/dev-meta.rst
index f7ac8d0d3af1..b65dc078abeb 100644
--- a/Documentation/media/uapi/v4l/dev-meta.rst
+++ b/Documentation/media/uapi/v4l/dev-meta.rst
@@ -40,7 +40,7 @@ To use the :ref:`format` ioctls applications set the ``type`` field of the
the desired operation. Both drivers and applications must set the remainder of
the :c:type:`v4l2_format` structure to 0.
-.. _v4l2-meta-format:
+.. c:type:: v4l2_meta_format
.. tabularcolumns:: |p{1.4cm}|p{2.2cm}|p{13.9cm}|
diff --git a/Documentation/media/uapi/v4l/vidioc-g-fmt.rst b/Documentation/media/uapi/v4l/vidioc-g-fmt.rst
index 3ead350e099f..9ea494a8faca 100644
--- a/Documentation/media/uapi/v4l/vidioc-g-fmt.rst
+++ b/Documentation/media/uapi/v4l/vidioc-g-fmt.rst
@@ -133,6 +133,11 @@ The format as returned by :ref:`VIDIOC_TRY_FMT <VIDIOC_G_FMT>` must be identical
- Definition of a data format, see :ref:`pixfmt`, used by SDR
capture and output devices.
* -
+ - struct :c:type:`v4l2_meta_format`
+ - ``meta``
+ - Definition of a metadata format, see :ref:`meta-formats`, used by
+ metadata capture devices.
+ * -
- __u8
- ``raw_data``\ [200]
- Place holder for future extensions.
diff --git a/Documentation/networking/ice.rst b/Documentation/networking/ice.rst
index 1e4948c9e989..4d118b827bbb 100644
--- a/Documentation/networking/ice.rst
+++ b/Documentation/networking/ice.rst
@@ -20,7 +20,7 @@ Enabling the driver
The driver is enabled via the standard kernel configuration system,
using the make command::
- make oldconfig/silentoldconfig/menuconfig/etc.
+ make oldconfig/menuconfig/etc.
The driver is located in the menu structure at:
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index 163b5ff1073c..32b21571adfe 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -316,6 +316,17 @@ tcp_frto - INTEGER
By default it's enabled with a non-zero value. 0 disables F-RTO.
+tcp_fwmark_accept - BOOLEAN
+ If set, incoming connections to listening sockets that do not have a
+ socket mark will set the mark of the accepting socket to the fwmark of
+ the incoming SYN packet. This will cause all packets on that connection
+ (starting from the first SYNACK) to be sent with that fwmark. The
+ listening socket's mark is unchanged. Listening sockets that already
+ have a fwmark set via setsockopt(SOL_SOCKET, SO_MARK, ...) are
+ unaffected.
+
+ Default: 0
+
tcp_invalid_ratelimit - INTEGER
Limit the maximal rate for sending duplicate acknowledgments
in response to incoming TCP packets that are for an existing
diff --git a/Documentation/networking/rxrpc.txt b/Documentation/networking/rxrpc.txt
index 605e00cdd6be..89f1302d593a 100644
--- a/Documentation/networking/rxrpc.txt
+++ b/Documentation/networking/rxrpc.txt
@@ -1056,18 +1056,23 @@ The kernel interface functions are as follows:
u32 rxrpc_kernel_check_life(struct socket *sock,
struct rxrpc_call *call);
+ void rxrpc_kernel_probe_life(struct socket *sock,
+ struct rxrpc_call *call);
- This returns a number that is updated when ACKs are received from the peer
- (notably including PING RESPONSE ACKs which we can elicit by sending PING
- ACKs to see if the call still exists on the server). The caller should
- compare the numbers of two calls to see if the call is still alive after
- waiting for a suitable interval.
+ The first function returns a number that is updated when ACKs are received
+ from the peer (notably including PING RESPONSE ACKs which we can elicit by
+ sending PING ACKs to see if the call still exists on the server). The
+ caller should compare the numbers of two calls to see if the call is still
+ alive after waiting for a suitable interval.
This allows the caller to work out if the server is still contactable and
if the call is still alive on the server whilst waiting for the server to
process a client operation.
- This function may transmit a PING ACK.
+ The second function causes a ping ACK to be transmitted to try to provoke
+ the peer into responding, which would then cause the value returned by the
+ first function to change. Note that this must be called in TASK_RUNNING
+ state.
(*) Get reply timestamp.
diff --git a/Documentation/process/index.rst b/Documentation/process/index.rst
index 757808526d9a..878ebfda7eef 100644
--- a/Documentation/process/index.rst
+++ b/Documentation/process/index.rst
@@ -25,6 +25,7 @@ Below are the essential guides that every developer should read.
code-of-conduct-interpretation
development-process
submitting-patches
+ programming-language
coding-style
maintainer-pgp-guide
email-clients
diff --git a/Documentation/process/programming-language.rst b/Documentation/process/programming-language.rst
new file mode 100644
index 000000000000..e5f5f065dc24
--- /dev/null
+++ b/Documentation/process/programming-language.rst
@@ -0,0 +1,45 @@
+.. _programming_language:
+
+Programming Language
+====================
+
+The kernel is written in the C programming language [c-language]_.
+More precisely, the kernel is typically compiled with ``gcc`` [gcc]_
+under ``-std=gnu89`` [gcc-c-dialect-options]_: the GNU dialect of ISO C90
+(including some C99 features).
+
+This dialect contains many extensions to the language [gnu-extensions]_,
+and many of them are used within the kernel as a matter of course.
+
+There is some support for compiling the kernel with ``clang`` [clang]_
+and ``icc`` [icc]_ for several of the architectures, although at the time
+of writing it is not completed, requiring third-party patches.
+
+Attributes
+----------
+
+One of the common extensions used throughout the kernel are attributes
+[gcc-attribute-syntax]_. Attributes allow to introduce
+implementation-defined semantics to language entities (like variables,
+functions or types) without having to make significant syntactic changes
+to the language (e.g. adding a new keyword) [n2049]_.
+
+In some cases, attributes are optional (i.e. a compiler not supporting them
+should still produce proper code, even if it is slower or does not perform
+as many compile-time checks/diagnostics).
+
+The kernel defines pseudo-keywords (e.g. ``__pure``) instead of using
+directly the GNU attribute syntax (e.g. ``__attribute__((__pure__))``)
+in order to feature detect which ones can be used and/or to shorten the code.
+
+Please refer to ``include/linux/compiler_attributes.h`` for more information.
+
+.. [c-language] http://www.open-std.org/jtc1/sc22/wg14/www/standards
+.. [gcc] https://gcc.gnu.org
+.. [clang] https://clang.llvm.org
+.. [icc] https://software.intel.com/en-us/c-compilers
+.. [gcc-c-dialect-options] https://gcc.gnu.org/onlinedocs/gcc/C-Dialect-Options.html
+.. [gnu-extensions] https://gcc.gnu.org/onlinedocs/gcc/C-Extensions.html
+.. [gcc-attribute-syntax] https://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html
+.. [n2049] http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2049.pdf
+
diff --git a/Documentation/security/keys/core.rst b/Documentation/security/keys/core.rst
index 9ce7256c6edb..9521c4207f01 100644
--- a/Documentation/security/keys/core.rst
+++ b/Documentation/security/keys/core.rst
@@ -859,6 +859,7 @@ The keyctl syscall functions are:
and either the buffer length or the OtherInfo length exceeds the
allowed length.
+
* Restrict keyring linkage::
long keyctl(KEYCTL_RESTRICT_KEYRING, key_serial_t keyring,
@@ -890,6 +891,116 @@ The keyctl syscall functions are:
applicable to the asymmetric key type.
+ * Query an asymmetric key::
+
+ long keyctl(KEYCTL_PKEY_QUERY,
+ key_serial_t key_id, unsigned long reserved,
+ struct keyctl_pkey_query *info);
+
+ Get information about an asymmetric key. The information is returned in
+ the keyctl_pkey_query struct::
+
+ __u32 supported_ops;
+ __u32 key_size;
+ __u16 max_data_size;
+ __u16 max_sig_size;
+ __u16 max_enc_size;
+ __u16 max_dec_size;
+ __u32 __spare[10];
+
+ ``supported_ops`` contains a bit mask of flags indicating which ops are
+ supported. This is constructed from a bitwise-OR of::
+
+ KEYCTL_SUPPORTS_{ENCRYPT,DECRYPT,SIGN,VERIFY}
+
+ ``key_size`` indicated the size of the key in bits.
+
+ ``max_*_size`` indicate the maximum sizes in bytes of a blob of data to be
+ signed, a signature blob, a blob to be encrypted and a blob to be
+ decrypted.
+
+ ``__spare[]`` must be set to 0. This is intended for future use to hand
+ over one or more passphrases needed unlock a key.
+
+ If successful, 0 is returned. If the key is not an asymmetric key,
+ EOPNOTSUPP is returned.
+
+
+ * Encrypt, decrypt, sign or verify a blob using an asymmetric key::
+
+ long keyctl(KEYCTL_PKEY_ENCRYPT,
+ const struct keyctl_pkey_params *params,
+ const char *info,
+ const void *in,
+ void *out);
+
+ long keyctl(KEYCTL_PKEY_DECRYPT,
+ const struct keyctl_pkey_params *params,
+ const char *info,
+ const void *in,
+ void *out);
+
+ long keyctl(KEYCTL_PKEY_SIGN,
+ const struct keyctl_pkey_params *params,
+ const char *info,
+ const void *in,
+ void *out);
+
+ long keyctl(KEYCTL_PKEY_VERIFY,
+ const struct keyctl_pkey_params *params,
+ const char *info,
+ const void *in,
+ const void *in2);
+
+ Use an asymmetric key to perform a public-key cryptographic operation a
+ blob of data. For encryption and verification, the asymmetric key may
+ only need the public parts to be available, but for decryption and signing
+ the private parts are required also.
+
+ The parameter block pointed to by params contains a number of integer
+ values::
+
+ __s32 key_id;
+ __u32 in_len;
+ __u32 out_len;
+ __u32 in2_len;
+
+ ``key_id`` is the ID of the asymmetric key to be used. ``in_len`` and
+ ``in2_len`` indicate the amount of data in the in and in2 buffers and
+ ``out_len`` indicates the size of the out buffer as appropriate for the
+ above operations.
+
+ For a given operation, the in and out buffers are used as follows::
+
+ Operation ID in,in_len out,out_len in2,in2_len
+ ======================= =============== =============== ===============
+ KEYCTL_PKEY_ENCRYPT Raw data Encrypted data -
+ KEYCTL_PKEY_DECRYPT Encrypted data Raw data -
+ KEYCTL_PKEY_SIGN Raw data Signature -
+ KEYCTL_PKEY_VERIFY Raw data - Signature
+
+ ``info`` is a string of key=value pairs that supply supplementary
+ information. These include:
+
+ ``enc=<encoding>`` The encoding of the encrypted/signature blob. This
+ can be "pkcs1" for RSASSA-PKCS1-v1.5 or
+ RSAES-PKCS1-v1.5; "pss" for "RSASSA-PSS"; "oaep" for
+ "RSAES-OAEP". If omitted or is "raw", the raw output
+ of the encryption function is specified.
+
+ ``hash=<algo>`` If the data buffer contains the output of a hash
+ function and the encoding includes some indication of
+ which hash function was used, the hash function can be
+ specified with this, eg. "hash=sha256".
+
+ The ``__spare[]`` space in the parameter block must be set to 0. This is
+ intended, amongst other things, to allow the passing of passphrases
+ required to unlock a key.
+
+ If successful, encrypt, decrypt and sign all return the amount of data
+ written into the output buffer. Verification returns 0 on success.
+
+
Kernel Services
===============
@@ -1483,6 +1594,112 @@ The structure has a number of fields, some of which are mandatory:
attempted key link operation. If there is no match, -EINVAL is returned.
+ * ``int (*asym_eds_op)(struct kernel_pkey_params *params,
+ const void *in, void *out);``
+ ``int (*asym_verify_signature)(struct kernel_pkey_params *params,
+ const void *in, const void *in2);``
+
+ These methods are optional. If provided the first allows a key to be
+ used to encrypt, decrypt or sign a blob of data, and the second allows a
+ key to verify a signature.
+
+ In all cases, the following information is provided in the params block::
+
+ struct kernel_pkey_params {
+ struct key *key;
+ const char *encoding;
+ const char *hash_algo;
+ char *info;
+ __u32 in_len;
+ union {
+ __u32 out_len;
+ __u32 in2_len;
+ };
+ enum kernel_pkey_operation op : 8;
+ };
+
+ This includes the key to be used; a string indicating the encoding to use
+ (for instance, "pkcs1" may be used with an RSA key to indicate
+ RSASSA-PKCS1-v1.5 or RSAES-PKCS1-v1.5 encoding or "raw" if no encoding);
+ the name of the hash algorithm used to generate the data for a signature
+ (if appropriate); the sizes of the input and output (or second input)
+ buffers; and the ID of the operation to be performed.
+
+ For a given operation ID, the input and output buffers are used as
+ follows::
+
+ Operation ID in,in_len out,out_len in2,in2_len
+ ======================= =============== =============== ===============
+ kernel_pkey_encrypt Raw data Encrypted data -
+ kernel_pkey_decrypt Encrypted data Raw data -
+ kernel_pkey_sign Raw data Signature -
+ kernel_pkey_verify Raw data - Signature
+
+ asym_eds_op() deals with encryption, decryption and signature creation as
+ specified by params->op. Note that params->op is also set for
+ asym_verify_signature().
+
+ Encrypting and signature creation both take raw data in the input buffer
+ and return the encrypted result in the output buffer. Padding may have
+ been added if an encoding was set. In the case of signature creation,
+ depending on the encoding, the padding created may need to indicate the
+ digest algorithm - the name of which should be supplied in hash_algo.
+
+ Decryption takes encrypted data in the input buffer and returns the raw
+ data in the output buffer. Padding will get checked and stripped off if
+ an encoding was set.
+
+ Verification takes raw data in the input buffer and the signature in the
+ second input buffer and checks that the one matches the other. Padding
+ will be validated. Depending on the encoding, the digest algorithm used
+ to generate the raw data may need to be indicated in hash_algo.
+
+ If successful, asym_eds_op() should return the number of bytes written
+ into the output buffer. asym_verify_signature() should return 0.
+
+ A variety of errors may be returned, including EOPNOTSUPP if the operation
+ is not supported; EKEYREJECTED if verification fails; ENOPKG if the
+ required crypto isn't available.
+
+
+ * ``int (*asym_query)(const struct kernel_pkey_params *params,
+ struct kernel_pkey_query *info);``
+
+ This method is optional. If provided it allows information about the
+ public or asymmetric key held in the key to be determined.
+
+ The parameter block is as for asym_eds_op() and co. but in_len and out_len
+ are unused. The encoding and hash_algo fields should be used to reduce
+ the returned buffer/data sizes as appropriate.
+
+ If successful, the following information is filled in::
+
+ struct kernel_pkey_query {
+ __u32 supported_ops;
+ __u32 key_size;
+ __u16 max_data_size;
+ __u16 max_sig_size;
+ __u16 max_enc_size;
+ __u16 max_dec_size;
+ };
+
+ The supported_ops field will contain a bitmask indicating what operations
+ are supported by the key, including encryption of a blob, decryption of a
+ blob, signing a blob and verifying the signature on a blob. The following
+ constants are defined for this::
+
+ KEYCTL_SUPPORTS_{ENCRYPT,DECRYPT,SIGN,VERIFY}
+
+ The key_size field is the size of the key in bits. max_data_size and
+ max_sig_size are the maximum raw data and signature sizes for creation and
+ verification of a signature; max_enc_size and max_dec_size are the maximum
+ raw data and signature sizes for encryption and decryption. The
+ max_*_size fields are measured in bytes.
+
+ If successful, 0 will be returned. If the key doesn't support this,
+ EOPNOTSUPP will be returned.
+
+
Request-Key Callback Service
============================
diff --git a/Documentation/security/self-protection.rst b/Documentation/security/self-protection.rst
index e1ca698e0006..f584fb74b4ff 100644
--- a/Documentation/security/self-protection.rst
+++ b/Documentation/security/self-protection.rst
@@ -302,11 +302,11 @@ sure structure holes are cleared.
Memory poisoning
----------------
-When releasing memory, it is best to poison the contents (clear stack on
-syscall return, wipe heap memory on a free), to avoid reuse attacks that
-rely on the old contents of memory. This frustrates many uninitialized
-variable attacks, stack content exposures, heap content exposures, and
-use-after-free attacks.
+When releasing memory, it is best to poison the contents, to avoid reuse
+attacks that rely on the old contents of memory. E.g., clear stack on a
+syscall return (``CONFIG_GCC_PLUGIN_STACKLEAK``), wipe heap memory on a
+free. This frustrates many uninitialized variable attacks, stack content
+exposures, heap content exposures, and use-after-free attacks.
Destination tracking
--------------------
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index 37a679501ddc..1b8775298cf7 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -89,6 +89,7 @@ show up in /proc/sys/kernel:
- shmmni
- softlockup_all_cpu_backtrace
- soft_watchdog
+- stack_erasing
- stop-a [ SPARC only ]
- sysrq ==> Documentation/admin-guide/sysrq.rst
- sysctl_writes_strict
@@ -987,6 +988,23 @@ detect a hard lockup condition.
==============================================================
+stack_erasing
+
+This parameter can be used to control kernel stack erasing at the end
+of syscalls for kernels built with CONFIG_GCC_PLUGIN_STACKLEAK.
+
+That erasing reduces the information which kernel stack leak bugs
+can reveal and blocks some uninitialized stack variable attacks.
+The tradeoff is the performance impact: on a single CPU system kernel
+compilation sees a 1% slowdown, other systems and workloads may vary.
+
+ 0: kernel stack erasing is disabled, STACKLEAK_METRICS are not updated.
+
+ 1: kernel stack erasing is enabled (default), it is performed before
+ returning to the userspace at the end of syscalls.
+
+==============================================================
+
tainted:
Non-zero if the kernel has been tainted. Numeric values, which can be
diff --git a/Documentation/x86/x86_64/mm.txt b/Documentation/x86/x86_64/mm.txt
index 702898633b00..804f9426ed17 100644
--- a/Documentation/x86/x86_64/mm.txt
+++ b/Documentation/x86/x86_64/mm.txt
@@ -34,23 +34,24 @@ __________________|____________|__________________|_________|___________________
____________________________________________________________|___________________________________________________________
| | | |
ffff800000000000 | -128 TB | ffff87ffffffffff | 8 TB | ... guard hole, also reserved for hypervisor
- ffff880000000000 | -120 TB | ffffc7ffffffffff | 64 TB | direct mapping of all physical memory (page_offset_base)
- ffffc80000000000 | -56 TB | ffffc8ffffffffff | 1 TB | ... unused hole
+ ffff880000000000 | -120 TB | ffff887fffffffff | 0.5 TB | LDT remap for PTI
+ ffff888000000000 | -119.5 TB | ffffc87fffffffff | 64 TB | direct mapping of all physical memory (page_offset_base)
+ ffffc88000000000 | -55.5 TB | ffffc8ffffffffff | 0.5 TB | ... unused hole
ffffc90000000000 | -55 TB | ffffe8ffffffffff | 32 TB | vmalloc/ioremap space (vmalloc_base)
ffffe90000000000 | -23 TB | ffffe9ffffffffff | 1 TB | ... unused hole
ffffea0000000000 | -22 TB | ffffeaffffffffff | 1 TB | virtual memory map (vmemmap_base)
ffffeb0000000000 | -21 TB | ffffebffffffffff | 1 TB | ... unused hole
ffffec0000000000 | -20 TB | fffffbffffffffff | 16 TB | KASAN shadow memory
- fffffc0000000000 | -4 TB | fffffdffffffffff | 2 TB | ... unused hole
- | | | | vaddr_end for KASLR
- fffffe0000000000 | -2 TB | fffffe7fffffffff | 0.5 TB | cpu_entry_area mapping
- fffffe8000000000 | -1.5 TB | fffffeffffffffff | 0.5 TB | LDT remap for PTI
- ffffff0000000000 | -1 TB | ffffff7fffffffff | 0.5 TB | %esp fixup stacks
__________________|____________|__________________|_________|____________________________________________________________
|
- | Identical layout to the 47-bit one from here on:
+ | Identical layout to the 56-bit one from here on:
____________________________________________________________|____________________________________________________________
| | | |
+ fffffc0000000000 | -4 TB | fffffdffffffffff | 2 TB | ... unused hole
+ | | | | vaddr_end for KASLR
+ fffffe0000000000 | -2 TB | fffffe7fffffffff | 0.5 TB | cpu_entry_area mapping
+ fffffe8000000000 | -1.5 TB | fffffeffffffffff | 0.5 TB | ... unused hole
+ ffffff0000000000 | -1 TB | ffffff7fffffffff | 0.5 TB | %esp fixup stacks
ffffff8000000000 | -512 GB | ffffffeeffffffff | 444 GB | ... unused hole
ffffffef00000000 | -68 GB | fffffffeffffffff | 64 GB | EFI region mapping space
ffffffff00000000 | -4 GB | ffffffff7fffffff | 2 GB | ... unused hole
@@ -83,7 +84,7 @@ Notes:
__________________|____________|__________________|_________|___________________________________________________________
| | | |
0000800000000000 | +64 PB | ffff7fffffffffff | ~16K PB | ... huge, still almost 64 bits wide hole of non-canonical
- | | | | virtual memory addresses up to the -128 TB
+ | | | | virtual memory addresses up to the -64 PB
| | | | starting offset of kernel mappings.
__________________|____________|__________________|_________|___________________________________________________________
|
@@ -91,23 +92,24 @@ __________________|____________|__________________|_________|___________________
____________________________________________________________|___________________________________________________________
| | | |
ff00000000000000 | -64 PB | ff0fffffffffffff | 4 PB | ... guard hole, also reserved for hypervisor
- ff10000000000000 | -60 PB | ff8fffffffffffff | 32 PB | direct mapping of all physical memory (page_offset_base)
- ff90000000000000 | -28 PB | ff9fffffffffffff | 4 PB | LDT remap for PTI
+ ff10000000000000 | -60 PB | ff10ffffffffffff | 0.25 PB | LDT remap for PTI
+ ff11000000000000 | -59.75 PB | ff90ffffffffffff | 32 PB | direct mapping of all physical memory (page_offset_base)
+ ff91000000000000 | -27.75 PB | ff9fffffffffffff | 3.75 PB | ... unused hole
ffa0000000000000 | -24 PB | ffd1ffffffffffff | 12.5 PB | vmalloc/ioremap space (vmalloc_base)
ffd2000000000000 | -11.5 PB | ffd3ffffffffffff | 0.5 PB | ... unused hole
ffd4000000000000 | -11 PB | ffd5ffffffffffff | 0.5 PB | virtual memory map (vmemmap_base)
ffd6000000000000 | -10.5 PB | ffdeffffffffffff | 2.25 PB | ... unused hole
ffdf000000000000 | -8.25 PB | fffffdffffffffff | ~8 PB | KASAN shadow memory
- fffffc0000000000 | -4 TB | fffffdffffffffff | 2 TB | ... unused hole
- | | | | vaddr_end for KASLR
- fffffe0000000000 | -2 TB | fffffe7fffffffff | 0.5 TB | cpu_entry_area mapping
- fffffe8000000000 | -1.5 TB | fffffeffffffffff | 0.5 TB | ... unused hole
- ffffff0000000000 | -1 TB | ffffff7fffffffff | 0.5 TB | %esp fixup stacks
__________________|____________|__________________|_________|____________________________________________________________
|
| Identical layout to the 47-bit one from here on:
____________________________________________________________|____________________________________________________________
| | | |
+ fffffc0000000000 | -4 TB | fffffdffffffffff | 2 TB | ... unused hole
+ | | | | vaddr_end for KASLR
+ fffffe0000000000 | -2 TB | fffffe7fffffffff | 0.5 TB | cpu_entry_area mapping
+ fffffe8000000000 | -1.5 TB | fffffeffffffffff | 0.5 TB | ... unused hole
+ ffffff0000000000 | -1 TB | ffffff7fffffffff | 0.5 TB | %esp fixup stacks
ffffff8000000000 | -512 GB | ffffffeeffffffff | 444 GB | ... unused hole
ffffffef00000000 | -68 GB | fffffffeffffffff | 64 GB | EFI region mapping space
ffffffff00000000 | -4 GB | ffffffff7fffffff | 2 GB | ... unused hole
@@ -146,3 +148,6 @@ Their order is preserved but their base will be offset early at boot time.
Be very careful vs. KASLR when changing anything here. The KASLR address
range must not overlap with anything except the KASAN shadow area, which is
correct as KASAN disables KASLR.
+
+For both 4- and 5-level layouts, the STACKLEAK_POISON value in the last 2MB
+hole: ffffffffffff4111
diff --git a/Documentation/x86/zero-page.txt b/Documentation/x86/zero-page.txt
index 97b7adbceda4..68aed077f7b6 100644
--- a/Documentation/x86/zero-page.txt
+++ b/Documentation/x86/zero-page.txt
@@ -25,7 +25,7 @@ Offset Proto Name Meaning
0C8/004 ALL ext_cmd_line_ptr cmd_line_ptr high 32bits
140/080 ALL edid_info Video mode setup (struct edid_info)
1C0/020 ALL efi_info EFI 32 information (struct efi_info)
-1E0/004 ALL alk_mem_k Alternative mem check, in KB
+1E0/004 ALL alt_mem_k Alternative mem check, in KB
1E4/004 ALL scratch Scratch field for the kernel setup code
1E8/001 ALL e820_entries Number of entries in e820_table (below)
1E9/001 ALL eddbuf_entries Number of entries in eddbuf (below)