diff options
Diffstat (limited to 'Documentation')
18 files changed, 263 insertions, 130 deletions
diff --git a/Documentation/ABI/testing/sysfs-block-rssd b/Documentation/ABI/testing/sysfs-block-rssd index 679ce35..beef30c 100644 --- a/Documentation/ABI/testing/sysfs-block-rssd +++ b/Documentation/ABI/testing/sysfs-block-rssd @@ -1,26 +1,5 @@ -What: /sys/block/rssd*/registers -Date: March 2012 -KernelVersion: 3.3 -Contact: Asai Thambi S P <asamymuthupa@micron.com> -Description: This is a read-only file. Dumps below driver information and - hardware registers. - - S ACTive - - Command Issue - - Completed - - PORT IRQ STAT - - HOST IRQ STAT - - Allocated - - Commands in Q - What: /sys/block/rssd*/status Date: April 2012 KernelVersion: 3.4 Contact: Asai Thambi S P <asamymuthupa@micron.com> Description: This is a read-only file. Indicates the status of the device. - -What: /sys/block/rssd*/flags -Date: May 2012 -KernelVersion: 3.5 -Contact: Asai Thambi S P <asamymuthupa@micron.com> -Description: This is a read-only file. Dumps the flags in port and driver - data structure diff --git a/Documentation/ABI/testing/sysfs-class-mtd b/Documentation/ABI/testing/sysfs-class-mtd index db1ad7e..938ef71 100644 --- a/Documentation/ABI/testing/sysfs-class-mtd +++ b/Documentation/ABI/testing/sysfs-class-mtd @@ -142,13 +142,14 @@ KernelVersion: 3.4 Contact: linux-mtd@lists.infradead.org Description: This allows the user to examine and adjust the criteria by which - mtd returns -EUCLEAN from mtd_read(). If the maximum number of - bit errors that were corrected on any single region comprising - an ecc step (as reported by the driver) equals or exceeds this - value, -EUCLEAN is returned. Otherwise, absent an error, 0 is - returned. Higher layers (e.g., UBI) use this return code as an - indication that an erase block may be degrading and should be - scrutinized as a candidate for being marked as bad. + mtd returns -EUCLEAN from mtd_read() and mtd_read_oob(). If the + maximum number of bit errors that were corrected on any single + region comprising an ecc step (as reported by the driver) equals + or exceeds this value, -EUCLEAN is returned. Otherwise, absent + an error, 0 is returned. Higher layers (e.g., UBI) use this + return code as an indication that an erase block may be + degrading and should be scrutinized as a candidate for being + marked as bad. The initial value may be specified by the flash device driver. If not, then the default value is ecc_strength. @@ -167,7 +168,7 @@ Description: block degradation, but high enough to avoid the consequences of a persistent return value of -EUCLEAN on devices where sticky bitflips occur. Note that if bitflip_threshold exceeds - ecc_strength, -EUCLEAN is never returned by mtd_read(). + ecc_strength, -EUCLEAN is never returned by the read operations. Conversely, if bitflip_threshold is zero, -EUCLEAN is always returned, absent a hard error. diff --git a/Documentation/ABI/testing/sysfs-driver-hid-lenovo-tpkbd b/Documentation/ABI/testing/sysfs-driver-hid-lenovo-tpkbd new file mode 100644 index 0000000..57b92cb --- /dev/null +++ b/Documentation/ABI/testing/sysfs-driver-hid-lenovo-tpkbd @@ -0,0 +1,38 @@ +What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/press_to_select +Date: July 2011 +Contact: linux-input@vger.kernel.org +Description: This controls if mouse clicks should be generated if the trackpoint is quickly pressed. How fast this press has to be + is being controlled by press_speed. + Values are 0 or 1. + +What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/dragging +Date: July 2011 +Contact: linux-input@vger.kernel.org +Description: If this setting is enabled, it is possible to do dragging by pressing the trackpoint. This requires press_to_select to be enabled. + Values are 0 or 1. + +What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/release_to_select +Date: July 2011 +Contact: linux-input@vger.kernel.org +Description: For details regarding this setting please refer to http://www.pc.ibm.com/ww/healthycomputing/trkpntb.html + Values are 0 or 1. + +What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/select_right +Date: July 2011 +Contact: linux-input@vger.kernel.org +Description: This setting controls if the mouse click events generated by pressing the trackpoint (if press_to_select is enabled) generate + a left or right mouse button click. + Values are 0 or 1. + +What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/sensitivity +Date: July 2011 +Contact: linux-input@vger.kernel.org +Description: This file contains the trackpoint sensitivity. + Values are decimal integers from 1 (lowest sensitivity) to 255 (highest sensitivity). + +What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/press_speed +Date: July 2011 +Contact: linux-input@vger.kernel.org +Description: This setting controls how fast the trackpoint needs to be pressed to generate a mouse click if press_to_select is enabled. + Values are decimal integers from 1 (slowest) to 255 (fastest). + diff --git a/Documentation/ABI/testing/sysfs-driver-hid-roccat-savu b/Documentation/ABI/testing/sysfs-driver-hid-roccat-savu new file mode 100644 index 0000000..b42922c --- /dev/null +++ b/Documentation/ABI/testing/sysfs-driver-hid-roccat-savu @@ -0,0 +1,77 @@ +What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/savu/roccatsavu<minor>/buttons +Date: Mai 2012 +Contact: Stefan Achatz <erazor_de@users.sourceforge.net> +Description: The mouse can store 5 profiles which can be switched by the + press of a button. A profile is split into general settings and + button settings. buttons holds informations about button layout. + When written, this file lets one write the respective profile + buttons to the mouse. The data has to be 47 bytes long. + The mouse will reject invalid data. + Which profile to write is determined by the profile number + contained in the data. + Before reading this file, control has to be written to select + which profile to read. +Users: http://roccat.sourceforge.net + +What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/savu/roccatsavu<minor>/control +Date: Mai 2012 +Contact: Stefan Achatz <erazor_de@users.sourceforge.net> +Description: When written, this file lets one select which data from which + profile will be read next. The data has to be 3 bytes long. + This file is writeonly. +Users: http://roccat.sourceforge.net + +What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/savu/roccatsavu<minor>/general +Date: Mai 2012 +Contact: Stefan Achatz <erazor_de@users.sourceforge.net> +Description: The mouse can store 5 profiles which can be switched by the + press of a button. A profile is split into general settings and + button settings. profile holds informations like resolution, sensitivity + and light effects. + When written, this file lets one write the respective profile + settings back to the mouse. The data has to be 43 bytes long. + The mouse will reject invalid data. + Which profile to write is determined by the profile number + contained in the data. + This file is writeonly. +Users: http://roccat.sourceforge.net + +What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/savu/roccatsavu<minor>/info +Date: Mai 2012 +Contact: Stefan Achatz <erazor_de@users.sourceforge.net> +Description: When read, this file returns general data like firmware version. + The data is 8 bytes long. + This file is readonly. +Users: http://roccat.sourceforge.net + +What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/savu/roccatsavu<minor>/macro +Date: Mai 2012 +Contact: Stefan Achatz <erazor_de@users.sourceforge.net> +Description: When written, this file lets one store macros with max 500 + keystrokes for a specific button for a specific profile. + Button and profile numbers are included in written data. + The data has to be 2083 bytes long. + Before reading this file, control has to be written to select + which profile and key to read. +Users: http://roccat.sourceforge.net + +What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/savu/roccatsavu<minor>/profile +Date: Mai 2012 +Contact: Stefan Achatz <erazor_de@users.sourceforge.net> +Description: The mouse can store 5 profiles which can be switched by the + press of a button. profile holds number of actual profile. + This value is persistent, so its value determines the profile + that's active when the mouse is powered on next time. + When written, the mouse activates the set profile immediately. + The data has to be 3 bytes long. + The mouse will reject invalid data. +Users: http://roccat.sourceforge.net + +What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/savu/roccatsavu<minor>/sensor +Date: July 2012 +Contact: Stefan Achatz <erazor_de@users.sourceforge.net> +Description: The mouse has a Avago ADNS-3090 sensor. + This file allows reading and writing of the mouse sensors registers. + The data has to be 4 bytes long. +Users: http://roccat.sourceforge.net + diff --git a/Documentation/DocBook/media/v4l/controls.xml b/Documentation/DocBook/media/v4l/controls.xml index 676bc46..cda0dfb 100644 --- a/Documentation/DocBook/media/v4l/controls.xml +++ b/Documentation/DocBook/media/v4l/controls.xml @@ -3988,7 +3988,7 @@ interface and may change in the future.</para> from RGB to Y'CbCr color space. </entry> </row> - <row id = "v4l2-jpeg-chroma-subsampling"> + <row> <entrytbl spanname="descr" cols="2"> <tbody valign="top"> <row> diff --git a/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml b/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml index e3d5afcd..0a4b90f 100644 --- a/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml +++ b/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml @@ -284,13 +284,6 @@ These controls are described in <xref processing controls. These controls are described in <xref linkend="image-process-controls" />.</entry> </row> - <row> - <entry><constant>V4L2_CTRL_CLASS_JPEG</constant></entry> - <entry>0x9d0000</entry> - <entry>The class containing JPEG compression controls. -These controls are described in <xref - linkend="jpeg-controls" />.</entry> - </row> </tbody> </tgroup> </table> diff --git a/Documentation/device-mapper/verity.txt b/Documentation/device-mapper/verity.txt index 32e4879..9884681 100644 --- a/Documentation/device-mapper/verity.txt +++ b/Documentation/device-mapper/verity.txt @@ -7,39 +7,39 @@ This target is read-only. Construction Parameters ======================= - <version> <dev> <hash_dev> <hash_start> + <version> <dev> <hash_dev> <data_block_size> <hash_block_size> <num_data_blocks> <hash_start_block> <algorithm> <digest> <salt> <version> - This is the version number of the on-disk format. + This is the type of the on-disk hash format. 0 is the original format used in the Chromium OS. - The salt is appended when hashing, digests are stored continuously and - the rest of the block is padded with zeros. + The salt is appended when hashing, digests are stored continuously and + the rest of the block is padded with zeros. 1 is the current format that should be used for new devices. - The salt is prepended when hashing and each digest is - padded with zeros to the power of two. + The salt is prepended when hashing and each digest is + padded with zeros to the power of two. <dev> - This is the device containing the data the integrity of which needs to be + This is the device containing data, the integrity of which needs to be checked. It may be specified as a path, like /dev/sdaX, or a device number, <major>:<minor>. <hash_dev> - This is the device that that supplies the hash tree data. It may be + This is the device that supplies the hash tree data. It may be specified similarly to the device path and may be the same device. If the - same device is used, the hash_start should be outside of the dm-verity - configured device size. + same device is used, the hash_start should be outside the configured + dm-verity device. <data_block_size> - The block size on a data device. Each block corresponds to one digest on - the hash device. + The block size on a data device in bytes. + Each block corresponds to one digest on the hash device. <hash_block_size> - The size of a hash block. + The size of a hash block in bytes. <num_data_blocks> The number of data blocks on the data device. Additional blocks are @@ -65,7 +65,7 @@ Construction Parameters Theory of operation =================== -dm-verity is meant to be setup as part of a verified boot path. This +dm-verity is meant to be set up as part of a verified boot path. This may be anything ranging from a boot using tboot or trustedgrub to just booting from a known-good device (like a USB drive or CD). @@ -73,20 +73,20 @@ When a dm-verity device is configured, it is expected that the caller has been authenticated in some way (cryptographic signatures, etc). After instantiation, all hashes will be verified on-demand during disk access. If they cannot be verified up to the root node of the -tree, the root hash, then the I/O will fail. This should identify +tree, the root hash, then the I/O will fail. This should detect tampering with any data on the device and the hash data. Cryptographic hashes are used to assert the integrity of the device on a -per-block basis. This allows for a lightweight hash computation on first read -into the page cache. Block hashes are stored linearly-aligned to the nearest -block the size of a page. +per-block basis. This allows for a lightweight hash computation on first read +into the page cache. Block hashes are stored linearly, aligned to the nearest +block size. Hash Tree --------- Each node in the tree is a cryptographic hash. If it is a leaf node, the hash -is of some block data on disk. If it is an intermediary node, then the hash is -of a number of child nodes. +of some data block on disk is calculated. If it is an intermediary node, +the hash of a number of child nodes is calculated. Each entry in the tree is a collection of neighboring nodes that fit in one block. The number is determined based on block_size and the size of the @@ -110,63 +110,23 @@ alg = sha256, num_blocks = 32768, block_size = 4096 On-disk format ============== -Below is the recommended on-disk format. The verity kernel code does not -read the on-disk header. It only reads the hash blocks which directly -follow the header. It is expected that a user-space tool will verify the -integrity of the verity_header and then call dmsetup with the correct -parameters. Alternatively, the header can be omitted and the dmsetup -parameters can be passed via the kernel command-line in a rooted chain -of trust where the command-line is verified. +The verity kernel code does not read the verity metadata on-disk header. +It only reads the hash blocks which directly follow the header. +It is expected that a user-space tool will verify the integrity of the +verity header. -The on-disk format is especially useful in cases where the hash blocks -are on a separate partition. The magic number allows easy identification -of the partition contents. Alternatively, the hash blocks can be stored -in the same partition as the data to be verified. In such a configuration -the filesystem on the partition would be sized a little smaller than -the full-partition, leaving room for the hash blocks. - -struct superblock { - uint8_t signature[8] - "verity\0\0"; - - uint8_t version; - 1 - current format - - uint8_t data_block_bits; - log2(data block size) - - uint8_t hash_block_bits; - log2(hash block size) - - uint8_t pad1[1]; - zero padding - - uint16_t salt_size; - big-endian salt size - - uint8_t pad2[2]; - zero padding - - uint32_t data_blocks_hi; - big-endian high 32 bits of the 64-bit number of data blocks - - uint32_t data_blocks_lo; - big-endian low 32 bits of the 64-bit number of data blocks - - uint8_t algorithm[16]; - cryptographic algorithm - - uint8_t salt[384]; - salt (the salt size is specified above) - - uint8_t pad3[88]; - zero padding to 512-byte boundary -} +Alternatively, the header can be omitted and the dmsetup parameters can +be passed via the kernel command-line in a rooted chain of trust where +the command-line is verified. Directly following the header (and with sector number padded to the next hash block boundary) are the hash blocks which are stored a depth at a time (starting from the root), sorted in order of increasing index. +The full specification of kernel parameters and on-disk metadata format +is available at the cryptsetup project's wiki page + http://code.google.com/p/cryptsetup/wiki/DMVerity + Status ====== V (for Valid) is returned if every check performed so far was valid. @@ -174,21 +134,22 @@ If any check failed, C (for Corruption) is returned. Example ======= - -Setup a device: - dmsetup create vroot --table \ - "0 2097152 "\ - "verity 1 /dev/sda1 /dev/sda2 4096 4096 2097152 1 "\ +Set up a device: + # dmsetup create vroot --readonly --table \ + "0 2097152 verity 1 /dev/sda1 /dev/sda2 4096 4096 262144 1 sha256 "\ "4392712ba01368efdf14b05c76f9e4df0d53664630b5d48632ed17a137f39076 "\ "1234000000000000000000000000000000000000000000000000000000000000" A command line tool veritysetup is available to compute or verify -the hash tree or activate the kernel driver. This is available from -the LVM2 upstream repository and may be supplied as a package called -device-mapper-verity-tools: - git://sources.redhat.com/git/lvm2 - http://sourceware.org/git/?p=lvm2.git - http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/verity?cvsroot=lvm2 - -veritysetup -a vroot /dev/sda1 /dev/sda2 \ - 4392712ba01368efdf14b05c76f9e4df0d53664630b5d48632ed17a137f39076 +the hash tree or activate the kernel device. This is available from +the cryptsetup upstream repository http://code.google.com/p/cryptsetup/ +(as a libcryptsetup extension). + +Create hash on the device: + # veritysetup format /dev/sda1 /dev/sda2 + ... + Root hash: 4392712ba01368efdf14b05c76f9e4df0d53664630b5d48632ed17a137f39076 + +Activate the device: + # veritysetup create vroot /dev/sda1 /dev/sda2 \ + 4392712ba01368efdf14b05c76f9e4df0d53664630b5d48632ed17a137f39076 diff --git a/Documentation/devicetree/bindings/input/fsl-mma8450.txt b/Documentation/devicetree/bindings/input/fsl-mma8450.txt index a00c94c..0b96e57 100644 --- a/Documentation/devicetree/bindings/input/fsl-mma8450.txt +++ b/Documentation/devicetree/bindings/input/fsl-mma8450.txt @@ -2,6 +2,7 @@ Required properties: - compatible : "fsl,mma8450". +- reg: the I2C address of MMA8450 Example: diff --git a/Documentation/devicetree/bindings/mfd/mc13xxx.txt b/Documentation/devicetree/bindings/mfd/mc13xxx.txt index 19f6af4..baf0798 100644 --- a/Documentation/devicetree/bindings/mfd/mc13xxx.txt +++ b/Documentation/devicetree/bindings/mfd/mc13xxx.txt @@ -46,8 +46,8 @@ Examples: ecspi@70010000 { /* ECSPI1 */ fsl,spi-num-chipselects = <2>; - cs-gpios = <&gpio3 24 0>, /* GPIO4_24 */ - <&gpio3 25 0>; /* GPIO4_25 */ + cs-gpios = <&gpio4 24 0>, /* GPIO4_24 */ + <&gpio4 25 0>; /* GPIO4_25 */ status = "okay"; pmic: mc13892@0 { diff --git a/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt b/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt index c7e404b..fea541e 100644 --- a/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt +++ b/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt @@ -29,6 +29,6 @@ esdhc@70008000 { compatible = "fsl,imx51-esdhc"; reg = <0x70008000 0x4000>; interrupts = <2>; - cd-gpios = <&gpio0 6 0>; /* GPIO1_6 */ - wp-gpios = <&gpio0 5 0>; /* GPIO1_5 */ + cd-gpios = <&gpio1 6 0>; /* GPIO1_6 */ + wp-gpios = <&gpio1 5 0>; /* GPIO1_5 */ }; diff --git a/Documentation/devicetree/bindings/net/fsl-fec.txt b/Documentation/devicetree/bindings/net/fsl-fec.txt index 7ab9e1a..4616fc2 100644 --- a/Documentation/devicetree/bindings/net/fsl-fec.txt +++ b/Documentation/devicetree/bindings/net/fsl-fec.txt @@ -19,6 +19,6 @@ ethernet@83fec000 { reg = <0x83fec000 0x4000>; interrupts = <87>; phy-mode = "mii"; - phy-reset-gpios = <&gpio1 14 0>; /* GPIO2_14 */ + phy-reset-gpios = <&gpio2 14 0>; /* GPIO2_14 */ local-mac-address = [00 04 9F 01 1B B9]; }; diff --git a/Documentation/devicetree/bindings/pinctrl/fsl,imx6q-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/fsl,imx6q-pinctrl.txt index 82b43f9..a4119f6 100644 --- a/Documentation/devicetree/bindings/pinctrl/fsl,imx6q-pinctrl.txt +++ b/Documentation/devicetree/bindings/pinctrl/fsl,imx6q-pinctrl.txt @@ -1626,3 +1626,5 @@ MX6Q_PAD_SD2_DAT3__PCIE_CTRL_MUX_11 1587 MX6Q_PAD_SD2_DAT3__GPIO_1_12 1588 MX6Q_PAD_SD2_DAT3__SJC_DONE 1589 MX6Q_PAD_SD2_DAT3__ANATOP_TESTO_3 1590 +MX6Q_PAD_ENET_RX_ER__ANATOP_USBOTG_ID 1591 +MX6Q_PAD_GPIO_1__ANATOP_USBOTG_ID 1592 diff --git a/Documentation/devicetree/bindings/spi/fsl-imx-cspi.txt b/Documentation/devicetree/bindings/spi/fsl-imx-cspi.txt index 9841057..4256a6d 100644 --- a/Documentation/devicetree/bindings/spi/fsl-imx-cspi.txt +++ b/Documentation/devicetree/bindings/spi/fsl-imx-cspi.txt @@ -17,6 +17,6 @@ ecspi@70010000 { reg = <0x70010000 0x4000>; interrupts = <36>; fsl,spi-num-chipselects = <2>; - cs-gpios = <&gpio3 24 0>, /* GPIO4_24 */ - <&gpio3 25 0>; /* GPIO4_25 */ + cs-gpios = <&gpio3 24 0>, /* GPIO3_24 */ + <&gpio3 25 0>; /* GPIO3_25 */ }; diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt index 6eab917..db4d3af 100644 --- a/Documentation/devicetree/bindings/vendor-prefixes.txt +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt @@ -3,6 +3,7 @@ Device tree binding vendor prefix registry. Keep list in alphabetical order. This isn't an exhaustive list, but you should add new prefixes to it before using them to avoid name-space collisions. +ad Avionic Design GmbH adi Analog Devices, Inc. amcc Applied Micro Circuits Corporation (APM, formally AMCC) apm Applied Micro Circuits Corporation (APM) diff --git a/Documentation/kdump/kdump.txt b/Documentation/kdump/kdump.txt index 506c739..13f1aa0 100644 --- a/Documentation/kdump/kdump.txt +++ b/Documentation/kdump/kdump.txt @@ -86,7 +86,7 @@ There is also a gitweb interface available at http://www.kernel.org/git/?p=utils/kernel/kexec/kexec-tools.git More information about kexec-tools can be found at -http://www.kernel.org/pub/linux/utils/kernel/kexec/README.html +http://horms.net/projects/kexec/ 3) Unpack the tarball with the tar command, as follows: diff --git a/Documentation/prctl/no_new_privs.txt b/Documentation/prctl/no_new_privs.txt new file mode 100644 index 0000000..f7be84f --- /dev/null +++ b/Documentation/prctl/no_new_privs.txt @@ -0,0 +1,57 @@ +The execve system call can grant a newly-started program privileges that +its parent did not have. The most obvious examples are setuid/setgid +programs and file capabilities. To prevent the parent program from +gaining these privileges as well, the kernel and user code must be +careful to prevent the parent from doing anything that could subvert the +child. For example: + + - The dynamic loader handles LD_* environment variables differently if + a program is setuid. + + - chroot is disallowed to unprivileged processes, since it would allow + /etc/passwd to be replaced from the point of view of a process that + inherited chroot. + + - The exec code has special handling for ptrace. + +These are all ad-hoc fixes. The no_new_privs bit (since Linux 3.5) is a +new, generic mechanism to make it safe for a process to modify its +execution environment in a manner that persists across execve. Any task +can set no_new_privs. Once the bit is set, it is inherited across fork, +clone, and execve and cannot be unset. With no_new_privs set, execve +promises not to grant the privilege to do anything that could not have +been done without the execve call. For example, the setuid and setgid +bits will no longer change the uid or gid; file capabilities will not +add to the permitted set, and LSMs will not relax constraints after +execve. + +To set no_new_privs, use prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0). + +Be careful, though: LSMs might also not tighten constraints on exec +in no_new_privs mode. (This means that setting up a general-purpose +service launcher to set no_new_privs before execing daemons may +interfere with LSM-based sandboxing.) + +Note that no_new_privs does not prevent privilege changes that do not +involve execve. An appropriately privileged task can still call +setuid(2) and receive SCM_RIGHTS datagrams. + +There are two main use cases for no_new_privs so far: + + - Filters installed for the seccomp mode 2 sandbox persist across + execve and can change the behavior of newly-executed programs. + Unprivileged users are therefore only allowed to install such filters + if no_new_privs is set. + + - By itself, no_new_privs can be used to reduce the attack surface + available to an unprivileged user. If everything running with a + given uid has no_new_privs set, then that uid will be unable to + escalate its privileges by directly attacking setuid, setgid, and + fcap-using binaries; it will need to compromise something without the + no_new_privs bit set first. + +In the future, other potentially dangerous kernel features could become +available to unprivileged tasks if no_new_privs is set. In principle, +several options to unshare(2) and clone(2) would be safe when +no_new_privs is set, and no_new_privs + chroot is considerable less +dangerous than chroot by itself. diff --git a/Documentation/stable_kernel_rules.txt b/Documentation/stable_kernel_rules.txt index f0ab5cf..4a7b54b 100644 --- a/Documentation/stable_kernel_rules.txt +++ b/Documentation/stable_kernel_rules.txt @@ -12,6 +12,12 @@ Rules on what kind of patches are accepted, and which ones are not, into the marked CONFIG_BROKEN), an oops, a hang, data corruption, a real security issue, or some "oh, that's not good" issue. In short, something critical. + - Serious issues as reported by a user of a distribution kernel may also + be considered if they fix a notable performance or interactivity issue. + As these fixes are not as obvious and have a higher risk of a subtle + regression they should only be submitted by a distribution kernel + maintainer and include an addendum linking to a bugzilla entry if it + exists and additional information on the user-visible impact. - New device IDs and quirks are also accepted. - No "theoretical race condition" issues, unless an explanation of how the race can be exploited is also provided. diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 9301266..2c99483 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -1930,6 +1930,23 @@ The "pte_enc" field provides a value that can OR'ed into the hash PTE's RPN field (ie, it needs to be shifted left by 12 to OR it into the hash PTE second double word). +4.75 KVM_IRQFD + +Capability: KVM_CAP_IRQFD +Architectures: x86 +Type: vm ioctl +Parameters: struct kvm_irqfd (in) +Returns: 0 on success, -1 on error + +Allows setting an eventfd to directly trigger a guest interrupt. +kvm_irqfd.fd specifies the file descriptor to use as the eventfd and +kvm_irqfd.gsi specifies the irqchip pin toggled by this event. When +an event is tiggered on the eventfd, an interrupt is injected into +the guest using the specified gsi pin. The irqfd is removed using +the KVM_IRQFD_FLAG_DEASSIGN flag, specifying both kvm_irqfd.fd +and kvm_irqfd.gsi. + + 5. The kvm_run structure ------------------------ |