Measuring keys requires a custom IMA policy to be loaded.  Keys should
be queued for measurement if a custom IMA policy is not yet loaded.
Keys queued for measurement, if any, should be processed when a custom
policy is loaded.

This patch updates the IMA hook function ima_post_key_create_or_update()
to queue the key if a custom IMA policy has not yet been loaded.  And,
ima_update_policy() function, which is called when a custom IMA policy
is loaded, is updated to process queued keys.
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

Measuring keys requires a custom IMA policy to be loaded.  Keys created
or updated before a custom IMA policy is loaded should be queued and
will be processed after a custom policy is loaded.

This patch defines a workqueue for queuing keys when a custom IMA policy
has not yet been loaded.  An intermediate Kconfig boolean option namely
IMA_QUEUE_EARLY_BOOT_KEYS is used to declare the workqueue functions.

A flag namely ima_process_keys is used to check if the key should be
queued or should be processed immediately.
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

ima_match_keyring() is called while holding rcu read lock. Since this
function executes in atomic context, it should not call any function
that can sleep (such as kstrdup()).

This patch pre-allocates a buffer to hold the keyrings string read from
the IMA policy and uses that to match the given keyring.
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Fixes: e9085e0a ("IMA: Add support to limit measuring keys")
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

Keep the ima policy rules around from the beginning even if they appear
invalid at the time of loading, as they may become active after an lsm
policy load.  However, loading a custom IMA policy with unknown LSM
labels is only safe after we have transitioned from the "built-in"
policy rules to a custom IMA policy.

Patch also fixes the rule re-use during the lsm policy reload and makes
some prints a bit more human readable.

Changelog:
v4:
- Do not allow the initial policy load refer to non-existing lsm rules.
v3:
- Fix too wide policy rule matching for non-initialized LSMs
v2:
- Fix log prints

Fixes: b1694245 ("ima: use the lsm policy update notifier")
Cc: Casey Schaufler <casey@schaufler-ca.com>
Reported-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Janne Karhunen <janne.karhunen@gmail.com>
Signed-off-by: Konsta Karsisto <konsta.karsisto@gmail.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

This allows other parts of the kernel (perhaps a stacked LSM allowing
system monitoring, eg. the proposed KRSI LSM [1]) to retrieve the hash
of a given file from IMA if it's present in the iint cache.

It's true that the existence of the hash means that it's also in the
audit logs or in /sys/kernel/security/ima/ascii_runtime_measurements,
but it can be difficult to pull that information out for every
subsequent exec. This is especially true if a given host has been up
for a long time and the file was first measured a long time ago.

It should be kept in mind that this function gives access to cached
entries which can be removed, for instance on security_inode_free().

This is based on Peter Moody's patch:
 https://sourceforge.net/p/linux-ima/mailman/message/33036180/

[1] https://lkml.org/lkml/2019/9/10/393Signed-off-by: Florent Revest <revest@google.com>
Reviewed-by: KP Singh <kpsingh@chromium.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

When reading ima_policy from securityfs, there is a missing
space between output string of LSM rules and the remaining
rules.
Signed-off-by: Clay Chang <clayc@hpe.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

As a result of the asymmetric public keys subtype Kconfig option being
defined as tristate, with the existing IMA Makefile, ima_asymmetric_keys.c
could be built as a kernel module.  To prevent this from happening, this
patch defines and uses an intermediate Kconfig boolean option named
IMA_MEASURE_ASYMMETRIC_KEYS.
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Suggested-by: James.Bottomley <James.Bottomley@HansenPartnership.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reported-by: kbuild test robot <lkp@intel.com> # ima_asymmetric_keys.c
is built as a kernel module.
Fixes: 88e70da1 ("IMA: Define an IMA hook to measure keys")
Fixes: cb1aa382 ("KEYS: Call the IMA hook to measure keys")
[zohar@linux.ibm.com: updated patch description]
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

From "KEYS: Measure keys when they are created or updated" cover letter:

Keys created or updated in the system are currently not measured.
Therefore an attestation service, for instance, would not be able to
attest whether or not the trusted keys keyring(s), for instance, contain
only known good (trusted) keys.

IMA measures system files, command line arguments passed to kexec,
boot aggregate, etc. It can be used to measure keys as well.
But there is no mechanism available in the kernel for IMA to
know when a key is created or updated.

This change aims to address measuring keys created or updated
in the system.

To achieve the above the following changes have been made:

 - Added a new IMA hook namely, ima_post_key_create_or_update, which
   measures the key. This IMA hook is called from key_create_or_update
   function. The key measurement can be controlled through IMA policy.

   A new IMA policy function KEY_CHECK has been added to measure keys.
   "keyrings=" option can be specified for KEY_CHECK to limit
   measuring the keys loaded onto the specified keyrings only.

   uid can be specified to further restrict key measurement for keys
   created by specific user.

   # measure keys loaded onto any keyring
   measure func=KEY_CHECK

   # measure keys loaded onto the IMA keyring only for root user
   measure func=KEY_CHECK uid=0 keyring=".ima"

   # measure keys on the BUILTIN and IMA keyrings into a different PCR
   measure func=KEY_CHECK keyring=".builtin_trusted_keys|.ima" pcr=11

Read "keyrings=" option, if specified in the IMA policy, and store in
the list of IMA rules when the configured IMA policy is read.

This patch defines a new policy token enum namely Opt_keyrings
and an option flag IMA_KEYRINGS for reading "keyrings=" option
from the IMA policy.

Updated ima_parse_rule() to parse "keyrings=" option in the policy.
Updated ima_policy_show() to display "keyrings=" option.

The following example illustrates how key measurement can be verified.

Sample "key" measurement rule in the IMA policy:

measure func=KEY_CHECK uid=0 keyrings=.ima|.evm template=ima-buf

Display "key" measurement in the IMA measurement list:

cat /sys/kernel/security/ima/ascii_runtime_measurements

10 faf3...e702 ima-buf sha256:27c915b8ddb9fae7214cf0a8a7043cc3eeeaa7539bcb136f8427067b5f6c3b7b .ima 308202863082...4aee

Verify "key" measurement data for a key added to ".ima" keyring:

cat /sys/kernel/security/integrity/ima/ascii_runtime_measurements | grep -m 1 "\.ima" | cut -d' ' -f 6 | xxd -r -p |tee ima-cert.der | sha256sum | cut -d' ' -f 1

The output of the above command should match the template hash
of the first "key" measurement entry in the IMA measurement list for
the key added to ".ima" keyring.

The file namely "ima-cert.der" generated by the above command
should be a valid x509 certificate (in DER format) and should match
the one that was used to import the key to the ".ima" keyring.
The certificate file can be verified using openssl tool.
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

Limit measuring keys to those keys being loaded onto a given set of
keyrings only and when the user id (uid) matches if uid is specified
in the policy.

This patch defines a new IMA policy option namely "keyrings=" that
can be used to specify a set of keyrings. If this option is specified
in the policy for "measure func=KEY_CHECK" then only the keys
loaded onto a keyring given in the "keyrings=" option are measured.

If uid is specified in the policy then the key is measured only if
the current user id matches the one specified in the policy.

Added a new parameter namely "keyring" (name of the keyring) to
process_buffer_measurement(). The keyring name is passed to
ima_get_action() to determine the required action.
ima_match_rules() is updated to check keyring in the policy, if
specified, for KEY_CHECK function.
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

Call the IMA hook from key_create_or_update() function to measure
the payload when a new key is created or an existing key is updated.

This patch adds the call to the IMA hook from key_create_or_update()
function to measure the key on key create or update.
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

Measure asymmetric keys used for verifying file signatures,
certificates, etc.

This patch defines a new IMA hook namely ima_post_key_create_or_update()
to measure the payload used to create a new asymmetric key or
update an existing asymmetric key.

Asymmetric key structure is defined only when
CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE is defined. Since the IMA hook
measures asymmetric keys, the IMA hook is defined in a new file namely
ima_asymmetric_keys.c which is built only if
CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE is defined.
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

Measure keys loaded onto any keyring.

This patch defines a new IMA policy func namely KEY_CHECK to
measure keys. Updated ima_match_rules() to check for KEY_CHECK
and ima_parse_rule() to handle KEY_CHECK.
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

process_buffer_measurement() may be called prior to IMA being
initialized (for instance, when the IMA hook is called when
a key is added to the .builtin_trusted_keys keyring), which
would result in a kernel panic.

This patch adds the check in process_buffer_measurement()
to return immediately if IMA is not initialized yet.
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

The integrity_kernel_read() call in ima_calc_file_hash_tfm() can return
a value of 0 before all bytes of the file are read. A value of 0 would
normally indicate an EOF. This has been observed if a user process is
causing a file appraisal and is terminated with a SIGTERM signal. The
most common occurrence of seeing the problem is if a shutdown or systemd
reload is initiated while files are being appraised.

The problem is similar to commit <f5e10401> (ima: always return
negative code for error) that fixed the problem in
ima_calc_file_hash_atfm().
Suggested-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Patrick Callaghan <patrickc@linux.ibm.com>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

Pull networking fixes from David Miller:

 1) More jumbo frame fixes in r8169, from Heiner Kallweit.

 2) Fix bpf build in minimal configuration, from Alexei Starovoitov.

 3) Use after free in slcan driver, from Jouni Hogander.

 4) Flower classifier port ranges don't work properly in the HW offload
    case, from Yoshiki Komachi.

 5) Use after free in hns3_nic_maybe_stop_tx(), from Yunsheng Lin.

 6) Out of bounds access in mqprio_dump(), from Vladyslav Tarasiuk.

 7) Fix flow dissection in dsa TX path, from Alexander Lobakin.

 8) Stale syncookie timestampe fixes from Guillaume Nault.

[ Did an evil merge to silence a warning introduced by this pull - Linus ]

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (84 commits)
  r8169: fix rtl_hw_jumbo_disable for RTL8168evl
  net_sched: validate TCA_KIND attribute in tc_chain_tmplt_add()
  r8169: add missing RX enabling for WoL on RTL8125
  vhost/vsock: accept only packets with the right dst_cid
  net: phy: dp83867: fix hfs boot in rgmii mode
  net: ethernet: ti: cpsw: fix extra rx interrupt
  inet: protect against too small mtu values.
  gre: refetch erspan header from skb->data after pskb_may_pull()
  pppoe: remove redundant BUG_ON() check in pppoe_pernet
  tcp: Protect accesses to .ts_recent_stamp with {READ,WRITE}_ONCE()
  tcp: tighten acceptance of ACKs not matching a child socket
  tcp: fix rejected syncookies due to stale timestamps
  lpc_eth: kernel BUG on remove
  tcp: md5: fix potential overestimation of TCP option space
  net: sched: allow indirect blocks to bind to clsact in TC
  net: core: rename indirect block ingress cb function
  net-sysfs: Call dev_hold always in netdev_queue_add_kobject
  net: dsa: fix flow dissection on Tx path
  net/tls: Fix return values to avoid ENOTSUPP
  net: avoid an indirect call in ____sys_recvmsg()
  ...

Pull more SCSI updates from James Bottomley:
 "Eleven patches, all in drivers (no core changes) that are either minor
  cleanups or small fixes.

  They were late arriving, but still safe for -rc1"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: MAINTAINERS: Add the linux-scsi mailing list to the ISCSI entry
  scsi: megaraid_sas: Make poll_aen_lock static
  scsi: sd_zbc: Improve report zones error printout
  scsi: qla2xxx: Fix qla2x00_request_irqs() for MSI
  scsi: qla2xxx: unregister ports after GPN_FT failure
  scsi: qla2xxx: fix rports not being mark as lost in sync fabric scan
  scsi: pm80xx: Remove unused include of linux/version.h
  scsi: pm80xx: fix logic to break out of loop when register value is 2 or 3
  scsi: scsi_transport_sas: Fix memory leak when removing devices
  scsi: lpfc: size cpu map by last cpu id set
  scsi: ibmvscsi_tgt: Remove unneeded variable rc

Pull cifs fixes from Steve French:
 "Nine cifs/smb3 fixes:

   - one fix for stable (oops during oplock break)

   - two timestamp fixes including important one for updating mtime at
     close to avoid stale metadata caching issue on dirty files (also
     improves perf by using SMB2_CLOSE_FLAG_POSTQUERY_ATTRIB over the
     wire)

   - two fixes for "modefromsid" mount option for file create (now
     allows mode bits to be set more atomically and accurately on create
     by adding "sd_context" on create when modefromsid specified on
     mount)

   - two fixes for multichannel found in testing this week against
     different servers

   - two small cleanup patches"

* tag '5.5-rc-smb3-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6:
  smb3: improve check for when we send the security descriptor context on create
  smb3: fix mode passed in on create for modetosid mount option
  cifs: fix possible uninitialized access and race on iface_list
  cifs: Fix lookup of SMB connections on multichannel
  smb3: query attributes on file close
  smb3: remove unused flag passed into close functions
  cifs: remove redundant assignment to pointer pneg_ctxt
  fs: cifs: Fix atime update check vs mtime
  CIFS: Fix NULL-pointer dereference in smb2_push_mandatory_locks

Pull misc vfs cleanups from Al Viro:
 "No common topic, just three cleanups".

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  make __d_alloc() static
  fs/namespace: add __user to open_tree and move_mount syscalls
  fs/fnctl: fix missing __user in fcntl_rw_hint()

Pull NTB update from Jon Mason:
 "Just a simple patch to add a new Hygon Device ID to the AMD NTB device
  driver"

* tag 'ntb-5.5' of git://github.com/jonmason/ntb:
  NTB: Add Hygon Device ID

Pull more input updates from Dmitry Torokhov:

 - fixups for Synaptics RMI4 driver

 - a quirk for Goodinx touchscreen on Teclast tablet

 - a new keycode definition for activating privacy screen feature found
   on a few "enterprise" laptops

 - updates to snvs_pwrkey driver

 - polling uinput device for writing (which is always allowed) now works

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: synaptics-rmi4 - don't increment rmiaddr for SMBus transfers
  Input: synaptics-rmi4 - re-enable IRQs in f34v7_do_reflash
  Input: goodix - add upside-down quirk for Teclast X89 tablet
  Input: add privacy screen toggle keycode
  Input: uinput - fix returning EPOLLOUT from uinput_poll
  Input: snvs_pwrkey - remove gratuitous NULL initializers
  Input: snvs_pwrkey - send key events for i.MX6 S, DL and Q

Pull iomap fixes from Darrick Wong:
 "Fix a race condition and a use-after-free error:

   - Fix a UAF when reporting writeback errors

   - Fix a race condition when handling page uptodate on fragmented file
     with blocksize < pagesize"

* tag 'iomap-5.5-merge-14' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  iomap: stop using ioend after it's been freed in iomap_finish_ioend()
  iomap: fix sub-page uptodate handling

Pull xfs fixes from Darrick Wong:
 "Fix a couple of resource management errors and a hang:

   - fix a crash in the log setup code when log mounting fails

   - fix a hang when allocating space on the realtime device

   - fix a block leak when freeing space on the realtime device"

* tag 'xfs-5.5-merge-17' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: fix mount failure crash on invalid iclog memory access
  xfs: don't check for AG deadlock for realtime files in bunmapi
  xfs: fix realtime file data space leak

Pull orangefs update from Mike Marshall:
 "orangefs: posix open permission checking...

  Orangefs has no open, and orangefs checks file permissions on each
  file access. Posix requires that file permissions be checked on open
  and nowhere else. Orangefs-through-the-kernel needs to seem posix
  compliant.

  The VFS opens files, even if the filesystem provides no method. We can
  see if a file was successfully opened for read and or for write by
  looking at file->f_mode.

  When writes are flowing from the page cache, file is no longer
  available. We can trust the VFS to have checked file->f_mode before
  writing to the page cache.

  The mode of a file might change between when it is opened and IO
  commences, or it might be created with an arbitrary mode.

  We'll make sure we don't hit EACCES during the IO stage by using
  UID 0"

[ This is "posixish", but not a great solution in the long run, since a
  proper secure network server shouldn't really trust the client like this.
  But proper and secure POSIX behavior requires an open method and a
  resulting cookie for IO of some kind, or similar.    - Linus ]

* tag 'for-linus-5.5-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
  orangefs: posix open permission checking...

Pull nfsd updates from Bruce Fields:
 "This is a relatively quiet cycle for nfsd, mainly various bugfixes.

  Possibly most interesting is Trond's fixes for some callback races
  that were due to my incomplete understanding of rpc client shutdown.
  Unfortunately at the last minute I've started noticing a new
  intermittent failure to send callbacks. As the logic seems basically
  correct, I'm leaving Trond's patches in for now, and hope to find a
  fix in the next week so I don't have to revert those patches"

* tag 'nfsd-5.5' of git://linux-nfs.org/~bfields/linux: (24 commits)
  nfsd: depend on CRYPTO_MD5 for legacy client tracking
  NFSD fixing possible null pointer derefering in copy offload
  nfsd: check for EBUSY from vfs_rmdir/vfs_unink.
  nfsd: Ensure CLONE persists data and metadata changes to the target file
  SUNRPC: Fix backchannel latency metrics
  nfsd: restore NFSv3 ACL support
  nfsd: v4 support requires CRYPTO_SHA256
  nfsd: Fix cld_net->cn_tfm initialization
  lockd: remove __KERNEL__ ifdefs
  sunrpc: remove __KERNEL__ ifdefs
  race in exportfs_decode_fh()
  nfsd: Drop LIST_HEAD where the variable it declares is never used.
  nfsd: document callback_wq serialization of callback code
  nfsd: mark cb path down on unknown errors
  nfsd: Fix races between nfsd4_cb_release() and nfsd4_shutdown_callback()
  nfsd: minor 4.1 callback cleanup
  SUNRPC: Fix svcauth_gss_proxy_init()
  SUNRPC: Trace gssproxy upcall results
  sunrpc: fix crash when cache_head become valid before update
  nfsd: remove private bin2hex implementation
  ...

Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  Features:

   - NFSv4.2 now supports cross device offloaded copy (i.e. offloaded
     copy of a file from one source server to a different target
     server).

   - New RDMA tracepoints for debugging congestion control and Local
     Invalidate WRs.

  Bugfixes and cleanups

   - Drop the NFSv4.1 session slot if nfs4_delegreturn_prepare waits for
     layoutreturn

   - Handle bad/dead sessions correctly in nfs41_sequence_process()

   - Various bugfixes to the delegation return operation.

   - Various bugfixes pertaining to delegations that have been revoked.

   - Cleanups to the NFS timespec code to avoid unnecessary conversions
     between timespec and timespec64.

   - Fix unstable RDMA connections after a reconnect

   - Close race between waking an RDMA sender and posting a receive

   - Wake pending RDMA tasks if connection fails

   - Fix MR list corruption, and clean up MR usage

   - Fix another RPCSEC_GSS issue with MIC buffer space"

* tag 'nfs-for-5.5-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (79 commits)
  SUNRPC: Capture completion of all RPC tasks
  SUNRPC: Fix another issue with MIC buffer space
  NFS4: Trace lock reclaims
  NFS4: Trace state recovery operation
  NFSv4.2 fix memory leak in nfs42_ssc_open
  NFSv4.2 fix kfree in __nfs42_copy_file_range
  NFS: remove duplicated include from nfs4file.c
  NFSv4: Make _nfs42_proc_copy_notify() static
  NFS: Fallocate should use the nfs4_fattr_bitmap
  NFS: Return -ETXTBSY when attempting to write to a swapfile
  fs: nfs: sysfs: Remove NULL check before kfree
  NFS: remove unneeded semicolon
  NFSv4: add declaration of current_stateid
  NFSv4.x: Drop the slot if nfs4_delegreturn_prepare waits for layoutreturn
  NFSv4.x: Handle bad/dead sessions correctly in nfs41_sequence_process()
  nfsv4: Move NFSPROC4_CLNT_COPY_NOTIFY to end of list
  SUNRPC: Avoid RPC delays when exiting suspend
  NFS: Add a tracepoint in nfs_fh_to_dentry()
  NFSv4: Don't retry the GETATTR on old stateid in nfs4_delegreturn_done()
  NFSv4: Handle NFS4ERR_OLD_STATEID in delegreturn
  ...

We had cases in the previous patch where we were sending the security
descriptor context on SMB3 open (file create) in cases when we hadn't
mounted with with "modefromsid" mount option.

Add check for that mount flag before calling ad_sd_context in
open init.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>

Pull VFIO updates from Alex Williamson:

 - Remove hugepage checks for reserved pfns (Ben Luo)

 - Fix irq-bypass unregister ordering (Jiang Yi)

* tag 'vfio-v5.5-rc1' of git://github.com/awilliam/linux-vfio:
  vfio/pci: call irq_bypass_unregister_producer() before freeing irq
  vfio/type1: remove hugepage checks in is_invalid_reserved_pfn()

Pull more xen updates from Juergen Gross:

 - a patch to fix a build warning

 - a cleanup of no longer needed code in the Xen event handling

 - a small series for the Xen grant driver avoiding high order
   allocations and replacing an insane global limit by a per-call one

 - a small series fixing Xen frontend/backend module referencing

* tag 'for-linus-5.5b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen-blkback: allow module to be cleanly unloaded
  xen/xenbus: reference count registered modules
  xen/gntdev: switch from kcalloc() to kvcalloc()
  xen/gntdev: replace global limit of mapped pages by limit per call
  xen/gntdev: remove redundant non-zero check on ret
  xen/events: remove event handling recursion detection

Merge misc Kconfig updates from Andrew Morton:
 "A number of changes to Kconfig files under lib/ from Changbin Du and
  Krzysztof Kozlowski"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  lib/: fix Kconfig indentation
  kernel-hacking: move DEBUG_FS to 'Generic Kernel Debugging Instruments'
  kernel-hacking: move DEBUG_BUGVERBOSE to 'printk and dmesg options'
  kernel-hacking: create a submenu for scheduler debugging options
  kernel-hacking: move SCHED_STACK_END_CHECK after DEBUG_STACK_USAGE
  kernel-hacking: move Oops into 'Lockups and Hangs'
  kernel-hacking: move kernel testing and coverage options to same submenu
  kernel-hacking: group kernel data structures debugging together
  kernel-hacking: create submenu for arch special debugging options
  kernel-hacking: group sysrq/kgdb/ubsan into 'Generic Kernel Debugging Instruments'

In referenced fix we removed the RTL8168e-specific jumbo config for
RTL8168evl in rtl_hw_jumbo_enable(). We have to do the same in
rtl_hw_jumbo_disable().

v2: fix referenced commit id

Fixes: 14012c9f ("r8169: fix jumbo configuration for RTL8168evl")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

pipe_wait() may be simple, but since it relies on the pipe lock, it
means that we have to do the wakeup while holding the lock.  That's
unfortunate, because the very first thing the waked entity will want to
do is to get the pipe lock for itself.

So get rid of the pipe_wait() usage by simply releasing the pipe lock,
doing the wakeup (if required) and then using wait_event_interruptible()
to wait on the right condition instead.

wait_event_interruptible() handles races on its own by comparing the
wakeup condition before and after adding itself to the wait queue, so
you can use an optimistic unlocked condition for it.

Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Jiasen Lin <linjiasen@hygon.cn>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

This code is ancient, and goes back to when we only had a single page
for the pipe buffers.  The exact history is hidden in the mists of time
(ie "before git", and in fact predates the BK repository too).

At that long-ago point in time, it actually helped to try to merge big
back-and-forth pipe reads and writes, and not limit pipe reads to the
single pipe buffer in length just because that was all we had at a time.

However, since then we've expanded the pipe buffers to multiple pages,
and this logic really doesn't seem to make sense.  And a lot of it is
somewhat questionable (ie "hmm, the user asked for a non-blocking read,
but we see that there's a writer pending, so let's wait anyway to get
the extra data that the writer will have").

But more importantly, it makes the "go to sleep" logic much less
obvious, and considering the wakeup issues we've had, I want to make for
less of those kinds of things.

Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This is the read side version of the previous commit: it simplifies the
logic to only wake up waiting writers when necessary, and makes sure to
use a synchronous wakeup.  This time not so much for GNU make jobserver
reasons (that pipe never fills up), but simply to get the writer going
quickly again.

A bit less verbose commentary this time, if only because I assume that
the write side commentary isn't going to be ignored if you touch this
code.

Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The pipe rework ends up having been extra painful, partly becaused of
actual bugs with ordering and caching of the pipe state, but also
because of subtle performance issues.

In particular, the pipe rework caused the kernel build to inexplicably
slow down.

The reason turns out to be that the GNU make jobserver (which limits the
parallelism of the build) uses a pipe to implement a "token" system: a
parallel submake will read a character from the pipe to get the job
token before starting a new job, and will write a character back to the
pipe when it is done.  The overall job limit is thus easily controlled
by just writing the appropriate number of initial token characters into
the pipe.

But to work well, that really means that the old behavior of write
wakeups being synchronous (WF_SYNC) is very important - when the pipe
writer wakes up a reader, we want the reader to actually get scheduled
immediately.  Otherwise you lose the parallelism of the build.

The pipe rework lost that synchronous wakeup on write, and we had
clearly all forgotten the reasons and rules for it.

This rewrites the pipe write wakeup logic to do the required Wsync
wakeups, but also clarifies the logic and avoids extraneous wakeups.

It also ends up addign a number of comments about what oit does and why,
so that we hopefully don't end up forgetting about this next time we
change this code.

Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Use the new tcf_proto_check_kind() helper to make sure user
provided value is well formed.

BUG: KMSAN: uninit-value in string_nocheck lib/vsprintf.c:606 [inline]
BUG: KMSAN: uninit-value in string+0x4be/0x600 lib/vsprintf.c:668
CPU: 0 PID: 12358 Comm: syz-executor.1 Not tainted 5.4.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0x128/0x220 mm/kmsan/kmsan_report.c:108
 __msan_warning+0x64/0xc0 mm/kmsan/kmsan_instr.c:245
 string_nocheck lib/vsprintf.c:606 [inline]
 string+0x4be/0x600 lib/vsprintf.c:668
 vsnprintf+0x218f/0x3210 lib/vsprintf.c:2510
 __request_module+0x2b1/0x11c0 kernel/kmod.c:143
 tcf_proto_lookup_ops+0x171/0x700 net/sched/cls_api.c:139
 tc_chain_tmplt_add net/sched/cls_api.c:2730 [inline]
 tc_ctl_chain+0x1904/0x38a0 net/sched/cls_api.c:2850
 rtnetlink_rcv_msg+0x115a/0x1580 net/core/rtnetlink.c:5224
 netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5242
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0xf3e/0x1020 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x110f/0x1330 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg net/socket.c:657 [inline]
 ___sys_sendmsg+0x14ff/0x1590 net/socket.c:2311
 __sys_sendmsg net/socket.c:2356 [inline]
 __do_sys_sendmsg net/socket.c:2365 [inline]
 __se_sys_sendmsg+0x305/0x460 net/socket.c:2363
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2363
 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45a649
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f0790795c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a649
RDX: 0000000000000000 RSI: 0000000020000300 RDI: 0000000000000006
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f07907966d4
R13: 00000000004c8db5 R14: 00000000004df630 R15: 00000000ffffffff

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:149 [inline]
 kmsan_internal_poison_shadow+0x5c/0x110 mm/kmsan/kmsan.c:132
 kmsan_slab_alloc+0x97/0x100 mm/kmsan/kmsan_hooks.c:86
 slab_alloc_node mm/slub.c:2773 [inline]
 __kmalloc_node_track_caller+0xe27/0x11a0 mm/slub.c:4381
 __kmalloc_reserve net/core/skbuff.c:141 [inline]
 __alloc_skb+0x306/0xa10 net/core/skbuff.c:209
 alloc_skb include/linux/skbuff.h:1049 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1174 [inline]
 netlink_sendmsg+0x783/0x1330 net/netlink/af_netlink.c:1892
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg net/socket.c:657 [inline]
 ___sys_sendmsg+0x14ff/0x1590 net/socket.c:2311
 __sys_sendmsg net/socket.c:2356 [inline]
 __do_sys_sendmsg net/socket.c:2365 [inline]
 __se_sys_sendmsg+0x305/0x460 net/socket.c:2363
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2363
 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: 6f96c3c6 ("net_sched: fix backward compatibility for TCA_KIND")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>

RTL8125 also requires to enable RX for WoL.

v2: add missing Fixes tag

Fixes: f1bce4ad ("r8169: add support for RTL8125")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When we receive a new packet from the guest, we check if the
src_cid is correct, but we forgot to check the dst_cid.

The host should accept only packets where dst_cid is
equal to the host CID.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>