Commit graph

68773 commits

Author SHA1 Message Date
David Howells
906357f77a x86/mmiotrace: Lock down the testmmiotrace module
The testmmiotrace module shouldn't be permitted when the kernel is locked
down as it can be used to arbitrarily read and write MMIO space. This is
a runtime check rather than buildtime in order to allow configurations
where the same kernel may be run in both locked down or permissive modes
depending on local policy.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Howells <dhowells@redhat.com
Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: Thomas Gleixner <tglx@linutronix.de>
cc: Steven Rostedt <rostedt@goodmis.org>
cc: Ingo Molnar <mingo@kernel.org>
cc: "H. Peter Anvin" <hpa@zytor.com>
cc: x86@kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:16 -07:00
David Howells
20657f66ef lockdown: Lock down module params that specify hardware parameters (eg. ioport)
Provided an annotation for module parameters that specify hardware
parameters (such as io ports, iomem addresses, irqs, dma channels, fixed
dma buffers and other types).

Suggested-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Jessica Yu <jeyu@kernel.org>
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:16 -07:00
David Howells
794edf30ee lockdown: Lock down TIOCSSERIAL
Lock down TIOCSSERIAL as that can be used to change the ioport and irq
settings on a serial port.  This only appears to be an issue for the serial
drivers that use the core serial code.  All other drivers seem to either
ignore attempts to change port/irq or give an error.

Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-serial@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:16 -07:00
David Howells
3f19cad3fa lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down
Prohibit replacement of the PCMCIA Card Information Structure when the
kernel is locked down.

Suggested-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:16 -07:00
Josh Boyer
41fa1ee9c6 acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
This option allows userspace to pass the RSDP address to the kernel, which
makes it possible for a user to modify the workings of hardware. Reject
the option when the kernel is locked down. This requires some reworking
of the existing RSDP command line logic, since the early boot code also
makes use of a command-line passed RSDP when locating the SRAT table
before the lockdown code has been initialised. This is achieved by
separating the command line RSDP path in the early boot code from the
generic RSDP path, and then copying the command line RSDP into boot
params in the kernel proper if lockdown is not enabled. If lockdown is
enabled and an RSDP is provided on the command line, this will only be
used when parsing SRAT (which shouldn't permit kernel code execution)
and will be ignored in the rest of the kernel.

(Modified by Matthew Garrett in order to handle the early boot RSDP
environment)

Signed-off-by: Josh Boyer <jwboyer@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: Dave Young <dyoung@redhat.com>
cc: linux-acpi@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:16 -07:00
Matthew Garrett
f474e1486b ACPI: Limit access to custom_method when the kernel is locked down
custom_method effectively allows arbitrary access to system memory, making
it possible for an attacker to circumvent restrictions on module loading.
Disable it if the kernel is locked down.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: linux-acpi@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:16 -07:00
Matthew Garrett
95f5e95f41 x86/msr: Restrict MSR access when the kernel is locked down
Writing to MSRs should not be allowed if the kernel is locked down, since
it could lead to execution of arbitrary code in kernel mode.  Based on a
patch by Kees Cook.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
cc: x86@kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:16 -07:00
Matthew Garrett
96c4f67293 x86: Lock down IO port access when the kernel is locked down
IO port access would permit users to gain access to PCI configuration
registers, which in turn (on a lot of hardware) give access to MMIO
register space. This would potentially permit root to trigger arbitrary
DMA, so lock it down by default.

This also implicitly locks down the KDADDIO, KDDELIO, KDENABIO and
KDDISABIO console ioctls.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: x86@kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:16 -07:00
Matthew Garrett
eb627e1772 PCI: Lock down BAR access when the kernel is locked down
Any hardware that can potentially generate DMA has to be locked down in
order to avoid it being possible for an attacker to modify kernel code,
allowing them to circumvent disabled module loading or module signing.
Default to paranoid - in future we can potentially relax this for
sufficiently IOMMU-isolated devices.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: linux-pci@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:15 -07:00
Josh Boyer
38bd94b8a1 hibernate: Disable when the kernel is locked down
There is currently no way to verify the resume image when returning
from hibernate.  This might compromise the signed modules trust model,
so until we can work with signed hibernate images we disable it when the
kernel is locked down.

Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: rjw@rjwysocki.net
Cc: pavel@ucw.cz
cc: linux-pm@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:15 -07:00
Jiri Bohac
99d5cadfde kexec_file: split KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE
This is a preparatory patch for kexec_file_load() lockdown.  A locked down
kernel needs to prevent unsigned kernel images from being loaded with
kexec_file_load().  Currently, the only way to force the signature
verification is compiling with KEXEC_VERIFY_SIG.  This prevents loading
usigned images even when the kernel is not locked down at runtime.

This patch splits KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE.
Analogous to the MODULE_SIG and MODULE_SIG_FORCE for modules, KEXEC_SIG
turns on the signature verification but allows unsigned images to be
loaded.  KEXEC_SIG_FORCE disallows images without a valid signature.

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
cc: kexec@lists.infradead.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:15 -07:00
Matthew Garrett
7d31f4602f kexec_load: Disable at runtime if the kernel is locked down
The kexec_load() syscall permits the loading and execution of arbitrary
code in ring 0, which is something that lock-down is meant to prevent. It
makes sense to disable kexec_load() in this situation.

This does not affect kexec_file_load() syscall which can check for a
signature on the image to be booted.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Dave Young <dyoung@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: kexec@lists.infradead.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:15 -07:00
Matthew Garrett
9b9d8dda1e lockdown: Restrict /dev/{mem,kmem,port} when the kernel is locked down
Allowing users to read and write to core kernel memory makes it possible
for the kernel to be subverted, avoiding module loading restrictions, and
also to steal cryptographic information.

Disallow /dev/mem and /dev/kmem from being opened this when the kernel has
been locked down to prevent this.

Also disallow /dev/port from being opened to prevent raw ioport access and
thus DMA from being used to accomplish the same thing.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: x86@kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:15 -07:00
David Howells
49fcf732bd lockdown: Enforce module signatures if the kernel is locked down
If the kernel is locked down, require that all modules have valid
signatures that we can verify.

I have adjusted the errors generated:

 (1) If there's no signature (ENODATA) or we can't check it (ENOPKG,
     ENOKEY), then:

     (a) If signatures are enforced then EKEYREJECTED is returned.

     (b) If there's no signature or we can't check it, but the kernel is
	 locked down then EPERM is returned (this is then consistent with
	 other lockdown cases).

 (2) If the signature is unparseable (EBADMSG, EINVAL), the signature fails
     the check (EKEYREJECTED) or a system error occurs (eg. ENOMEM), we
     return the error we got.

Note that the X.509 code doesn't check for key expiry as the RTC might not
be valid or might not have been transferred to the kernel's clock yet.

 [Modified by Matthew Garrett to remove the IMA integration. This will
  be replaced with integration with the IMA architecture policy
  patchset.]

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <matthewgarrett@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Jessica Yu <jeyu@kernel.org>
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:15 -07:00
Matthew Garrett
000d388ed3 security: Add a static lockdown policy LSM
While existing LSMs can be extended to handle lockdown policy,
distributions generally want to be able to apply a straightforward
static policy. This patch adds a simple LSM that can be configured to
reject either integrity or all lockdown queries, and can be configured
at runtime (through securityfs), boot time (via a kernel parameter) or
build time (via a kconfig option). Based on initial code by David
Howells.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:15 -07:00
Matthew Garrett
9e47d31d6a security: Add a "locked down" LSM hook
Add a mechanism to allow LSMs to make a policy decision around whether
kernel functionality that would allow tampering with or examining the
runtime state of the kernel should be permitted.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:15 -07:00
Matthew Garrett
e6b1db98cf security: Support early LSMs
The lockdown module is intended to allow for kernels to be locked down
early in boot - sufficiently early that we don't have the ability to
kmalloc() yet. Add support for early initialisation of some LSMs, and
then add them to the list of names when we do full initialisation later.
Early LSMs are initialised in link order and cannot be overridden via
boot parameters, and cannot make use of kmalloc() (since the allocator
isn't initialised yet).

(Fixed by Stephen Rothwell to include a stub to fix builds when
!CONFIG_SECURITY)

Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:15 -07:00
Linus Torvalds
287c55ed7d Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull kernel thread signal handling fix from Eric Biederman:
 "I overlooked the fact that kernel threads are created with all signals
  set to SIG_IGN, and accidentally caused a regression in cifs and drbd
  when replacing force_sig with send_sig.

  This is my fix for that regression. I add a new function
  allow_kernel_signal which allows kernel threads to receive signals
  sent from the kernel, but continues to ignore all signals sent from
  userspace. This ensures the user space interface for cifs and drbd
  remain the same.

  These kernel threads depend on blocking networking calls which block
  until something is received or a signal is pending. Making receiving
  of signals somewhat necessary for these kernel threads.

  Perhaps someday we can cleanup those interfaces and remove
  allow_kernel_signal. If not allow_kernel_signal is pretty trivial and
  clearly documents what is going on so I don't think we will mind
  carrying it"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  signal: Allow cifs and drbd to receive their terminating signals
2019-08-19 16:17:59 -07:00
David S. Miller
e15dbcdeb9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

1) Remove IP MASQUERADING record in MAINTAINERS file,
   from Denis Efremov.

2) Counter arguments are swapped in ebtables, from
   Todd Seidelmann.

3) Missing netlink attribute validation in flow_offload
   extension.

4) Incorrect alignment in xt_nfacct that breaks 32-bits
   userspace / 64-bits kernels, from Juliana Rodrigueiro.

5) Missing include guard in nf_conntrack_h323_types.h,
   from Masahiro Yamada.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-19 13:16:07 -07:00
David S. Miller
446bf64b61 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Merge conflict of mlx5 resolved using instructions in merge
commit 9566e650bf.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-19 11:54:03 -07:00
Linus Torvalds
06821504fd Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

  1) Fix jmp to 1st instruction in x64 JIT, from Alexei Starovoitov.

  2) Severl kTLS fixes in mlx5 driver, from Tariq Toukan.

  3) Fix severe performance regression due to lack of SKB coalescing of
     fragments during local delivery, from Guillaume Nault.

  4) Error path memory leak in sch_taprio, from Ivan Khoronzhuk.

  5) Fix batched events in skbedit packet action, from Roman Mashak.

  6) Propagate VLAN TX offload to hw_enc_features in bond and team
     drivers, from Yue Haibing.

  7) RXRPC local endpoint refcounting fix and read after free in
     rxrpc_queue_local(), from David Howells.

  8) Fix endian bug in ibmveth multicast list handling, from Thomas
     Falcon.

  9) Oops, make nlmsg_parse() wrap around the correct function,
     __nlmsg_parse not __nla_parse(). Fix from David Ahern.

 10) Memleak in sctp_scend_reset_streams(), fro Zheng Bin.

 11) Fix memory leak in cxgb4, from Wenwen Wang.

 12) Yet another race in AF_PACKET, from Eric Dumazet.

 13) Fix false detection of retransmit failures in tipc, from Tuong
     Lien.

 14) Use after free in ravb_tstamp_skb, from Tho Vu.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (101 commits)
  ravb: Fix use-after-free ravb_tstamp_skb
  netfilter: nf_tables: map basechain priority to hardware priority
  net: sched: use major priority number as hardware priority
  wimax/i2400m: fix a memory leak bug
  net: cavium: fix driver name
  ibmvnic: Unmap DMA address of TX descriptor buffers after use
  bnxt_en: Fix to include flow direction in L2 key
  bnxt_en: Use correct src_fid to determine direction of the flow
  bnxt_en: Suppress HWRM errors for HWRM_NVM_GET_VARIABLE command
  bnxt_en: Fix handling FRAG_ERR when NVM_INSTALL_UPDATE cmd fails
  bnxt_en: Improve RX doorbell sequence.
  bnxt_en: Fix VNIC clearing logic for 57500 chips.
  net: kalmia: fix memory leaks
  cx82310_eth: fix a memory leak bug
  bnx2x: Fix VF's VLAN reconfiguration in reload.
  Bluetooth: Add debug setting for changing minimum encryption key size
  tipc: fix false detection of retransmit failures
  lan78xx: Fix memory leaks
  MAINTAINERS: r8169: Update path to the driver
  MAINTAINERS: PHY LIBRARY: Update files in the record
  ...
2019-08-19 10:00:01 -07:00
David Howells
555df336c7 keys: Fix description size
The maximum key description size is 4095.  Commit f771fde820 ("keys:
Simplify key description management") inadvertantly reduced that to 255
and made sizes between 256 and 4095 work weirdly, and any size whereby
size & 255 == 0 would cause an assertion in __key_link_begin() at the
following line:

	BUG_ON(index_key->desc_len == 0);

This can be fixed by simply increasing the size of desc_len in struct
keyring_index_key to a u16.

Note the argument length test in keyutils only checked empty
descriptions and descriptions with a size around the limit (ie.  4095)
and not for all the values in between, so it missed this.  This has been
addressed and

	https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/keyutils.git/commit/?id=066bf56807c26cd3045a25f355b34c1d8a20a5aa

now exhaustively tests all possible lengths of type, description and
payload and then some.

The assertion failure looks something like:

 kernel BUG at security/keys/keyring.c:1245!
 ...
 RIP: 0010:__key_link_begin+0x88/0xa0
 ...
 Call Trace:
  key_create_or_update+0x211/0x4b0
  __x64_sys_add_key+0x101/0x200
  do_syscall_64+0x5b/0x1e0
  entry_SYSCALL_64_after_hwframe+0x44/0xa9

It can be triggered by:

	keyctl add user "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa" a @s

Fixes: f771fde820 ("keys: Simplify key description management")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-08-19 09:43:57 -07:00
Rasmus Villemoes
4333fb96ca media: lib/sort.c: implement sort() variant taking context argument
Our list_sort() utility has always supported a context argument that
is passed through to the comparison routine. Now there's a use case
for the similar thing for sort().

This implements sort_r by simply extending the existing sort function
in the obvious way. To avoid code duplication, we want to implement
sort() in terms of sort_r(). The naive way to do that is

static int cmp_wrapper(const void *a, const void *b, const void *ctx)
{
  int (*real_cmp)(const void*, const void*) = ctx;
  return real_cmp(a, b);
}

sort(..., cmp) { sort_r(..., cmp_wrapper, cmp) }

but this would do two indirect calls for each comparison. Instead, do
as is done for the default swap functions - that only adds a cost of a
single easily predicted branch to each comparison call.

Aside from introducing support for the context argument, this also
serves as preparation for patches that will eliminate the indirect
comparison calls in common cases.

Requested-by: Boris Brezillon <boris.brezillon@collabora.com>

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-08-19 13:14:53 -03:00
Trond Myklebust
b72679ee89 notify: export symbols for use by the knfsd file cache
The knfsd file cache will need to detect when files are unlinked, so that
it can close the associated cached files. Export a minimal set of notifier
functions to allow it to do so.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-08-19 11:00:39 -04:00
Jeff Layton
18f6622ebb locks: create a new notifier chain for lease attempts
With the new file caching infrastructure in nfsd, we can end up holding
files open for an indefinite period of time, even when they are still
idle. This may prevent the kernel from handing out leases on the file,
which is something we don't want to block.

Fix this by running a SRCU notifier call chain whenever on any
lease attempt. nfsd can then purge the cache for that inode before
returning.

Since SRCU is only conditionally compiled in, we must only define the
new chain if it's enabled, and users of the chain must ensure that
SRCU is enabled.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-08-19 11:00:39 -04:00
Jeff Layton
f69d6d8eef sunrpc: add a new cache_detail operation for when a cache is flushed
When the exports table is changed, exportfs will usually write a new
time to the "flush" file in the nfsd.export cache procfile. This tells
the kernel to flush any entries that are older than that value.

This gives us a mechanism to tell whether an unexport might have
occurred. Add a new ->flush cache_detail operation that is called after
flushing the cache whenever someone writes to a "flush" file.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-08-19 11:00:39 -04:00
Chuck Lever
4866073e6d svcrdma: Use llist for managing cache of recv_ctxts
Use a wait-free mechanism for managing the svc_rdma_recv_ctxts free
list. Subsequently, sc_recv_lock can be eliminated.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-08-19 10:59:28 -04:00
Chuck Lever
d6dfe43ec6 svcrdma: Remove svc_rdma_wq
Clean up: the system workqueue will work just as well.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-08-19 10:59:28 -04:00
Junxiao Bi
988721db93 block: remove struct request_queue queue_head
The dispatch list is not used any more, as the legacy block IO stack
has been removed.

Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-08-19 08:55:10 -06:00
Thomas Gleixner
b6a32bbd87 genirq: Force interrupt threading on RT
Switch force_irqthreads from a boot time modifiable variable to a compile
time constant when CONFIG_PREEMPT_RT is enabled.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190816160923.12855-1-bigeasy@linutronix.de
2019-08-19 15:45:48 +02:00
Masahiro Yamada
38a429c898 netfilter: add include guard to nf_conntrack_h323_types.h
Add a header include guard just in case.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-08-19 13:59:57 +02:00
Eric W. Biederman
33da8e7c81 signal: Allow cifs and drbd to receive their terminating signals
My recent to change to only use force_sig for a synchronous events
wound up breaking signal reception cifs and drbd.  I had overlooked
the fact that by default kthreads start out with all signals set to
SIG_IGN.  So a change I thought was safe turned out to have made it
impossible for those kernel thread to catch their signals.

Reverting the work on force_sig is a bad idea because what the code
was doing was very much a misuse of force_sig.  As the way force_sig
ultimately allowed the signal to happen was to change the signal
handler to SIG_DFL.  Which after the first signal will allow userspace
to send signals to these kernel threads.  At least for
wake_ack_receiver in drbd that does not appear actively wrong.

So correct this problem by adding allow_kernel_signal that will allow
signals whose siginfo reports they were sent by the kernel through,
but will not allow userspace generated signals, and update cifs and
drbd to call allow_kernel_signal in an appropriate place so that their
thread can receive this signal.

Fixing things this way ensures that userspace won't be able to send
signals and cause problems, that it is clear which signals the
threads are expecting to receive, and it guarantees that nothing
else in the system will be affected.

This change was partly inspired by similar cifs and drbd patches that
added allow_signal.

Reported-by: ronnie sahlberg <ronniesahlberg@gmail.com>
Reported-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Tested-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Cc: Steve French <smfrench@gmail.com>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Fixes: 247bc9470b ("cifs: fix rmmod regression in cifs.ko caused by force_sig changes")
Fixes: 72abe3bcf0 ("signal/cifs: Fix cifs_put_tcp_session to call send_sig instead of force_sig")
Fixes: fee109901f ("signal/drbd: Use send_sig not force_sig")
Fixes: 3cf5d076fb ("signal: Remove task parameter from force_sig")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-08-19 06:34:13 -05:00
Greg Kroah-Hartman
7ffc95e90e Merge 5.3-rc5 into usb-next
We need the usb fixes in here as well for other patches to build on.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-19 07:15:42 +02:00
Greg Kroah-Hartman
c6d6832ce3 Merge 5.3-rc5 into staging-next
We need the staging fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-19 07:13:42 +02:00
Greg Kroah-Hartman
e70c971d7d Merge 5.3-rc5 into char-misc-next
We need the char/misc fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-19 07:11:53 +02:00
Linus Torvalds
359334caf7 USB fixes for 5.3-rc5
Here are number of small USB fixes for 5.3-rc5.
 
 Syzbot has been on a tear recently now that it has some good USB
 debugging hooks integrated, so there's a number of fixes in here found
 by those tools for some _very_ old bugs.  Also a handful of gadget
 driver fixes for reported issues, some hopefully-final dma fixes for
 host controller drivers, and some new USB serial gadget driver ids.
 
 All of these have been in linux-next this week with no reported issues
 (the usb-serial ones were in linux-next in its own branch, but merged
 into mine on Friday.)
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-5.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
 "Here are number of small USB fixes for 5.3-rc5.

  Syzbot has been on a tear recently now that it has some good USB
  debugging hooks integrated, so there's a number of fixes in here found
  by those tools for some _very_ old bugs. Also a handful of gadget
  driver fixes for reported issues, some hopefully-final dma fixes for
  host controller drivers, and some new USB serial gadget driver ids.

  All of these have been in linux-next this week with no reported issues
  (the usb-serial ones were in linux-next in its own branch, but merged
  into mine on Friday)"

* tag 'usb-5.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: add a hcd_uses_dma helper
  usb: don't create dma pools for HCDs with a localmem_pool
  usb: chipidea: imx: fix EPROBE_DEFER support during driver probe
  usb: host: fotg2: restart hcd after port reset
  USB: CDC: fix sanity checks in CDC union parser
  usb: cdc-acm: make sure a refcount is taken early enough
  USB: serial: option: add the BroadMobi BM818 card
  USB: serial: option: Add Motorola modem UARTs
  USB: core: Fix races in character device registration and deregistraion
  usb: gadget: mass_storage: Fix races between fsg_disable and fsg_set_alt
  usb: gadget: composite: Clear "suspended" on reset/disconnect
  usb: gadget: udc: renesas_usb3: Fix sysfs interface of "role"
  USB: serial: option: add D-Link DWM-222 device ID
  USB: serial: option: Add support for ZTE MF871A
2019-08-18 09:11:29 -07:00
Linus Torvalds
8fde2832bd for-linus-2019-08-17
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Merge tag 'for-linus-2019-08-17' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "A collection of fixes that should go into this series. This contains:

   - Revert of the REQ_NOWAIT_INLINE and associated dio changes. There
     were still corner cases there, and even though I had a solution for
     it, it's too involved for this stage. (me)

   - Set of NVMe fixes (via Sagi)

   - io_uring fix for fixed buffers (Anthony)

   - io_uring defer issue fix (Jackie)

   - Regression fix for queue sync at exit time (zhengbin)

   - xen blk-back memory leak fix (Wenwen)"

* tag 'for-linus-2019-08-17' of git://git.kernel.dk/linux-block:
  io_uring: fix an issue when IOSQE_IO_LINK is inserted into defer list
  block: remove REQ_NOWAIT_INLINE
  io_uring: fix manual setup of iov_iter for fixed buffers
  xen/blkback: fix memory leaks
  blk-mq: move cancel of requeue_work to the front of blk_exit_queue
  nvme-pci: Fix async probe remove race
  nvme: fix controller removal race with scan work
  nvme-rdma: fix possible use-after-free in connect error flow
  nvme: fix a possible deadlock when passthru commands sent to a multipath device
  nvme-core: Fix extra device_put() call on error path
  nvmet-file: fix nvmet_file_flush() always returning an error
  nvmet-loop: Flush nvme_delete_wq when removing the port
  nvmet: Fix use-after-free bug when a port is removed
  nvme-multipath: revalidate nvme_ns_head gendisk in nvme_validate_ns
2019-08-17 19:39:54 -07:00
Stanislav Fomichev
b0e4701ce1 bpf: export bpf_map_inc_not_zero
Rename existing bpf_map_inc_not_zero to __bpf_map_inc_not_zero to
indicate that it's caller's responsibility to do proper locking.
Create and export bpf_map_inc_not_zero wrapper that properly
locks map_idr_lock. Will be used in the next commit to
hold a map while cloning a socket.

Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-08-17 23:18:54 +02:00
Magnus Karlsson
9116e5e2b1 xsk: replace ndo_xsk_async_xmit with ndo_xsk_wakeup
This commit replaces ndo_xsk_async_xmit with ndo_xsk_wakeup. This new
ndo provides the same functionality as before but with the addition of
a new flags field that is used to specifiy if Rx, Tx or both should be
woken up. The previous ndo only woke up Tx, as implied by the
name. The i40e and ixgbe drivers (which are all the supported ones)
are updated with this new interface.

This new ndo will be used by the new need_wakeup functionality of XDP
sockets that need to be able to wake up both Rx and Tx driver
processing.

Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-08-17 23:07:31 +02:00
Heiner Kallweit
4b9cb2a5ce net: phy: remove genphy_config_init
Now that all users have been removed we can remove genphy_config_init.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-17 12:34:50 -07:00
Chris Wilson
f2cb60e9a3 dma-fence: Store the timestamp in the same union as the cb_list
The timestamp and the cb_list are mutually exclusive, the cb_list can
only be added to prior to being signaled (and once signaled we drain),
while the timestamp is only valid upon being signaled. Both the
timestamp and the cb_list are only valid while the fence is alive, and
as soon as no references are held can be replaced by the rcu_head.

By reusing the union for the timestamp, we squeeze the base dma_fence
struct to 64 bytes on x86-64.

v2: Sort the union chronologically

Suggested-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Christian König <christian.koenig@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>.
Link: https://patchwork.freedesktop.org/patch/msgid/20190817153022.5749-1-chris@chris-wilson.co.uk
2019-08-17 18:46:33 +01:00
Chris Wilson
4fe3997a68 dma-fence: Shrink size of struct dma_fence
Rearrange the couple of 32-bit atomics hidden amongst the field of
pointers that unnecessarily caused the compiler to insert some padding,
shrinks the size of the base struct dma_fence from 80 to 72 bytes on
x86-64.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Christian König <christian.koenig@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190817144736.7826-3-chris@chris-wilson.co.uk
2019-08-17 18:02:49 +01:00
Christoph Hellwig
f7bc6e42bf drivers: remove the SGI SN2 IOC4 base support
The IOC4 is a multi-function chip seen on SGI SN2 and some SGI MIPS
systems.  This removes the base driver, which while not having an SN2
Kconfig dependency was only for sub-drivers that had one.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lkml.kernel.org/r/20190813072514.23299-15-hch@lst.de
Signed-off-by: Tony Luck <tony.luck@intel.com>
2019-08-16 11:33:57 -07:00
Stephen Boyd
0214f33c4e clk: Overwrite clk_hw::init with NULL during clk_register()
We don't want clk provider drivers to use the init structure after clk
registration time, but we leave a dangling reference to it by means of
clk_hw::init. Let's overwrite the member with NULL during clk_register()
so that this can't be used anymore after registration time.

Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Doug Anderson <dianders@chromium.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lkml.kernel.org/r/20190731193517.237136-10-sboyd@kernel.org
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
2019-08-16 10:27:29 -07:00
Linus Torvalds
2d63ba3e41 Power management fixes for 5.3-rc5
- Disable NVMe power optimization related to suspend-to-idle added
    recently on systems where PCIe ASPM is not able to put PCIe links
    into low-power states to prevent excess power from being drawn by
    the system while suspended (Rafael Wysocki).
 
  - Make the schedutil governor handle frequency limits changes
    properly in all cases (Viresh Kumar).
 
  - Prevent the cpufreq core from treating positive values returned
    by dev_pm_qos_update_request() as errors (Viresh Kumar).
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Merge tag 'pm-5.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These add a check to avoid recent suspend-to-idle power regression on
  systems with NVMe drives where the PCIe ASPM policy is "performance"
  (or when the kernel is built without ASPM support), fix an issue
  related to frequency limits in the schedutil cpufreq governor and fix
  a mistake related to the PM QoS usage in the cpufreq core introduced
  recently.

  Specifics:

   - Disable NVMe power optimization related to suspend-to-idle added
     recently on systems where PCIe ASPM is not able to put PCIe links
     into low-power states to prevent excess power from being drawn by
     the system while suspended (Rafael Wysocki).

   - Make the schedutil governor handle frequency limits changes
     properly in all cases (Viresh Kumar).

   - Prevent the cpufreq core from treating positive values returned by
     dev_pm_qos_update_request() as errors (Viresh Kumar)"

* tag 'pm-5.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  nvme-pci: Allow PCI bus-level PM to be used if ASPM is disabled
  PCI/ASPM: Add pcie_aspm_enabled()
  cpufreq: schedutil: Don't skip freq update when limits change
  cpufreq: dev_pm_qos_update_request() can return 1 on success
2019-08-16 09:13:16 -07:00
Jason Gunthorpe
2c7933f53f mm/mmu_notifiers: add a get/put scheme for the registration
Many places in the kernel have a flow where userspace will create some
object and that object will need to connect to the subsystem's
mmu_notifier subscription for the duration of its lifetime.

In this case the subsystem is usually tracking multiple mm_structs and it
is difficult to keep track of what struct mmu_notifier's have been
allocated for what mm's.

Since this has been open coded in a variety of exciting ways, provide core
functionality to do this safely.

This approach uses the struct mmu_notifier_ops * as a key to determine if
the subsystem has a notifier registered on the mm or not. If there is a
registration then the existing notifier struct is returned, otherwise the
ops->alloc_notifiers() is used to create a new per-subsystem notifier for
the mm.

The destroy side incorporates an async call_srcu based destruction which
will avoid bugs in the callers such as commit 6d7c3cde93 ("mm/hmm: fix
use after free with struct hmm in the mmu notifiers").

Since we are inside the mmu notifier core locking is fairly simple, the
allocation uses the same approach as for mmu_notifier_mm, the write side
of the mmap_sem makes everything deterministic and we only need to do
hlist_add_head_rcu() under the mm_take_all_locks(). The new users count
and the discoverability in the hlist is fully serialized by the
mmu_notifier_mm->lock.

Link: https://lore.kernel.org/r/20190806231548.25242-4-jgg@ziepe.ca
Co-developed-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Tested-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-08-16 12:02:52 -03:00
Logan Gunthorpe
7f73eac3a7 PCI/P2PDMA: Introduce pci_p2pdma_unmap_sg()
Add pci_p2pdma_unmap_sg() to the two places that call pci_p2pdma_map_sg().

This is a prep patch to introduce correct mappings for p2pdma transactions
that go through the root complex.

Link: https://lore.kernel.org/r/20190730163545.4915-10-logang@deltatee.com
Link: https://lore.kernel.org/r/20190812173048.9186-10-logang@deltatee.com
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16 08:41:26 -05:00
Logan Gunthorpe
2b9f4bb2a4 PCI/P2PDMA: Add attrs argument to pci_p2pdma_map_sg()
This is to match the dma_map_sg() API which this function will have to call
in an future patch.

Add a pci_p2pdma_map_sg_attrs() function and helper to call it with no
attributes just like the dma_map_sg() function.

Link: https://lore.kernel.org/r/20190730163545.4915-9-logang@deltatee.com
Link: https://lore.kernel.org/r/20190812173048.9186-9-logang@deltatee.com
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16 08:41:15 -05:00
Logan Gunthorpe
a6e6fe6549 PCI/P2PDMA: Introduce private pagemap structure
Move the PCI bus offset from the generic dev_pagemap structure to a
specific pci_p2pdma_pagemap structure.

This structure will grow in subsequent patches.

Link: https://lore.kernel.org/r/20190730163545.4915-2-logang@deltatee.com
Link: https://lore.kernel.org/r/20190812173048.9186-2-logang@deltatee.com
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2019-08-16 08:38:52 -05:00
Chris Wilson
b016cd6ed4 dma-buf: Restore seqlock around dma_resv updates
This reverts
67c97fb79a ("dma-buf: add reservation_object_fences helper")
dd7a7d1ff2 ("drm/i915: use new reservation_object_fences helper")
0e1d8083bd ("dma-buf: further relax reservation_object_add_shared_fence")
5d344f58da ("dma-buf: nuke reservation_object seq number")

The scenario that defeats simply grabbing a set of shared/exclusive
fences and using them blissfully under RCU is that any of those fences
may be reallocated by a SLAB_TYPESAFE_BY_RCU fence slab cache. In this
scenario, while keeping the rcu_read_lock we need to establish that no
fence was changed in the dma_resv after a read (or full) memory barrier.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190814182401.25009-1-chris@chris-wilson.co.uk
2019-08-16 12:40:58 +01:00