There is a race condition which results in a deadlock when rmdir and
mkdir execute concurrently:

$ ls /sys/fs/resctrl/c1/mon_groups/m1/
cpus  cpus_list  mon_data  tasks

Thread 1: rmdir /sys/fs/resctrl/c1
Thread 2: mkdir /sys/fs/resctrl/c1/mon_groups/m1

3 locks held by mkdir/48649:
 #0:  (sb_writers#17){.+.+}, at: [<ffffffffb4ca2aa0>] mnt_want_write+0x20/0x50
 #1:  (&type->i_mutex_dir_key#8/1){+.+.}, at: [<ffffffffb4c8c13b>] filename_create+0x7b/0x170
 #2:  (rdtgroup_mutex){+.+.}, at: [<ffffffffb4a4389d>] rdtgroup_kn_lock_live+0x3d/0x70

4 locks held by rmdir/48652:
 #0:  (sb_writers#17){.+.+}, at: [<ffffffffb4ca2aa0>] mnt_want_write+0x20/0x50
 #1:  (&type->i_mutex_dir_key#8/1){+.+.}, at: [<ffffffffb4c8c3cf>] do_rmdir+0x13f/0x1e0
 #2:  (&type->i_mutex_dir_key#8){++++}, at: [<ffffffffb4c86d5d>] vfs_rmdir+0x4d/0x120
 #3:  (rdtgroup_mutex){+.+.}, at: [<ffffffffb4a4389d>] rdtgroup_kn_lock_live+0x3d/0x70

Thread 1 is deleting control group "c1". Holding rdtgroup_mutex,
kernfs_remove() removes all kernfs nodes under directory "c1"
recursively, then waits for sub kernfs node "mon_groups" to drop active
reference.

Thread 2 is trying to create a subdirectory "m1" in the "mon_groups"
directory. The wrapper kernfs_iop_mkdir() takes an active reference to
the "mon_groups" directory but the code drops the active reference to
the parent directory "c1" instead.

As a result, Thread 1 is blocked on waiting for active reference to drop
and never release rdtgroup_mutex, while Thread 2 is also blocked on
trying to get rdtgroup_mutex.

Thread 1 (rdtgroup_rmdir)   Thread 2 (rdtgroup_mkdir)
(rmdir /sys/fs/resctrl/c1)  (mkdir /sys/fs/resctrl/c1/mon_groups/m1)
-------------------------   -------------------------
                            kernfs_iop_mkdir
                              /*
                               * kn: "m1", parent_kn: "mon_groups",
                               * prgrp_kn: parent_kn->parent: "c1",
                               *
                               * "mon_groups", parent_kn->active++: 1
                               */
                              kernfs_get_active(parent_kn)
kernfs_iop_rmdir
  /* "c1", kn->active++ */
  kernfs_get_active(kn)

  rdtgroup_kn_lock_live
    atomic_inc(&rdtgrp->waitcount)
    /* "c1", kn->active-- */
    kernfs_break_active_protection(kn)
    mutex_lock

  rdtgroup_rmdir_ctrl
    free_all_child_rdtgrp
      sentry->flags = RDT_DELETED

    rdtgroup_ctrl_remove
      rdtgrp->flags = RDT_DELETED
      kernfs_get(kn)
      kernfs_remove(rdtgrp->kn)
        __kernfs_remove
          /* "mon_groups", sub_kn */
          atomic_add(KN_DEACTIVATED_BIAS, &sub_kn->active)
          kernfs_drain(sub_kn)
            /*
             * sub_kn->active == KN_DEACTIVATED_BIAS + 1,
             * waiting on sub_kn->active to drop, but it
             * never drops in Thread 2 which is blocked
             * on getting rdtgroup_mutex.
             */
Thread 1 hangs here ---->
            wait_event(sub_kn->active == KN_DEACTIVATED_BIAS)
            ...
                              rdtgroup_mkdir
                                rdtgroup_mkdir_mon(parent_kn, prgrp_kn)
                                  mkdir_rdt_prepare(parent_kn, prgrp_kn)
                                    rdtgroup_kn_lock_live(prgrp_kn)
                                      atomic_inc(&rdtgrp->waitcount)
                                      /*
                                       * "c1", prgrp_kn->active--
                                       *
                                       * The active reference on "c1" is
                                       * dropped, but not matching the
                                       * actual active reference taken
                                       * on "mon_groups", thus causing
                                       * Thread 1 to wait forever while
                                       * holding rdtgroup_mutex.
                                       */
                                      kernfs_break_active_protection(
                                                               prgrp_kn)
                                      /*
                                       * Trying to get rdtgroup_mutex
                                       * which is held by Thread 1.
                                       */
Thread 2 hangs here ---->             mutex_lock
                                      ...

The problem is that the creation of a subdirectory in the "mon_groups"
directory incorrectly releases the active protection of its parent
directory instead of itself before it starts waiting for rdtgroup_mutex.
This is triggered by the rdtgroup_mkdir() flow calling
rdtgroup_kn_lock_live()/rdtgroup_kn_unlock() with kernfs node of the
parent control group ("c1") as argument. It should be called with kernfs
node "mon_groups" instead. What is currently missing is that the
kn->priv of "mon_groups" is NULL instead of pointing to the rdtgrp.

Fix it by pointing kn->priv to rdtgrp when "mon_groups" is created. Then
it could be passed to rdtgroup_kn_lock_live()/rdtgroup_kn_unlock()
instead. And then it operates on the same rdtgroup structure but handles
the active reference of kernfs node "mon_groups" to prevent deadlock.
The same changes are also made to the "mon_data" directories.

This results in some unused function parameters that will be cleaned up
in follow-up patch as the focus here is on the fix only in support of
backporting efforts.

Fixes: c7d9aac6 ("x86/intel_rdt/cqm: Add mkdir support for RDT monitoring")
Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1578500886-21771-4-git-send-email-xiaochen.shen@intel.com

There is a race condition in the following scenario which results in an
use-after-free issue when reading a monitoring file and deleting the
parent ctrl_mon group concurrently:

Thread 1 calls atomic_inc() to take refcount of rdtgrp and then calls
kernfs_break_active_protection() to drop the active reference of kernfs
node in rdtgroup_kn_lock_live().

In Thread 2, kernfs_remove() is a blocking routine. It waits on all sub
kernfs nodes to drop the active reference when removing all subtree
kernfs nodes recursively. Thread 2 could block on kernfs_remove() until
Thread 1 calls kernfs_break_active_protection(). Only after
kernfs_remove() completes the refcount of rdtgrp could be trusted.

Before Thread 1 calls atomic_inc() and kernfs_break_active_protection(),
Thread 2 could call kfree() when the refcount of rdtgrp (sentry) is 0
instead of 1 due to the race.

In Thread 1, in rdtgroup_kn_unlock(), referring to earlier rdtgrp memory
(rdtgrp->waitcount) which was already freed in Thread 2 results in
use-after-free issue.

Thread 1 (rdtgroup_mondata_show)  Thread 2 (rdtgroup_rmdir)
--------------------------------  -------------------------
rdtgroup_kn_lock_live
  /*
   * kn active protection until
   * kernfs_break_active_protection(kn)
   */
  rdtgrp = kernfs_to_rdtgroup(kn)
                                  rdtgroup_kn_lock_live
                                    atomic_inc(&rdtgrp->waitcount)
                                    mutex_lock
                                  rdtgroup_rmdir_ctrl
                                    free_all_child_rdtgrp
                                      /*
                                       * sentry->waitcount should be 1
                                       * but is 0 now due to the race.
                                       */
                                      kfree(sentry)*[1]
  /*
   * Only after kernfs_remove()
   * completes, the refcount of
   * rdtgrp could be trusted.
   */
  atomic_inc(&rdtgrp->waitcount)
  /* kn->active-- */
  kernfs_break_active_protection(kn)
                                    rdtgroup_ctrl_remove
                                      rdtgrp->flags = RDT_DELETED
                                      /*
                                       * Blocking routine, wait for
                                       * all sub kernfs nodes to drop
                                       * active reference in
                                       * kernfs_break_active_protection.
                                       */
                                      kernfs_remove(rdtgrp->kn)
                                  rdtgroup_kn_unlock
                                    mutex_unlock
                                    atomic_dec_and_test(
                                                &rdtgrp->waitcount)
                                    && (flags & RDT_DELETED)
                                      kernfs_unbreak_active_protection(kn)
                                      kfree(rdtgrp)
  mutex_lock
mon_event_read
rdtgroup_kn_unlock
  mutex_unlock
  /*
   * Use-after-free: refer to earlier rdtgrp
   * memory which was freed in [1].
   */
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
    /* kn->active++ */
    kernfs_unbreak_active_protection(kn)
    kfree(rdtgrp)

Fix it by moving free_all_child_rdtgrp() to after kernfs_remove() in
rdtgroup_rmdir_ctrl() to ensure it has the accurate refcount of rdtgrp.

Fixes: f3cbeaca ("x86/intel_rdt/cqm: Add rmdir support")
Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1578500886-21771-3-git-send-email-xiaochen.shen@intel.com

A resource group (rdtgrp) contains a reference count (rdtgrp->waitcount)
that indicates how many waiters expect this rdtgrp to exist. Waiters
could be waiting on rdtgroup_mutex or some work sitting on a task's
workqueue for when the task returns from kernel mode or exits.

The deletion of a rdtgrp is intended to have two phases:

  (1) while holding rdtgroup_mutex the necessary cleanup is done and
  rdtgrp->flags is set to RDT_DELETED,

  (2) after releasing the rdtgroup_mutex, the rdtgrp structure is freed
  only if there are no waiters and its flag is set to RDT_DELETED. Upon
  gaining access to rdtgroup_mutex or rdtgrp, a waiter is required to check
  for the RDT_DELETED flag.

When unmounting the resctrl file system or deleting ctrl_mon groups,
all of the subdirectories are removed and the data structure of rdtgrp
is forcibly freed without checking rdtgrp->waitcount. If at this point
there was a waiter on rdtgrp then a use-after-free issue occurs when the
waiter starts running and accesses the rdtgrp structure it was waiting
on.

See kfree() calls in [1], [2] and [3] in these two call paths in
following scenarios:
(1) rdt_kill_sb() -> rmdir_all_sub() -> free_all_child_rdtgrp()
(2) rdtgroup_rmdir() -> rdtgroup_rmdir_ctrl() -> free_all_child_rdtgrp()

There are several scenarios that result in use-after-free issue in
following:

Scenario 1:
-----------
In Thread 1, rdtgroup_tasks_write() adds a task_work callback
move_myself(). If move_myself() is scheduled to execute after Thread 2
rdt_kill_sb() is finished, referring to earlier rdtgrp memory
(rdtgrp->waitcount) which was already freed in Thread 2 results in
use-after-free issue.

Thread 1 (rdtgroup_tasks_write)        Thread 2 (rdt_kill_sb)
-------------------------------        ----------------------
rdtgroup_kn_lock_live
  atomic_inc(&rdtgrp->waitcount)
  mutex_lock
rdtgroup_move_task
  __rdtgroup_move_task
    /*
     * Take an extra refcount, so rdtgrp cannot be freed
     * before the call back move_myself has been invoked
     */
    atomic_inc(&rdtgrp->waitcount)
    /* Callback move_myself will be scheduled for later */
    task_work_add(move_myself)
rdtgroup_kn_unlock
  mutex_unlock
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
                                       mutex_lock
                                       rmdir_all_sub
                                         /*
                                          * sentry and rdtgrp are freed
                                          * without checking refcount
                                          */
                                         free_all_child_rdtgrp
                                           kfree(sentry)*[1]
                                         kfree(rdtgrp)*[2]
                                       mutex_unlock
/*
 * Callback is scheduled to execute
 * after rdt_kill_sb is finished
 */
move_myself
  /*
   * Use-after-free: refer to earlier rdtgrp
   * memory which was freed in [1] or [2].
   */
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
    kfree(rdtgrp)

Scenario 2:
-----------
In Thread 1, rdtgroup_tasks_write() adds a task_work callback
move_myself(). If move_myself() is scheduled to execute after Thread 2
rdtgroup_rmdir() is finished, referring to earlier rdtgrp memory
(rdtgrp->waitcount) which was already freed in Thread 2 results in
use-after-free issue.

Thread 1 (rdtgroup_tasks_write)        Thread 2 (rdtgroup_rmdir)
-------------------------------        -------------------------
rdtgroup_kn_lock_live
  atomic_inc(&rdtgrp->waitcount)
  mutex_lock
rdtgroup_move_task
  __rdtgroup_move_task
    /*
     * Take an extra refcount, so rdtgrp cannot be freed
     * before the call back move_myself has been invoked
     */
    atomic_inc(&rdtgrp->waitcount)
    /* Callback move_myself will be scheduled for later */
    task_work_add(move_myself)
rdtgroup_kn_unlock
  mutex_unlock
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
                                       rdtgroup_kn_lock_live
                                         atomic_inc(&rdtgrp->waitcount)
                                         mutex_lock
                                       rdtgroup_rmdir_ctrl
                                         free_all_child_rdtgrp
                                           /*
                                            * sentry is freed without
                                            * checking refcount
                                            */
                                           kfree(sentry)*[3]
                                         rdtgroup_ctrl_remove
                                           rdtgrp->flags = RDT_DELETED
                                       rdtgroup_kn_unlock
                                         mutex_unlock
                                         atomic_dec_and_test(
                                                     &rdtgrp->waitcount)
                                         && (flags & RDT_DELETED)
                                           kfree(rdtgrp)
/*
 * Callback is scheduled to execute
 * after rdt_kill_sb is finished
 */
move_myself
  /*
   * Use-after-free: refer to earlier rdtgrp
   * memory which was freed in [3].
   */
  atomic_dec_and_test(&rdtgrp->waitcount)
  && (flags & RDT_DELETED)
    kfree(rdtgrp)

If CONFIG_DEBUG_SLAB=y, Slab corruption on kmalloc-2k can be observed
like following. Note that "0x6b" is POISON_FREE after kfree(). The
corrupted bits "0x6a", "0x64" at offset 0x424 correspond to
waitcount member of struct rdtgroup which was freed:

  Slab corruption (Not tainted): kmalloc-2k start=ffff9504c5b0d000, len=2048
  420: 6b 6b 6b 6b 6a 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkjkkkkkkkkkkk
  Single bit error detected. Probably bad RAM.
  Run memtest86+ or a similar memory test tool.
  Next obj: start=ffff9504c5b0d800, len=2048
  000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
  010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk

  Slab corruption (Not tainted): kmalloc-2k start=ffff9504c58ab800, len=2048
  420: 6b 6b 6b 6b 64 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkdkkkkkkkkkkk
  Prev obj: start=ffff9504c58ab000, len=2048
  000: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
  010: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk

Fix this by taking reference count (waitcount) of rdtgrp into account in
the two call paths that currently do not do so. Instead of always
freeing the resource group it will only be freed if there are no waiters
on it. If there are waiters, the resource group will have its flags set
to RDT_DELETED.

It will be left to the waiter to free the resource group when it starts
running and finding that it was the last waiter and the resource group
has been removed (rdtgrp->flags & RDT_DELETED) since. (1) rdt_kill_sb()
-> rmdir_all_sub() -> free_all_child_rdtgrp() (2) rdtgroup_rmdir() ->
rdtgroup_rmdir_ctrl() -> free_all_child_rdtgrp()

Fixes: f3cbeaca ("x86/intel_rdt/cqm: Add rmdir support")
Fixes: 60cf5e10 ("x86/intel_rdt: Add mkdir to resctrl file system")
Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1578500886-21771-2-git-send-email-xiaochen.shen@intel.com

Pull RISC-V fixes from Paul Walmsley:
 "Three fixes for RISC-V:

   - Don't free and reuse memory containing the code that CPUs parked at
     boot reside in.

   - Fix rv64 build problems for ubsan and some modules by adding
     logical and arithmetic shift helpers for 128-bit values. These are
     from libgcc and are similar to what's present for ARM64.

   - Fix vDSO builds to clean up their own temporary files"

* tag 'riscv/for-v5.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: Less inefficient gcc tishift helpers (and export their symbols)
  riscv: delete temporary files
  riscv: make sure the cores stay looping in .Lsecondary_park

Pull networking fixes from David Miller:

 1) Fix non-blocking connect() in x25, from Martin Schiller.

 2) Fix spurious decryption errors in kTLS, from Jakub Kicinski.

 3) Netfilter use-after-free in mtype_destroy(), from Cong Wang.

 4) Limit size of TSO packets properly in lan78xx driver, from Eric
    Dumazet.

 5) r8152 probe needs an endpoint sanity check, from Johan Hovold.

 6) Prevent looping in tcp_bpf_unhash() during sockmap/tls free, from
    John Fastabend.

 7) hns3 needs short frames padded on transmit, from Yunsheng Lin.

 8) Fix netfilter ICMP header corruption, from Eyal Birger.

 9) Fix soft lockup when low on memory in hns3, from Yonglong Liu.

10) Fix NTUPLE firmware command failures in bnxt_en, from Michael Chan.

11) Fix memory leak in act_ctinfo, from Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (91 commits)
  cxgb4: reject overlapped queues in TC-MQPRIO offload
  cxgb4: fix Tx multi channel port rate limit
  net: sched: act_ctinfo: fix memory leak
  bnxt_en: Do not treat DSN (Digital Serial Number) read failure as fatal.
  bnxt_en: Fix ipv6 RFS filter matching logic.
  bnxt_en: Fix NTUPLE firmware command failures.
  net: systemport: Fixed queue mapping in internal ring map
  net: dsa: bcm_sf2: Configure IMP port for 2Gb/sec
  net: dsa: sja1105: Don't error out on disabled ports with no phy-mode
  net: phy: dp83867: Set FORCE_LINK_GOOD to default after reset
  net: hns: fix soft lockup when there is not enough memory
  net: avoid updating qdisc_xmit_lock_key in netdev_update_lockdep_key()
  net/sched: act_ife: initalize ife->metalist earlier
  netfilter: nat: fix ICMP header corruption on ICMP errors
  net: wan: lapbether.c: Use built-in RCU list checking
  netfilter: nf_tables: fix flowtable list del corruption
  netfilter: nf_tables: fix memory leak in nf_tables_parse_netdev_hooks()
  netfilter: nf_tables: remove WARN and add NLA_STRING upper limits
  netfilter: nft_tunnel: ERSPAN_VERSION must not be null
  netfilter: nft_tunnel: fix null-attribute check
  ...

Pull i2c fixes from Wolfram Sang:
 "Two runtime PM fixes and one leak fix"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: iop3xx: Fix memory leak in probe error path
  i2c: tegra: Properly disable runtime PM on driver's probe error
  i2c: tegra: Fix suspending in active runtime PM state

A queue can't belong to multiple traffic classes. So, reject
any such configuration that results in overlapped queues for a
traffic class.

Fixes: b1396c2b ("cxgb4: parse and configure TC-MQPRIO offload")
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

T6 can support 2 egress traffic management channels per port to
double the total number of traffic classes that can be configured.
In this configuration, if the class belongs to the other channel,
then all the queues must be bound again explicitly to the new class,
for the rate limit parameters on the other channel to take effect.

So, always explicitly bind all queues to the port rate limit traffic
class, regardless of the traffic management channel that it belongs
to. Also, only bind queues to port rate limit traffic class, if all
the queues don't already belong to an existing different traffic
class.

Fixes: 4ec4762d ("cxgb4: add TC-MATCHALL classifier egress offload")
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Implement a cleanup method to properly free ci->params

BUG: memory leak
unreferenced object 0xffff88811746e2c0 (size 64):
  comm "syz-executor617", pid 7106, jiffies 4294943055 (age 14.250s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    c0 34 60 84 ff ff ff ff 00 00 00 00 00 00 00 00  .4`.............
  backtrace:
    [<0000000015aa236f>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline]
    [<0000000015aa236f>] slab_post_alloc_hook mm/slab.h:586 [inline]
    [<0000000015aa236f>] slab_alloc mm/slab.c:3320 [inline]
    [<0000000015aa236f>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3549
    [<000000002c946bd1>] kmalloc include/linux/slab.h:556 [inline]
    [<000000002c946bd1>] kzalloc include/linux/slab.h:670 [inline]
    [<000000002c946bd1>] tcf_ctinfo_init+0x21a/0x530 net/sched/act_ctinfo.c:236
    [<0000000086952cca>] tcf_action_init_1+0x400/0x5b0 net/sched/act_api.c:944
    [<000000005ab29bf8>] tcf_action_init+0x135/0x1c0 net/sched/act_api.c:1000
    [<00000000392f56f9>] tcf_action_add+0x9a/0x200 net/sched/act_api.c:1410
    [<0000000088f3c5dd>] tc_ctl_action+0x14d/0x1bb net/sched/act_api.c:1465
    [<000000006b39d986>] rtnetlink_rcv_msg+0x178/0x4b0 net/core/rtnetlink.c:5424
    [<00000000fd6ecace>] netlink_rcv_skb+0x61/0x170 net/netlink/af_netlink.c:2477
    [<0000000047493d02>] rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5442
    [<00000000bdcf8286>] netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
    [<00000000bdcf8286>] netlink_unicast+0x223/0x310 net/netlink/af_netlink.c:1328
    [<00000000fc5b92d9>] netlink_sendmsg+0x2c0/0x570 net/netlink/af_netlink.c:1917
    [<00000000da84d076>] sock_sendmsg_nosec net/socket.c:639 [inline]
    [<00000000da84d076>] sock_sendmsg+0x54/0x70 net/socket.c:659
    [<0000000042fb2eee>] ____sys_sendmsg+0x2d0/0x300 net/socket.c:2330
    [<000000008f23f67e>] ___sys_sendmsg+0x8a/0xd0 net/socket.c:2384
    [<00000000d838e4f6>] __sys_sendmsg+0x80/0xf0 net/socket.c:2417
    [<00000000289a9cb1>] __do_sys_sendmsg net/socket.c:2426 [inline]
    [<00000000289a9cb1>] __se_sys_sendmsg net/socket.c:2424 [inline]
    [<00000000289a9cb1>] __x64_sys_sendmsg+0x23/0x30 net/socket.c:2424

Fixes: 24ec483c ("net: sched: Introduce act_ctinfo action")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Kevin 'ldir' Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Kevin 'ldir' Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

The existing __lshrti3 was really inefficient, and the other two helpers
are also needed to compile some modules.

Add the missing versions, and export all of the symbols like arm64
already does.

This code is based on the assembly generated by libgcc builds.

This fixes a build break triggered by ubsan:

riscv64-unknown-linux-gnu-ld: lib/ubsan.o: in function `.L2':
ubsan.c:(.text.unlikely+0x38): undefined reference to `__ashlti3'
riscv64-unknown-linux-gnu-ld: ubsan.c:(.text.unlikely+0x42): undefined reference to `__ashrti3'
Signed-off-by: Olof Johansson <olof@lixom.net>
[paul.walmsley@sifive.com: use SYM_FUNC_{START,END} instead of
 ENTRY/ENDPROC; note libgcc origin]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>

Pull MTD fixes from Miquel Raynal:
 "Raw NAND:
   - GPMI: Fix the suspend/resume

  SPI-NOR:
   - Fix quad enable on Spansion like flashes
   - Fix selection of 4-byte addressing opcodes on Spansion"

* tag 'mtd/fixes-for-5.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux:
  mtd: rawnand: gpmi: Restore nfc timing setup after suspend/resume
  mtd: rawnand: gpmi: Fix suspend/resume problem
  mtd: spi-nor: Fix quad enable for Spansion like flashes
  mtd: spi-nor: Fix selection of 4-byte addressing opcodes on Spansion

Pull drm fixes from Dave Airlie:
 "Back from LCA2020, fixes wasn't too busy last week, seems to have
  quieten down appropriately, some amdgpu, i915, then a core mst fix and
  one fix for virtio-gpu and one for rockchip:

  core mst:
   - serialize down messages and clear timeslots are on unplug

  amdgpu:
   - Update golden settings for renoir
   - eDP fix

  i915:
   - uAPI fix: Remove dash and colon from PMU names to comply with
     tools/perf
   - Fix for include file that was indirectly included
   - Two fixes to make sure VMA are marked active for error capture

  virtio:
   - maintain obj reservation lock when submitting cmds

  rockchip:
   - increase link rate var size to accommodate rates"

* tag 'drm-fixes-2020-01-19' of git://anongit.freedesktop.org/drm/drm:
  drm/amd/display: Reorder detect_edp_sink_caps before link settings read.
  drm/amdgpu: update goldensetting for renoir
  drm/dp_mst: Have DP_Tx send one msg at a time
  drm/dp_mst: clear time slots for ports invalid
  drm/i915/pmu: Do not use colons or dashes in PMU names
  drm/rockchip: fix integer type used for storing dp data rate
  drm/i915/gt: Mark ring->vma as active while pinned
  drm/i915/gt: Mark context->state vma as active while pinned
  drm/i915/gt: Skip trying to unbind in restore_ggtt_mappings
  drm/i915: Add missing include file <linux/math64.h>
  drm/virtio: add missing virtio_gpu_array_lock_resv call

Temporary files used in the VDSO build process linger on even after make
mrproper: vdso-dummy.o.tmp, vdso.so.dbg.tmp.

Delete them once they're no longer needed.
Signed-off-by: Ilie Halip <ilie.halip@gmail.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>

Pull x86 fixes from Ingo Molnar:
 "Misc fixes:

   - a resctrl fix for uninitialized objects found by debugobjects

   - a resctrl memory leak fix

   - fix the unintended re-enabling of the of SME and SEV CPU flags if
     memory encryption was disabled at bootup via the MSR space"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/CPU/AMD: Ensure clearing of SME/SEV features is maintained
  x86/resctrl: Fix potential memory leak
  x86/resctrl: Fix an imbalance in domain_remove_cpu()

Pull timer fixes from Ingo Molnar:
 "Three fixes: fix link failure on Alpha, fix a Sparse warning and
  annotate/robustify a lockless access in the NOHZ code"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tick/sched: Annotate lockless access to last_jiffies_update
  lib/vdso: Make __cvdso_clock_getres() static
  time/posix-stubs: Provide compat itimer supoprt for alpha

Pull cpu/SMT fix from Ingo Molnar:
 "Fix a build bug on CONFIG_HOTPLUG_SMT=y && !CONFIG_SYSFS kernels"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu/SMT: Fix x86 link error without CONFIG_SYSFS

Pull x86 RAS fix from Ingo Molnar:
 "Fix a thermal throttling race that can result in easy to trigger boot
  crashes on certain Ice Lake platforms"

* 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce/therm_throt: Do not access uninitialized therm_work

Pull perf fixes from Ingo Molnar:
 "Tooling fixes, three Intel uncore driver fixes, plus an AUX events fix
  uncovered by the perf fuzzer"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/uncore: Remove PCIe3 unit for SNR
  perf/x86/intel/uncore: Fix missing marker for snr_uncore_imc_freerunning_events
  perf/x86/intel/uncore: Add PCI ID of IMC for Xeon E3 V5 Family
  perf: Correctly handle failed perf_get_aux_event()
  perf hists: Fix variable name's inconsistency in hists__for_each() macro
  perf map: Set kmap->kmaps backpointer for main kernel map chunks
  perf report: Fix incorrectly added dimensions as switch perf data file
  tools lib traceevent: Fix memory leakage in filter_event

Pull locking fixes from Ingo Molnar:
 "Three fixes:

    - Fix an rwsem spin-on-owner crash, introduced in v5.4

    - Fix a lockdep bug when running out of stack_trace entries,
      introduced in v5.4

    - Docbook fix"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/rwsem: Fix kernel crash when spinning on RWSEM_OWNER_UNKNOWN
  futex: Fix kernel-doc notation warning
  locking/lockdep: Fix buffer overrun problem in stack_trace[]

Pull irq fix from Ingo Molnar:
 "Fix a recent regression in the Ingenic SoCs irqchip driver that floods
  the syslog"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/ingenic: Get rid of the legacy IRQ domain

Pull EFI fixes from Ingo Molnar:
 "Three EFI fixes:

   - Fix a slow-boot-scrolling regression but making sure we use WC for
     EFI earlycon framebuffer mappings on x86

   - Fix a mixed EFI mode boot crash

   - Disable paging explicitly before entering startup_32() in mixed
     mode bootup"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/efistub: Disable paging at mixed mode entry
  efi/libstub/random: Initialize pointer variables to zero for mixed mode
  efi/earlycon: Fix write-combine mapping on x86

Pull rseq fixes from Ingo Molnar:
 "Two rseq bugfixes:

   - CLONE_VM !CLONE_THREAD didn't work properly, the kernel would end
     up corrupting the TLS of the parent. Technically a change in the
     ABI but the previous behavior couldn't resonably have been relied
     on by applications so this looks like a valid exception to the ABI
     rule.

   - Make the RSEQ_FLAG_UNREGISTER ABI behavior consistent with the
     handling of other flags. This is not thought to impact any
     applications either"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rseq: Unregister rseq for clone CLONE_VM
  rseq: Reject unknown flags on rseq unregister

Pull thread fixes from Christian Brauner:
 "Here is an urgent fix for ptrace_may_access() permission checking.

  Commit 69f594a3 ("ptrace: do not audit capability check when
  outputing /proc/pid/stat") introduced the ability to opt out of audit
  messages for accesses to various proc files since they are not
  violations of policy.

  While doing so it switched the check from ns_capable() to
  has_ns_capability{_noaudit}(). That means it switched from checking
  the subjective credentials (ktask->cred) of the task to using the
  objective credentials (ktask->real_cred). This is appears to be wrong.
  ptrace_has_cap() is currently only used in ptrace_may_access() And is
  used to check whether the calling task (subject) has the
  CAP_SYS_PTRACE capability in the provided user namespace to operate on
  the target task (object). According to the cred.h comments this means
  the subjective credentials of the calling task need to be used.

  With this fix we switch ptrace_has_cap() to use security_capable() and
  thus back to using the subjective credentials.

  As one example where this might be particularly problematic, Jann
  pointed out that in combination with the upcoming IORING_OP_OPENAT{2}
  feature, this bug might allow unprivileged users to bypass the
  capability checks while asynchronously opening files like /proc/*/mem,
  because the capability checks for this would be performed against
  kernel credentials.

  To illustrate on the former point about this being exploitable: When
  io_uring creates a new context it records the subjective credentials
  of the caller. Later on, when it starts to do work it creates a kernel
  thread and registers a callback. The callback runs with kernel creds
  for ktask->real_cred and ktask->cred.

  To prevent this from becoming a full-blown 0-day io_uring will call
  override_cred() and override ktask->cred with the subjective
  credentials of the creator of the io_uring instance. With
  ptrace_has_cap() currently looking at ktask->real_cred this override
  will be ineffective and the caller will be able to open arbitray proc
  files as mentioned above.

  Luckily, this is currently not exploitable but would be so once
  IORING_OP_OPENAT{2} land in v5.6. Let's fix it now.

  To minimize potential regressions I successfully ran the criu
  testsuite. criu makes heavy use of ptrace() and extensively hits
  ptrace_may_access() codepaths and has a good change of detecting any
  regressions.

  Additionally, I succesfully ran the ptrace and seccomp kernel tests"

* tag 'for-linus-2020-01-18' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  ptrace: reintroduce usage of subjective credentials in ptrace_has_cap()

Pull s390 fixes from Vasily Gorbik:

 - Fix printing misleading Secure-IPL enabled message when it is not.

 - Fix a race condition between host ap bus and guest ap bus doing
   device reset in crypto code.

 - Fix sanity check in CCA cipher key function (CCA AES cipher key
   support), which fails otherwise.

* tag 's390-5.5-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/setup: Fix secure ipl message
  s390/zcrypt: move ap device reset from bus to driver code
  s390/zcrypt: Fix CCA cipher key gen with clear key value function

Pull SCSI fixes from James Bottomley:
 "Three fixes in drivers with no impact to core code.

  The mptfusion fix is enormous because the driver API had to be
  rethreaded to pass down the necessary iocp pointer, but once that's
  done a significant chunk of code is deleted.

  The other two patches are small"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: mptfusion: Fix double fetch bug in ioctl
  scsi: storvsc: Correctly set number of hardware queues for IDE disk
  scsi: fnic: fix invalid stack access

Pull char/misc fixes from Greg KH:
 "Here are some small fixes for 5.5-rc7

  Included here are:

   -  two lkdtm fixes

   -  coresight build fix

   -  Documentation update for the hw process document

  All of these have been in linux-next with no reported issues"

* tag 'char-misc-5.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  Documentation/process: Add Amazon contact for embargoed hardware issues
  lkdtm/bugs: fix build error in lkdtm_UNSET_SMEP
  lkdtm/bugs: Make double-fault test always available
  coresight: etm4x: Fix unused function warning

Pull staging and IIO driver fixes from Greg KH:
 "Here are some small staging and iio driver fixes for 5.5-rc7

  All of them are for some small reported issues. Nothing major, full
  details in the shortlog.

  All have been in linux-next with no reported issues"

* tag 'staging-5.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: comedi: ni_routes: allow partial routing information
  staging: comedi: ni_routes: fix null dereference in ni_find_route_source()
  iio: light: vcnl4000: Fix scale for vcnl4040
  iio: buffer: align the size of scan bytes to size of the largest element
  iio: chemical: pms7003: fix unmet triggered buffer dependency
  iio: imu: st_lsm6dsx: Fix selection of ST_LSM6DS3_ID
  iio: adc: ad7124: Fix DT channel configuration

Pull USB driver fixes from Greg KH:
 "Here are some small USB driver and core fixes for 5.5-rc7

  There's one fix for hub wakeup issues and a number of small usb-serial
  driver fixes and device id updates.

  The hub fix has been in linux-next for a while with no reported
  issues, and the usb-serial ones have all passed 0-day with no
  problems"

* tag 'usb-5.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  USB: serial: quatech2: handle unbound ports
  USB: serial: keyspan: handle unbound ports
  USB: serial: io_edgeport: add missing active-port sanity check
  USB: serial: io_edgeport: handle unbound ports on URB completion
  USB: serial: ch341: handle unbound port at reset_resume
  USB: serial: suppress driver bind attributes
  USB: serial: option: add support for Quectel RM500Q in QDL mode
  usb: core: hub: Improved device recognition on remote wakeup
  USB: serial: opticon: fix control-message timeouts
  USB: serial: option: Add support for Quectel RM500Q
  USB: serial: simple: Add Motorola Solutions TETRA MTP3xxx and MTP85xx

Michael Chan says:

====================
bnxt_en: Bug fixes.

3 small bug fix patches.  The 1st two are aRFS fixes and the last one
fixes a fatal driver load failure on some kernels without PCIe
extended config space support enabled.

Please also queue these for -stable.  Thanks.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

DSN read can fail, for example on a kdump kernel without PCIe extended
config space support.  If DSN read fails, don't set the
BNXT_FLAG_DSN_VALID flag and continue loading.  Check the flag
to see if the stored DSN is valid before using it.  Only VF reps
creation should fail without valid DSN.

Fixes: 03213a99 ("bnxt: move bp->switch_id initialization to PF probe")
Reported-by: Marc Smith <msmith626@gmail.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix bnxt_fltr_match() to match ipv6 source and destination addresses.
The function currently only checks ipv4 addresses and will not work
corrently on ipv6 filters.

Fixes: c0c050c5 ("bnxt_en: New Broadcom ethernet driver.")
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The NTUPLE related firmware commands are sent to the wrong firmware
channel, causing all these commands to fail on new firmware that
supports the new firmware channel.  Fix it by excluding the 3
NTUPLE firmware commands from the list for the new firmware channel.

Fixes: 760b6d33 ("bnxt_en: Add support for 2nd firmware message channel.")
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit 69f594a3 ("ptrace: do not audit capability check when outputing /proc/pid/stat")
introduced the ability to opt out of audit messages for accesses to various
proc files since they are not violations of policy.  While doing so it
somehow switched the check from ns_capable() to
has_ns_capability{_noaudit}(). That means it switched from checking the
subjective credentials of the task to using the objective credentials. This
is wrong since. ptrace_has_cap() is currently only used in
ptrace_may_access() And is used to check whether the calling task (subject)
has the CAP_SYS_PTRACE capability in the provided user namespace to operate
on the target task (object). According to the cred.h comments this would
mean the subjective credentials of the calling task need to be used.
This switches ptrace_has_cap() to use security_capable(). Because we only
call ptrace_has_cap() in ptrace_may_access() and in there we already have a
stable reference to the calling task's creds under rcu_read_lock() there's
no need to go through another series of dereferences and rcu locking done
in ns_capable{_noaudit}().

As one example where this might be particularly problematic, Jann pointed
out that in combination with the upcoming IORING_OP_OPENAT feature, this
bug might allow unprivileged users to bypass the capability checks while
asynchronously opening files like /proc/*/mem, because the capability
checks for this would be performed against kernel credentials.

To illustrate on the former point about this being exploitable: When
io_uring creates a new context it records the subjective credentials of the
caller. Later on, when it starts to do work it creates a kernel thread and
registers a callback. The callback runs with kernel creds for
ktask->real_cred and ktask->cred. To prevent this from becoming a
full-blown 0-day io_uring will call override_cred() and override
ktask->cred with the subjective credentials of the creator of the io_uring
instance. With ptrace_has_cap() currently looking at ktask->real_cred this
override will be ineffective and the caller will be able to open arbitray
proc files as mentioned above.
Luckily, this is currently not exploitable but will turn into a 0-day once
IORING_OP_OPENAT{2} land in v5.6. Fix it now!

Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: stable@vger.kernel.org
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Reviewed-by: Jann Horn <jannh@google.com>
Fixes: 69f594a3 ("ptrace: do not audit capability check when outputing /proc/pid/stat")
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

virtio: maintain obj reservation lock when submitting cmds (Gerd)
rockchip: increase link rate var size to accommodate rates (Tobias)
mst: serialize down messages and clear timeslots are on unplug (Wayne)

Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Tobias Schramm <t.schramm@manjaro.org>
Cc: Wayne Lin <Wayne.Lin@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Sean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20200116162856.GA11524@art_vandelay

Merge tag 'drm-intel-fixes-2020-01-16' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

- uAPI fix: Remove dash and colon from PMU names to comply with tools/perf
- Fix for include file that was indirectly included
- Two fixes to make sure VMA are marked active for error capture
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200116161419.GA13594@jlahtine-desk.ger.corp.intel.com

As we reset the GPMI block at resume, the timing parameters setup by a
previous exec_op is lost.  Rewriting GPMI timing registers on first exec_op
after resume fixes the problem.

Fixes: ef347c0c ("mtd: rawnand: gpmi: Implement exec_op")
Cc: stable@vger.kernel.org
Signed-off-by: Esben Haabendal <esben@geanix.com>
Acked-by: Han Xu <han.xu@nxp.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

On system resume, the gpmi clock must be enabled before accessing gpmi
block.  Without this, resume causes something like

[  661.348790] gpmi_reset_block(5cbb0f7e): module reset timeout
[  661.348889] gpmi-nand 1806000.gpmi-nand: Error setting GPMI : -110
[  661.348928] PM: dpm_run_callback(): platform_pm_resume+0x0/0x44 returns -110
[  661.348961] PM: Device 1806000.gpmi-nand failed to resume: error -110

Fixes: ef347c0c ("mtd: rawnand: gpmi: Implement exec_op")
Cc: stable@vger.kernel.org
Signed-off-by: Esben Haabendal <esben@geanix.com>
Acked-by: Han Xu <han.xu@nxp.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

The commit 7b678c69 ("mtd: spi-nor: Merge spansion Quad Enable
methods") forgot to actually set the QE bit in some cases. Thus this
breaks quad mode accesses to flashes which support readback of the
status register-2. Fix it.

Fixes: 7b678c69 ("mtd: spi-nor: Merge spansion Quad Enable methods")
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

mtd->size is still unassigned when running spansion_post_sfdp_fixups()
hook, therefore use nor->params.size to determine the size of flash device.

This makes sure that 4-byte addressing opcodes are used on Spansion
flashes that are larger than 16MiB and don't have SFDP 4BAIT table
populated.

Fixes: 92094ebc ("mtd: spi-nor: Add spansion_post_sfdp_fixups()")
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>