linux-stable.git/include/linux, branch v5.10.80

arch/cc: Introduce a function to check for confidential computing features

2021-11-18T13:04:32+00:00

commit 46b49b12f3fc5e1347dba37d4639e2165f447871 upstream.

In preparation for other confidential computing technologies, introduce
a generic helper function, cc_platform_has(), that can be used to
check for specific active confidential computing attributes, like
memory encryption. This is intended to eliminate having to add multiple
technology-specific checks to the code (e.g. if (sev_active() ||
tdx_active() || ... ).

 [ bp: s/_CC_PLATFORM_H/_LINUX_CC_PLATFORM_H/g ]

Co-developed-by: Andi Kleen 
Signed-off-by: Andi Kleen 
Co-developed-by: Kuppuswamy Sathyanarayanan 
Signed-off-by: Kuppuswamy Sathyanarayanan 
Signed-off-by: Tom Lendacky 
Signed-off-by: Borislav Petkov 
Link: https://lkml.kernel.org/r/20210928191009.32551-3-bp@alien8.de
Signed-off-by: Greg Kroah-Hartman

posix-cpu-timers: Clear task::posix_cputimers_work in copy_process()

2021-11-18T13:04:29+00:00

commit ca7752caeaa70bd31d1714af566c9809688544af upstream.

copy_process currently copies task_struct.posix_cputimers_work as-is. If a
timer interrupt arrives while handling clone and before dup_task_struct
completes then the child task will have:

1. posix_cputimers_work.scheduled = true
2. posix_cputimers_work.work queued.

copy_process clears task_struct.task_works, so (2) will have no effect and
posix_cpu_timers_work will never run (not to mention it doesn't make sense
for two tasks to share a common linked list).

Since posix_cpu_timers_work never runs, posix_cputimers_work.scheduled is
never cleared. Since scheduled is set, future timer interrupts will skip
scheduling work, with the ultimate result that the task will never receive
timer expirations.

Together, the complete flow is:

1. Task 1 calls clone(), enters kernel.
2. Timer interrupt fires, schedules task work on Task 1.
   2a. task_struct.posix_cputimers_work.scheduled = true
   2b. task_struct.posix_cputimers_work.work added to
       task_struct.task_works.
3. dup_task_struct() copies Task 1 to Task 2.
4. copy_process() clears task_struct.task_works for Task 2.
5. Future timer interrupts on Task 2 see
   task_struct.posix_cputimers_work.scheduled = true and skip scheduling
   work.

Fix this by explicitly clearing contents of task_struct.posix_cputimers_work
in copy_process(). This was never meant to be shared or inherited across
tasks in the first place.

Fixes: 1fb497dd0030 ("posix-cpu-timers: Provide mechanisms to defer timer handling to task_work")
Reported-by: Rhys Hiltner 
Signed-off-by: Michael Pratt 
Signed-off-by: Thomas Gleixner 
Cc: 
Link: https://lore.kernel.org/r/20211101210615.716522-1-mpratt@google.com
Signed-off-by: Greg Kroah-Hartman

seq_file: fix passing wrong private data

2021-11-18T13:04:27+00:00

[ Upstream commit 10a6de19cad6efb9b49883513afb810dc265fca2 ]

DEFINE_PROC_SHOW_ATTRIBUTE() is supposed to be used to define a series
of functions and variables to register proc file easily. And the users
can use proc_create_data() to pass their own private data and get it
via seq->private in the callback. Unfortunately, the proc file system
use PDE_DATA() to get private data instead of inode->i_private. So fix
it. Fortunately, there only one user of it which does not pass any
private data, so this bug does not break any in-tree codes.

Link: https://lkml.kernel.org/r/20211029032638.84884-1-songmuchun@bytedance.com
Fixes: 97a32539b956 ("proc: convert everything to "struct proc_ops"")
Signed-off-by: Muchun Song 
Cc: Andy Shevchenko 
Cc: Stephen Rothwell 
Cc: Florent Revest 
Cc: Alexey Dobriyan 
Cc: Christian Brauner 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

ethtool: fix ethtool msg len calculation for pause stats

2021-11-18T13:04:25+00:00

[ Upstream commit 1aabe578dd86e9f2867c4db4fba9a15f4ba1825d ]

ETHTOOL_A_PAUSE_STAT_MAX is the MAX attribute id,
so we need to subtract non-stats and add one to
get a count (IOW -2+1 == -1).

Otherwise we'll see:

  ethnl cmd 21: calculated reply length 40, but consumed 52

Fixes: 9a27a33027f2 ("ethtool: add standard pause stats")
Signed-off-by: Jakub Kicinski 
Reviewed-by: Saeed Mahameed 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

NFS: Fix up commit deadlocks

2021-11-18T13:04:23+00:00

[ Upstream commit 133a48abf6ecc535d7eddc6da1c3e4c972445882 ]

If O_DIRECT bumps the commit_info rpcs_out field, then that could lead
to fsync() hangs. The fix is to ensure that O_DIRECT calls
nfs_commit_end().

Fixes: 723c921e7dfc ("sched/wait, fs/nfs: Convert wait_on_atomic_t() usage to the new wait_var_event() API")
Signed-off-by: Trond Myklebust 
Signed-off-by: Sasha Levin

rpmsg: Fix rpmsg_create_ept return when RPMSG config is not defined

2021-11-18T13:04:22+00:00

[ Upstream commit 537d3af1bee8ad1415fda9b622d1ea6d1ae76dfa ]

According to the description of the rpmsg_create_ept in rpmsg_core.c
the function should return NULL on error.

Fixes: 2c8a57088045 ("rpmsg: Provide function stubs for API")
Signed-off-by: Arnaud Pouliquen 
Reviewed-by: Mathieu Poirier 
Link: https://lore.kernel.org/r/20210712123912.10672-1-arnaud.pouliquen@foss.st.com
Signed-off-by: Bjorn Andersson 
Signed-off-by: Sasha Levin

tpm: fix Atmel TPM crash caused by too frequent queries

2021-11-18T13:04:11+00:00

[ Upstream commit 79ca6f74dae067681a779fd573c2eb59649989bc ]

The Atmel TPM 1.2 chips crash with error
`tpm_try_transmit: send(): error -62` since kernel 4.14.
It is observed from the kernel log after running `tpm_sealdata -z`.
The error thrown from the command is as follows
```
$ tpm_sealdata -z
Tspi_Key_LoadKey failed: 0x00001087 - layer=tddl,
code=0087 (135), I/O error
```

The issue was reproduced with the following Atmel TPM chip:
```
$ tpm_version
T0  TPM 1.2 Version Info:
  Chip Version:        1.2.66.1
  Spec Level:          2
  Errata Revision:     3
  TPM Vendor ID:       ATML
  TPM Version:         01010000
  Manufacturer Info:   41544d4c
```

The root cause of the issue is due to the TPM calls to msleep()
were replaced with usleep_range() [1], which reduces
the actual timeout. Via experiments, it is observed that
the original msleep(5) actually sleeps for 15ms.
Because of a known timeout issue in Atmel TPM 1.2 chip,
the shorter timeout than 15ms can cause the error described above.

A few further changes in kernel 4.16 [2] and 4.18 [3, 4] further
reduced the timeout to less than 1ms. With experiments,
the problematic timeout in the latest kernel is the one
for `wait_for_tpm_stat`.

To fix it, the patch reverts the timeout of `wait_for_tpm_stat`
to 15ms for all Atmel TPM 1.2 chips, but leave it untouched
for Ateml TPM 2.0 chip, and chips from other vendors.
As explained above, the chosen 15ms timeout is
the actual timeout before this issue introduced,
thus the old value is used here.
Particularly, TPM_ATML_TIMEOUT_WAIT_STAT_MIN is set to 14700us,
TPM_ATML_TIMEOUT_WAIT_STAT_MIN is set to 15000us according to
the existing TPM_TIMEOUT_RANGE_US (300us).
The fixed has been tested in the system with the affected Atmel chip
with no issues observed after boot up.

References:
[1] 9f3fc7bcddcb tpm: replace msleep() with usleep_range() in TPM
1.2/2.0 generic drivers
[2] cf151a9a44d5 tpm: reduce tpm polling delay in tpm_tis_core
[3] 59f5a6b07f64 tpm: reduce poll sleep time in tpm_transmit()
[4] 424eaf910c32 tpm: reduce polling time to usecs for even finer
granularity

Fixes: 9f3fc7bcddcb ("tpm: replace msleep() with usleep_range() in TPM 1.2/2.0 generic drivers")
Link: https://patchwork.kernel.org/project/linux-integrity/patch/20200926223150.109645-1-hao.wu@rubrik.com/
Signed-off-by: Hao Wu 
Reviewed-by: Jarkko Sakkinen 
Signed-off-by: Jarkko Sakkinen 
Signed-off-by: Sasha Levin

kernel/sched: Fix sched_fork() access an invalid sched_task_group

2021-11-18T13:04:07+00:00

[ Upstream commit 4ef0c5c6b5ba1f38f0ea1cedad0cad722f00c14a ]

There is a small race between copy_process() and sched_fork()
where child->sched_task_group point to an already freed pointer.

	parent doing fork()      | someone moving the parent
				 | to another cgroup
  -------------------------------+-------------------------------
  copy_process()
      + dup_task_struct()<1>
				  parent move to another cgroup,
				  and free the old cgroup. <2>
      + sched_fork()
	+ __set_task_cpu()<3>
	+ task_fork_fair()
	  + sched_slice()<4>

In the worst case, this bug can lead to "use-after-free" and
cause panic as shown above:

  (1) parent copy its sched_task_group to child at <1>;

  (2) someone move the parent to another cgroup and free the old
      cgroup at <2>;

  (3) the sched_task_group and cfs_rq that belong to the old cgroup
      will be accessed at <3> and <4>, which cause a panic:

  [] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
  [] PGD 8000001fa0a86067 P4D 8000001fa0a86067 PUD 2029955067 PMD 0
  [] Oops: 0000 [#1] SMP PTI
  [] CPU: 7 PID: 648398 Comm: ebizzy Kdump: loaded Tainted: G           OE    --------- -  - 4.18.0.x86_64+ #1
  [] RIP: 0010:sched_slice+0x84/0xc0

  [] Call Trace:
  []  task_fork_fair+0x81/0x120
  []  sched_fork+0x132/0x240
  []  copy_process.part.5+0x675/0x20e0
  []  ? __handle_mm_fault+0x63f/0x690
  []  _do_fork+0xcd/0x3b0
  []  do_syscall_64+0x5d/0x1d0
  []  entry_SYSCALL_64_after_hwframe+0x65/0xca
  [] RIP: 0033:0x7f04418cd7e1

Between cgroup_can_fork() and cgroup_post_fork(), the cgroup
membership and thus sched_task_group can't change. So update child's
sched_task_group at sched_post_fork() and move task_fork() and
__set_task_cpu() (where accees the sched_task_group) from sched_fork()
to sched_post_fork().

Fixes: 8323f26ce342 ("sched: Fix race in task_group")
Signed-off-by: Zhang Qiao 
Signed-off-by: Peter Zijlstra (Intel) 
Acked-by: Tejun Heo 
Link: https://lkml.kernel.org/r/20210915064030.2231-1-zhangqiao22@huawei.com
Signed-off-by: Sasha Levin

task_stack: Fix end_of_stack() for architectures with upwards-growing stack

2021-11-18T13:04:01+00:00

[ Upstream commit 9cc2fa4f4a92ccc6760d764e7341be46ee8aaaa1 ]

The function end_of_stack() returns a pointer to the last entry of a
stack. For architectures like parisc where the stack grows upwards
return the pointer to the highest address in the stack.

Without this change I faced a crash on parisc, because the stackleak
functionality wrote STACKLEAK_POISON to the lowest address and thus
overwrote the first 4 bytes of the task_struct which included the
TIF_FLAGS.

Signed-off-by: Helge Deller 
Signed-off-by: Sasha Levin

block: bump max plugged deferred size from 16 to 32

2021-11-18T13:03:57+00:00

[ Upstream commit ba0ffdd8ce48ad7f7e85191cd29f9674caca3745 ]

Particularly for NVMe with efficient deferred submission for many
requests, there are nice benefits to be seen by bumping the default max
plug count from 16 to 32. This is especially true for virtualized setups,
where the submit part is more expensive. But can be noticed even on
native hardware.

Reduce the multiple queue factor from 4 to 2, since we're changing the
default size.

While changing it, move the defines into the block layer private header.
These aren't values that anyone outside of the block layer uses, or
should use.

Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin