linux.git/drivers/misc, branch v4.19.39

lkdtm: Add tests for NULL pointer dereference

2019-04-20T07:16:04+00:00

[ Upstream commit 59a12205d3c32aee4c13ca36889fdf7cfed31126 ]

Introduce lkdtm tests for NULL pointer dereference: check access or exec
at NULL address, since these errors tend to be reported differently from
the general fault error text. For example from x86:

    pr_alert("BUG: unable to handle kernel %s at %px\n",
        address < PAGE_SIZE ? "NULL pointer dereference" : "paging request",
        (void *)address);

Signed-off-by: Christophe Leroy 
Signed-off-by: Kees Cook 
Signed-off-by: Sasha Levin

lkdtm: Print real addresses

2019-04-20T07:16:03+00:00

[ Upstream commit 4c411157a42f122051ae3469bee0b5cabe89e139 ]

Today, when doing a lkdtm test before the readiness of the
random generator, (ptrval) is printed instead of the address
at which it perform the fault:

[ 1597.337030] lkdtm: Performing direct entry EXEC_USERSPACE
[ 1597.337142] lkdtm: attempting ok execution at (ptrval)
[ 1597.337398] lkdtm: attempting bad execution at (ptrval)
[ 1597.337460] kernel tried to execute user page (77858000) -exploit attempt? (uid: 0)
[ 1597.344769] Unable to handle kernel paging request for instruction fetch
[ 1597.351392] Faulting instruction address: 0x77858000
[ 1597.356312] Oops: Kernel access of bad area, sig: 11 [#1]

If the lkdtm test is done later on, it prints an hashed address.

In both cases this is pointless. The purpose of the test is to
ensure the kernel generates an Oops at the expected address,
so real addresses needs to be printed. This patch fixes that.

Signed-off-by: Christophe Leroy 
Signed-off-by: Kees Cook 
Signed-off-by: Sasha Levin

cxl: Wrap iterations over afu slices inside 'afu_list_lock'

2019-03-23T19:10:03+00:00

commit edeb304f659792fb5bab90d7d6f3408b4c7301fb upstream.

Within cxl module, iteration over array 'adapter->afu' may be racy
at few points as it might be simultaneously read during an EEH and its
contents being set to NULL while driver is being unloaded or unbound
from the adapter. This might result in a NULL pointer to 'struct afu'
being de-referenced during an EEH thereby causing a kernel oops.

This patch fixes this by making sure that all access to the array
'adapter->afu' is wrapped within the context of spin-lock
'adapter->afu_list_lock'.

Fixes: 9e8df8a21963 ("cxl: EEH support")
Cc: stable@vger.kernel.org # v4.3+
Acked-by: Andrew Donnellan 
Acked-by: Frederic Barrat 
Acked-by: Christophe Lombard 
Signed-off-by: Vaibhav Jain 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

mei: bus: move hw module get/put to probe/release

2019-03-23T19:09:39+00:00

commit b5958faa34e2f99f3475ad89c52d98dfea079d33 upstream.

Fix unbalanced module reference counting during internal reset, which
prevents the drivers unloading.
Tracking mei_me/txe modules on mei client bus via
mei_cldev_enable/disable is error prone due to possible internal
reset flow, where clients are disconnected underneath.
Moving reference counting to probe and release of mei bus client
driver solves this issue in simplest way, as each client provides only
a single connection to a client bus driver.

Cc: 
Signed-off-by: Alexander Usyskin 
Signed-off-by: Tomas Winkler 
Signed-off-by: Greg Kroah-Hartman

mei: hbm: clean the feature flags on link reset

2019-03-23T19:09:39+00:00

commit 37fd0b623023484ef6df79ed46f21f06ecc611ff upstream.

The list of supported functions can be altered upon link reset,
clean the flags to allow correct selections of supported
features.

Cc:  v4.19+
Signed-off-by: Alexander Usyskin 
Signed-off-by: Tomas Winkler 
Signed-off-by: Greg Kroah-Hartman

eeprom: at24: add support for 24c2048

2019-02-20T09:25:35+00:00

[ Upstream commit 37cf28d3b5bca1b532a0b6aac722e7f2788a9294 ]

Works with ST M24M02.

Signed-off-by: Adrian Bunk 
Signed-off-by: Bartosz Golaszewski 
Signed-off-by: Sasha Levin

mic: vop: Fix use-after-free on remove

2019-02-15T07:10:12+00:00

commit 70ed7148dadb812f2f7c9927e98ef3cf4869dfa9 upstream.

KASAN detects a use-after-free when vop devices are removed.

This problem was introduced by commit 0063e8bbd2b62d136 ("virtio_vop:
don't kfree device on register failure").  That patch moved the freeing
of the struct _vop_vdev to the release function, but failed to ensure
that vop holds a reference to the device when it doesn't want it to go
away.  A kfree() was replaced with a put_device() in the unregistration
path, but the last reference to the device is already dropped in
unregister_virtio_device() so the struct is freed before vop is done
with it.

Fix it by holding a reference until cleanup is done.  This is similar to
the fix in virtio_pci in commit 2989be09a8a9d6 ("virtio_pci: fix use
after free on release").

 ==================================================================
 BUG: KASAN: use-after-free in vop_scan_devices+0xc6c/0xe50 [vop]
 Read of size 8 at addr ffff88800da18580 by task kworker/0:1/12

 CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.0.0-rc4+ #53
 Workqueue: events vop_hotplug_devices [vop]
 Call Trace:
  dump_stack+0x74/0xbb
  print_address_description+0x5d/0x2b0
  ? vop_scan_devices+0xc6c/0xe50 [vop]
  kasan_report+0x152/0x1aa
  ? vop_scan_devices+0xc6c/0xe50 [vop]
  ? vop_scan_devices+0xc6c/0xe50 [vop]
  vop_scan_devices+0xc6c/0xe50 [vop]
  ? vop_loopback_free_irq+0x160/0x160 [vop_loopback]
  process_one_work+0x7c0/0x14b0
  ? pwq_dec_nr_in_flight+0x2d0/0x2d0
  ? do_raw_spin_lock+0x120/0x280
  worker_thread+0x8f/0xbf0
  ? __kthread_parkme+0x78/0xf0
  ? process_one_work+0x14b0/0x14b0
  kthread+0x2ae/0x3a0
  ? kthread_park+0x120/0x120
  ret_from_fork+0x3a/0x50

 Allocated by task 12:
  kmem_cache_alloc_trace+0x13a/0x2a0
  vop_scan_devices+0x473/0xe50 [vop]
  process_one_work+0x7c0/0x14b0
  worker_thread+0x8f/0xbf0
  kthread+0x2ae/0x3a0
  ret_from_fork+0x3a/0x50

 Freed by task 12:
  kfree+0x104/0x310
  device_release+0x73/0x1d0
  kobject_put+0x14f/0x420
  unregister_virtio_device+0x32/0x50
  vop_scan_devices+0x19d/0xe50 [vop]
  process_one_work+0x7c0/0x14b0
  worker_thread+0x8f/0xbf0
  kthread+0x2ae/0x3a0
  ret_from_fork+0x3a/0x50

 The buggy address belongs to the object at ffff88800da18008
  which belongs to the cache kmalloc-2k of size 2048
 The buggy address is located 1400 bytes inside of
  2048-byte region [ffff88800da18008, ffff88800da18808)
 The buggy address belongs to the page:
 page:ffffea0000368600 count:1 mapcount:0 mapping:ffff88801440dbc0 index:0x0 compound_mapcount: 0
 flags: 0x4000000000010200(slab|head)
 raw: 4000000000010200 ffffea0000378608 ffffea000037a008 ffff88801440dbc0
 raw: 0000000000000000 00000000000d000d 00000001ffffffff 0000000000000000
 page dumped because: kasan: bad access detected

 Memory state around the buggy address:
  ffff88800da18480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff88800da18500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 >ffff88800da18580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                    ^
  ffff88800da18600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff88800da18680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ==================================================================

Fixes: 0063e8bbd2b62d136 ("virtio_vop: don't kfree device on register failure")
Signed-off-by: Vincent Whitchurch 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

mei: me: add ice lake point device id.

2019-02-15T07:10:11+00:00

commit efe814e90b98aed6d655b5a4092b9114b8b26e42 upstream.

Add icelake mei device id.

Cc: 
Signed-off-by: Tomas Winkler 
Signed-off-by: Greg Kroah-Hartman

misc: vexpress: Off by one in vexpress_syscfg_exec()

2019-02-15T07:10:11+00:00

commit f8a70d8b889f180e6860cb1f85fed43d37844c5a upstream.

The > comparison should be >= to prevent reading beyond the end of the
func->template[] array.

(The func->template array is allocated in vexpress_syscfg_regmap_init()
and it has func->num_templates elements.)

Fixes: 974cc7b93441 ("mfd: vexpress: Define the device as MFD cells")
Signed-off-by: Dan Carpenter 
Acked-by: Sudeep Holla 
Signed-off-by: Greg Kroah-Hartman

misc: ibmvsm: Fix potential NULL pointer dereference

2019-01-31T07:14:35+00:00

commit e25df7812c91f62581301f9a7ac102acf92e4937 upstream.

There is a potential NULL pointer dereference in case kzalloc()
fails and returns NULL.

Fix this by adding a NULL check on *session*

Also, update the function header with information about the
expected return on failure and remove unnecessary variable rc.

This issue was detected with the help of Coccinelle.

Fixes: 0eca353e7ae7 ("misc: IBM Virtual Management Channel Driver (VMC)")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva 
Signed-off-by: Greg Kroah-Hartman