linux.git/drivers/misc, branch v4.9.113

vmw_balloon: fix inflation with batching

2018-07-17T09:37:51+00:00

commit 90d72ce079791399ac255c75728f3c9e747b093d upstream.

Embarrassingly, the recent fix introduced worse problem than it solved,
causing the balloon not to inflate. The VM informed the hypervisor that
the pages for lock/unlock are sitting in the wrong address, as it used
the page that is used the uninitialized page variable.

Fixes: b23220fe054e9 ("vmw_balloon: fixing double free when batching mode is off")
Cc: stable@vger.kernel.org
Reviewed-by: Xavier Deguillard 
Signed-off-by: Nadav Amit 
Signed-off-by: Greg Kroah-Hartman

ibmasm: don't write out of bounds in read handler

2018-07-17T09:37:51+00:00

commit a0341fc1981a950c1e902ab901e98f60e0e243f3 upstream.

This read handler had a lot of custom logic and wrote outside the bounds of
the provided buffer. This could lead to kernel and userspace memory
corruption. Just use simple_read_from_buffer() with a stack buffer.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Jann Horn 
Signed-off-by: Greg Kroah-Hartman

vmw_balloon: fixing double free when batching mode is off

2018-06-16T07:52:34+00:00

commit b23220fe054e92f616b82450fae8cd3ab176cc60 upstream.

The balloon.page field is used for two different purposes if batching is
on or off. If batching is on, the field point to the page which is used
to communicate with with the hypervisor. If it is off, balloon.page
points to the page that is about to be (un)locked.

Unfortunately, this dual-purpose of the field introduced a bug: when the
balloon is popped (e.g., when the machine is reset or the balloon driver
is explicitly removed), the balloon driver frees, unconditionally, the
page that is held in balloon.page.  As a result, if batching is
disabled, this leads to double freeing the last page that is sent to the
hypervisor.

The following error occurs during rmmod when kernel checkers are on, and
the balloon is not empty:

[   42.307653] ------------[ cut here ]------------
[   42.307657] Kernel BUG at ffffffffba1e4b28 [verbose debug info unavailable]
[   42.307720] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC
[   42.312512] Modules linked in: vmw_vsock_vmci_transport vsock ppdev joydev vmw_balloon(-) input_leds serio_raw vmw_vmci parport_pc shpchp parport i2c_piix4 nfit mac_hid autofs4 vmwgfx drm_kms_helper hid_generic syscopyarea sysfillrect usbhid sysimgblt fb_sys_fops hid ttm mptspi scsi_transport_spi ahci mptscsih drm psmouse vmxnet3 libahci mptbase pata_acpi
[   42.312766] CPU: 10 PID: 1527 Comm: rmmod Not tainted 4.12.0+ #5
[   42.312803] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 09/30/2016
[   42.313042] task: ffff9bf9680f8000 task.stack: ffffbfefc1638000
[   42.313290] RIP: 0010:__free_pages+0x38/0x40
[   42.313510] RSP: 0018:ffffbfefc163be98 EFLAGS: 00010246
[   42.313731] RAX: 000000000000003e RBX: ffffffffc02b9720 RCX: 0000000000000006
[   42.313972] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9bf97e08e0a0
[   42.314201] RBP: ffffbfefc163be98 R08: 0000000000000000 R09: 0000000000000000
[   42.314435] R10: 0000000000000000 R11: 0000000000000000 R12: ffffffffc02b97e4
[   42.314505] R13: ffffffffc02b9748 R14: ffffffffc02b9728 R15: 0000000000000200
[   42.314550] FS:  00007f3af5fec700(0000) GS:ffff9bf97e080000(0000) knlGS:0000000000000000
[   42.314599] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   42.314635] CR2: 00007f44f6f4ab24 CR3: 00000003a7d12000 CR4: 00000000000006e0
[   42.314864] Call Trace:
[   42.315774]  vmballoon_pop+0x102/0x130 [vmw_balloon]
[   42.315816]  vmballoon_exit+0x42/0xd64 [vmw_balloon]
[   42.315853]  SyS_delete_module+0x1e2/0x250
[   42.315891]  entry_SYSCALL_64_fastpath+0x23/0xc2
[   42.315924] RIP: 0033:0x7f3af5b0e8e7
[   42.315949] RSP: 002b:00007fffe6ce0148 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
[   42.315996] RAX: ffffffffffffffda RBX: 000055be676401e0 RCX: 00007f3af5b0e8e7
[   42.316951] RDX: 000000000000000a RSI: 0000000000000800 RDI: 000055be67640248
[   42.317887] RBP: 0000000000000003 R08: 0000000000000000 R09: 1999999999999999
[   42.318845] R10: 0000000000000883 R11: 0000000000000206 R12: 00007fffe6cdf130
[   42.319755] R13: 0000000000000000 R14: 0000000000000000 R15: 000055be676401e0
[   42.320606] Code: c0 74 1c f0 ff 4f 1c 74 02 5d c3 85 f6 74 07 e8 0f d8 ff ff 5d c3 31 f6 e8 c6 fb ff ff 5d c3 48 c7 c6 c8 0f c5 ba e8 58 be 02 00 <0f> 0b 66 0f 1f 44 00 00 66 66 66 66 90 48 85 ff 75 01 c3 55 48
[   42.323462] RIP: __free_pages+0x38/0x40 RSP: ffffbfefc163be98
[   42.325735] ---[ end trace 872e008e33f81508 ]---

To solve the bug, we eliminate the dual purpose of balloon.page.

Fixes: f220a80f0c2e ("VMware balloon: add batching to the vmw_balloon.")
Cc: stable@vger.kernel.org
Reported-by: Oleksandr Natalenko 
Signed-off-by: Gil Kupfer 
Signed-off-by: Nadav Amit 
Reviewed-by: Xavier Deguillard 
Tested-by: Oleksandr Natalenko 
Signed-off-by: Greg Kroah-Hartman

cxl: Unlock on error in probe

2018-04-13T17:48:22+00:00

[ Upstream commit 58d876fa7181f2f393190c1d32c056b5a9d34aa2 ]

We should unlock if get_cxl_adapter() fails.

Fixes: 594ff7d067ca ("cxl: Support to flash a new image on the adapter from a guest")
Signed-off-by: Dan Carpenter 
Acked-by: Frederic Barrat 
Signed-off-by: Michael Ellerman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

drivers/misc/vmw_vmci/vmci_queue_pair.c: fix a couple integer overflow tests

2018-04-13T17:47:53+00:00

[ Upstream commit 146180c052a00172f4dc08eaade836fd02f61fb5 ]

The "DIV_ROUND_UP(size, PAGE_SIZE)" operation can overflow if "size" is
more than ULLONG_MAX - PAGE_SIZE.

Link: http://lkml.kernel.org/r/20170322111950.GA11279@mwanda
Signed-off-by: Dan Carpenter 
Cc: Jorgen Hansen 
Cc: Masahiro Yamada 
Cc: Michal Hocko 
Cc: Greg Kroah-Hartman 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

mei: remove dev_err message on an unsupported ioctl

2018-04-08T10:12:57+00:00

commit bb0829a741792b56c908d7745bc0b2b540293bcc upstream.

Currently the driver spams the kernel log on unsupported ioctls which is
unnecessary as the ioctl returns -ENOIOCTLCMD to indicate this anyway.
I suspect this was originally for debugging purposes but it really is not
required so remove it.

Signed-off-by: Colin Ian King 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

lkdtm: turn off kcov for lkdtm_rodata_do_nothing:

2018-03-22T08:17:49+00:00

[ Upstream commit 7064dc7fc13b2994d33ae540ffb7a3a05ac463bf ]

I ran into a link error on ARM64 for lkdtm_rodata_do_nothing:

drivers/misc/built-in.o: In function `lkdtm_rodata_do_nothing':
:(.rodata+0x68c8): relocation truncated to fit: R_AARCH64_CALL26 against symbol `__sanitizer_cov_trace_pc' defined in .text section in kernel/built-in.o

I did not analyze this further, but my theory is that we would need a trampoline
to call __sanitizer_cov_trace_pc(), but the linker (correctly) only adds trampolines
for callers in executable sections.

Disabling KCOV for this one file avoids the build failure with no
other practical downsides I can think of.

The problem can only happen on kernels that contain both kcov and
lkdtm, so if we want to backport this, it should be in the earliest
version that has both (v4.8).

Fixes: 5c9a8750a640 ("kernel: add kcov code coverage")
Fixes: 9a49a528dcf3 ("lkdtm: add function for testing .rodata section")
Signed-off-by: Arnd Bergmann 
Acked-by: Dmitry Vyukov 
Acked-by: Kees Cook 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

scsi: ses: don't get power status of SES device slot on probe

2018-03-22T08:17:48+00:00

[ Upstream commit 75106523f39751390b5789b36ee1d213b3af1945 ]

The commit 08024885a2a3 ("ses: Add power_status to SES device slot")
introduced the 'power_status' attribute to enclosure components and
the associated callbacks.

There are 2 callbacks available to get the power status of a device:
1) ses_get_power_status() for 'struct enclosure_component_callbacks'
2) get_component_power_status() for the sysfs device attribute
(these are available for kernel-space and user-space, respectively.)

However, despite both methods being available to get power status
on demand, that commit also introduced a call to get power status
in ses_enclosure_data_process().

This dramatically increased the total probe time for SCSI devices
on larger configurations, because ses_enclosure_data_process() is
called several times during the SCSI devices probe and loops over
the component devices (but that is another problem, another patch).

That results in a tremendous continuous hammering of SCSI Receive
Diagnostics commands to the enclosure-services device, which does
delay the total probe time for the SCSI devices __significantly__:

  Originally, ~34 minutes on a system attached to ~170 disks:

    [ 9214.490703] mpt3sas version 13.100.00.00 loaded
    ...
    [11256.580231] scsi 17:0:177:0: qdepth(16), tagged(1), simple(0),
                   ordered(0), scsi_level(6), cmd_que(1)

  With this patch, it decreased to ~2.5 minutes -- a 13.6x faster

    [ 1002.992533] mpt3sas version 13.100.00.00 loaded
    ...
    [ 1151.978831] scsi 11:0:177:0: qdepth(16), tagged(1), simple(0),
                   ordered(0), scsi_level(6), cmd_que(1)

Back to the commit discussion.. on the ses_get_power_status() call
introduced in ses_enclosure_data_process(): impact of removing it.

That may possibly be in place to initialize the power status value
on device probe.  However, those 2 functions available to retrieve
that value _do_ automatically refresh/update it.  So the potential
benefit would be a direct access of the 'power_status' field which
does not use the callbacks...

But the only reader of 'struct enclosure_component::power_status'
is the get_component_power_status() callback for sysfs attribute,
and it _does_ check for and call the .get_power_status callback,
(which indeed is defined and implemented by that commit), so the
power status value is, again, automatically updated.

So, the remaining potential for a direct/non-callback access to
the power_status attribute would be out-of-tree modules -- well,
for those, if they are for whatever reason interested in values
that are set during device probe and not up-to-date by the time
they need it.. well, that would be curious.

Well, to handle that more properly, set the initial power state
value to '-1' (i.e., uninitialized) instead of '1' (power 'on'),
and check for it in that callback which may do an direct access
to the field value _if_ a callback function is not defined.

Signed-off-by: Mauricio Faria de Oliveira 
Fixes: 08024885a2a3 ("ses: Add power_status to SES device slot")
Reviewed-by: Dan Williams 
Reviewed-by: Song Liu 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

cxl: Check if vphb exists before iterating over AFU devices

2017-12-25T13:23:36+00:00

commit 12841f87b7a8ceb3d54f171660f72a86941bfcb3 upstream.

During an eeh a kernel-oops is reported if no vPHB is allocated to the
AFU. This happens as during AFU init, an error in creation of vPHB is
a non-fatal error. Hence afu->phb should always be checked for NULL
before iterating over it for the virtual AFU pci devices.

This patch fixes the kenel-oops by adding a NULL pointer check for
afu->phb before it is dereferenced.

Fixes: 9e8df8a21963 ("cxl: EEH support")
Signed-off-by: Vaibhav Jain 
Acked-by: Andrew Donnellan 
Acked-by: Frederic Barrat 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

eeprom: at24: change nvmem stride to 1

2017-12-20T09:07:17+00:00

commit 7f6d2ecd3d7acaf205ea7b3e96f9ffc55b92298b upstream.

Trying to read the MAC address from an eeprom that has an offset that
is not a multiple of 4 causes an error currently.

Fix it by changing the nvmem stride to 1.

Signed-off-by: David Lechner 
[Bartosz: tweaked the commit message]
Signed-off-by: Bartosz Golaszewski 
Signed-off-by: Greg Kroah-Hartman