linux-stable.git/drivers, branch v4.4.183

coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping

2019-06-22T06:18:27+00:00

commit 04f5866e41fb70690e28397487d8bd8eea7d712a upstream.

The core dumping code has always run without holding the mmap_sem for
writing, despite that is the only way to ensure that the entire vma
layout will not change from under it.  Only using some signal
serialization on the processes belonging to the mm is not nearly enough.
This was pointed out earlier.  For example in Hugh's post from Jul 2017:

  https://lkml.kernel.org/r/alpine.LSU.2.11.1707191716030.2055@eggly.anvils

  "Not strictly relevant here, but a related note: I was very surprised
   to discover, only quite recently, how handle_mm_fault() may be called
   without down_read(mmap_sem) - when core dumping. That seems a
   misguided optimization to me, which would also be nice to correct"

In particular because the growsdown and growsup can move the
vm_start/vm_end the various loops the core dump does around the vma will
not be consistent if page faults can happen concurrently.

Pretty much all users calling mmget_not_zero()/get_task_mm() and then
taking the mmap_sem had the potential to introduce unexpected side
effects in the core dumping code.

Adding mmap_sem for writing around the ->core_dump invocation is a
viable long term fix, but it requires removing all copy user and page
faults and to replace them with get_dump_page() for all binary formats
which is not suitable as a short term fix.

For the time being this solution manually covers the places that can
confuse the core dump either by altering the vma layout or the vma flags
while it runs.  Once ->core_dump runs under mmap_sem for writing the
function mmget_still_valid() can be dropped.

Allowing mmap_sem protected sections to run in parallel with the
coredump provides some minor parallelism advantage to the swapoff code
(which seems to be safe enough by never mangling any vma field and can
keep doing swapins in parallel to the core dumping) and to some other
corner case.

In order to facilitate the backporting I added "Fixes: 86039bd3b4e6"
however the side effect of this same race condition in /proc/pid/mem
should be reproducible since before 2.6.12-rc2 so I couldn't add any
other "Fixes:" because there's no hash beyond the git genesis commit.

Because find_extend_vma() is the only location outside of the process
context that could modify the "mm" structures under mmap_sem for
reading, by adding the mmget_still_valid() check to it, all other cases
that take the mmap_sem for reading don't need the new check after
mmget_not_zero()/get_task_mm().  The expand_stack() in page fault
context also doesn't need the new check, because all tasks under core
dumping are frozen.

Link: http://lkml.kernel.org/r/20190325224949.11068-1-aarcange@redhat.com
Fixes: 86039bd3b4e6 ("userfaultfd: add new syscall to provide memory externalization")
Signed-off-by: Andrea Arcangeli 
Reported-by: Jann Horn 
Suggested-by: Oleg Nesterov 
Acked-by: Peter Xu 
Reviewed-by: Mike Rapoport 
Reviewed-by: Oleg Nesterov 
Reviewed-by: Jann Horn 
Acked-by: Jason Gunthorpe 
Acked-by: Michal Hocko 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Cc: Joel Fernandes (Google) 
[mhocko@suse.com: stable 4.4 backport
 - drop infiniband part because of missing 5f9794dc94f59
 - drop userfaultfd_event_wait_completion hunk because of
   missing 9cd75c3cd4c3d]
 - handle binder_update_page_range because of missing 720c241924046
 - handle mlx5_ib_disassociate_ucontext - akaher@vmware.com
]
Signed-off-by: Michal Hocko 
Signed-off-by: Greg Kroah-Hartman

Revert "crypto: crypto4xx - properly set IV after de- and encrypt"

2019-06-22T06:18:26+00:00

This reverts commit e9a60ab1609a7d975922adad1bf9c46ac6954584 which is
commit fc340115ffb8235c1bbd200c28855e6373d0dd1a upstream.

Hauke writes that this breaks the build and should be reverted.

Reported-by: Hauke Mehrtens 
Cc: Christian Lamparter 
Cc: Herbert Xu 
Cc: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

scsi: libsas: delete sas port if expander discover failed

2019-06-22T06:18:26+00:00

[ Upstream commit 3b0541791453fbe7f42867e310e0c9eb6295364d ]

The sas_port(phy->port) allocated in sas_ex_discover_expander() will not be
deleted when the expander failed to discover. This will cause resource leak
and a further issue of kernel BUG like below:

[159785.843156]  port-2:17:29: trying to add phy phy-2:17:29 fails: it's
already part of another port
[159785.852144] ------------[ cut here  ]------------
[159785.856833] kernel BUG at drivers/scsi/scsi_transport_sas.c:1086!
[159785.863000] Internal error: Oops - BUG: 0 [#1] SMP
[159785.867866] CPU: 39 PID: 16993 Comm: kworker/u96:2 Tainted: G
W  OE     4.19.25-vhulk1901.1.0.h111.aarch64 #1
[159785.878458] Hardware name: Huawei Technologies Co., Ltd.
Hi1620EVBCS/Hi1620EVBCS, BIOS Hi1620 CS B070 1P TA 03/21/2019
[159785.889231] Workqueue: 0000:74:02.0_disco_q sas_discover_domain
[159785.895224] pstate: 40c00009 (nZcv daif +PAN +UAO)
[159785.900094] pc : sas_port_add_phy+0x188/0x1b8
[159785.904524] lr : sas_port_add_phy+0x188/0x1b8
[159785.908952] sp : ffff0001120e3b80
[159785.912341] x29: ffff0001120e3b80 x28: 0000000000000000
[159785.917727] x27: ffff802ade8f5400 x26: ffff0000681b7560
[159785.923111] x25: ffff802adf11a800 x24: ffff0000680e8000
[159785.928496] x23: ffff802ade8f5728 x22: ffff802ade8f5708
[159785.933880] x21: ffff802adea2db40 x20: ffff802ade8f5400
[159785.939264] x19: ffff802adea2d800 x18: 0000000000000010
[159785.944649] x17: 00000000821bf734 x16: ffff00006714faa0
[159785.950033] x15: ffff0000e8ab4ecf x14: 7261702079646165
[159785.955417] x13: 726c612073277469 x12: ffff00006887b830
[159785.960802] x11: ffff00006773eaa0 x10: 7968702079687020
[159785.966186] x9 : 0000000000002453 x8 : 726f702072656874
[159785.971570] x7 : 6f6e6120666f2074 x6 : ffff802bcfb21290
[159785.976955] x5 : ffff802bcfb21290 x4 : 0000000000000000
[159785.982339] x3 : ffff802bcfb298c8 x2 : 337752b234c2ab00
[159785.987723] x1 : 337752b234c2ab00 x0 : 0000000000000000
[159785.993108] Process kworker/u96:2 (pid: 16993, stack limit =
0x0000000072dae094)
[159786.000576] Call trace:
[159786.003097]  sas_port_add_phy+0x188/0x1b8
[159786.007179]  sas_ex_get_linkrate.isra.5+0x134/0x140
[159786.012130]  sas_ex_discover_expander+0x128/0x408
[159786.016906]  sas_ex_discover_dev+0x218/0x4c8
[159786.021249]  sas_ex_discover_devices+0x9c/0x1a8
[159786.025852]  sas_discover_root_expander+0x134/0x160
[159786.030802]  sas_discover_domain+0x1b8/0x1e8
[159786.035148]  process_one_work+0x1b4/0x3f8
[159786.039230]  worker_thread+0x54/0x470
[159786.042967]  kthread+0x134/0x138
[159786.046269]  ret_from_fork+0x10/0x18
[159786.049918] Code: 91322300 f0004402 91178042 97fe4c9b (d4210000)
[159786.056083] Modules linked in: hns3_enet_ut(OE) hclge(OE) hnae3(OE)
hisi_sas_test_hw(OE) hisi_sas_test_main(OE) serdes(OE)
[159786.067202] ---[ end trace 03622b9e2d99e196  ]---
[159786.071893] Kernel panic - not syncing: Fatal exception
[159786.077190] SMP: stopping secondary CPUs
[159786.081192] Kernel Offset: disabled
[159786.084753] CPU features: 0x2,a2a00a38

Fixes: 2908d778ab3e ("[SCSI] aic94xx: new driver")
Reported-by: Jian Luo 
Signed-off-by: Jason Yan 
CC: John Garry 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

scsi: libcxgbi: add a check for NULL pointer in cxgbi_check_route()

2019-06-22T06:18:26+00:00

[ Upstream commit cc555759117e8349088e0c5d19f2f2a500bafdbd ]

ip_dev_find() can return NULL so add a check for NULL pointer.

Signed-off-by: Varun Prakash 
Signed-off-by: Martin K. Petersen 
Signed-off-by: Sasha Levin

net: sh_eth: fix mdio access in sh_eth_close() for R-Car Gen2 and RZ/A1 SoCs

2019-06-22T06:18:26+00:00

[ Upstream commit 315ca92dd863fecbffc0bb52ae0ac11e0398726a ]

The sh_eth_close() resets the MAC and then calls phy_stop()
so that mdio read access result is incorrect without any error
according to kernel trace like below:

ifconfig-216   [003] .n..   109.133124: mdio_access: ee700000.ethernet-ffffffff read  phy:0x01 reg:0x00 val:0xffff

According to the hardware manual, the RMII mode should be set to 1
before operation the Ethernet MAC. However, the previous code was not
set to 1 after the driver issued the soft_reset in sh_eth_dev_exit()
so that the mdio read access result seemed incorrect. To fix the issue,
this patch adds a condition and set the RMII mode register in
sh_eth_dev_exit() for R-Car Gen2 and RZ/A1 SoCs.

Note that when I have tried to move the sh_eth_dev_exit() calling
after phy_stop() on sh_eth_close(), but it gets worse (kernel panic
happened and it seems that a register is accessed while the clock is
off).

Signed-off-by: Yoshihiro Shimoda 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

i2c: dev: fix potential memory leak in i2cdev_ioctl_rdwr

2019-06-22T06:18:26+00:00

[ Upstream commit a0692f0eef91354b62c2b4c94954536536be5425 ]

If I2C_M_RECV_LEN check failed, msgs[i].buf allocated by memdup_user
will not be freed. Pump index up so it will be freed.

Fixes: 838bfa6049fb ("i2c-dev: Add support for I2C_M_RECV_LEN")
Signed-off-by: Yingjoe Chen 
Signed-off-by: Wolfram Sang 
Signed-off-by: Sasha Levin

net: tulip: de4x5: Drop redundant MODULE_DEVICE_TABLE()

2019-06-22T06:18:26+00:00

[ Upstream commit 3e66b7cc50ef921121babc91487e1fb98af1ba6e ]

Building with Clang reports the redundant use of MODULE_DEVICE_TABLE():

drivers/net/ethernet/dec/tulip/de4x5.c:2110:1: error: redefinition of '__mod_eisa__de4x5_eisa_ids_device_table'
MODULE_DEVICE_TABLE(eisa, de4x5_eisa_ids);
^
./include/linux/module.h:229:21: note: expanded from macro 'MODULE_DEVICE_TABLE'
extern typeof(name) __mod_##type##__##name##_device_table               \
                    ^
:90:1: note: expanded from here
__mod_eisa__de4x5_eisa_ids_device_table
^
drivers/net/ethernet/dec/tulip/de4x5.c:2100:1: note: previous definition is here
MODULE_DEVICE_TABLE(eisa, de4x5_eisa_ids);
^
./include/linux/module.h:229:21: note: expanded from macro 'MODULE_DEVICE_TABLE'
extern typeof(name) __mod_##type##__##name##_device_table               \
                    ^
:85:1: note: expanded from here
__mod_eisa__de4x5_eisa_ids_device_table
^

This drops the one further from the table definition to match the common
use of MODULE_DEVICE_TABLE().

Fixes: 07563c711fbc ("EISA bus MODALIAS attributes support")
Signed-off-by: Kees Cook 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

gpio: fix gpio-adp5588 build errors

2019-06-22T06:18:26+00:00

[ Upstream commit e9646f0f5bb62b7d43f0968f39d536cfe7123b53 ]

The gpio-adp5588 driver uses interfaces that are provided by
GPIOLIB_IRQCHIP, so select that symbol in its Kconfig entry.

Fixes these build errors:

../drivers/gpio/gpio-adp5588.c: In function ‘adp5588_irq_handler’:
../drivers/gpio/gpio-adp5588.c:266:26: error: ‘struct gpio_chip’ has no member named ‘irq’
            dev->gpio_chip.irq.domain, gpio));
                          ^
../drivers/gpio/gpio-adp5588.c: In function ‘adp5588_irq_setup’:
../drivers/gpio/gpio-adp5588.c:298:2: error: implicit declaration of function ‘gpiochip_irqchip_add_nested’ [-Werror=implicit-function-declaration]
  ret = gpiochip_irqchip_add_nested(&dev->gpio_chip,
  ^
../drivers/gpio/gpio-adp5588.c:307:2: error: implicit declaration of function ‘gpiochip_set_nested_irqchip’ [-Werror=implicit-function-declaration]
  gpiochip_set_nested_irqchip(&dev->gpio_chip,
  ^

Fixes: 459773ae8dbb ("gpio: adp5588-gpio: support interrupt controller")
Reported-by: kbuild test robot 
Signed-off-by: Randy Dunlap 
Cc: linux-gpio@vger.kernel.org
Reviewed-by: Bartosz Golaszewski 
Acked-by: Michael Hennerich 
Signed-off-by: Linus Walleij 
Signed-off-by: Sasha Levin

mISDN: make sure device name is NUL terminated

2019-06-22T06:18:25+00:00

[ Upstream commit ccfb62f27beb295103e9392462b20a6ed807d0ea ]

The user can change the device_name with the IMSETDEVNAME ioctl, but we
need to ensure that the user's name is NUL terminated.  Otherwise it
could result in a buffer overflow when we copy the name back to the user
with IMGETDEVINFO ioctl.

I also changed two strcpy() calls which handle the name to strscpy().
Hopefully, there aren't any other ways to create a too long name, but
it's nice to do this as a kernel hardening measure.

Signed-off-by: Dan Carpenter 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

sunhv: Fix device naming inconsistency between sunhv_console and sunhv_reg

2019-06-22T06:18:25+00:00

[ Upstream commit 07a6d63eb1b54b5fb38092780fe618dfe1d96e23 ]

In d5a2aa24, the name in struct console sunhv_console was changed from "ttyS"
to "ttyHV" while the name in struct uart_ops sunhv_pops remained unchanged.

This results in the hypervisor console device to be listed as "ttyHV0" under
/proc/consoles while the device node is still named "ttyS0":

root@osaka:~# cat /proc/consoles
ttyHV0               -W- (EC p  )    4:64
tty0                 -WU (E     )    4:1
root@osaka:~# readlink /sys/dev/char/4:64
../../devices/root/f02836f0/f0285690/tty/ttyS0
root@osaka:~#

This means that any userland code which tries to determine the name of the
device file of the hypervisor console device can not rely on the information
provided by /proc/consoles. In particular, booting current versions of debian-
installer inside a SPARC LDOM will fail with the installer unable to determine
the console device.

After renaming the device in struct uart_ops sunhv_pops to "ttyHV" as well,
the inconsistency is fixed and it is possible again to determine the name
of the device file of the hypervisor console device by reading the contents
of /proc/console:

root@osaka:~# cat /proc/consoles
ttyHV0               -W- (EC p  )    4:64
tty0                 -WU (E     )    4:1
root@osaka:~# readlink /sys/dev/char/4:64
../../devices/root/f02836f0/f0285690/tty/ttyHV0
root@osaka:~#

With this change, debian-installer works correctly when installing inside
a SPARC LDOM.

Signed-off-by: John Paul Adrian Glaubitz 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman