linux/drivers
David Hildenbrand 60858c00e5 device-dax: don't leak kernel memory to user space after unloading kmem
Assume we have kmem configured and loaded:

  [root@localhost ~]# cat /proc/iomem
  ...
  140000000-33fffffff : Persistent Memory$
    140000000-1481fffff : namespace0.0
    150000000-33fffffff : dax0.0
      150000000-33fffffff : System RAM

Assume we try to unload kmem. This force-unloading will work, even if
memory cannot get removed from the system.

  [root@localhost ~]# rmmod kmem
  [   86.380228] removing memory fails, because memory [0x0000000150000000-0x0000000157ffffff] is onlined
  ...
  [   86.431225] kmem dax0.0: DAX region [mem 0x150000000-0x33fffffff] cannot be hotremoved until the next reboot

Now, we can reconfigure the namespace:

  [root@localhost ~]# ndctl create-namespace --force --reconfig=namespace0.0 --mode=devdax
  [  131.409351] nd_pmem namespace0.0: could not reserve region [mem 0x140000000-0x33fffffff]dax
  [  131.410147] nd_pmem: probe of namespace0.0 failed with error -16namespace0.0 --mode=devdax
  ...

This fails as expected due to the busy memory resource, and the memory
cannot be used.  However, the dax0.0 device is removed, and along its
name.

The name of the memory resource now points at freed memory (name of the
device):

  [root@localhost ~]# cat /proc/iomem
  ...
  140000000-33fffffff : Persistent Memory
    140000000-1481fffff : namespace0.0
    150000000-33fffffff : �_�^7_��/_��wR��WQ���^��� ...
    150000000-33fffffff : System RAM

We have to make sure to duplicate the string.  While at it, remove the
superfluous setting of the name and fixup a stale comment.

Fixes: 9f960da72b ("device-dax: "Hotremove" persistent memory that is used like normal RAM")
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: <stable@vger.kernel.org>	[5.3]
Link: http://lkml.kernel.org/r/20200508084217.9160-2-david@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-23 10:26:31 -07:00
..
accessibility
acpi ACPI: EC: PM: Avoid flushing EC work when EC GPE is inactive 2020-05-18 13:15:13 +02:00
amba amba: Initialize dma_parms for amba devices 2020-04-28 17:44:34 +02:00
android Merge 5.6-rc7 into char-misc-next 2020-03-23 07:59:38 +01:00
ata ata: sata_inic162x fix a spelling issue 2020-04-23 09:59:30 -06:00
atm .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
auxdisplay Merge 5.6-rc7 into char-misc-next 2020-03-23 07:59:38 +01:00
base driver core: Ensure wait_for_device_probe() waits until the deferred_probe_timeout fires 2020-04-28 17:57:13 +02:00
bcma
block block-5.7-2020-05-22 2020-05-22 11:10:42 -07:00
bluetooth Bluetooth: btusb: print Intel fw build version in power-on boot 2020-03-16 08:57:40 +01:00
bus bus: mhi: core: Fix channel device name conflict 2020-05-05 16:59:54 +02:00
cdrom
char Convert i2c_new_device() to i2c_new_client_device() 2020-05-17 16:07:30 -07:00
clk clk: ti: clkctrl: convert subclocks to use proper names also 2020-05-12 20:18:19 -07:00
clocksource clocksource/drivers/timer-vf-pit: Add missing parenthesis 2020-04-05 09:24:58 +02:00
connector
counter counter: 104-quad-8: Add lock guards - generic interface 2020-04-19 17:50:00 +01:00
cpufreq cpufreq: intel_pstate: Only mention the BIOS disabling turbo mode once 2020-04-27 10:30:11 +02:00
cpuidle Merge branch 'pm-cpuidle' 2020-04-10 11:32:22 +02:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-05-06 20:53:22 -07:00
dax device-dax: don't leak kernel memory to user space after unloading kmem 2020-05-23 10:26:31 -07:00
dca
devfreq PM / devfreq: Fix handling dev_pm_qos_remove_request result 2020-03-25 08:35:03 +09:00
dio
dma dmaengine: tegra210-adma: Fix an error handling path in 'tegra_adma_probe()' 2020-05-19 22:26:01 +05:30
dma-buf dma-buf: fix documentation build warnings 2020-04-30 19:47:39 +05:30
edac Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2020-03-30 16:40:08 -07:00
eisa .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
extcon Char/Misc driver patches for 5.7-rc1 2020-04-03 13:22:40 -07:00
firewire
firmware gcc-10: mark more functions __init to avoid section mismatch warnings 2020-05-09 17:50:03 -07:00
fpga fpga: dfl: pci: fix return value of cci_pci_sriov_configure 2020-03-30 20:45:30 -07:00
fsi
gnss
gpio gpio: tegra: mask GPIO IRQs during IRQ shutdown 2020-04-28 16:22:33 +02:00
gpu Just one meson patch this time to propagate an error code 2020-05-15 16:00:57 +10:00
greybus
hid HID: quirks: Add HID_QUIRK_NO_INIT_REPORTS quirk for Dell K12A keyboard-dock 2020-05-04 11:24:58 +02:00
hsi
hv hyperv-fixes for 5.7-rc4 2020-04-27 13:28:27 -07:00
hwmon hwmon: (da9052) Synchronize access with mfd 2020-05-13 10:06:09 -07:00
hwspinlock hwspinlock: hwspinlock_internal.h: Replace zero-length array with flexible-array member 2020-03-25 22:30:46 -07:00
hwtracing intel_th: msu: Make stopping the trace optional 2020-03-24 13:45:24 +01:00
i2c i2c: mux: demux-pinctrl: Fix an error handling path in 'i2c_demux_pinctrl_probe()' 2020-05-15 11:23:49 +02:00
i3c i3c: convert to use i2c_new_client_device() 2020-03-29 10:35:50 +02:00
ide drivers/ide: Fix build regression. 2020-04-04 18:07:59 -07:00
idle Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2020-03-30 16:40:08 -07:00
iio First set of IIO fixes for the 5.7 cycle. 2020-04-20 14:07:00 +02:00
infiniband RDMA/uverbs: Move IB_EVENT_DEVICE_FATAL to destroy_uobj 2020-05-12 17:02:25 -03:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2020-04-07 20:20:12 -07:00
interconnect interconnect: qcom: Move the static keyword to the front of declaration 2020-04-29 13:11:44 +02:00
iommu iommu: Fix deferred domain attachment 2020-05-19 15:05:43 +02:00
ipack
irqchip Merge branch 'irq/gic-v4.1-fixes-5.7' into irq/irqchip-5.7 2020-04-17 08:59:55 +01:00
isdn mISDN: make dmril and dmrim static 2020-04-16 13:52:31 -07:00
leds leds: core: Fix warning message when init_data 2020-04-06 23:12:08 +02:00
lightnvm for-5.7/drivers-2020-03-29 2020-03-30 11:43:51 -07:00
macintosh Char/Misc driver patches for 5.7-rc1 2020-04-03 13:22:40 -07:00
mailbox mailbox: imx: add SCU MU support 2020-03-19 23:04:32 -05:00
mcb
md - Document DM integrity allow_discard feature that was added during 2020-04-30 16:45:08 -07:00
media Power management updates for 5.7-rc1 2020-03-30 15:05:01 -07:00
memory ARM: driver updates 2020-04-03 15:05:35 -07:00
memstick
message scsi: message: fusion: Replace zero-length array with flexible-array member 2020-03-26 22:40:47 -04:00
mfd mfd: intel-lpss: Fix Intel Elkhart Lake LPSS I2C input clock 2020-03-30 07:35:28 +01:00
misc mei: me: disable mei interface on LBG servers. 2020-05-05 16:56:41 +02:00
mmc mmc: sdhci-acpi: Add SDHCI_QUIRK2_BROKEN_64_BIT_DMA for AMDI0040 2020-05-11 10:51:30 +02:00
most most: core: use function subsys_initcall() 2020-04-28 15:04:09 +02:00
mtd This pull request contains the following bug fixes for MTD: 2020-05-20 13:23:55 -07:00
mux
net dpaa2-eth: properly handle buffer size restrictions 2020-05-15 10:30:47 -07:00
nfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-03-25 18:58:11 -07:00
ntb pci-v5.7-changes 2020-04-03 14:25:02 -07:00
nubus
nvdimm libnvdimm for 5.7 2020-04-08 21:03:40 -07:00
nvme nvme-pci: dma read memory barrier for completions 2020-05-12 18:02:24 +02:00
nvmem nvmem: core: remove nvmem_sysfs_get_groups() 2020-03-25 19:23:49 +01:00
of of: unittest: kmemleak in duplicate property update 2020-04-17 08:31:34 -05:00
opp opp: Manage empty OPP tables with clk handle 2020-04-13 16:14:55 +05:30
oprofile
parisc parisc: Replace setup_irq() by request_irq() 2020-04-05 22:05:23 +02:00
parport
pci PCI: Move Apex Edge TPU class quirk to fix BAR assignment 2020-04-14 19:16:51 -05:00
pcmcia pcmcia: remove some unused space characters 2020-03-31 18:48:22 +02:00
perf arm64 updates for 5.7: 2020-03-31 10:05:01 -07:00
phy phy: qualcomm: usb-hs-28nm: Prepare clocks in init 2020-04-30 12:10:49 +05:30
pinctrl pinctrl: qcom: Add affinity callbacks to msmgpio IRQ chip 2020-05-12 14:29:29 +02:00
platform chrome-platform fixes for v5.7-rc5 2020-05-06 16:40:14 -07:00
pnp
power change email address for Pali Rohár 2020-04-10 15:36:22 -07:00
powercap Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2020-03-30 16:40:08 -07:00
pps
ps3 powerpc/ps3: Remove an unneeded NULL check 2020-04-03 00:09:59 +11:00
ptp ptp: Remove unneeded conversion to bool 2020-04-21 15:45:32 -07:00
pwm pwm: pca9685: Fix PWM/GPIO inter-operation 2020-04-03 21:41:42 +02:00
rapidio
ras
regulator regulator: Revert "Use driver_deferred_probe_timeout for regulator_init_complete_work" 2020-04-29 19:57:45 +02:00
remoteproc remoteproc fixes for v5.7 2020-04-23 09:28:15 -07:00
reset
rpmsg rpmsg: pull in slab.h 2020-04-17 06:05:29 -04:00
rtc - New Drivers 2020-04-07 19:48:52 -07:00
s390 s390/ism: fix error return code in ism_probe() 2020-05-13 12:14:51 -07:00
sbus misc: move FLASH_MINOR into miscdevice.h and fix conflicts 2020-03-18 12:27:04 +01:00
scsi scsi: ibmvscsi: Fix WARN_ON during event pool release 2020-04-28 22:59:55 -04:00
sfi
sh
siox
slimbus
soc arm64: soc: ZynqMP SoC fixes for v5.7 2020-04-21 14:21:20 +02:00
soundwire Char/Misc driver patches for 5.7-rc1 2020-04-03 13:22:40 -07:00
spi sound updates for 5.7-rc1 2020-04-02 15:50:04 -07:00
spmi
ssb
staging staging: gasket: Check the return value of gasket_get_bar_index() 2020-05-05 12:36:05 +02:00
target scsi: target/iblock: fix WRITE SAME zeroing 2020-04-22 00:02:13 -04:00
tc
tee ARM: driver updates 2020-04-03 15:05:35 -07:00
thermal - Convert tsens configuration DT binding to yaml (Rajeshwari) 2020-04-07 20:00:16 -07:00
thunderbolt thunderbolt: Check return value of tb_sw_read() in usb4_switch_op() 2020-04-28 19:00:59 +02:00
tty TTY/Serial fixes for 5.7-rc5 2020-05-08 08:56:16 -07:00
uio uio: uio_pdrv_genirq: use new devm_uio_register_device() function 2020-03-18 12:34:10 +01:00
usb USB: gadget: fix illegal array access in binding with UDC 2020-05-15 15:42:17 +02:00
vdpa vdpasim: remove unused variable 'ret' 2020-05-11 06:44:12 -04:00
vfio vfio/type1: Fix VA->PA translation for PFNMAP VMAs in vaddr_get_pfn() 2020-04-23 12:10:01 -06:00
vhost virtio: build warning fixes 2020-05-21 12:59:29 -07:00
video drm fixes for 5.7-rc1 2020-04-07 20:24:34 -07:00
virt virt: vbox: Use fallthrough; 2020-03-19 07:41:03 +01:00
virtio virtio-balloon: Avoid using the word 'report' when referring to free page hinting 2020-04-17 06:05:30 -04:00
visorbus
vlynq
vme
w1
watchdog watchdog: sp805: fix restart handler 2020-04-08 11:18:38 +02:00
xen xen: branch for v5.7-rc2 2020-04-17 10:35:17 -07:00
zorro SPDX patches for 5.7-rc1. 2020-04-03 13:12:26 -07:00
Kconfig virtio: fixes, vdpa 2020-04-08 10:51:53 -07:00
Makefile virtio: fixes, vdpa 2020-04-08 10:51:53 -07:00