linux_dsm_epyc7002/drivers
Alexey Kardashevskiy 44c413d9a5 tty/vt: Do not warn when huge selection requested
The tty TIOCL_SETSEL ioctl allocates a memory buffer big enough for text
selection area. The maximum allowed console size is
VC_RESIZE_MAXCOL * VC_RESIZE_MAXROW == 32767*32767 == ~1GB and typical
MAX_ORDER is set to allow allocations lot less than than (circa 16MB).

So it is quite possible to trigger huge allocation (and syzkaller just
did that) which is going to fail (which is fine) with a backtrace in
mm/page_alloc.c at WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN)) and
this may trigger panic (if panic_on_warn is enabled) and
leak kernel addresses to dmesg.

This passes __GFP_NOWARN to kmalloc_array to avoid unnecessary user-
triggered WARN_ON. Note that the error is not ignored and
the warning is still printed.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Link: https://lore.kernel.org/r/20200617070444.116704-1-aik@ozlabs.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-01 15:29:35 +02:00
..
accessibility vc: separate state 2020-06-24 17:08:30 +02:00
acpi
amba
android
ata
atm
auxdisplay
base
bcma
block
bluetooth
bus
cdrom
char
clk
clocksource
connector
counter
cpufreq
cpuidle
crypto
dax
dca
devfreq
dio
dma
dma-buf
edac
eisa
extcon
firewire
firmware
fpga
fsi
gnss
gpio
gpu
greybus
hid
hsi
hv
hwmon
hwspinlock
hwtracing
i2c
i3c
ide
idle
iio
infiniband
input
interconnect
iommu
ipack
irqchip
isdn
leds
lightnvm
macintosh
mailbox
mcb
md
media
memory
memstick
message
mfd
misc
mmc
most
mtd
mux
net
nfc
ntb
nubus
nvdimm
nvme
nvmem
of
opp
oprofile
parisc
parport
pci
pcmcia
perf
phy
pinctrl
platform
pnp
power
powercap
pps
ps3
ptp
pwm
rapidio
ras
regulator
remoteproc
reset
rpmsg
rtc
s390
sbus
scsi
sfi
sh
siox
slimbus
soc
soundwire
spi
spmi
ssb
staging vc: separate state 2020-06-24 17:08:30 +02:00
target
tc
tee
thermal
thunderbolt
tty tty/vt: Do not warn when huge selection requested 2020-07-01 15:29:35 +02:00
uio
usb vt: use newly defined CUR_* macros 2020-06-24 17:08:33 +02:00
vdpa
vfio
vhost
video vt: use newly defined CUR_* macros 2020-06-24 17:08:33 +02:00
virt
virtio
visorbus
vlynq
vme
w1
watchdog
xen
zorro
Kconfig
Makefile