Centos-kernel-stream-9/drivers
Max Kellermann f17c403af9 media: dvbdev: add a mutex protecting the "mdev" pointer
During destruction, a race condition in
dvb_media_controller_disable_source() can cause a kernel crash,
because the "mdev" pointer has been read successfully while another
task executes dvb_usb_media_device_unregister(), which destroys the
object.  Example for such a crash:

    general protection fault: 0000 [#1] SMP
    CPU: 1 PID: 301 Comm: vdr Not tainted 4.8.1-nuc+ #102
    [142B blob data]
    task: ffff8802301f2040 task.stack: ffff880233728000
    RIP: 0010:[<ffffffff816c296b>]  [<ffffffff816c296b>] dvb_frontend_release+0xcb/0x120
    RSP: 0018:ffff88023372bdd8  EFLAGS: 00010202
    RAX: 001fd55c000000da RBX: ffff880236bad810 RCX: 0000000000000000
    RDX: ffff880235bd81f0 RSI: 0000000000000246 RDI: ffff880235bd81e8
    RBP: ffff88023372be00 R08: 0000000000000000 R09: 0000000000000000
    R10: 0000000000000000 R11: ffff88022f009910 R12: 0000000000000000
    R13: ffff880235a21a80 R14: ffff880235bd8000 R15: ffff880235bb8a78
    FS:  0000000000000000(0000) GS:ffff88023fd00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 00007f96edd69818 CR3: 0000000002406000 CR4: 00000000001006e0
    Stack:
     ffff88022f009900 0000000000000008 ffff880235bb8a78 ffff8802344fbb20
     ffff880236437b40 ffff88023372be48 ffffffff8117a81e ffff880235bb8a78
     ffff88022f009910 ffff8802335a7400 ffff8802301f2040 ffff88022f009900
    Call Trace:
     [<ffffffff8117a81e>] __fput+0xde/0x1d0
     [<ffffffff8117a949>] ____fput+0x9/0x10
     [<ffffffff810a9fce>] task_work_run+0x7e/0xa0
     [<ffffffff81094bab>] do_exit+0x27b/0xa50
     [<ffffffff810407e3>] ? __do_page_fault+0x1c3/0x430
     [<ffffffff81095402>] do_group_exit+0x42/0xb0
     [<ffffffff8109547f>] SyS_exit_group+0xf/0x10
     [<ffffffff8108bedb>] entry_SYSCALL_64_fastpath+0x13/0x8f
    Code: 31 c9 49 8d be e8 01 00 00 ba 01 00 00 00 be 03 00 00 00 e8 68 2d a0 ff 48 8b 83 10 03 00 00 48 8b 80 88 00 00 00 48 85 c0 74 12 <48> 8b 80 88 02 00 00 48 85 c0 74 06 49 8b 7d
    RIP  [<ffffffff816c296b>] dvb_frontend_release+0xcb/0x120

[mchehab+samsung@kernel.org: fix a Coding Style issue]
Signed-off-by: Max Kellermann <max.kellermann@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2018-05-11 12:09:59 -04:00
..
accessibility
acpi
amba
android
ata
atm
auxdisplay
base
bcma
block
bluetooth
bus
cdrom
char
clk
clocksource
connector
cpufreq
cpuidle
crypto
dax
dca
devfreq
dio
dma
dma-buf
edac
eisa
extcon
firewire
firmware
fmc
fpga
fsi
gpio
gpu
hid
hsi
hv
hwmon
hwspinlock
hwtracing
i2c
ide
idle
iio
infiniband
input
iommu
ipack
irqchip
isdn
leds
lightnvm
macintosh
mailbox
mcb
md
media media: dvbdev: add a mutex protecting the "mdev" pointer 2018-05-11 12:09:59 -04:00
memory
memstick
message
mfd
misc
mmc
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
sn
soc
soundwire
spi
spmi
ssb
staging
target
tc
tee
thermal
thunderbolt
tty
uio
usb
uwb
vfio
vhost
video
virt
virtio
visorbus
vlynq
vme
w1
watchdog
xen
zorro
Kconfig
Makefile