aha/drivers
Mikulas Patocka 61578dcd3f dm snapshot: fix header corruption race on invalidation
If a persistent snapshot fills up, a race can corrupt the on-disk header
which causes a crash on any future attempt to activate the snapshot
(typically while booting).  This patch fixes the race.

When the snapshot overflows, __invalidate_snapshot is called, which calls
snapshot store method drop_snapshot. It goes to persistent_drop_snapshot that
calls write_header. write_header constructs the new header in the "area"
location.

Concurrently, an existing kcopyd job may finish, call copy_callback
and commit_exception method, that goes to persistent_commit_exception.
persistent_commit_exception doesn't do locking, relying on the fact that
callbacks are single-threaded, but it can race with snapshot invalidation and
overwrite the header that is just being written while the snapshot is being
invalidated.

The result of this race is a corrupted header being written that can
lead to a crash on further reactivation (if chunk_size is zero in the
corrupted header).

The fix is to use separate memory areas for each.

See the bug: https://bugzilla.redhat.com/show_bug.cgi?id=461506

Cc: stable@kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-09-04 20:40:39 +01:00
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accessibility
acpi ACPI: don't free non-existent backlight in acpi video module 2009-08-28 15:17:07 -04:00
amba
ata ata_piix: parallel scanning on PATA needs an extra locking 2009-08-31 17:25:00 -10:00
atm
auxdisplay
base PM / Driver Core: Kill dev_pm_ops platform warning for now 2009-08-10 23:41:18 +02:00
block
bluetooth
cdrom
char tty: make sure to flush any pending work when halting the ldisc 2009-08-25 09:12:43 -07:00
clocksource sh: CMT suspend/resume 2009-08-15 12:58:45 +09:00
connector
cpufreq [CPUFREQ] Make cpufreq suspend code conditional on powerpc. 2009-08-04 14:32:11 -04:00
cpuidle
crypto
dca
dio
dma Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx 2009-07-30 16:46:31 -07:00
edac amd64_edac: print debug statements only on error 2009-08-04 12:10:06 +02:00
eisa
firewire
firmware
gpio
gpu Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel 2009-08-31 17:22:10 -10:00
hid
hwmon
i2c i2c-stu300: I2C STU300 stability updates 2009-08-20 22:27:58 +01:00
ide
idle
ieee1394
ieee802154
infiniband
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2009-08-24 12:25:27 -07:00
isdn Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2009-08-04 15:38:34 -07:00
leds leds: after setting inverted attribute, we must update the LED 2009-08-26 20:06:53 -07:00
lguest lguest and virtio: cleanup struct definitions to Linux style. 2009-07-30 16:03:46 +09:30
macintosh m68k: count can reach 51, not 50 2009-08-26 23:14:49 +02:00
mca
md dm snapshot: fix header corruption race on invalidation 2009-09-04 20:40:39 +01:00
media V4L/DVB (12502): gspca - sn9c20x: Fix gscpa sn9c20x build errors. 2009-08-31 02:24:54 -03:00
memstick
message
mfd mfd: twl4030 irq fixes 2009-08-04 20:31:32 +02:00
misc cb710: use SG_MITER_TO_SG/SG_MITER_FROM_SG 2009-07-31 12:28:46 +02:00
mmc drivers/mmc: correct error-handling code 2009-08-07 10:39:56 -07:00
mtd [ARM] Orion NAND: Make asm volatile avoid GCC pushing ldrd out of the loop 2009-08-24 11:56:00 -04:00
net virtio: net refill on out-of-memory 2009-08-26 12:22:32 -07:00
nubus
of
oprofile
parisc parisc: hppb.c - fix printk format strings 2009-08-02 15:42:39 +02:00
parport
pci PCI: check saved state before restore 2009-08-20 09:08:45 -07:00
pcmcia
platform toshiba_acpi: return on a fail path 2009-08-28 15:17:07 -04:00
pnp
power Merge git://git.infradead.org/users/cbou/battery-2.6.31 2009-07-30 16:45:53 -07:00
pps pps: fix incorrect verdict check 2009-08-26 20:06:52 -07:00
ps3
rapidio
regulator
rtc rtc: mark if rtc-cmos drivers were successfully registered 2009-07-29 19:10:35 -07:00
s390 [S390] drivers/s390: put NULL test before dereference 2009-08-23 18:10:00 +02:00
sbus
scsi [SCSI] mpt2sas: fix config request and diag reset deadlock 2009-08-14 09:16:05 -05:00
serial ARM: S3C64XX: serial: Fix a typo in Kconfig 2009-08-14 00:43:46 +01:00
sh
sn
spi spi_s3c24xx: fix transfer setup code 2009-08-18 16:31:13 -07:00
ssb
staging Staging: rspiusb: Fix buffer overflow 2009-08-07 16:12:03 -07:00
tc
telephony
thermal thermal_sys: check get_temp return value 2009-08-26 20:06:52 -07:00
uio
usb USB: fix oops on disconnect in cdc-acm 2009-08-07 16:05:14 -07:00
uwb
video xenfb: connect to backend before registering fb 2009-08-27 12:31:18 -07:00
virtio virtio: refactor find_vqs 2009-07-30 16:03:45 +09:30
vlynq
w1 drivers/w1/masters/omap_hdq.c: fix missing mutex unlock 2009-08-07 10:39:55 -07:00
watchdog [WATCHDOG] ar7_wdt: fix path to ar7-specific headers 2009-08-15 13:05:01 +00:00
xen
zorro
Kconfig
Makefile