Jiri Kosina 10b3a32d29 random: fix accounting race condition with lockless irq entropy_count update ... Commit 902c098a36 ("random: use lockless techniques in the interrupt path") turned IRQ path from being spinlock protected into lockless cmpxchg-retry update. That commit removed r->lock serialization between crediting entropy bits from IRQ context and accounting when extracting entropy on userspace read path, but didn't turn the r->entropy_count reads/updates in account() to use cmpxchg as well. It has been observed, that under certain circumstances this leads to read() on /dev/urandom to return 0 (EOF), as r->entropy_count gets corrupted and becomes negative, which in turn results in propagating 0 all the way from account() to the actual read() call. Convert the accounting code to be the proper lockless counterpart of what has been partially done by 902c098a36. Signed-off-by: Jiri Kosina <jkosina@suse.cz> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Greg KH <greg@kroah.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2013-05-24 16:22:52 -07:00
..
agp	drm/i915: Disable WC PTE updates to w/a buggy IOMMU on ILK	2013-02-20 00:21:49 +01:00
hw_random	drivers/char/hw_random: don't check resource with devm_ioremap_resource	2013-05-12 15:19:46 +02:00
ipmi	ipmi: ipmi_devintf: compat_ioctl method fails to take ipmi_mutex	2013-05-16 13:49:25 -07:00
mwave	8250: three way resolve of the 8250 diffs	2012-07-17 09:11:50 -07:00
pcmcia	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2013-02-26 20:16:07 -08:00
tpm	TPM: Retry SaveState command in suspend path	2013-04-17 09:31:32 -05:00
xilinx_hwicap	char: remove use of __devexit	2012-11-21 12:55:19 -08:00
apm-emulation.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/apm	2012-04-05 17:34:30 -07:00
applicom.c	applicom: use correct array offset	2013-03-15 12:23:48 -07:00
applicom.h
bfin-otp.c	llseek: automatically add .llseek fop	2010-10-15 15:53:27 +02:00
bsr.c	powerpc/BSR: cleanup the error path of bsr_init	2012-07-17 10:27:38 -07:00
ds1302.c	Remove all #inclusions of asm/system.h	2012-03-28 18:30:03 +01:00
ds1620.c	ds1620: single_open() leak	2013-05-05 00:11:29 -04:00
dsp56k.c	new helper: file_inode(file)	2013-02-22 23:31:31 -05:00
dtlk.c	new helper: file_inode(file)	2013-02-22 23:31:31 -05:00
efirtc.c	rtc: single_open() leaks	2013-05-05 00:12:29 -04:00
generic_nvram.c	drivers: fix up various ->llseek() implementations	2011-07-20 20:47:58 -04:00
genrtc.c	rtc: single_open() leaks	2013-05-05 00:12:29 -04:00
hangcheck-timer.c
hpet.c	vm: convert HPET mmap to vm_iomap_memory() helper	2013-04-19 09:46:39 -07:00
i8k.c	module_param: make bool parameters really bool (drivers & misc)	2012-01-13 09:32:20 +10:30
Kconfig	tty: Added a CONFIG_TTY option to allow removal of TTY	2013-01-18 16:15:27 -08:00
lp.c	Char: lp, protect LPGETSTATUS with port_mutex	2013-05-16 18:08:58 -07:00
Makefile	IPMI: Change link order	2012-10-16 18:07:12 -07:00
mbcs.c	char: remove use of __devinitconst	2012-11-21 12:55:19 -08:00
mbcs.h	Fix common misspellings	2011-03-31 11:26:23 -03:00
mem.c	aio: don't include aio.h in sched.h	2013-05-07 20:16:25 -07:00
misc.c	drivers/char/misc.c:misc_register(): do not loop on misc_list unconditionally	2013-02-27 19:10:21 -08:00
mmtimer.c	drivers/char/mmtimer.c: Remove useless kfree	2012-09-26 13:20:40 -07:00
msm_smd_pkt.c	drivers/char/msm_smd_pkt.c: don't use IS_ERR()	2011-08-25 16:25:33 -07:00
mspec.c	mm: kill vma flag VM_RESERVED and mm->reserved_vm counter	2012-10-09 16:22:19 +09:00
nsc_gpio.c	new helper: file_inode(file)	2013-02-22 23:31:31 -05:00
nvram.c	Remove all #inclusions of asm/system.h	2012-03-28 18:30:03 +01:00
nwbutton.c	drivers/char: removes unnecessary semicolon	2012-09-26 13:20:39 -07:00
nwbutton.h
nwflash.c	Merge branch 'late/fixes' into fixes	2012-10-07 07:22:32 -07:00
pc8736x_gpio.c	pc8736x_gpio: use platform_device_unregister in pc8736x_gpio_cleanup()	2012-10-24 15:52:29 -07:00
ppdev.c	new helper: file_inode(file)	2013-02-22 23:31:31 -05:00
ps3flash.c	new helper: file_inode(file)	2013-02-22 23:31:31 -05:00
random.c	random: fix accounting race condition with lockless irq entropy_count update	2013-05-24 16:22:52 -07:00
raw.c	new helper: file_inode(file)	2013-02-22 23:31:31 -05:00
rtc.c	drivers/char: removes unnecessary semicolon	2012-09-26 13:20:39 -07:00
scx200_gpio.c	llseek: automatically add .llseek fop	2010-10-15 15:53:27 +02:00
snsc_event.c
snsc.c	Merge branch 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl	2010-10-22 10:52:56 -07:00
snsc.h	headers: kobject.h redux	2011-01-10 08:51:44 -08:00
sonypi.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2013-02-26 20:16:07 -08:00
tb0219.c	new helper: file_inode(file)	2013-02-22 23:31:31 -05:00
tile-srom.c	drivers: char: Use PTR_RET function	2013-03-25 13:18:11 -07:00
tlclk.c	drivers/char/tlclk.c: fix error return code	2012-08-16 10:09:15 -07:00
toshiba.c	Merge branch 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl	2010-10-22 10:52:56 -07:00
ttyprintk.c	ttyprintk: Fix NULL pointer deref by setting tty_port ops after initializing port	2013-05-21 10:13:23 -07:00
uv_mmtimer.c	BKL: remove extraneous #include <smp_lock.h>	2010-11-17 08:59:32 -08:00
virtio_console.c	Lots of virtio work which wasn't quite ready for last merge window. Plus	2013-05-02 14:14:04 -07:00