linux/drivers/char/random.c, branch v3.12.10

Merge tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random

2013-10-10T19:31:43Z

Pull /dev/random changes from Ted Ts'o: "These patches are designed to enable improvements to /dev/random for non-x86 platforms, in particular MIPS and ARM" * tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random: random: allow architectures to optionally define random_get_entropy() random: run random_int_secret_init() run after all late_initcalls

random: allow architectures to optionally define random_get_entropy()

2013-10-10T18:30:53Z

Allow architectures which have a disabled get_cycles() function to provide a random_get_entropy() function which provides a fine-grained, rapidly changing counter that can be used by the /dev/random driver. For example, an architecture might have a rapidly changing register used to control random TLB cache eviction, or DRAM refresh that doesn't meet the requirements of get_cycles(), but which is good enough for the needs of the random driver. Signed-off-by: "Theodore Ts'o" Cc: stable@vger.kernel.org

random: run random_int_secret_init() run after all late_initcalls

2013-09-23T10:35:06Z

The some platforms (e.g., ARM) initializes their clocks as late_initcalls for some unknown reason. So make sure random_int_secret_init() is run after all of the late_initcalls are run. Cc: stable@vger.kernel.org Signed-off-by: "Theodore Ts'o"

Remove GENERIC_HARDIRQ config option

2013-09-13T13:09:52Z

After the last architecture switched to generic hard irqs the config options HAVE_GENERIC_HARDIRQS & GENERIC_HARDIRQS and the related code for !CONFIG_GENERIC_HARDIRQS can be removed. Signed-off-by: Martin Schwidefsky

char: Convert use of typedef ctl_table to struct ctl_table

2013-06-17T23:43:08Z

This typedef is unnecessary and should just be removed. Signed-off-by: Joe Perches Signed-off-by: Greg Kroah-Hartman

random: fix accounting race condition with lockless irq entropy_count update

2013-05-24T23:22:52Z

Commit 902c098a3663 ("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 902c098a3663. Signed-off-by: Jiri Kosina Cc: Theodore Ts'o Cc: Greg KH Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

drivers/char/random.c: fix priming of last_data

2013-05-24T23:22:52Z

Commit ec8f02da9ea5 ("random: prime last_data value per fips requirements") added priming of last_data per fips requirements. Unfortuantely, it did so in a way that can lead to multiple threads all incrementing nbytes, but only one actually doing anything with the extra data, which leads to some fun random corruption and panics. The fix is to simply do everything needed to prime last_data in a single shot, so there's no window for multiple cpus to increment nbytes -- in fact, we won't even increment or decrement nbytes anymore, we'll just extract the needed EXTRACT_SIZE one time per pool and then carry on with the normal routine. All these changes have been tested across multiple hosts and architectures where panics were previously encoutered. The code changes are are strictly limited to areas only touched when when booted in fips mode. This change should also go into 3.8-stable, to make the myriads of fips users on 3.8.x happy. Signed-off-by: Jarod Wilson Tested-by: Jan Stancek Tested-by: Jan Stodola Cc: Herbert Xu Acked-by: Neil Horman Cc: "David S. Miller" Cc: Matt Mackall Cc: "Theodore Ts'o" Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/string_helpers: introduce generic string_unescape

2013-05-01T00:04:03Z

There are several places in kernel where modules unescapes input to convert C-Style Escape Sequences into byte codes. The patch provides generic implementation of such approach. Test cases are also included into the patch. [akpm@linux-foundation.org: clarify comment] [akpm@linux-foundation.org: export get_random_int() to modules] Signed-off-by: Andy Shevchenko Cc: Samuel Thibault Cc: Greg Kroah-Hartman Cc: Jason Baron Cc: Alexander Viro Cc: William Hubbs Cc: Chris Brannon Cc: Kirk Reiser Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random

2013-03-08T22:42:16Z

Pull random fixes from Ted Ts'o: "Fix a circular locking dependency in random's collection of cputime used by a thread when it exits." * tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random: random: fix locking dependency with the tasklist_lock

random: fix locking dependency with the tasklist_lock

2013-03-04T17:05:15Z

Commit 6133705494bb introduced a circular lock dependency because posix_cpu_timers_exit() is called by release_task(), which is holding a writer lock on tasklist_lock, and this can cause a deadlock since kill_fasync() gets called with nonblocking_pool.lock taken. There's no reason why kill_fasync() needs to be taken while the random pool is locked, so move it out to fix this locking dependency. Signed-off-by: "Theodore Ts'o" Reported-by: Russ Dill Cc: stable@kernel.org