linux-stable.git/arch, branch linux-3.11.y

exec/ptrace: fix get_dumpable() incorrect tests

2013-11-29T18:42:17+00:00

commit d049f74f2dbe71354d43d393ac3a188947811348 upstream.

The get_dumpable() return value is not boolean.  Most users of the
function actually want to be testing for non-SUID_DUMP_USER(1) rather than
SUID_DUMP_DISABLE(0).  The SUID_DUMP_ROOT(2) is also considered a
protected state.  Almost all places did this correctly, excepting the two
places fixed in this patch.

Wrong logic:
    if (dumpable == SUID_DUMP_DISABLE) { /* be protective */ }
        or
    if (dumpable == 0) { /* be protective */ }
        or
    if (!dumpable) { /* be protective */ }

Correct logic:
    if (dumpable != SUID_DUMP_USER) { /* be protective */ }
        or
    if (dumpable != 1) { /* be protective */ }

Without this patch, if the system had set the sysctl fs/suid_dumpable=2, a
user was able to ptrace attach to processes that had dropped privileges to
that user.  (This may have been partially mitigated if Yama was enabled.)

The macros have been moved into the file that declares get/set_dumpable(),
which means things like the ia64 code can see them too.

CVE-2013-2929

Reported-by: Vasily Kulikov 
Signed-off-by: Kees Cook 
Cc: "Luck, Tony" 
Cc: Oleg Nesterov 
Cc: "Eric W. Biederman" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

sched, idle: Fix the idle polling state logic

2013-11-29T18:42:15+00:00

commit ea8117478918a4734586d35ff530721b682425be upstream.

Mike reported that commit 7d1a9417 ("x86: Use generic idle loop")
regressed several workloads and caused excessive reschedule
interrupts.

The patch in question failed to notice that the x86 code had an
inverted sense of the polling state versus the new generic code (x86:
default polling, generic: default !polling).

Fix the two prominent x86 mwait based idle drivers and introduce a few
new generic polling helpers (fixing the wrong smp_mb__after_clear_bit
usage).

Also switch the idle routines to using tif_need_resched() which is an
immediate TIF_NEED_RESCHED test as opposed to need_resched which will
end up being slightly different.

Reported-by: Mike Galbraith 
Signed-off-by: Peter Zijlstra 
Cc: lenb@kernel.org
Cc: tglx@linutronix.de
Link: http://lkml.kernel.org/n/tip-nc03imb0etuefmzybzj7sprf@git.kernel.org
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

crypto: s390 - Fix aes-cbc IV corruption

2013-11-29T18:42:15+00:00

commit f262f0f5cad0c9eca61d1d383e3b67b57dcbe5ea upstream.

The cbc-aes-s390 algorithm incorrectly places the IV in the tfm
data structure.  As the tfm is shared between multiple threads,
this introduces a possibility of data corruption.

This patch fixes this by moving the parameter block containing
the IV and key onto the stack (the block is 48 bytes long).

The same bug exists elsewhere in the s390 crypto system and they
will be fixed in subsequent patches.

Signed-off-by: Herbert Xu 
Signed-off-by: Greg Kroah-Hartman

xtensa: don't use alternate signal stack on threads

2013-11-13T03:08:10+00:00

commit cba9a90053e3b7973eff4f1946f33032e98eeed5 upstream.

According to create_thread(3): "The new thread does not inherit the creating
thread's alternate signal stack". Since commit f9a3879a (Fix sigaltstack
corruption among cloned threads), current->sas_ss_size is set to 0 for cloned
processes sharing VM with their parent. Don't use the (nonexistent) alternate
signal stack in this case. This has been broken since commit 29c4dfd9 ([XTENSA]
Remove non-rt signal handling).

Fixes the SA_ONSTACK part of the nptl/tst-cancel20 test from uClibc.

Signed-off-by: Baruch Siach 
Signed-off-by: Max Filippov 
Signed-off-by: Chris Zankel 
Signed-off-by: Greg Kroah-Hartman

uml: check length in exitcode_proc_write()

2013-11-13T03:08:10+00:00

commit 201f99f170df14ba52ea4c52847779042b7a623b upstream.

We don't cap the size of buffer from the user so we could write past the
end of the array here.  Only root can write to this file.

Reported-by: Nico Golde 
Reported-by: Fabian Yamaguchi 
Signed-off-by: Dan Carpenter 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ARC: Incorrect mm reference used in vmalloc fault handler

2013-11-13T03:08:09+00:00

commit 9c41f4eeb9d51f3ece20428d35a3ea32cf3b5622 upstream.

A vmalloc fault needs to sync up PGD/PTE entry from init_mm to current
task's "active_mm".  ARC vmalloc fault handler however was using mm.

A vmalloc fault for non user task context (actually pre-userland, from
init thread's open for /dev/console) caused the handler to deref NULL mm
(for mm->pgd)

The reasons it worked so far is amazing:

1. By default (!SMP), vmalloc fault handler uses a cached value of PGD.
   In SMP that MMU register is repurposed hence need for mm pointer deref.

2. In pre-3.12 SMP kernel, the problem triggering vmalloc didn't exist in
   pre-userland code path - it was introduced with commit 20bafb3d23d108bc
   "n_tty: Move buffers into n_tty_data"

Signed-off-by: Vineet Gupta 
Cc: Gilad Ben-Yossef 
Cc: Noam Camus 
Cc: Peter Hurley 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

parisc: Do not crash 64bit SMP kernels on machines with >= 4GB RAM

2013-11-13T03:08:09+00:00

commit 54e181e073fc1415e41917d725ebdbd7de956455 upstream.

Since the beginning of the parisc-linux port, sometimes 64bit SMP kernels were
not able to bring up other CPUs than the monarch CPU and instead crashed the
kernel.  The reason was unclear, esp. since it involved various machines (e.g.
J5600, J6750 and SuperDome). Testing showed, that those crashes didn't happened
when less than 4GB were installed, or if a 32bit Linux kernel was booted.

In the end, the fix for those SMP problems is trivial:
During the early phase of the initialization of the CPUs, including the monarch
CPU, the PDC_PSW firmware function to enable WIDE (=64bit) mode is called.
It's documented that this firmware function may clobber various registers, and
one one of those possibly clobbered registers is %cr30 which holds the task
thread info pointer.

Now, if %cr30 would always have been clobbered, then this bug would have been
detected much earlier. But lots of testing finally showed, that - at least for
%cr30 - on some machines only the upper 32bits of the 64bit register suddenly
turned zero after the firmware call.

So, after finding the root cause, the explanation for the various crashes
became clear:
- On 32bit SMP Linux kernels all upper 32bit were zero, so we didn't faced this
  problem.
- Monarch CPUs in 64bit mode always booted sucessfully, because the inital task
  thread info pointer was below 4GB.
- Secondary CPUs booted sucessfully on machines with less than 4GB RAM because
  the upper 32bit were zero anyay.
- Secondary CPus failed to boot if we had more than 4GB RAM and the task thread
  info pointer was located above the 4GB boundary.

Finally, the patch to fix this problem is trivial by saving the %cr30 register
before the firmware call and restoring it afterwards.

Signed-off-by: Helge Deller 
Signed-off-by: John David Anglin 
Signed-off-by: Helge Deller 
Signed-off-by: Greg Kroah-Hartman

x86: Update UV3 hub revision ID

2013-11-13T03:08:06+00:00

commit dd3c9c4b603c664fedc12facf180db0f1794aafe upstream.

The UV3 hub revision ID is different than expected.  The first
revision was supposed to start at 1 but instead will start at 0.

Signed-off-by: Russ Anderson 
Link: http://lkml.kernel.org/r/20131014161733.GA6274@sgi.com
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

ARM: integrator: deactivate timer0 on the Integrator/CP

2013-11-04T12:35:19+00:00

commit 29114fd7db2fc82a34da8340d29b8fa413e03dca upstream.

This fixes a long-standing Integrator/CP regression from
commit 870e2928cf3368ca9b06bc925d0027b0a56bcd8e
"ARM: integrator-cp: convert use CLKSRC_OF for timer init"

When this code was introduced, the both aliases pointing the
system to use timer1 as primary (clocksource) and timer2
as secondary (clockevent) was ignored, and the system would
simply use the first two timers found as clocksource and
clockevent.

However this made the system timeline accelerate by a
factor x25, as it turns out that the way the clocking
actually works (totally undocumented and found after some
trial-and-error) is that timer0 runs @ 25MHz and timer1
and timer2 runs @ 1MHz. Presumably this divider setting
is a boot-on default and configurable albeit the way to
configure it is not documented.

So as a quick fix to the problem, let's mark timer0 as
disabled, so the code will chose timer1 and timer2 as it
used to.

This also deletes the two aliases for the primary and
secondary timer as they have been superceded by the
auto-selection

Cc: Rob Herring 
Cc: Russell King 
Signed-off-by: Linus Walleij 
Signed-off-by: Olof Johansson 
Signed-off-by: Greg Kroah-Hartman

ARM: 7851/1: check for number of arguments in syscall_get/set_arguments()

2013-11-04T12:35:18+00:00

commit 3c1532df5c1b54b5f6246cdef94eeb73a39fe43a upstream.

In ftrace_syscall_enter(),
    syscall_get_arguments(..., 0, n, ...)
        if (i == 0) {  ...; n--;}
        memcpy(..., n * sizeof(args[0]));
If 'number of arguments(n)' is zero and 'argument index(i)' is also zero in
syscall_get_arguments(), none of arguments should be copied by memcpy().
Otherwise 'n--' can be a big positive number and unexpected amount of data
will be copied. Tracing system calls which take no argument, say sync(void),
may hit this case and eventually make the system corrupted.
This patch fixes the issue both in syscall_get_arguments() and
syscall_set_arguments().

Acked-by: Will Deacon 
Signed-off-by: AKASHI Takahiro 
Signed-off-by: Will Deacon 
Signed-off-by: Russell King 
Signed-off-by: Greg Kroah-Hartman