linux-stable.git/arch, branch v3.4.97

ptrace,x86: force IRET path after a ptrace_stop()

2014-07-07T01:49:20+00:00

commit b9cd18de4db3c9ffa7e17b0dc0ca99ed5aa4d43a upstream.

The 'sysret' fastpath does not correctly restore even all regular
registers, much less any segment registers or reflags values.  That is
very much part of why it's faster than 'iret'.

Normally that isn't a problem, because the normal ptrace() interface
catches the process using the signal handler infrastructure, which
always returns with an iret.

However, some paths can get caught using ptrace_event() instead of the
signal path, and for those we need to make sure that we aren't going to
return to user space using 'sysret'.  Otherwise the modifications that
may have been done to the register set by the tracer wouldn't
necessarily take effect.

Fix it by forcing IRET path by setting TIF_NOTIFY_RESUME from
arch_ptrace_stop_needed() which is invoked from ptrace_stop().

Signed-off-by: Tejun Heo 
Reported-by: Andy Lutomirski 
Acked-by: Oleg Nesterov 
Suggested-by: Linus Torvalds 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

powerpc: fix typo 'CONFIG_PPC_CPU'

2014-07-07T01:49:20+00:00

commit b69a1da94f3d1589d1942b5d1b384d8cfaac4500 upstream.

Commit cd64d1697cf0 ("powerpc: mtmsrd not defined") added a check for
CONFIG_PPC_CPU were a check for CONFIG_PPC_FPU was clearly intended.

Fixes: cd64d1697cf0 ("powerpc: mtmsrd not defined")
Signed-off-by: Paul Bolle 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc: fix typo 'CONFIG_PMAC'

2014-07-07T01:49:20+00:00

commit 6e0fdf9af216887e0032c19d276889aad41cad00 upstream.

Commit b0d278b7d3ae ("powerpc/perf_event: Reduce latency of calling
perf_event_do_pending") added a check for CONFIG_PMAC were a check for
CONFIG_PPC_PMAC was clearly intended.

Fixes: b0d278b7d3ae ("powerpc/perf_event: Reduce latency of calling perf_event_do_pending")
Signed-off-by: Paul Bolle 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc/pseries: Fix overwritten PE state

2014-07-07T01:49:20+00:00

commit 54f112a3837d4e7532bbedbbbf27c0de277be510 upstream.

In pseries_eeh_get_state(), EEH_STATE_UNAVAILABLE is always
overwritten by EEH_STATE_NOT_SUPPORT because of the missed
"break" there. The patch fixes the issue.

Reported-by: Joe Perches 
Signed-off-by: Gavin Shan 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

MIPS: MSC: Prevent out-of-bounds writes to MIPS SC ioremap'd region

2014-07-07T01:49:19+00:00

commit ab6c15bc6620ebe220970cc040b29bcb2757f373 upstream.

Previously, the lower limit for the MIPS SC initialization loop was
set incorrectly allowing one extra loop leading to writes
beyond the MSC ioremap'd space. More precisely, the value of the 'imp'
in the last loop increased beyond the msc_irqmap_t boundaries and
as a result of which, the 'n' variable was loaded with an incorrect
value. This value was used later on to calculate the offset in the
MSC01_IC_SUP which led to random crashes like the following one:

CPU 0 Unable to handle kernel paging request at virtual address e75c0200,
epc == 8058dba4, ra == 8058db90
[...]
Call Trace:
[<8058dba4>] init_msc_irqs+0x104/0x154
[<8058b5bc>] arch_init_irq+0xd8/0x154
[<805897b0>] start_kernel+0x220/0x36c

Kernel panic - not syncing: Attempted to kill the idle task!

This patch fixes the problem

Signed-off-by: Markos Chandras 
Reviewed-by: James Hogan 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7118/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

x86_32, entry: Do syscall exit work on badsys (CVE-2014-4508)

2014-07-01T03:01:34+00:00

commit 554086d85e71f30abe46fc014fea31929a7c6a8a upstream.

The bad syscall nr paths are their own incomprehensible route
through the entry control flow.  Rearrange them to work just like
syscalls that return -ENOSYS.

This fixes an OOPS in the audit code when fast-path auditing is
enabled and sysenter gets a bad syscall nr (CVE-2014-4508).

This has probably been broken since Linux 2.6.27:
af0575bba0 i386 syscall audit fast-path

Cc: Roland McGrath 
Reported-by: Toralf Förster 
Signed-off-by: Andy Lutomirski 
Link: http://lkml.kernel.org/r/e09c499eade6fc321266dd6b54da7beb28d6991c.1403558229.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin 
Signed-off-by: Greg Kroah-Hartman

x86, x32: Use compat shims for io_{setup,submit}

2014-07-01T03:01:33+00:00

commit 7fd44dacdd803c0bbf38bf478d51d280902bb0f1 upstream.

The io_setup takes a pointer to a context id of type aio_context_t.
This in turn is typed to a __kernel_ulong_t.  We could tweak the
exported headers to define this as a 64bit quantity for specific
ABIs, but since we already have a 32bit compat shim for the x86 ABI,
let's just re-use that logic.  The libaio package is also written to
expect this as a pointer type, so a compat shim would simplify that.

The io_submit func operates on an array of pointers to iocb structs.
Padding out the array to be 64bit aligned is a huge pain, so convert
it over to the existing compat shim too.

We don't convert io_getevents to the compat func as its only purpose
is to handle the timespec struct, and the x32 ABI uses 64bit times.

With this change, the libaio package can now pass its testsuite when
built for the x32 ABI.

Signed-off-by: Mike Frysinger 
Link: http://lkml.kernel.org/r/1399250595-5005-1-git-send-email-vapier@gentoo.org
Cc: H.J. Lu 
Signed-off-by: H. Peter Anvin 
Signed-off-by: Greg Kroah-Hartman

x86-32, espfix: Remove filter for espfix32 due to race

2014-07-01T03:01:33+00:00

commit 246f2d2ee1d715e1077fc47d61c394569c8ee692 upstream.

It is not safe to use LAR to filter when to go down the espfix path,
because the LDT is per-process (rather than per-thread) and another
thread might change the descriptors behind our back.  Fortunately it
is always *safe* (if a bit slow) to go down the espfix path, and a
32-bit LDT stack segment is extremely rare.

Signed-off-by: H. Peter Anvin 
Link: http://lkml.kernel.org/r/1398816946-3351-1-git-send-email-hpa@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

ARM: stacktrace: avoid listing stacktrace functions in stacktrace

2014-07-01T03:01:33+00:00

commit 3683f44c42e991d313dc301504ee0fca1aeb8580 upstream.

While debugging the FEC ethernet driver using stacktrace, it was noticed
that the stacktraces always begin as follows:

 [] save_stack_trace_tsk+0x0/0x98
 [] save_stack_trace+0x24/0x28
 ...

This is because the stack trace code includes the stack frames for itself.
This is incorrect behaviour, and also leads to "skip" doing the wrong
thing (which is the number of stack frames to avoid recording.)

Perversely, it does the right thing when passed a non-current thread.  Fix
this by ensuring that we have a known constant number of frames above the
main stack trace function, and always skip these.

Signed-off-by: Russell King 
Signed-off-by: Greg Kroah-Hartman

s390/lowcore: reserve 96 bytes for IRB in lowcore

2014-07-01T03:01:31+00:00

commit 993072ee67aa179c48c85eb19869804e68887d86 upstream.

The IRB might be 96 bytes if the extended-I/O-measurement facility is
used. This feature is currently not used by Linux, but struct irb
already has the emw defined. So let's make the irb in lowcore match the
size of the internal data structure to be future proof.
We also have to add a pad, to correctly align the paste.

The bigger irb field also circumvents a bug in some QEMU versions that
always write the emw field on test subchannel and therefore destroy the
paste definitions of this CPU. Running under these QEMU version broke
some timing functions in the VDSO and all users of these functions,
e.g. some JREs.

Signed-off-by: Christian Borntraeger 
Signed-off-by: Martin Schwidefsky 
Cc: Heiko Carstens 
Cc: Sebastian Ott 
Cc: Cornelia Huck 
Signed-off-by: Greg Kroah-Hartman