linux-toradex.git, branch v3.4.67

Linux 3.4.67

2013-10-22T08:19:41+00:00

mm: do not grow the stack vma just because of an overrun on preceding vma

2013-10-22T08:02:25+00:00

commit 09884964335e85e897876d17783c2ad33cf8a2e0 upstream.

The stack vma is designed to grow automatically (marked with VM_GROWSUP
or VM_GROWSDOWN depending on architecture) when an access is made beyond
the existing boundary.  However, particularly if you have not limited
your stack at all ("ulimit -s unlimited"), this can cause the stack to
grow even if the access was really just one past *another* segment.

And that's wrong, especially since we first grow the segment, but then
immediately later enforce the stack guard page on the last page of the
segment.  So _despite_ first growing the stack segment as a result of
the access, the kernel will then make the access cause a SIGSEGV anyway!

So do the same logic as the guard page check does, and consider an
access to within one page of the next segment to be a bad access, rather
than growing the stack to abut the next segment.

Reported-and-tested-by: Heiko Carstens 
Signed-off-by: Linus Torvalds 
Cc: Xishi Qiu 
Signed-off-by: Greg Kroah-Hartman

mm/mmap: check for RLIMIT_AS before unmapping

2013-10-22T08:02:25+00:00

commit e8420a8ece80b3fe810415ecf061d54ca7fab266 upstream.

Fix a corner case for MAP_FIXED when requested mapping length is larger
than rlimit for virtual memory.  In such case any overlapping mappings
are unmapped before we check for the limit and return ENOMEM.

The check is moved before the loop that unmaps overlapping parts of
existing mappings.  When we are about to hit the limit (currently mapped
pages + len > limit) we scan for overlapping pages and check again
accounting for them.

This fixes situation when userspace program expects that the previous
mappings are preserved after the mmap() syscall has returned with error.
(POSIX clearly states that successfull mapping shall replace any
previous mappings.)

This corner case was found and can be tested with LTP testcase:

testcases/open_posix_testsuite/conformance/interfaces/mmap/24-2.c

In this case the mmap, which is clearly over current limit, unmaps
dynamic libraries and the testcase segfaults right after returning into
userspace.

I've also looked at the second instance of the unmapping loop in the
do_brk().  The do_brk() is called from brk() syscall and from vm_brk().
The brk() syscall checks for overlapping mappings and bails out when
there are any (so it can't be triggered from the brk syscall).  The
vm_brk() is called only from binmft handlers so it shouldn't be
triggered unless binmft handler created overlapping mappings.

Signed-off-by: Cyril Hrubis 
Reviewed-by: Mel Gorman 
Reviewed-by: Wanpeng Li 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Cc: Xishi Qiu 
Signed-off-by: Greg Kroah-Hartman

drm/radeon: fix hw contexts for SUMO2 asics

2013-10-22T08:02:25+00:00

commit 50b8f5aec04ebec7dbdf2adb17220b9148c99e63 upstream.

They have 4 rather than 8.

Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=63599

Signed-off-by: wojciech kapuscinski 
Signed-off-by: Alex Deucher 
Signed-off-by: Greg Kroah-Hartman

watchdog: ts72xx_wdt: locking bug in ioctl

2013-10-22T08:02:25+00:00

commit 8612ed0d97abcf1c016d34755b7cf2060de71963 upstream.

Calling the WDIOC_GETSTATUS & WDIOC_GETBOOTSTATUS and twice will cause a
interruptible deadlock.

Signed-off-by: Dan Carpenter 
Reviewed-by: Guenter Roeck 
Signed-off-by: Wim Van Sebroeck 
Cc: Jonghwan Choi 
Signed-off-by: Greg Kroah-Hartman

parisc: fix interruption handler to respect pagefault_disable()

2013-10-22T08:02:25+00:00

commit 59b33f148cc08fb33cbe823fca1e34f7f023765e upstream.

Running an "echo t > /proc/sysrq-trigger" crashes the parisc kernel.  The
problem is, that in print_worker_info() we try to read the workqueue info via
the probe_kernel_read() functions which use pagefault_disable() to avoid
crashes like this:
    probe_kernel_read(&pwq, &worker->current_pwq, sizeof(pwq));
    probe_kernel_read(&wq, &pwq->wq, sizeof(wq));
    probe_kernel_read(name, wq->name, sizeof(name) - 1);

The problem here is, that the first probe_kernel_read(&pwq) might return zero
in pwq and as such the following probe_kernel_reads() try to access contents of
the page zero which is read protected and generate a kernel segfault.

With this patch we fix the interruption handler to call parisc_terminate()
directly only if pagefault_disable() was not called (in which case
preempt_count()==0).  Otherwise we hand over to the pagefault handler which
will try to look up the faulting address in the fixup tables.

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

KVM: PPC: Book3S HV: Fix typo in saving DSCR

2013-10-22T08:02:25+00:00

commit cfc860253abd73e1681696c08ea268d33285a2c4 upstream.

This fixes a typo in the code that saves the guest DSCR (Data Stream
Control Register) into the kvm_vcpu_arch struct on guest exit.  The
effect of the typo was that the DSCR value was saved in the wrong place,
so changes to the DSCR by the guest didn't persist across guest exit
and entry, and some host kernel memory got corrupted.

Signed-off-by: Paul Mackerras 
Acked-by: Alexander Graf 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

ext4: fix memory leak in xattr

2013-10-22T08:02:25+00:00

commit 6e4ea8e33b2057b85d75175dd89b93f5e26de3bc upstream.

If we take the 2nd retry path in ext4_expand_extra_isize_ea, we
potentionally return from the function without having freed these
allocations.  If we don't do the return, we over-write the previous
allocation pointers, so we leak either way.

Spotted with Coverity.

[ Fixed by tytso to set is and bs to NULL after freeing these
  pointers, in case in the retry loop we later end up triggering an
  error causing a jump to cleanup, at which point we could have a double
  free bug. -- Ted ]

Signed-off-by: Dave Jones 
Signed-off-by: "Theodore Ts'o" 
Reviewed-by: Eric Sandeen 
Signed-off-by: Greg Kroah-Hartman

vfs: allow O_PATH file descriptors for fstatfs()

2013-10-22T08:02:25+00:00

commit 9d05746e7b16d8565dddbe3200faa1e669d23bbf upstream.

Olga reported that file descriptors opened with O_PATH do not work with
fstatfs(), found during further development of ksh93's thread support.

There is no reason to not allow O_PATH file descriptors here (fstatfs is
very much a path operation), so use "fdget_raw()".  See commit
55815f70147d ("vfs: make O_PATH file descriptors usable for 'fstat()'")
for a very similar issue reported for fstat() by the same team.

Reported-and-tested-by: ольга крыжановская 
Acked-by: Al Viro 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

random: run random_int_secret_init() run after all late_initcalls

2013-10-22T08:02:25+00:00

commit 47d06e532e95b71c0db3839ebdef3fe8812fca2c upstream.

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.

Signed-off-by: "Theodore Ts'o" 
Signed-off-by: Greg Kroah-Hartman