printk: fix syslog() overflowing user buffer

This is not a buffer overflow in the traditional sense: we don't
overflow any *kernel* buffers, but we do mis-count the amount of data we
copy back to user space for the SYSLOG_ACTION_READ_ALL case.

In particular, if the user buffer is too small to hold everything, and
*if* there is a continuation line at just the right place, we can end up
giving the user more data than he asked for.

The reason is that we first count up the number of bytes all the log
records contains, then we walk the records again until we've skipped the
records at the beginning that won't fit, and then we walk the rest of
the records and copy them to the user space buffer.

And in between that "skip the initial records that won't fit" and the
"copy the records that *will* fit to user space", we reset the 'prev'
variable that contained the record information for the last record not
copied.  That meant that when we started copying to user space, we now
had a different character count than what we had originally calculated
in the first record walk-through.

The fix is to simply not clear the 'prev' flags value (in both cases
where we had the same logic: syslog_print_all and kmsg_dump_get_buffer:
the latter is used for pstore-like dumping)

Reported-and-tested-by: Debabrata Banerjee <dbanerje@akamai.com>
Acked-by: Kay Sievers <kay@vrfy.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

Pull powerpc fixes from Ben Herrenschmidt:
 "Here are some more powerpc fixes for 3.14

  The main one is a nasty issue with the NUMA balancing support which
  requires a small generic change and the addition of a new accessor to
  set _PAGE_NUMA.  Both have been reviewed and acked by Mel and Rik.

  The changelog should have plenty of details but basically, without
  this fix, we get random user segfaults and/or corruptions due to
  missing TLB/hash flushes.  Aneesh series of 3 patches fixes it.

  We have some vDSO vs.  perf fixes from Anton, some small EEH fixes
  from Gavin, a ppc32 regression vs the stack overflow detector, and a
  fix for the way we handle PCIe host bridge speed settings on pseries
  (which is needed for proper operations of AMD graphics cards on
  Power8)"

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc/eeh: Disable EEH on reboot
  powerpc/eeh: Cleanup on eeh_subsystem_enabled
  powerpc/powernv: Rework EEH reset
  powerpc: Use unstripped VDSO image for more accurate profiling data
  powerpc: Link VDSOs at 0x0
  mm: Use ptep/pmdp_set_numa() for updating _PAGE_NUMA bit
  mm: Dirty accountable change only apply to non prot numa case
  powerpc/mm: Add new "set" flag argument to pte/pmd update function
  powerpc/pseries: Add Gen3 definitions for PCIE link speed
  powerpc/pseries: Fix regression on PCI link speed
  powerpc: Set the correct ksp_limit on ppc32 when switching to irq stack
ceph: properly handle XATTR_CREATE and XATTR_REPLACE

return -EEXIST if XATTR_CREATE is set and xattr alread exists.
return -ENODATA if XATTR_REPLACE is set but xattr does not exist.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
ceph: remove xattr when null value is given to setxattr()

For the setxattr request, introduce a new flag CEPH_XATTR_REMOVE
to distinguish null value case from the zero-length value case.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
ceph: fix ceph_removexattr()

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
ceph: fix ceph_set_acl()

If acl is equivalent to file mode permission bits, ceph_set_acl()
needs to remove any existing acl xattr. Use __ceph_setxattr() to
handle both setting and removing acl xattr cases, it doesn't return
-ENODATA when there is no acl xattr.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
ceph: add missing init_acl() for mkdir() and atomic_open()

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
ceph: make ceph_forget_all_cached_acls() static inline

Signed-off-by: Guangliang Zhao <lucienchao@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Sage Weil <sage@inktank.com>
ceph: add acl, noacl options for cephfs mount

Make the 'acl' option dependent on having ACL support compiled in.  Make
the 'noacl' option work even without it so that one can always ask it to
be off and not error out on mount when it is not supported.

Signed-off-by: Guangliang Zhao <lucienchao@gmail.com>
Signed-off-by: Sage Weil <sage@inktank.com>
ceph: fix __dcache_readdir()

If directory is fragmented, readdir() read its dirfrags one by one.
After reading all dirfrags, the corresponding dentries are sorted in
(frag_t, off) order in the dcache. If dentries of a directory are all
cached, __dcache_readdir() can use the cached dentries to satisfy
readdir syscall. But when checking if a given dentry is after the
position of readdir, __dcache_readdir() compares numerical value of
frag_t directly. This is wrong, it should use ceph_frag_compare().

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/egtvedt/linux-avr32

Pull AVR32 fixes from Hans-Christian Egtvedt.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/egtvedt/linux-avr32:
  avr32: add generic vga.h to Kbuild
  avr32: add generic ioremap_wc() definition in io.h
  avr32: Makefile: add '-D__linux__' flag for gcc-4.4.7 use
  avr32: fix missing module.h causing build failure in mimc200/fram.c
Merge tag 'dma-buf-for-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/sumits/dma-buf

Pull dma-buf fix from Sumit Semwal:
 "Just some debugfs output updates.

  There's another patch related to dma-buf, but it'll get upstreamed via
  Greg KH's pull request"

* tag 'dma-buf-for-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/sumits/dma-buf:
  dma-buf: update debugfs output
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless into for-davem
irtty-sir.c: Do not set_termios() on irtty_close()

Issuing set_termios() from irtty_close() causes kernel Oops for
unplugged usb-serial devices.

Since no other tty_ldisc calls set_termios() on close and no tty driver
seem to check if tty->device_data is NULL or not on entry to set_termios(),
the only solution I can come up with is to remove the irtty_stop_receiver()
call, which only updates termios.

Signed-off-by: Tommie Gannert <tommie@gannert.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
reiserfs: fix utterly brain-damaged indentation.

This has been this way for years, and every time I stumble across it I
lose my lunch.  After coming across it for the nth time in the Coverity
results, I had to overcome the bystander effect and do something about
it.

This ignores the 79 column limit in favor of making it look like C
instead of gibberish.

The correct thing to do here would be to lose some of the indentation by
breaking this function up into several smaller ones.  I might do that at
some point if I have the stomach to look at this again.

(Also some of those overlong ternary operations would likely be more
readable as regular if's)

Signed-off-by: Dave Jones <davej@fedoraproject.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
FS-Cache: Handle removal of unadded object to the fscache_object_list rb tree

When FS-Cache allocates an object, the following sequence of events can
occur:

 -->fscache_alloc_object()
    -->cachefiles_alloc_object() [via cache->ops->alloc_object]
    <--[returns new object]
    -->fscache_attach_object()
    <--[failed]
    -->cachefiles_put_object() [via cache->ops->put_object]
       -->fscache_object_destroy()
          -->fscache_objlist_remove()
             -->rb_erase() to remove the object from fscache_object_list.

resulting in a crash in the rbtree code.

The problem is that the object is only added to fscache_object_list on
the success path of fscache_attach_object() where it calls
fscache_objlist_add().

So if fscache_attach_object() fails, the object won't have been added to
the objlist rbtree.  We do, however, unconditionally try to remove the
object from the tree.

Thanks to NeilBrown for finding this and suggesting this solution.

Reported-by: NeilBrown <neilb@suse.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: (a customer of) NeilBrown <neilb@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'for-linus' of git://git.samba.org/sfrench/cifs-2.6

Pull CIFS fixes from Steve French:
 "Three cifs fixes, the most important fixing the problem with passing
  bogus pointers with writev (CVE-2014-0069).

  Two additional cifs fixes are still in review (including the fix for
  an append problem which Al also discovered)"

* 'for-linus' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Fix too big maxBuf size for SMB3 mounts
  cifs: ensure that uncached writes handle unmapped areas correctly
  [CIFS] Fix cifsacl mounts over smb2 to not call cifs
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

Pull Ceph fixes from Sage Weil:
 "We have some patches fixing up ACL support issues from Zheng and
  Guangliang and a mount option to enable/disable this support.  (These
  fixes were somewhat delayed by the Chinese holiday.)

  There is also a small fix for cached readdir handling when directories
  are fragmented"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  ceph: fix __dcache_readdir()
  ceph: add acl, noacl options for cephfs mount
  ceph: make ceph_forget_all_cached_acls() static inline
  ceph: add missing init_acl() for mkdir() and atomic_open()
  ceph: fix ceph_set_acl()
  ceph: fix ceph_removexattr()
  ceph: remove xattr when null value is given to setxattr()
  ceph: properly handle XATTR_CREATE and XATTR_REPLACE
ipv4: fix counter in_slow_tot

since commit 89aef8921bf("ipv4: Delete routing cache."), the counter
in_slow_tot can't work correctly.

The counter in_slow_tot increase by one when fib_lookup() return successfully
in ip_route_input_slow(), but actually the dst struct maybe not be created and
cached, so we can increase in_slow_tot after the dst struct is created.

Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix uses of dma_max_pfn() when converting to a limiting address

We must use a 64-bit for this, otherwise overflowed bits get lost, and
that can result in a lower than intended value set.

Fixes: 8e0cb8a1f6ac ("ARM: 7797/1: mmc: Use dma_max_pfn(dev) helper for bounce_limit calculations")
Fixes: 7d35496dd982 ("ARM: 7796/1: scsi: Use dma_max_pfn(dev) helper for bounce_limit calculations")
Tested-Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>