Update {get,put}_user macros for m32r kernel.
- Modify get_user to use __get_user_asm macro, instead of __get_user_x macro.
- Remove arch/m32r/lib/{get,put}user.S.
- Some cosmetic updates.
I would like to thank NIIBE Yutaka for his reporting about the m32r kernel's
security problem in {get,put}_user macros.
There were no address checking for user space access in {get,put}_user macros.
;-)
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Cc: NIIBE Yutaka <gniibe@fsij.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch fixes a boot problem of the m32r SMP kernel 2.6.16-rc1-mm3 or
later.
In this patch, cpu_possible_map is statically initialized, and cpu_present_map
is also copied from cpu_possible_map in smp_prepare_cpus(), because the m32r
architecture has not supported CPU hotplug yet.
Signed-off-by: Hayato Fujiwara <fujiwara.hayato@renesas.com>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I've encountered two problems with 2.6.16 and newer kernels on my API CS20
(dual 833MHz Alpha 21264b processors). The first is the kernel OOPSing
because of a NULL pointer dereference while trying to populate SysFS with the
CPU information. The other is that only one processor was being brought up.
I've included a small Alpha-specific patch that fixes both problems.
The first problem was caused by the CPUs never being properly registered using
register_cpu(), the way it's done on other architectures.
The second problem has to do with the removal of hwrpb_cpu_present_mask in
arch/alpha/kernel/smp.c. In setup_smp() in the 2.6.15 kernel sources,
hwrpb_cpu_present_mask has a bit set for each processor that is probed, and
afterwards cpu_present_mask is set to the cpumask for the boot CPU. In the
same function of the same file in the 2.6.16 sources, instead of
hwrpb_cpu_present_mask being set, cpu_possible_map is updated for each probed
CPU. cpu_present_mask is still set to the cpumask of the boot CPU afterwards.
The problem lies in include/asm-alpha/smp.h, where cpu_possible_map is
#define'd to be cpu_present_mask.
Cleanups from: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
- cpu_present_mask and cpu_possible_map are essentially the same thing
on alpha, as it doesn't support CPU hotplug;
- allocate "struct cpu" only for present CPUs, like sparc64 does.
Static array of "struct cpu" is just a waste of memory.
Signed-off-by: Brian Uhrain <buhrain@rosettastone.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Geode GX/LX should enable X86_TSC. Pointed out by Adrian Bunk.
Signed-off-by: Jordan Crouse <jordan.crouse@amd.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Since several subarchs depend on SMP, the SMP option should be above the
subarch selection.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
John Z. Bohach <jzb@aexorsyst.com> found this bug:
If the board has more than 32 PCI busses on it, the mptable bus array will
overwrite its bounds for the PCI busses, and stomp on anything that's after
it.
Prevent possible table overflow and unknown data corruption. Code is in an
__init section so it will be discarded after init.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Move the DOUBLEFAULT option from the top-level menu to the EMBEDDED menu.
Only applicable to X86_32.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Print summary registers (EIP and SS:ESP only) as last death info. This
makes this important data visible in case it had scrolled off the top of
the display. Similar to what x86_64 does. Suggested by Andi Kleen.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Switching to automatic bigsmp causes a misleading error message, that more
then 8 cpus are detected, and user needs to select either X86_GENERICARCH
or X86_BIGSMP to handle.
Reason is we switched to bigsmp to avoid IP race when new cpu is comming
up. [bigsmp is nothing but using physical flat mode that can work for 1 ..
255 cpus] [default is X86_PC, that uses logical flat mode up to 8 CPUs
max] Current x86_64 code uses bigsmp as default when hotplug is enabled.
It would be preferable to make bigsmp as default, and work the dependencies
of other related code like SMP_SUSPEND, and some related to memory hotplug
code for i386.
Current logical flat mode doesnt use shortcuts that cause the race by using
the send_IPI_mask() instead of shortcuts when HOTPLUG_CPU is enabled.
In the meantime this patch is the path of lease resistance.
We will switch to bigsmp default sometime soon, when we get to work it again.
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Nigel Cunningham <nigel@suspend2.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
For some architectures, a few syscalls are not linked in noMMU mode. In
that case, the MMU depending syscalls are needed to be defined as
'cond_syscall'. For example, ARM architecture selectively links sys_mlock
by the mode configuration.
In case of FRV, it has been managed by #ifdef CONFIG_MMU macro in
arch/frv/kernel/entry.S. However these conditional macros are just
duplicates if they were defined as cond_syscall. Compilation test is done
with FRV toolchains for both of MMU and noMMU mode.
Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
EXPORT_SYMBOL'ing of a static function is not a good idea.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add some documentation regarding the utilisation of the flags field in
struct page. This field is overloaded for per page bits and to hold node,
zone and SPARSEMEM information. Make it clear which areas are used for
what and how many bits are in each area.
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch is an enhancement of OVERCOMMIT_GUESS algorithm in
__vm_enough_memory() in mm/nommu.c.
When the OVERCOMMIT_GUESS algorithm calculates the number of free pages,
the algorithm subtracts the number of reserved pages from the result
nr_free_pages().
Signed-off-by: Hideo Aoki <haoki@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch is an enhancement of OVERCOMMIT_GUESS algorithm in
__vm_enough_memory() in mm/mmap.c.
When the OVERCOMMIT_GUESS algorithm calculates the number of free pages,
the algorithm subtracts the number of reserved pages from the result
nr_free_pages().
Signed-off-by: Hideo Aoki <haoki@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
These patches are an enhancement of OVERCOMMIT_GUESS algorithm in
__vm_enough_memory().
- why the kernel needed patching
When the kernel can't allocate anonymous pages in practice, currnet
OVERCOMMIT_GUESS could return success. This implementation might be
the cause of oom kill in memory pressure situation.
If the Linux runs with page reservation features like
/proc/sys/vm/lowmem_reserve_ratio and without swap region, I think
the oom kill occurs easily.
- the overall design approach in the patch
When the OVERCOMMET_GUESS algorithm calculates number of free pages,
the reserved free pages are regarded as non-free pages.
This change helps to avoid the pitfall that the number of free pages
become less than the number which the kernel tries to keep free.
- testing results
I tested the patches using my test kernel module.
If the patches aren't applied to the kernel, __vm_enough_memory()
returns success in the situation but autual page allocation is
failed.
On the other hand, if the patches are applied to the kernel, memory
allocation failure is avoided since __vm_enough_memory() returns
failure in the situation.
I checked that on i386 SMP 16GB memory machine. I haven't tested on
nommu environment currently.
This patch adds totalreserve_pages for __vm_enough_memory().
Calculate_totalreserve_pages() checks maximum lowmem_reserve pages and
pages_high in each zone. Finally, the function stores the sum of each
zone to totalreserve_pages.
The totalreserve_pages is calculated when the VM is initilized.
And the variable is updated when /proc/sys/vm/lowmem_reserve_raito
or /proc/sys/vm/min_free_kbytes are changed.
Signed-off-by: Hideo Aoki <haoki@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The code checks for newbrk with oldbrk which are page aligned before making
a check for the memory limit set of data segment. If the memory limit is
not page aligned in that case it bypasses the test for the limit if the
memory allocation is still for the same page.
Signed-off-by: Ram Gupta <ram.gupta5@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The earlier patch to consolidate mmu and nommu page allocation and
refcounting by using compound pages for nommu allocations had a bug:
kmalloc slabs who's pages were initially allocated by a non-__GFP_COMP
allocator could be passed into mm/nommu.c kmalloc allocations which really
wanted __GFP_COMP underlying pages. Fix that by having nommu pass
__GFP_COMP to all higher order slab allocations.
Signed-off-by: Luke Yang <luke.adi@gmail.com>
Acked-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add a statistics counter which is incremented everytime the alien cache
overflows. alien_cache limit is hardcoded to 12 right now. We can use
this statistics to tune alien cache if needed in the future.
Signed-off-by: Alok N Kataria <alokk@calsoftinc.com>
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
for_each_cpu() actually iterates across all possible CPUs. We've had mistakes
in the past where people were using for_each_cpu() where they should have been
iterating across only online or present CPUs. This is inefficient and
possibly buggy.
We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the
future.
This patch replaces for_each_cpu with for_each_possible_cpu.
for sparc64.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
for_each_cpu() actually iterates across all possible CPUs. We've had mistakes
in the past where people were using for_each_cpu() where they should have been
iterating across only online or present CPUs. This is inefficient and
possibly buggy.
We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the
future.
This patch replaces for_each_cpu with for_each_possible_cpu.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
for_each_cpu() actually iterates across all possible CPUs. We've had mistakes
in the past where people were using for_each_cpu() where they should have been
iterating across only online or present CPUs. This is inefficient and
possibly buggy.
We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the
future.
This patch replaces for_each_cpu with for_each_possible_cpu under /net
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch switches arch/i386/mach-voyager/voyager_cat.c to using named
initializers for struct resource.
Besides a fixing compile error in Greg's tree, it makes the code more
readable.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
reshape_position is a 64bit field that was not 64bit aligned. So swap with
new_level.
NOTE: this is a user-visible change. However:
- The bad code has not appeared in a released kernel
- This code is still marked 'experimental'
- This only affects version-1 superblock, which are not in wide use
- These field are only used (rather than simply reported) by user-space
tools in extemely rare circumstances : after a reshape crashes in the
first second of the reshape process.
So I believe that, at this stage, the change is safe. Especially if people
heed the 'help' message on use mdadm-2.4.1.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
zone_pcp() only returns valid values if the processor is online.
Change node_read_numastat() to only scan online processors.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
fs/select.c: In function `core_sys_select':
fs/select.c:339: warning: assignment from incompatible pointer type
fs/select.c:376: warning: comparison of distinct pointer types lacks a cast
By using a void* we can remove lots of casts rather than adding more.
Cc: Jes Sorensen <jes@trained-monkey.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
RT tasks are being awakened on the expired array when expired_starving() is
true, whereas they really should be excluded. Fix.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Con Kolivas <kernel@kolivas.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix a starvation problem that occurs when a stream of highly interactive tasks
delay an array switch for extended periods despite EXPIRED_STARVING(rq) being
true. AFAIKT, the only choice is to enqueue awakening tasks on the expired
array in this case.
Without this patch, it can be nearly impossible to remotely login to a busy
server, and interactive shell commands can starve for minutes.
Also, convert the EXPIRED_STARVING macro into an inline function which humans
can understand.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Acked-by: Con Kolivas <kernel@kolivas.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
that have been unlinked, we may need to execute transactions during
reclaim. By the time the transaction has hit the disk, the linux inode and
xfs vnode may already have been freed so we can't reference them safely.
Use the known xfs inode state to determine if it is safe to reference the
vnode and linux inode during the unpin operation.
SGI-PV: 946321
SGI-Modid: xfs-linux-melb:xfs-kern:25687a
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
millions of inodes cached and has sparse cluster population, removing
inodes from the cluster hash consumes excessive amounts of CPU time.
Reduce the CPU cost by making removal O(1) via use of a double linked list
for the hash chains.
SGI-PV: 951551
SGI-Modid: xfs-linux-melb:xfs-kern:25683a
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>
nonblock mode with the new IO path code (since 2.6.16).
SGI-PV: 951662
SGI-Modid: xfs-linux-melb:xfs-kern:25676a
Signed-off-by: Nathan Scott <nathans@sgi.com>
* master.kernel.org:/home/rmk/linux-2.6-arm:
[ARM] 3473/1: Use numbers 0-15 for the VFP double registers
[ARM] 3472/1: Use the D variants of FLDMIA/FSTMIA on ARMv6
[ARM] 3471/1: FTOSI functions should return 0 for NaN
[ARM] 3470/1: Clear the HWCAP bits for the disabled kernel features
[ARM] 3469/1: S3C24XX: clkout missing hclk selector
[ARM] 3468/1: S3C2410: SMDK common include fix
[ARM] 3461/1: ARM: OMAP: Fix clk_get() when using id and name
[ARM] 3460/1: ARM: OMAP: Remove unnecessary nop_release()
[ARM] 3459/1: ixp23xx: fix debug serial macros for big-endian operation
[ARM] Allow decompressor to be built with -ffunction-sections
[ARM] Fix SA110/SA1100 cache flushing
[ARM] ebsa110: Fix incorrect serial port address
[ARM] Fix ebsa110 debug macros
[ARM] Move FLUSH_BASE macros to asm/arch/memory.h
[ARM] Remove unnecessary extra parens in include/asm-arm/memory.h
[ARM] arm's arch_local_page_offset() fix against 2.6.17-rc1
* 'upstream-linus' of git://oss.oracle.com/home/sourcebo/git/ocfs2:
[PATCH] CONFIGFS_FS must depend on SYSFS
[PATCH] Bogus NULL pointer check in fs/configfs/dir.c
ocfs2: Better I/O error handling in heartbeat
ocfs2: test and set teardown flag early in user_dlm_destroy_lock()
ocfs2: Handle the DLM_CANCELGRANT case in user_unlock_ast()
ocfs2: catch an invalid ast case in dlmfs
ocfs2: remove an overly aggressive BUG() in dlmfs
ocfs2: multi node truncate fix
Oleg Nesterov spotted two interesting bugs with the current de_thread
code. The simplest is a long standing double decrement of
__get_cpu_var(process_counts) in __unhash_process. Caused by
two processes exiting when only one was created.
The other is that since we no longer detach from the thread_group list
it is possible for do_each_thread when run under the tasklist_lock to
see the same task_struct twice. Once on the task list as a
thread_group_leader, and once on the thread list of another
thread.
The double appearance in do_each_thread can cause a double increment
of mm_core_waiters in zap_threads resulting in problems later on in
coredump_wait.
To remedy those two problems this patch takes the simple approach
of changing the old thread group leader into a child thread.
The only routine in release_task that cares is __unhash_process,
and it can be trivially seen that we handle cleaning up a
thread group leader properly.
Since de_thread doesn't change the pid of the exiting leader process
and instead shares it with the new leader process. I change
thread_group_leader to recognize group leadership based on the
group_leader field and not based on pids. This should also be
slightly cheaper then the existing thread_group_leader macro.
I performed a quick audit and I couldn't see any user of
thread_group_leader that cared about the difference.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Patch from Catalin Marinas
This patch changes the double registers numbering to 0-15 from even 0-30,
in preparation for future VFP extensions. It also fixes the VFP_REG_ZERO
bug (value 16 actually represents the 8th double register with the original
numbering).
The original mcrr/mrrc on CP10 were generating FMRRS/FMSRR instead of
FMRRD/FMDRR. The patch changes to CP11 for the correct instructions.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Catalin Marinas
The X variants are deprecated starting with ARMv6. Using the D variants,
the fpmx_state in vfp_hard_struct is no longer needed.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Catalin Marinas
The NaN case was dealed with by the "exponent >= ... + 32" condition but it
was not setting the value "d" to 0.
Signed-off-by: Ken'ichi Kuromusha <musha@aplix.co.jp>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Catalin Marinas
Glibc interprets the HWCAP bits and decides on what features to use.
However, even if the features are present in the hardware, they are not
always supported by the kernel and hence the corresponding bits have to be
cleared from the elf_hwcap variable.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch fixes the a compile error with CONFIG_SYSFS=n
Configfs is creating, as a matter of policy, the /sys/kernel/config
mountpoint. This means it requires CONFIG_SYSFS.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
We check the "group" pointer after we dereference it. This check is
bogus, as it cannot be NULL coming in.
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Overriding the whole EH code is a per-transport, not per-host thing.
Move ->eh_strategy_handler to the transport class, same as
->eh_timed_out.
Downside is that scsi_host_alloc can't check for the total lack of EH
anymore, but the transition period from old EH where we needed it is
long gone already.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Rohit found an obscure bug causing buddy list corruption.
page_is_buddy is using a non-atomic test (PagePrivate && page_count == 0)
to determine whether or not a free page's buddy is itself free and in the
buddy lists.
Each of the conjuncts may be true at different times due to unrelated
conditions, so the non-atomic page_is_buddy test may find each conjunct to
be true even if they were not both true at the same time (ie. the page was
not on the buddy lists).
Signed-off-by: Martin Bligh <mbligh@google.com>
Signed-off-by: Rohit Seth <rohitseth@google.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This fixes the problem of an oops occuring when a user attempts to add a
key to a non-keyring key [CVE-2006-1522].
The problem is that __keyring_search_one() doesn't check that the
keyring it's been given is actually a keyring.
I've fixed this problem by:
(1) declaring that caller of __keyring_search_one() must guarantee that
the keyring is a keyring; and
(2) making key_create_or_update() check that the keyring is a keyring,
and return -ENOTDIR if it isn't.
This can be tested by:
keyctl add user b b `keyctl add user a a @s`
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
