Commit 3812c8c8f395 ("mm: memcg: do not trap chargers with full
callstack on OOM") assumed that only a few places that can trigger a
memcg OOM situation do not return VM_FAULT_OOM, like optional page cache
readahead. But there are many more and it's impractical to annotate
them all.
First of all, we don't want to invoke the OOM killer when the failed
allocation is gracefully handled, so defer the actual kill to the end of
the fault handling as well. This simplifies the code quite a bit for
added bonus.
Second, since a failed allocation might not be the abrupt end of the
fault, the memcg OOM handler needs to be re-entrant until the fault
finishes for subsequent allocation attempts. If an allocation is
attempted after the task already OOMed, allow it to bypass the limit so
that it can quickly finish the fault and invoke the OOM killer.
Reported-by: azurIt <azurit@pobox.sk> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The memcg OOM handling is incredibly fragile and can deadlock. When a
task fails to charge memory, it invokes the OOM killer and loops right
there in the charge code until it succeeds. Comparably, any other task
that enters the charge path at this point will go to a waitqueue right
then and there and sleep until the OOM situation is resolved. The problem
is that these tasks may hold filesystem locks and the mmap_sem; locks that
the selected OOM victim may need to exit.
For example, in one reported case, the task invoking the OOM killer was
about to charge a page cache page during a write(), which holds the
i_mutex. The OOM killer selected a task that was just entering truncate()
and trying to acquire the i_mutex:
The OOM handling task will retry the charge indefinitely while the OOM
killed task is not releasing any resources.
A similar scenario can happen when the kernel OOM killer for a memcg is
disabled and a userspace task is in charge of resolving OOM situations.
In this case, ALL tasks that enter the OOM path will be made to sleep on
the OOM waitqueue and wait for userspace to free resources or increase
the group's limit. But a userspace OOM handler is prone to deadlock
itself on the locks held by the waiting tasks. For example one of the
sleeping tasks may be stuck in a brk() call with the mmap_sem held for
writing but the userspace handler, in order to pick an optimal victim,
may need to read files from /proc/<pid>, which tries to acquire the same
mmap_sem for reading and deadlocks.
This patch changes the way tasks behave after detecting a memcg OOM and
makes sure nobody loops or sleeps with locks held:
1. When OOMing in a user fault, invoke the OOM killer and restart the
fault instead of looping on the charge attempt. This way, the OOM
victim can not get stuck on locks the looping task may hold.
2. When OOMing in a user fault but somebody else is handling it
(either the kernel OOM killer or a userspace handler), don't go to
sleep in the charge context. Instead, remember the OOMing memcg in
the task struct and then fully unwind the page fault stack with
-ENOMEM. pagefault_out_of_memory() will then call back into the
memcg code to check if the -ENOMEM came from the memcg, and then
either put the task to sleep on the memcg's OOM waitqueue or just
restart the fault. The OOM victim can no longer get stuck on any
lock a sleeping task may hold.
Debugged by Michal Hocko.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reported-by: azurIt <azurit@pobox.sk> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The memcg OOM handler open-codes a sleeping lock for OOM serialization
(trylock, wait, repeat) because the required locking is so specific to
memcg hierarchies. However, it would be nice if this construct would be
clearly recognizable and not be as obfuscated as it is right now. Clean
up as follows:
1. Remove the return value of mem_cgroup_oom_unlock()
2. Rename mem_cgroup_oom_lock() to mem_cgroup_oom_trylock().
3. Pull the prepare_to_wait() out of the memcg_oom_lock scope. This
makes it more obvious that the task has to be on the waitqueue
before attempting to OOM-trylock the hierarchy, to not miss any
wakeups before going to sleep. It just didn't matter until now
because it was all lumped together into the global memcg_oom_lock
spinlock section.
4. Pull the mem_cgroup_oom_notify() out of the memcg_oom_lock scope.
It is proctected by the hierarchical OOM-lock.
5. The memcg_oom_lock spinlock is only required to propagate the OOM
lock in any given hierarchy atomically. Restrict its scope to
mem_cgroup_oom_(trylock|unlock).
6. Do not wake up the waitqueue unconditionally at the end of the
function. Only the lockholder has to wake up the next in line
after releasing the lock.
Note that the lockholder kicks off the OOM-killer, which in turn
leads to wakeups from the uncharges of the exiting task. But a
contender is not guaranteed to see them if it enters the OOM path
after the OOM kills but before the lockholder releases the lock.
Thus there has to be an explicit wakeup after releasing the lock.
7. Put the OOM task on the waitqueue before marking the hierarchy as
under OOM as that is the point where we start to receive wakeups.
No point in listening before being on the waitqueue.
8. Likewise, unmark the hierarchy before finishing the sleep, for
symmetry.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: azurIt <azurit@pobox.sk> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The x86 fault handler bails in the middle of error handling when the
task has a fatal signal pending. For a subsequent patch this is a
problem in OOM situations because it relies on pagefault_out_of_memory()
being called even when the task has been killed, to perform proper
per-task OOM state unwinding.
Shortcutting the fault like this is a rather minor optimization that
saves a few instructions in rare cases. Just remove it for
user-triggered faults.
Use the opportunity to split the fault retry handling from actual fault
errors and add locking documentation that reads suprisingly similar to
ARM's.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: azurIt <azurit@pobox.sk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Unlike global OOM handling, memory cgroup code will invoke the OOM killer
in any OOM situation because it has no way of telling faults occuring in
kernel context - which could be handled more gracefully - from
user-triggered faults.
Pass a flag that identifies faults originating in user space from the
architecture-specific fault handlers to generic code so that memcg OOM
handling can be improved.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: azurIt <azurit@pobox.sk> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Kernel faults are expected to handle OOM conditions gracefully (gup,
uaccess etc.), so they should never invoke the OOM killer. Reserve this
for faults triggered in user context when it is the only option.
Most architectures already do this, fix up the remaining few.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: azurIt <azurit@pobox.sk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The memcg code can trap tasks in the context of the failing allocation
until an OOM situation is resolved. They can hold all kinds of locks
(fs, mm) at this point, which makes it prone to deadlocking.
This series converts memcg OOM handling into a two step process that is
started in the charge context, but any waiting is done after the fault
stack is fully unwound.
Patches 1-4 prepare architecture handlers to support the new memcg
requirements, but in doing so they also remove old cruft and unify
out-of-memory behavior across architectures.
Patch 5 disables the memcg OOM handling for syscalls, readahead, kernel
faults, because they can gracefully unwind the stack with -ENOMEM. OOM
handling is restricted to user triggered faults that have no other
option.
Patch 6 reworks memcg's hierarchical OOM locking to make it a little
more obvious wth is going on in there: reduce locked regions, rename
locking functions, reorder and document.
Patch 7 implements the two-part OOM handling such that tasks are never
trapped with the full charge stack in an OOM situation.
This patch:
Back before smart OOM killing, when faulting tasks were killed directly on
allocation failures, the arch-specific fault handlers needed special
protection for the init process.
Now that all fault handlers call into the generic OOM killer (see commit 609838cfed97: "mm: invoke oom-killer from remaining unconverted page
fault handlers"), which already provides init protection, the
arch-specific leftovers can be removed.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: azurIt <azurit@pobox.sk> Acked-by: Vineet Gupta <vgupta@synopsys.com> [arch/arc bits] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A few remaining architectures directly kill the page faulting task in an
out of memory situation. This is usually not a good idea since that
task might not even use a significant amount of memory and so may not be
the optimal victim to resolve the situation.
Since 2.6.29's 1c0fe6e ("mm: invoke oom-killer from page fault") there
is a hook that architecture page fault handlers are supposed to call to
invoke the OOM killer and let it pick the right task to kill. Convert
the remaining architectures over to this hook.
To have the previous behavior of simply taking out the faulting task the
vm.oom_kill_allocating_task sysctl can be set to 1.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> [arch/arc bits] Cc: James Hogan <james.hogan@imgtec.com> Cc: David Howells <dhowells@redhat.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Chen Liqin <liqin.chen@sunplusct.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Chris Metcalf <cmetcalf@tilera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 6f4c618ddb0 ("SCTP : Add paramters validity check for
ASCONF chunk") added basic verification of ASCONF chunks, however,
it is still possible to remotely crash a server by sending a
special crafted ASCONF chunk, even up to pre 2.6.12 kernels:
... where ASCONF chunk of length 280 contains 2 parameters ...
1) Add IP address parameter (param length: 16)
2) Add/del IP address parameter (param length: 255)
... followed by an UNKNOWN chunk of e.g. 4 bytes. Here, the
Address Parameter in the ASCONF chunk is even missing, too.
This is just an example and similarly-crafted ASCONF chunks
could be used just as well.
The ASCONF chunk passes through sctp_verify_asconf() as all
parameters passed sanity checks, and after walking, we ended
up successfully at the chunk end boundary, and thus may invoke
sctp_process_asconf(). Parameter walking is done with
WORD_ROUND() to take padding into account.
In sctp_process_asconf()'s TLV processing, we may fail in
sctp_process_asconf_param() e.g., due to removal of the IP
address that is also the source address of the packet containing
the ASCONF chunk, and thus we need to add all TLVs after the
failure to our ASCONF response to remote via helper function
sctp_add_asconf_response(), which basically invokes a
sctp_addto_chunk() adding the error parameters to the given
skb.
When walking to the next parameter this time, we proceed
with ...
... instead of the WORD_ROUND()'ed length, thus resulting here
in an off-by-one that leads to reading the follow-up garbage
parameter length of 12336, and thus throwing an skb_over_panic
for the reply when trying to sctp_addto_chunk() next time,
which implicitly calls the skb_put() with that length.
Fix it by using sctp_walk_params() [ which is also used in
INIT parameter processing ] macro in the verification *and*
in ASCONF processing: it will make sure we don't spill over,
that we walk parameters WORD_ROUND()'ed. Moreover, we're being
more defensive and guard against unknown parameter types and
missized addresses.
Joint work with Vlad Yasevich.
Fixes: b896b82be4ae ("[SCTP] ADDIP: Support for processing incoming ASCONF_ACK chunks.") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
... where ASCONF_a equals ASCONF_b chunk (at least both serials
need to be equal), we panic an SCTP server!
The problem is that good-formed ASCONF chunks that we reply with
ASCONF_ACK chunks are cached per serial. Thus, when we receive a
same ASCONF chunk twice (e.g. through a lost ASCONF_ACK), we do
not need to process them again on the server side (that was the
idea, also proposed in the RFC). Instead, we know it was cached
and we just resend the cached chunk instead. So far, so good.
Where things get nasty is in SCTP's side effect interpreter, that
is, sctp_cmd_interpreter():
While incoming ASCONF_a (chunk = event_arg) is being marked
!end_of_packet and !singleton, and we have an association context,
we do not flush the outqueue the first time after processing the
ASCONF_ACK singleton chunk via SCTP_CMD_REPLY. Instead, we keep it
queued up, although we set local_cork to 1. Commit 2e3216cd54b1
changed the precedence, so that as long as we get bundled, incoming
chunks we try possible bundling on outgoing queue as well. Before
this commit, we would just flush the output queue.
Now, while ASCONF_a's ASCONF_ACK sits in the corked outq, we
continue to process the same ASCONF_b chunk from the packet. As
we have cached the previous ASCONF_ACK, we find it, grab it and
do another SCTP_CMD_REPLY command on it. So, effectively, we rip
the chunk->list pointers and requeue the same ASCONF_ACK chunk
another time. Since we process ASCONF_b, it's correctly marked
with end_of_packet and we enforce an uncork, and thus flush, thus
crashing the kernel.
Fix it by testing if the ASCONF_ACK is currently pending and if
that is the case, do not requeue it. When flushing the output
queue we may relink the chunk for preparing an outgoing packet,
but eventually unlink it when it's copied into the skb right
before transmission.
Joint work with Vlad Yasevich.
Fixes: 2e3216cd54b1 ("sctp: Follow security requirement of responding with 1 packet") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
... where ASCONF_a, ASCONF_b, ..., ASCONF_z are good-formed
ASCONFs and have increasing serial numbers, we process such
ASCONF chunk(s) marked with !end_of_packet and !singleton,
since we have not yet reached the SCTP packet end. SCTP does
only do verification on a chunk by chunk basis, as an SCTP
packet is nothing more than just a container of a stream of
chunks which it eats up one by one.
We could run into the case that we receive a packet with a
malformed tail, above marked as trailing JUNK. All previous
chunks are here goodformed, so the stack will eat up all
previous chunks up to this point. In case JUNK does not fit
into a chunk header and there are no more other chunks in
the input queue, or in case JUNK contains a garbage chunk
header, but the encoded chunk length would exceed the skb
tail, or we came here from an entirely different scenario
and the chunk has pdiscard=1 mark (without having had a flush
point), it will happen, that we will excessively queue up
the association's output queue (a correct final chunk may
then turn it into a response flood when flushing the
queue ;)): I ran a simple script with incremental ASCONF
serial numbers and could see the server side consuming
excessive amount of RAM [before/after: up to 2GB and more].
The issue at heart is that the chunk train basically ends
with !end_of_packet and !singleton markers and since commit 2e3216cd54b1 ("sctp: Follow security requirement of responding
with 1 packet") therefore preventing an output queue flush
point in sctp_do_sm() -> sctp_cmd_interpreter() on the input
chunk (chunk = event_arg) even though local_cork is set,
but its precedence has changed since then. In the normal
case, the last chunk with end_of_packet=1 would trigger the
queue flush to accommodate possible outgoing bundling.
In the input queue, sctp_inq_pop() seems to do the right thing
in terms of discarding invalid chunks. So, above JUNK will
not enter the state machine and instead be released and exit
the sctp_assoc_bh_rcv() chunk processing loop. It's simply
the flush point being missing at loop exit. Adding a try-flush
approach on the output queue might not work as the underlying
infrastructure might be long gone at this point due to the
side-effect interpreter run.
One possibility, albeit a bit of a kludge, would be to defer
invalid chunk freeing into the state machine in order to
possibly trigger packet discards and thus indirectly a queue
flush on error. It would surely be better to discard chunks
as in the current, perhaps better controlled environment, but
going back and forth, it's simply architecturally not possible.
I tried various trailing JUNK attack cases and it seems to
look good now.
Joint work with Vlad Yasevich.
Fixes: 2e3216cd54b1 ("sctp: Follow security requirement of responding with 1 packet") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit fc3a9157d314 ("KVM: X86: Don't report L2 emulation failures to
user-space") disabled the reporting of L2 (nested guest) emulation failures to
userspace due to race-condition between a vmexit and the instruction emulator.
The same rational applies also to userspace applications that are permitted by
the guest OS to access MMIO area or perform PIO.
This patch extends the current behavior - of injecting a #UD instead of
reporting it to userspace - also for guest userspace code.
Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When the driver calls scsi_done and after that frees it's internal
preallocated memory it can happen that a new job is enqueud before
the memory is freed. The allocation fails and the message
"cmd_alloc returned NULL" is shown.
Patch below fixes it by moving cmd->scsi_done after cmd_free.
Signed-off-by: Tomas Henzl <thenzl@redhat.com> Acked-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com> Cc: Masoud Sharbiani <msharbiani@twitter.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix a race between BlueFlame flow and stamping in post send flow.
Example:
SW: Build WQE 0 on the TX buffer, except the ownership bit
SW: Set ownership for WQE 0 on the TX buffer
SW: Ring doorbell for WQE 0
SW: Build WQE 1 on the TX buffer, except the ownership bit
SW: Set ownership for WQE 1 on the TX buffer
HW: Read WQE 0 and then WQE 1, before doorbell was rung/BF was done for WQE 1
HW: Produce CQEs for WQE 0 and WQE 1
SW: Process the CQEs, and stamp WQE 0 and WQE 1 accordingly (on the TX buffer)
SW: Copy WQE 1 from the TX buffer to the BF register - ALREADY STAMPED!
HW: CQE error with index 0xFFFF - the BF WQE's control segment is STAMPED,
so the BF index is 0xFFFF. Error: Invalid Opcode.
As a result QP enters the error state and no traffic can be sent.
Solution:
When stamping - do not stamp last completed wqe.
Signed-off-by: Eugenia Emantayev <eugenia@mellanox.com> Signed-off-by: Amir Vadai <amirv@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Vinson Lee <vlee@twopensource.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently BUG() uses .word or .hword to create the necessary illegal
instructions. However if we are building BE8 then these get swapped
by the linker into different illegal instructions in the text. This
means that the BUG() macro does not get trapped properly.
Change to using <asm/opcodes.h> to provide the necessary ARM instruction
building as we cannot rely on gcc/gas having the `.inst` instructions
which where added to try and resolve this issue (reported by Dave Martin
<Dave.Martin@arm.com>).
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Cc: Wang Nan <wangnan0@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On IvyBridge we share the SandyBridge cache event tables, but the
dTLB-load-miss event is not compatible. Patch it up after
the fact to the proper DTLB_LOAD_MISSES.DEMAND_LD_MISS_CAUSES_A_WALK
function 'strncpy' will fill whole buffer 'id.name' of fixed size (32)
with string value and will not leave place for NULL-terminator.
Possible buffer boundaries violation in following string operations.
Replace strncpy with strlcpy.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When running a 32-bit userspace on a 64-bit kernel (eg. i386
application on x86_64 kernel or 32-bit arm userspace on arm64
kernel) some of the perf ioctls must be treated with special
care, as they have a pointer size encoded in the command.
For example, PERF_EVENT_IOC_ID in 32-bit world will be encoded
as 0x80042407, but 64-bit kernel will expect 0x80082407. In
result the ioctl will fail returning -ENOTTY.
This patch solves the problem by adding code fixing up the
size as compat_ioctl file operation.
Reported-by: Drew Richardson <drew.richardson@arm.com> Signed-off-by: Pawel Moll <pawel.moll@arm.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1402671812-9078-1-git-send-email-pawel.moll@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: David Ahern <daahern@cisco.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Without this patch, dell-wmi is trying to access elements of dynamically
allocated array without checking the array size. This can lead to memory
corruption or a kernel panic. This patch adds the missing checks for
array size.
If we are running BE8, the data and instruction endianness do not
match, so use <asm/opcodes.h> to correctly translate memory accesses
into ARM instructions.
Acked-by: Jon Medhurst <tixy@linaro.org> Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
[taras.kondratiuk@linaro.org: fixed Thumb instruction fetch order] Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
[wangnan: backport to 3.10 and 3.14:
- adjust context
- backport all changes on arch/arm/kernel/probes.c to
arch/arm/kernel/kprobes-common.c since we don't have
commit c18377c303787ded44b7decd7dee694db0f205e9.
- After the above adjustments, becomes same to Taras Kondratiuk's
original patch:
http://lists.linaro.org/pipermail/linaro-kernel/2014-January/010346.html
] Signed-off-by: Wang Nan <wangnan0@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
br_stp_rcv() is reached by non-rx_handler path. That means there is no
guarantee that dev is bridge port and therefore simple NULL check of
->rx_handler_data is not enough. There is need to check if dev is really
bridge port and since only rcu read lock is held here, do it by checking
->rx_handler pointer.
Note that synchronize_net() in netdev_rx_handler_unregister() ensures
this approach as valid.
Reported-by: Laine Stump <laine@redhat.com> Debugged-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jiri Pirko <jiri@resnulli.us> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Andrew Collins <bsderandrew@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Basically what's happening is, during netns cleanup,
nf_nat_net_exit gets called before ipv4_net_exit. As I understand
it, nf_nat_net_exit is supposed to kill any conntrack entries which
have NAT context (through nf_ct_iterate_cleanup), but for some
reason this doesn't happen (perhaps something else is still holding
refs to those entries?).
When ipv4_net_exit is called, conntrack entries (including those
with NAT context) are cleaned up, but the
nat_bysource hashtable is long gone - freed in nf_nat_net_exit. The
bug happens when attempting to free a conntrack entry whose NAT hash
'prev' field points to a slot in the freed hash table (head for that
bin).
We ignore conntracks with null nat bindings. But this is wrong,
as these are in bysource hash table as well.
Restore nat-cleaning for the netns-is-being-removed case.
This structure is not exposed to userspace, so fix this by defining
struct sk_filter; so we skip the casting in kernelspace. This is safe
since userspace has no way to lurk with that internal pointer.
Fixes: e6f30c7 ("netfilter: x_tables: add xt_bpf match") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The kernel should reserve enough room in the skb so that the DONE
message can always be appended. However, in case of e.g. new attribute
erronously not being size-accounted for, __nfulnl_send() will still
try to put next nlmsg into this full skbuf, causing the skb to be stuck
forever and blocking delivery of further messages.
Fix issue by releasing skb immediately after nlmsg_put error and
WARN() so we can track down the cause of such size mismatch.
[ fw@strlen.de: add tailroom/len info to WARN ]
Signed-off-by: Houcheng Lin <houcheng@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
don't try to queue payloads > 0xffff - NLA_HDRLEN, it does not work.
The nla length includes the size of the nla struct, so anything larger
results in u16 integer overflow.
This patch is similar to 9cefbbc9c8f9abe (netfilter: nfnetlink_queue: cleanup copy_range usage).
We currently neither account for the nlattr size, nor do we consider
the size of the trailing NLMSG_DONE when allocating nlmsg skb.
This can result in nflog to stop working, as __nfulnl_send() re-tries
sending forever if it failed to append NLMSG_DONE (which will never
work if buffer is not large enough).
Reported-by: Houcheng Lin <houcheng@gmail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernel/time/jiffies.c provides a default clocksource_default_clock()
definition explicitly marked "weak". arch/s390 provides its own definition
intended to override the default, but the "weak" attribute on the
declaration applied to the s390 definition as well, so the linker chose one
based on link order (see 10629d711ed7 ("PCI: Remove __weak annotation from
pcibios_get_phb_of_node decl")).
Remove the "weak" attribute from the clocksource_default_clock()
declaration so we always prefer a non-weak definition over the weak one,
independent of link order.
Fixes: f1b82746c1e9 ("clocksource: Cleanup clocksource selection") Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: John Stultz <john.stultz@linaro.org> Acked-by: Ingo Molnar <mingo@kernel.org> CC: Daniel Lezcano <daniel.lezcano@linaro.org> CC: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernel/debug/debug_core.c provides a default kgdb_arch_pc() definition
explicitly marked "weak". Several architectures provide their own
definitions intended to override the default, but the "weak" attribute on
the declaration applied to the arch definitions as well, so the linker
chose one based on link order (see 10629d711ed7 ("PCI: Remove __weak
annotation from pcibios_get_phb_of_node decl")).
Remove the "weak" attribute from the declaration so we always prefer a
non-weak definition over the weak one, independent of link order.
Any attempt to call nfs_remove_bad_delegation() while a delegation is being
returned is currently a no-op. This means that we can end up looping
forever in nfs_end_delegation_return() if something causes the delegation
to be revoked.
This patch adds a mechanism whereby the state recovery code can communicate
to the delegation return code that the delegation is no longer valid and
that it should not be used when reclaiming state.
It also changes the return value for nfs4_handle_delegation_recall_error()
to ensure that nfs_end_delegation_return() does not reattempt the lock
reclaim before state recovery is done.
Variable 'err' needn't be initialized when nfs_getattr() uses it to
check whether it should call generic_fillattr() or not. That can result
in spurious error returns. Initialize 'err' properly.
Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
NFSv4.0 does not have TEST_STATEID/FREE_STATEID functionality, so
unlike NFSv4.1, the recovery procedure when stateids have expired or
have been revoked requires us to just forget the delegation.
On some Dell Latitude laptops ALPS device or Dell EC send one invalid byte
in 6 bytes ALPS packet. In this case psmouse driver enter out of sync
state. It looks like that all other bytes in packets are valid and also
device working properly. So there is no need to do full device reset, just
need to wait for byte which match condition for first byte (start of
packet). Because ALPS packets are bigger (6 or 8 bytes) default limit is
small.
This patch increase number of invalid bytes to size of 2 ALPS packets which
psmouse driver can drop before do full reset.
Resetting ALPS devices take some time and when doing reset on some Dell
laptops touchpad, trackstick and also keyboard do not respond. So it is
better to do it only if really necessary.
5th and 6th byte of ALPS trackstick V3 protocol match condition for first
byte of PS/2 3 bytes packet. When driver enters out of sync state and ALPS
trackstick is sending data then driver match 5th, 6th and next 1st bytes as
PS/2.
It basically means if user is using trackstick when driver is in out of
sync state driver will never resync. Processing these bytes as 3 bytes PS/2
data cause total mess (random cursor movements, random clicks) and make
trackstick unusable until psmouse driver decide to do full device reset.
Lot of users reported problems with ALPS devices on Dell Latitude E6440,
E6540 and E7440 laptops. ALPS device or Dell EC for unknown reason send
some invalid ALPS PS/2 bytes which cause driver out of sync. It looks like
that i8042 and psmouse/alps driver always receive group of 6 bytes packets
so there are no missing bytes and no bytes were inserted between valid
ones.
This patch does not fix root of problem with ALPS devices found in Dell
Latitude laptops but it does not allow to process some (invalid)
subsequence of 6 bytes ALPS packets as 3 bytes PS/2 when driver is out of
sync.
So with this patch trackstick input device does not report bogus data when
also driver is out of sync, so trackstick should be usable on those
machines.
The dm-raid superblock (struct dm_raid_superblock) is padded to 512
bytes and that size is being used to read it in from the metadata
device into one preallocated page.
Reading or writing this on a 512-byte sector device works fine but on
a 4096-byte sector device this fails.
Set the dm-raid superblock's size to the logical block size of the
metadata device, because IO at that size is guaranteed too work. Also
add a size check to avoid silent partial metadata loss in case the
superblock should ever grow past the logical block size or PAGE_SIZE.
[includes pointer math fix from Dan Carpenter] Reported-by: "Liuhua Wang" <lwang@suse.com> Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The walk code was using a 'ro_spine' to hold it's locked btree nodes.
But this data structure is designed for the rolling lock scheme, and
as such automatically unlocks blocks that are two steps up the call
chain. This is not suitable for the simple recursive walk algorithm,
which retraces its steps.
This code is only used by the persistent array code, which in turn is
only used by dm-cache. In order to trigger it you need to have a
mapping tree that is more than 2 levels deep; which equates to 8-16
million cache blocks. For instance a 4T ssd with a very small block
size of 32k only just triggers this bug.
The fix just places the locked blocks on the stack, and stops using
the ro_spine altogether.
Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Priority of a merged request is computed by ioprio_best(). If one of the
requests has undefined priority (IOPRIO_CLASS_NONE) and another request
has priority from IOPRIO_CLASS_BE, the function will return the
undefined priority which is wrong. Fix the function to properly return
priority of a request with the defined priority.
Fixes: d58cdfb89ce0c6bd5f81ae931a984ef298dbda20 Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Switch over the msgctl, shmat, shmctl and semtimedop syscalls to use the compat
layer. The problem was found with the debian procenv package, which called
shmctl(0, SHM_INFO, &info);
in which the shmctl syscall then overwrote parts of the surrounding areas on
the stack on which the info variable was stored and thus lead to a segfault
later on.
Additionally fix the definition of struct shminfo64 to use unsigned longs like
the other architectures. This has no impact on userspace since we only have a
32bit userspace up to now.
Signed-off-by: Helge Deller <deller@gmx.de> Cc: John David Anglin <dave.anglin@bell.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Setups that use the blk-mq I/O path can lock up if a host with a single
device that has its door locked enters EH. Make sure to only send the
command to re-lock the door to devices that actually were reset and thus
might have lost their state. Otherwise the EH code might be get blocked
on blk_get_request as all requests for non-reset devices might be in use.
Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Meelis Roos <meelis.roos@ut.ee> Tested-by: Meelis Roos <meelis.roos@ut.ee> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For pNFS direct writes, layout driver may dynamically allocate ds_cinfo.buckets.
So we need to take care to free them when freeing dreq.
Ideally this needs to be done inside layout driver where ds_cinfo.buckets
are allocated. But buckets are attached to dreq and reused across LD IO iterations.
So I feel it's OK to free them in the generic layer.
Found by the UC-KLEE tool: A user could supply less input to
firewire-cdev ioctls than write- or write/read-type ioctl handlers
expect. The handlers used data from uninitialized kernel stack then.
This could partially leak back to the user if the kernel subsequently
generated fw_cdev_event_'s (to be read from the firewire-cdev fd)
which notably would contain the _u64 closure field which many of the
ioctl argument structures contain.
The fact that the handlers would act on random garbage input is a
lesser issue since all handlers must check their input anyway.
The fix simply always null-initializes the entire ioctl argument buffer
regardless of the actual length of expected user input. That is, a
runtime overhead of memset(..., 40) is added to each firewirew-cdev
ioctl() call. [Comment from Clemens Ladisch: This part of the stack is
most likely to be already in the cache.]
Remarks:
- There was never any leak from kernel stack to the ioctl output
buffer itself. IOW, it was not possible to read kernel stack by a
read-type or write/read-type ioctl alone; the leak could at most
happen in combination with read()ing subsequent event data.
- The actual expected minimum user input of each ioctl from
include/uapi/linux/firewire-cdev.h is, in bytes:
[0x00] = 32, [0x05] = 4, [0x0a] = 16, [0x0f] = 20, [0x14] = 16,
[0x01] = 36, [0x06] = 20, [0x0b] = 4, [0x10] = 20, [0x15] = 20,
[0x02] = 20, [0x07] = 4, [0x0c] = 0, [0x11] = 0, [0x16] = 8,
[0x03] = 4, [0x08] = 24, [0x0d] = 20, [0x12] = 36, [0x17] = 12,
[0x04] = 20, [0x09] = 24, [0x0e] = 4, [0x13] = 40, [0x18] = 4.
Reported-by: David Ramos <daramos@stanford.edu> Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ARM64 currently doesn't fix up faults on the single-byte (strb) case of
__clear_user... which means that we can cause a nasty kernel panic as an
ordinary user with any multiple PAGE_SIZE+1 read from /dev/zero.
i.e.: dd if=/dev/zero of=foo ibs=1 count=1 (or ibs=65537, etc.)
This is a pretty obscure bug in the general case since we'll only
__do_kernel_fault (since there's no extable entry for pc) if the
mmap_sem is contended. However, with CONFIG_DEBUG_VM enabled, we'll
always fault.
if (!down_read_trylock(&mm->mmap_sem)) {
if (!user_mode(regs) && !search_exception_tables(regs->pc))
goto no_context;
retry:
down_read(&mm->mmap_sem);
} else {
/*
* The above down_read_trylock() might have succeeded in
* which
* case, we'll have missed the might_sleep() from
* down_read().
*/
might_sleep();
if (!user_mode(regs) && !search_exception_tables(regs->pc))
goto no_context;
}
Fix that by adding an extable entry for the strb instruction, since it
touches user memory, similar to the other stores in __clear_user.
The kuser helpers page is not set up on non-MMU systems, so it does
not make sense to allow CONFIG_KUSER_HELPERS to be enabled when
CONFIG_MMU=n. Allowing it to be set on !MMU results in an oops in
set_tls (used in execve and the arm_syscall trap handler):
As best I can tell this issue existed for the set_tls ARM syscall
before commit fbfb872f5f41 "ARM: 8148/1: flush TLS and thumbee
register state during exec" consolidated the TLS manipulation code
into the set_tls helper function, but now that we're using it to flush
register state during execve, !MMU users encounter the oops at the
first exec.
Prevent CONFIG_MMU=n configurations from enabling
CONFIG_KUSER_HELPERS.
Fixes: fbfb872f5f41 (ARM: 8148/1: flush TLS and thumbee register state during exec) Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com> Reported-by: Stefan Agner <stefan@agner.ch> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Upon receiving the last fragment, all but the first fragment
are freed, but the multicast check for statistics at the end
of the function refers to the current skb (the last fragment)
causing a use-after-free bug.
Since multicast frames cannot be fragmented and we check for
this early in the function, just modify that check to also
do the accounting to fix the issue.
When VLAN is in use in macvtap_put_user, we end up setting
csum_start to the wrong place. The result is that the whoever
ends up doing the checksum setting will corrupt the packet instead
of writing the checksum to the expected location, usually this
means writing the checksum with an offset of -4.
This patch fixes this by adjusting csum_start when VLAN tags are
detected.
Fixes: f09e2249c4f5 ("macvtap: restore vlan header on user read") Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
The LTR is the handshake between the device and the root
complex about the latency allowed when the bus exits power
save. This configuration was missing and this led to high
latency in the link power up. The end user could experience
high latency in the network because of this.
Large (greater than 32k, the value of PAGE_ALLOC_COSTLY_ORDER) auth
tickets will have their buffers vmalloc'ed, which leads to the
following crash in crypto:
Userspace actually passes single parameter (path name) to the umount
syscall, so new umount just fails. Fix it by requesting old umount
syscall implementation and re-wiring umount to it.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Samsung pci-e SSDs on macbooks failed miserably on NCQ commands, so 67809f85d31e ("ahci: disable NCQ on Samsung pci-e SSDs on macbooks")
disabled NCQ on them. It turns out that NCQ is fine as long as MSI is
not used, so let's turn off MSI and leave NCQ on.
Signed-off-by: Tejun Heo <tj@kernel.org> Link: https://bugzilla.kernel.org/show_bug.cgi?id=60731 Tested-by: <dorin@i51.org> Tested-by: Imre Kaloz <kaloz@openwrt.org> Fixes: 67809f85d31e ("ahci: disable NCQ on Samsung pci-e SSDs on macbooks") Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Audit rules disappear when an inode they watch is evicted from the cache.
This is likely not what we want.
The guilty commit is "fsnotify: allow marks to not pin inodes in core",
which didn't take into account that audit_tree adds watches with a zero
mask.
Adding any mask should fix this.
Fixes: 90b1e7a57880 ("fsnotify: allow marks to not pin inodes in core") Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Paul Moore <pmoore@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Atomicity between xchg and cmpxchg cannot be guaranteed when xchg is
implemented with a swap and cmpxchg is implemented with locks.
Without this, e.g. mcs_spin_lock and mcs_spin_unlock are broken.
Signed-off-by: Andreas Larsson <andreas@gaisler.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Otherwise rcu_irq_{enter,exit}() do not happen and we get dumps like:
====================
[ 188.275021] ===============================
[ 188.309351] [ INFO: suspicious RCU usage. ]
[ 188.343737] 3.18.0-rc3-00068-g20f3963-dirty #54 Not tainted
[ 188.394786] -------------------------------
[ 188.429170] include/linux/rcupdate.h:883 rcu_read_lock() used
illegally while idle!
[ 188.505235]
other info that might help us debug this:
Based almost entirely upon a patch by Paul E. McKenney.
Reported-by: Meelis Roos <mroos@linux.ee> Tested-by: Meelis Roos <mroos@linux.ee> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This code is trying to go through the standard PCI config space
interfaces to read the PCI controller's PCI_STATUS register.
This doesn't work, because we more often than not do not enumerate
the PCI controller as a bonafide PCI device during the OF device
node scan. Therefore bus->self remains NULL.
Existing common code for PSYCHO and PSYCHO-like PCI controllers
handles this properly, by doing the config space access directly.
Do the same here, pbm->pci_ops->{read,write}().
Reported-by: Meelis Roos <mroos@linux.ee> Tested-by: Meelis Roos <mroos@linux.ee> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The VD_OP_GET_VTOC operation will succeed only if the vdisk backend has a
VTOC label, otherwise it will fail. In particular, it will return error
48 (ENOTSUP) if the disk has an EFI label. VTOC disk labels are already
handled by directly reading the disk in block/partitions/sun.c (enabled by
CONFIG_SUN_PARTITION which defaults to y on SPARC). Since port->label is
unused in the driver, remove the call and the field.
Signed-off-by: Dwight Engen <dwight.engen@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vio_dring_avail() will allow use of every dring entry, but when the last
entry is allocated then dr->prod == dr->cons which is indistinguishable from
the ring empty condition. This causes the next allocation to reuse an entry.
When this happens in sunvdc, the server side vds driver begins nack'ing the
messages and ends up resetting the ldc channel. This problem does not effect
sunvnet since it checks for < 2.
The fix here is to just never allocate the very last dring slot so that full
and empty are not the same condition. The request start path was changed to
check for the ring being full a bit earlier, and to stop the blk_queue if
there is no space left. The blk_queue will be restarted once the ring is
only half full again. The number of ring entries was increased to 512 which
matches the sunvnet and Solaris vdc drivers, and greatly reduces the
frequency of hitting the ring full condition and the associated blk_queue
stop/starting. The checks in sunvent were adjusted to account for
vio_dring_avail() returning 1 less.
Signed-off-by: Dwight Engen <dwight.engen@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ldc_map_sg() could fail its check that the number of pages referred to
by the sg scatterlist was <= the number of cookies.
This fixes the issue by doing a similar thing to the xen-blkfront driver,
ensuring that the scatterlist will only ever contain a segment count <=
port->ring_cookies, and each segment will be page aligned, and <= page
size. This ensures that the scatterlist is always mappable.
Signed-off-by: Dwight Engen <dwight.engen@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The LDom diskserver doesn't return reliable geometry data. In addition,
the types for all fields in the vio_disk_geom are u16, which were being
truncated in the cast into the u8's of the Linux struct hd_geometry.
Modify vdc_getgeo() to compute the geometry from the disk's capacity in a
manner consistent with xen-blkfront::blkif_getgeo().
Signed-off-by: Dwight Engen <dwight.engen@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Interpret the media type from v1.1 protocol to support CDROM/DVD.
For v1.0 protocol, a disk's size continues to be calculated from the
geometry returned by the vdisk server. The geometry returned by the server
can be less than the actual number of sectors available in the backing
image/device due to the rounding in the division used to compute the
geometry in the vdisk server.
In v1.1 protocol a disk's actual size in sectors is returned during the
handshake. Use this size when v1.1 protocol is negotiated. Since this size
will always be larger than the former geometry computed size, disks created
under v1.0 will be forwards compatible to v1.1, but not vice versa.
Signed-off-by: Dwight Engen <dwight.engen@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A very minimal and simple user space application allocating an SCTP
socket, setting SCTP_AUTH_KEY setsockopt(2) on it and then closing
the socket again will leak the memory containing the authentication
key from user space:
This is bad because of two things, we can bring down a machine from
user space when auth_enable=1, but also we would leave security sensitive
keying material in memory without clearing it after use. The issue is
that sctp_auth_create_key() already sets the refcount to 1, but after
allocation sctp_auth_set_key() does an additional refcount on it, and
thus leaving it around when we free the socket.
Fixes: 65b07e5d0d0 ("[SCTP]: API updates to suport SCTP-AUTH extensions.") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
While the INIT chunk parameter verification dissects through many things
in order to detect malformed input, it misses to actually check parameters
inside of parameters. E.g. RFC5061, section 4.2.4 proposes a 'set primary
IP address' parameter in ASCONF, which has as a subparameter an address
parameter.
So an attacker may send a parameter type other than SCTP_PARAM_IPV4_ADDRESS
or SCTP_PARAM_IPV6_ADDRESS, param_type2af() will subsequently return 0
and thus sctp_get_af_specific() returns NULL, too, which we then happily
dereference unconditionally through af->from_addr_param().
A minimal way to address this is to check for NULL as we do on all
other such occasions where we know sctp_get_af_specific() could
possibly return with NULL.
Fixes: d6de3097592b ("[SCTP]: Add the handling of "Set Primary IP Address" parameter to INIT") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Otherwise it gets overwritten by register_netdev().
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ip6_tnl_dev_init() sets the dev->iflink via a call to
ip6_tnl_link_config(). After that, register_netdevice()
sets dev->iflink = -1. So we loose the iflink configuration
for ipv6 tunnels. Fix this by using ip6_tnl_dev_init() as the
ndo_init function. Then ip6_tnl_dev_init() is called after
dev->iflink is set to -1 from register_netdevice().
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit f363e45fd118 ("net/ceph: make ceph_msgr_wq non-reentrant")
effectively removed WQ_MEM_RECLAIM flag from ceph_msgr_wq. This is
wrong - libceph is very much a memory reclaim path, so restore it.
If we hit any errors in btrfs_lookup_csums_range, we'll loop through all
the csums we allocate and free them. But the code was using list_entry
incorrectly, and ended up trying to free the on-stack list_head instead.
The string property read helpers will run off the end of the buffer if
it is handed a malformed string property. Rework the parsers to make
sure that doesn't happen. At the same time add new test cases to make
sure the functions behave themselves.
The original implementations of of_property_read_string_index() and
of_property_count_strings() both open-coded the same block of parsing
code, each with it's own subtly different bugs. The fix here merges
functions into a single helper and makes the original functions static
inline wrappers around the helper.
One non-bugfix aspect of this patch is the addition of a new wrapper,
of_property_read_string_array(). The new wrapper is needed by the
device_properties feature that Rafael is working on and planning to
merge for v3.19. The implementation is identical both with and without
the new static inline wrapper, so it just got left in to reduce the
churn on the header file.
Signed-off-by: Grant Likely <grant.likely@linaro.org> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Rob Herring <robh+dt@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Darren Hart <darren.hart@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a race condition when removing glue directory.
It can be reproduced in following test:
path 1: Add first child device
device_add()
get_device_parent()
/*find parent from glue_dirs.list*/
list_for_each_entry(k, &dev->class->p->glue_dirs.list, entry)
if (k->parent == parent_kobj) {
kobj = kobject_get(k);
break;
}
....
class_dir_create_and_add()
path2: Remove last child device under glue dir
device_del()
cleanup_device_parent()
cleanup_glue_dir()
kobject_put(glue_dir);
If path2 has been called cleanup_glue_dir(), but not
call kobject_put(glue_dir), the glue dir is still
in parent's kset list. Meanwhile, path1 find the glue
dir from the glue_dirs.list. Path2 may release glue dir
before path1 call kobject_get(). So kernel will report
the warning and bug_on.
This is a "classic" problem we have of a kref in a list
that can be found while the last instance could be removed
at the same time.
This patch reuse gdp_mutex to fix this race condition.
The following calltrace is captured in kernel 3.4, but
the latest kernel still has this bug.
The acpi-video backlight interface on the Acer KAV80 is broken, and worse
it causes the entire machine to slow down significantly after a suspend/resume.
Blacklist it, and use the acer-wmi backlight interface instead. Note that
the KAV80 is somewhat unique in that it is the only Acer model where we
fall back to acer-wmi after blacklisting, rather then using the native
(e.g. intel) backlight driver. This is done because there is no native
backlight interface on this model.
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1128309 Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When we fail to allocate page vector in rbd_obj_read_sync() we just
basically ignore the problem and continue which will result in an oops
later. Fix the problem by returning proper error.
CC: Yehuda Sadeh <yehuda@inktank.com> CC: Sage Weil <sage@inktank.com> CC: ceph-devel@vger.kernel.org
Coverity-id: 1226882 Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Ilya Dryomov <idryomov@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, there's no guarantee that udc->driver
will be valid when using soft_connect sysfs
interface. In fact, we can very easily trigger
a NULL pointer dereference by trying to disconnect
when a gadget driver isn't loaded.
During Halt Endpoint Test, our interrupt endpoint
will be disabled, which will clear out ep->desc
to NULL. Unless we call config_ep_by_speed() again,
we will not be able to enable this endpoint which
will make us fail that test.
Fixes: f9c56cd (usb: gadget: Clear usb_endpoint_descriptor
inside the struct usb_ep on disable) Signed-off-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
According to our Gadget Framework API documentation,
->set_halt() *must* return -EAGAIN if we have pending
transfers (on either direction) or FIFO isn't empty (on
TX endpoints).
Fix this bug so that the mass storage gadget can be used
without stall=0 parameter.
This patch should be backported to all kernels since v3.2.
Suggested-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On archs with PAGE_SIZE >= 64 KiB the function skcipher_alloc_sgl()
fails with -ENOMEM no matter what user space actually requested.
This is caused by the fact sock_kmalloc call inside the function tried
to allocate more memory than allowed by the default kernel socket buffer
size (kernel param net.core.optmem_max).
Signed-off-by: Ondrej Kozina <okozina@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The WARN_ON checking whether i_mutex is held in
pagecache_isize_extended() was wrong because some filesystems (e.g.
XFS) use different locks for serialization of truncates / writes. So
just remove the check.
Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the TSC is unusable or disabled, then this patch fixes:
- Confusion while trying to clear old APIC interrupts.
- Division by zero and incorrect programming of the TSC deadline
timer.
This fixes boot if the CPU has a TSC deadline timer but a missing or
broken TSC. The failure to boot can be observed with qemu using
-cpu qemu64,-tsc,+tsc-deadline
This also happens to me in nested KVM for unknown reasons.
With this patch, I can boot cleanly (although without a TSC).
If userland creates a timer without specifying a sigevent info, we'll
create one ourself, using a stack local variable. Particularly will we
use the timer ID as sival_int. But as sigev_value is a union containing
a pointer and an int, that assignment will only partially initialize
sigev_value on systems where the size of a pointer is bigger than the
size of an int. On such systems we'll copy the uninitialized stack bytes
from the timer_create() call to userland when the timer actually fires
and we're going to deliver the signal.
Initialize sigev_value with 0 to plug the stack info leak.
It affects non-(V)HT rates and can lead to selecting an rts_cts rate
that is not a basic rate or way superior to the reference rate (ATM
rates[0] used for the 1st attempt of the protected frame data).
E.g, assuming drivers register growing (bitrate) sorted tables of
ieee80211_rate-s, having :
- rates[0].idx == d'2 and basic_rates == b'10100
will select rts_cts idx b'10011 & ~d'(BIT(2)-1), i.e. 1, likewise
- rates[0].idx == d'2 and basic_rates == b'10001
will select rts_cts idx b'10000
The first is not a basic rate and the second is > rates[0].
Also, wrt severity of the addressed misbehavior, ATM we only have one
rts_cts_rate_idx rather than one per rate table entry, so this idx might
still point to bitrates > rates[1..MAX_RATES].
Fixes: 5253ffb8c9e1 ("mac80211: always pick a basic rate to tx RTS/CTS for pre-HT rates") Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a device's dev_pm_ops::freeze callback fails during the QUIESCE
phase, we don't rollback things correctly calling the thaw and complete
callbacks. This could leave some devices in a suspended state in case of
an error during resuming from hibernation.
Signed-off-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Kernel oops can cause the tty to be unreleaseable (for example, if
n_tty_read() crashes while on the read_wait queue). This will cause
tty_release() to endlessly loop without sleeping.
Use a killable sleep timeout which grows by 2n+1 jiffies over the interval
[0, 120 secs.) and then jumps to forever (but still killable).
NB: killable just allows for the task to be rewoken manually, not
to be terminated.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Due to a switched left and right side of an assignment,
dquot_writeback_dquots() never returned error. This could result in
errors during quota writeback to not be reported to userspace properly.
Fix it.
Coverity-id: 1226884 Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The check whether quota format is set even though there are no
quota files with journalled quota is pointless and it actually
makes it impossible to turn off journalled quotas (as there's
no way to unset journalled quota format). Just remove the check.
Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Unknown operation numbers are caught in nfsd4_decode_compound() which
sets op->opnum to OP_ILLEGAL and op->status to nfserr_op_illegal. The
error causes the main loop in nfsd4_proc_compound() to skip most
processing. But nfsd4_proc_compound also peeks ahead at the next
operation in one case and doesn't take similar precautions there.
Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When sg_scsi_ioctl() fails to prepare request to submit in
blk_rq_map_kern() we jump to a label where we just end up copying
(luckily zeroed-out) kernel buffer to userspace instead of reporting
error. Fix the problem by jumping to the right label.
CC: Jens Axboe <axboe@kernel.dk> CC: linux-scsi@vger.kernel.org
Coverity-id: 1226871 Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixed up the, now unused, out label.
If __bitmap_shift_left() or __bitmap_shift_right() are asked to shift by
a multiple of BITS_PER_LONG, they will try to shift a long value by
BITS_PER_LONG bits which is undefined. Change the functions to avoid
the undefined shift.
Coverity id: 1192175
Coverity id: 1192174 Signed-off-by: Jan Kara <jack@suse.cz> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit ff7ee93f4715 ("cgroup/kmemleak: Annotate alloc_page() for cgroup
allocations") introduces kmemleak_alloc() for alloc_page_cgroup(), but
corresponding kmemleak_free() is missing, which makes kmemleak be
wrongly disabled after memory offlining. Log is pasted at the end of
this commit message.
This patch add kmemleak_free() into free_page_cgroup(). During page
offlining, this patch removes corresponding entries in kmemleak rbtree.
After that, the freed memory can be allocated again by other subsystems
without killing kmemleak.
bash # for x in 1 2 3 4; do echo offline > /sys/devices/system/memory/memory$x/state ; sleep 1; done ; dmesg | grep leak