init_espfix_ap() is currently off by one level when informing hypervisor
that allocated pages will be used for ministacks' page tables.
The most immediate effect of this on a PV guest is that if
'stack_page = __get_free_page()' returns a non-zeroed-out page the hypervisor
will refuse to use it for a page table (which it shouldn't be anyway). This will
result in warnings by both Xen and Linux.
More importantly, a subsequent write to that page (again, by a PV guest) is
likely to result in fatal page fault.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: http://lkml.kernel.org/r/1404926298-5565-1-git-send-email-boris.ostrovsky@oracle.com Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This moves the espfix64 logic into native_iret. To make this work,
it gets rid of the native patch for INTERRUPT_RETURN:
INTERRUPT_RETURN on native kernels is now 'jmp native_iret'.
This changes the 16-bit SS behavior on Xen from OOPSing to leaking
some bits of the Xen hypervisor's RSP (I think).
[ hpa: this is a nonzero cost on native, but probably not enough to
measure. Xen needs to fix this in their own code, probably doing
something equivalent to espfix64. ]
Embedded systems, which may be very memory-size-sensitive, are
extremely unlikely to ever encounter any 16-bit software, so make it
a CONFIG_EXPERT option to turn off support for any 16-bit software
whatsoever.
Make espfix64 a hidden Kconfig option. This fixes the x86-64 UML
build which had broken due to the non-existence of init_espfix_bsp()
in UML: since UML uses its own Kconfig, this option does not appear in
the UML build.
This also makes it possible to make support for 16-bit segments a
configuration option, for the people who want to minimize the size of
the kernel.
Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Richard Weinberger <richard@nod.at> Link: http://lkml.kernel.org/r/1398816946-3351-1-git-send-email-hpa@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Sparse warns that the percpu variables aren't declared before they are
defined. Rather than hacking around it, move espfix definitions into
a proper header file.
Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The IRET instruction, when returning to a 16-bit segment, only
restores the bottom 16 bits of the user space stack pointer. This
causes some 16-bit software to break, but it also leaks kernel state
to user space. We have a software workaround for that ("espfix") for
the 32-bit kernel, but it relies on a nonzero stack segment base which
is not available in 64-bit mode.
In checkin:
b3b42ac2cbae x86-64, modify_ldt: Ban 16-bit segments on 64-bit kernels
we "solved" this by forbidding 16-bit segments on 64-bit kernels, with
the logic that 16-bit support is crippled on 64-bit kernels anyway (no
V86 support), but it turns out that people are doing stuff like
running old Win16 binaries under Wine and expect it to work.
This works around this by creating percpu "ministacks", each of which
is mapped 2^16 times 64K apart. When we detect that the return SS is
on the LDT, we copy the IRET frame to the ministack and use the
relevant alias to return to userspace. The ministacks are mapped
readonly, so if IRET faults we promote #GP to #DF which is an IST
vector and thus has its own stack; we then do the fixup in the #DF
handler.
(Making #GP an IST exception would make the msr_safe functions unsafe
in NMI/MC context, and quite possibly have other effects.)
Special thanks to:
- Andy Lutomirski, for the suggestion of using very small stack slots
and copy (as opposed to map) the IRET frame there, and for the
suggestion to mark them readonly and let the fault promote to #DF.
- Konrad Wilk for paravirt fixup and testing.
- Borislav Petkov for testing help and useful comments.
Reported-by: Brian Gerst <brgerst@gmail.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1398816946-3351-1-git-send-email-hpa@linux.intel.com Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Andrew Lutomriski <amluto@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Dirk Hohndel <dirk@hohndel.org> Cc: Arjan van de Ven <arjan.van.de.ven@intel.com> Cc: comex <comexk@gmail.com> Cc: Alexander van Heukelum <heukelum@fastmail.fm> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
In types.h this pattern was not followed and here
we only checked for __sparc__ for no good reason.
It was a left-over from long time ago.
I checked other architectures - and most of them
do not have any such checks. And all the recently
merged versions uses the asm-generic version.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
[bwh: Guenter backported this to 3.2:
- Adjusted filenames, context
- There's no duplicate export of types.h to delete] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
slab_node() could access current->mempolicy from interrupt context.
However there's a race condition during exit where the mempolicy
is first freed and then the pointer zeroed.
Using this from interrupts seems bogus anyways. The interrupt
will interrupt a random process and therefore get a random
mempolicy. Many times, this will be idle's, which noone can change.
Just disable this here and always use local for slab
from interrupts. I also cleaned up the callers of slab_node a bit
which always passed the same argument.
I believe the original mempolicy code did that in fact,
so it's likely a regression.
v2: send version with correct logic
v3: simplify. fix typo. Reported-by: Arun Sharma <asharma@fb.com> Cc: penberg@kernel.org Cc: cl@linux.com Signed-off-by: Andi Kleen <ak@linux.intel.com>
[tdmackey@twitter.com: Rework control flow based on feedback from
cl@linux.com, fix logic, and cleanup current task_struct reference] Acked-by: David Rientjes <rientjes@google.com> Acked-by: Christoph Lameter <cl@linux.com> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: David Mackey <tdmackey@twitter.com> Signed-off-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This commit is a guesswork, but it seems to make sense to drop this
break, as otherwise the following line is never executed and becomes
dead code. And that following line actually saves the result of
local calculation by the pointer given in function argument. So the
proposed change makes sense if this code in the whole makes sense (but I
am unable to analyze it in the whole).
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=81641 Reported-by: David Binderman <dcb314@hotmail.com> Signed-off-by: Andrey Utkin <andrey.krieger.utkin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The LDC handshake could have been asynchronously triggered
after ldc_bind() enables the ldc_rx() receive interrupt-handler
(and thus intercepts incoming control packets)
and before vio_port_up() calls ldc_connect(). If that is the case,
ldc_connect() should return 0 and let the state-machine
progress.
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Acked-by: Karl Volz <karl.volz@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fix detection of BREAK on sunsab serial console: BREAK detection was only
performed when there were also serial characters received simultaneously.
To handle all BREAKs correctly, the check for BREAK and the corresponding
call to uart_handle_break() must also be done if count == 0, therefore
duplicate this code fragment and pull it out of the loop over the received
characters.
Patch applies to 3.16-rc6.
Signed-off-by: Christopher Alexander Tobias Schulze <cat.schulze@alice-dsl.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fix regression in bbc i2c temperature and fan control on some Sun systems
that causes the driver to refuse to load due to the bbc_i2c_bussel resource not
being present on the (second) i2c bus where the temperature sensors and fan
control are located. (The check for the number of resources was removed when
the driver was ported to a pure OF driver in mid 2008.)
Signed-off-by: Christopher Alexander Tobias Schulze <cat.schulze@alice-dsl.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Based almost entirely upon a patch by Christopher Alexander Tobias
Schulze.
In commit db64fe02258f1507e13fe5212a989922323685ce ("mm: rewrite vmap
layer") lazy VMAP tlb flushing was added to the vmalloc layer. This
causes problems on sparc64.
Sparc64 has two VMAP mapped regions and they are not contiguous with
eachother. First we have the malloc mapping area, then another
unrelated region, then the vmalloc region.
This "another unrelated region" is where the firmware is mapped.
If the lazy TLB flushing logic in the vmalloc code triggers after
we've had both a module unload and a vfree or similar, it will pass an
address range that goes from somewhere inside the malloc region to
somewhere inside the vmalloc region, and thus covering the
openfirmware area entirely.
The sparc64 kernel learns about openfirmware's dynamic mappings in
this region early in the boot, and then services TLB misses in this
area. But openfirmware has some locked TLB entries which are not
mentioned in those dynamic mappings and we should thus not disturb
them.
These huge lazy TLB flush ranges causes those openfirmware locked TLB
entries to be removed, resulting in all kinds of problems including
hard hangs and crashes during reboot/reset.
Besides causing problems like this, such huge TLB flush ranges are
also incredibly inefficient. A plea has been made with the author of
the VMAP lazy TLB flushing code, but for now we'll put a safety guard
into our flush_tlb_kernel_range() implementation.
Since the implementation has become non-trivial, stop defining it as a
macro and instead make it a function in a C source file.
Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The assumption was that update_mmu_cache() (and the equivalent for PMDs) would
only be called when the PTE being installed will be accessible by the user.
This is not true for code paths originating from remove_migration_pte().
There are dire consequences for placing a non-valid PTE into the TSB. The TLB
miss frramework assumes thatwhen a TSB entry matches we can just load it into
the TLB and return from the TLB miss trap.
So if a non-valid PTE is in there, we will deadlock taking the TLB miss over
and over, never satisfying the miss.
Just exit early from update_mmu_cache() and friends in this situation.
Based upon a report and patch from Christopher Alexander Tobias Schulze.
Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Access to the TSB hash tables during TLB misses requires that there be
an atomic 128-bit quad load available so that we fetch a matching TAG
and DATA field at the same time.
On cpus prior to UltraSPARC-III only virtual address based quad loads
are available. UltraSPARC-III and later provide physical address
based variants which are easier to use.
When we only have virtual address based quad loads available this
means that we have to lock the TSB into the TLB at a fixed virtual
address on each cpu when it runs that process. We can't just access
the PAGE_OFFSET based aliased mapping of these TSBs because we cannot
take a recursive TLB miss inside of the TLB miss handler without
risking running out of hardware trap levels (some trap combinations
can be deep, such as those generated by register window spill and fill
traps).
Without huge pages it's working perfectly fine, but when the huge TSB
got added another chunk of fixed virtual address space was not
allocated for this second TSB mapping.
So we were mapping both the 8K and 4MB TSBs to the same exact virtual
address, causing multiple TLB matches which gives undefined behavior.
Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When a user process which is 32-bit performs a load or a store, the
cpu chops off the top 32-bits of the effective address before
translating it.
This is because we run 32-bit tasks with the PSTATE_AM (address
masking) bit set.
We can't run the kernel with that bit set, so when the kernel accesses
userspace no address masking occurs.
Since a 32-bit process will have no mappings in that region we will
properly fault, so we don't try to handle this using access_ok(),
which can safely just be a NOP on sparc64.
Real faults from 32-bit processes should never generate such addresses
so a bug check was added long ago, and it barks in the logs if this
happens.
But it also barks when a kernel user access causes this condition, and
that _can_ happen. For example, if a pointer passed into a system call
is "0xfffffffc" and the kernel access 4 bytes offset from that pointer.
Just handle such faults normally via the exception entries.
Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Next, make do_fault_siginfo() more robust when get_user_insn() can't
actually fetch the instruction. In particular, use the MMU announced
fault address when that happens, instead of calling
compute_effective_address() and computing garbage.
Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This is a followup of commits f1d8cba61c3c4b ("inet: fix possible
seqlock deadlocks") and 7f88c6b23afbd315 ("ipv6: fix possible seqlock
deadlock in ip6_finish_output2")
Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Reported-by: Dave Jones <davej@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Check for cases when the caller requests 0 bytes instead of running off
and dereferencing potentially invalid iovecs.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Macvlan devices do not initialize vlan_features. As a result,
any vlan devices configured on top of macvlans perform very poorly.
Initialize vlan_features based on the vlan features of the lower-level
device.
Signed-off-by: Vlad Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Jason reported an oops caused by SCTP on his ARM machine with
SCTP authentication enabled:
Internal error: Oops: 17 [#1] ARM
CPU: 0 PID: 104 Comm: sctp-test Not tainted 3.13.0-68744-g3632f30c9b20-dirty #1
task: c6eefa40 ti: c6f52000 task.ti: c6f52000
PC is at sctp_auth_calculate_hmac+0xc4/0x10c
LR is at sg_init_table+0x20/0x38
pc : [<c024bb80>] lr : [<c00f32dc>] psr: 40000013
sp : c6f538e8 ip : 00000000 fp : c6f53924
r10: c6f50d80 r9 : 00000000 r8 : 00010000
r7 : 00000000 r6 : c7be4000 r5 : 00000000 r4 : c6f56254
r3 : c00c8170 r2 : 00000001 r1 : 00000008 r0 : c6f1e660
Flags: nZcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user
Control: 0005397f Table: 06f28000 DAC: 00000015
Process sctp-test (pid: 104, stack limit = 0xc6f521c0)
Stack: (0xc6f538e8 to 0xc6f54000)
[...]
Backtrace:
[<c024babc>] (sctp_auth_calculate_hmac+0x0/0x10c) from [<c0249af8>] (sctp_packet_transmit+0x33c/0x5c8)
[<c02497bc>] (sctp_packet_transmit+0x0/0x5c8) from [<c023e96c>] (sctp_outq_flush+0x7fc/0x844)
[<c023e170>] (sctp_outq_flush+0x0/0x844) from [<c023ef78>] (sctp_outq_uncork+0x24/0x28)
[<c023ef54>] (sctp_outq_uncork+0x0/0x28) from [<c0234364>] (sctp_side_effects+0x1134/0x1220)
[<c0233230>] (sctp_side_effects+0x0/0x1220) from [<c02330b0>] (sctp_do_sm+0xac/0xd4)
[<c0233004>] (sctp_do_sm+0x0/0xd4) from [<c023675c>] (sctp_assoc_bh_rcv+0x118/0x160)
[<c0236644>] (sctp_assoc_bh_rcv+0x0/0x160) from [<c023d5bc>] (sctp_inq_push+0x6c/0x74)
[<c023d550>] (sctp_inq_push+0x0/0x74) from [<c024a6b0>] (sctp_rcv+0x7d8/0x888)
While we already had various kind of bugs in that area ec0223ec48a9 ("net: sctp: fix sctp_sf_do_5_1D_ce to verify if
we/peer is AUTH capable") and b14878ccb7fa ("net: sctp: cache
auth_enable per endpoint"), this one is a bit of a different
kind.
Giving a bit more background on why SCTP authentication is
needed can be found in RFC4895:
SCTP uses 32-bit verification tags to protect itself against
blind attackers. These values are not changed during the
lifetime of an SCTP association.
Looking at new SCTP extensions, there is the need to have a
method of proving that an SCTP chunk(s) was really sent by
the original peer that started the association and not by a
malicious attacker.
To cause this bug, we're triggering an INIT collision between
peers; normal SCTP handshake where both sides intent to
authenticate packets contains RANDOM; CHUNKS; HMAC-ALGO
parameters that are being negotiated among peers:
RFC4895 says that each endpoint therefore knows its own random
number and the peer's random number *after* the association
has been established. The local and peer's random number along
with the shared key are then part of the secret used for
calculating the HMAC in the AUTH chunk.
Now, in our scenario, we have 2 threads with 1 non-blocking
SEQ_PACKET socket each, setting up common shared SCTP_AUTH_KEY
and SCTP_AUTH_ACTIVE_KEY properly, and each of them calling
sctp_bindx(3), listen(2) and connect(2) against each other,
thus the handshake looks similar to this, e.g.:
Since such collisions can also happen with verification tags,
the RFC4895 for AUTH rather vaguely says under section 6.1:
In case of INIT collision, the rules governing the handling
of this Random Number follow the same pattern as those for
the Verification Tag, as explained in Section 5.2.4 of
RFC 2960 [5]. Therefore, each endpoint knows its own Random
Number and the peer's Random Number after the association
has been established.
In RFC2960, section 5.2.4, we're eventually hitting Action B:
B) In this case, both sides may be attempting to start an
association at about the same time but the peer endpoint
started its INIT after responding to the local endpoint's
INIT. Thus it may have picked a new Verification Tag not
being aware of the previous Tag it had sent this endpoint.
The endpoint should stay in or enter the ESTABLISHED
state but it MUST update its peer's Verification Tag from
the State Cookie, stop any init or cookie timers that may
running and send a COOKIE ACK.
In other words, the handling of the Random parameter is the
same as behavior for the Verification Tag as described in
Action B of section 5.2.4.
Looking at the code, we exactly hit the sctp_sf_do_dupcook_b()
case which triggers an SCTP_CMD_UPDATE_ASSOC command to the
side effect interpreter, and in fact it properly copies over
peer_{random, hmacs, chunks} parameters from the newly created
association to update the existing one.
Also, the old asoc_shared_key is being released and based on
the new params, sctp_auth_asoc_init_active_key() updated.
However, the issue observed in this case is that the previous
asoc->peer.auth_capable was 0, and has *not* been updated, so
that instead of creating a new secret, we're doing an early
return from the function sctp_auth_asoc_init_active_key()
leaving asoc->asoc_shared_key as NULL. However, we now have to
authenticate chunks from the updated chunk list (e.g. COOKIE-ACK).
That in fact causes the server side when responding with ...
... to trigger a NULL pointer dereference, since in
sctp_packet_transmit(), it discovers that an AUTH chunk is
being queued for xmit, and thus it calls sctp_auth_calculate_hmac().
Since the asoc->active_key_id is still inherited from the
endpoint, and the same as encoded into the chunk, it uses
asoc->asoc_shared_key, which is still NULL, as an asoc_key
and dereferences it in ...
... causing an oops. All this happens because sctp_make_cookie_ack()
called with the *new* association has the peer.auth_capable=1
and therefore marks the chunk with auth=1 after checking
sctp_auth_send_cid(), but it is *actually* sent later on over
the then *updated* association's transport that didn't initialize
its shared key due to peer.auth_capable=0. Since control chunks
in that case are not sent by the temporary association which
are scheduled for deletion, they are issued for xmit via
SCTP_CMD_REPLY in the interpreter with the context of the
*updated* association. peer.auth_capable was 0 in the updated
association (which went from COOKIE_WAIT into ESTABLISHED state),
since all previous processing that performed sctp_process_init()
was being done on temporary associations, that we eventually
throw away each time.
The correct fix is to update to the new peer.auth_capable
value as well in the collision case via sctp_assoc_update(),
so that in case the collision migrated from 0 -> 1,
sctp_auth_asoc_init_active_key() can properly recalculate
the secret. This therefore fixes the observed server panic.
Fixes: 730fc3d05cd4 ("[SCTP]: Implete SCTP-AUTH parameter processing") Reported-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Tested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Cc: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
In vegas we do a multiplication of the cwnd and the rtt. This
may overflow and thus their result is stored in a u64. However, we first
need to cast the cwnd so that actually 64-bit arithmetic is done.
Then, we need to do do_div to allow this to be used on 32-bit arches.
Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Neal Cardwell <ncardwell@google.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Laight <David.Laight@ACULAB.COM> Cc: Doug Leith <doug.leith@nuim.ie> Fixes: 8d3a564da34e (tcp: tcp_vegas cong avoid fix) Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
In veno we do a multiplication of the cwnd and the rtt. This
may overflow and thus their result is stored in a u64. However, we first
need to cast the cwnd so that actually 64-bit arithmetic is done.
A first attempt at fixing 76f1017757aa0 ([TCP]: TCP Veno congestion
control) was made by 159131149c2 (tcp: Overflow bug in Vegas), but it
failed to add the required cast in tcp_veno_cong_avoid().
Fixes: 76f1017757aa0 ([TCP]: TCP Veno congestion control) Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
In "Counting Packets Sent Between Arbitrary Internet Hosts", Jeffrey and
Jedidiah describe ways exploiting linux IP identifier generation to
infer whether two machines are exchanging packets.
With commit 73f156a6e8c1 ("inetpeer: get rid of ip_id_count"), we
changed IP id generation, but this does not really prevent this
side-channel technique.
This patch adds a random amount of perturbation so that IP identifiers
for a given destination [1] are no longer monotonically increasing after
an idle period.
Note that prandom_u32_max(1) returns 0, so if generator is used at most
once per jiffy, this patch inserts no hole in the ID suite and do not
increase collision probability.
This is jiffies based, so in the worst case (HZ=1000), the id can
rollover after ~65 seconds of idle time, which should be fine.
We also change the hash used in __ip_select_ident() to not only hash
on daddr, but also saddr and protocol, so that ICMP probes can not be
used to infer information for other protocols.
For IPv6, adds saddr into the hash as well, but not nexthdr.
If I ping the patched target, we can see ID are now hard to predict.
21:57:11.008086 IP (...)
A > target: ICMP echo request, seq 1, length 64
21:57:11.010752 IP (... id 2081 ...)
target > A: ICMP echo reply, seq 1, length 64
21:57:12.013133 IP (...)
A > target: ICMP echo request, seq 2, length 64
21:57:12.015737 IP (... id 3039 ...)
target > A: ICMP echo reply, seq 2, length 64
21:57:13.016580 IP (...)
A > target: ICMP echo request, seq 3, length 64
21:57:13.019251 IP (... id 3437 ...)
target > A: ICMP echo reply, seq 3, length 64
[1] TCP sessions uses a per flow ID generator not changed by this patch.
Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jeffrey Knockel <jeffk@cs.unm.edu> Reported-by: Jedidiah R. Crandall <crandall@cs.unm.edu> Cc: Willy Tarreau <w@1wt.eu> Cc: Hannes Frederic Sowa <hannes@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Ideally, we would need to generate IP ID using a per destination IP
generator.
linux kernels used inet_peer cache for this purpose, but this had a huge
cost on servers disabling MTU discovery.
1) each inet_peer struct consumes 192 bytes
2) inetpeer cache uses a binary tree of inet_peer structs,
with a nominal size of ~66000 elements under load.
3) lookups in this tree are hitting a lot of cache lines, as tree depth
is about 20.
4) If server deals with many tcp flows, we have a high probability of
not finding the inet_peer, allocating a fresh one, inserting it in
the tree with same initial ip_id_count, (cf secure_ip_id())
5) We garbage collect inet_peer aggressively.
IP ID generation do not have to be 'perfect'
Goal is trying to avoid duplicates in a short period of time,
so that reassembly units have a chance to complete reassembly of
fragments belonging to one message before receiving other fragments
with a recycled ID.
We simply use an array of generators, and a Jenkin hash using the dst IP
as a key.
ipv6_select_ident() is put back into net/ipv6/ip6_output.c where it
belongs (it is only used from this file)
secure_ip_id() and secure_ipv6_id() no longer are needed.
Rename ip_select_ident_more() to ip_select_ident_segs() to avoid
unnecessary decrement/increment of the number of segments.
Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Caches in most systems are identical - but not always, so we can't avoid
the use of smp_call_function() by just looking at the boot CPU's data,
have to fiddle with preemption instead.
cc1: warnings being treated as errors
arch/mips/kernel/perf_event_mipsxx.c:166: error: 'counters_per_cpu_to_total' defined but not used
make[2]: *** [arch/mips/kernel/perf_event_mipsxx.o] Error 1
make[2]: *** Waiting for unfinished jobs....
Reported-by: Jack Thomasson <jkt@moonlitsw.com> Tested-by: Christian Svensson <blue@cmd.nu> Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Signed-off-by: Jonas Bonn <jonas@southpole.se> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Make sure to verify the number of ports requested by subdriver to avoid
writing beyond the end of fixed-size array in interface data.
The current usb-serial implementation is limited to eight ports per
interface but failed to verify that the number of ports requested by a
subdriver (which could have been determined from device descriptors) did
not exceed this limit.
Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: s/ddev/\&interface->dev/] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Make sure to verify the maximum number of endpoints per type to avoid
writing beyond the end of a stack-allocated array.
The current usb-serial implementation is limited to eight ports per
interface but failed to verify that the number of endpoints of a certain
type reported by a device did not exceed this limit.
Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
On revisions of Cortex-A15 prior to r3p3, a CLREX instruction at PL1 may
falsely trigger a watchpoint exception, leading to potential data aborts
during exception return and/or livelock.
This patch resolves the issue in the following ways:
- Replacing our uses of CLREX with a dummy STREX sequence instead (as
we did for v6 CPUs).
- Removing the clrex code from v7_exit_coherency_flush and derivatives,
since this only exists as a minor performance improvement when
non-cached exclusives are in use (Linux doesn't use these).
Benchmarking on a variety of ARM cores revealed no measurable
performance difference with this change applied, so the change is
performed unconditionally and no new Kconfig entry is added.
Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[bwh: Backported to 3.2:
- Drop inapplicable changes to arch/arm/include/asm/cacheflush.h and
arch/arm/mach-exynos/mcpm-exynos.c] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The ARMv6 and ARMv7 early abort handlers clear the exclusive monitors
upon entry to the kernel, but this is redundant:
- We clear the monitors on every exception return since commit 200b812d0084 ("Clear the exclusive monitor when returning from an
exception"), so this is not necessary to ensure the monitors are
cleared before returning from a fault handler.
- Any dummy STREX will target a temporary scratch area in memory, and
may succeed or fail without corrupting useful data. Its status value
will not be used.
- Any other STREX in the kernel must be preceded by an LDREX, which
will initialise the monitors consistently and will not depend on the
earlier state of the monitors.
Therefore we have no reason to care about the initial state of the
exclusive monitors when a data abort is taken, and clearing the monitors
prior to exception return (as we already do) is sufficient.
This patch removes the redundant clearing of the exclusive monitors from
the early abort handlers.
Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The report passed to us from transport driver could potentially be
arbitrarily large, therefore we better sanity-check it so that raw_data
that we hold in picolcd_pending structure are always kept within proper
bounds.
Reported-by: Steven Vittitoe <scvitti@google.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
[bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The report passed to us from transport driver could potentially be
arbitrarily large, therefore we better sanity-check it so that
magicmouse_emit_touch() gets only valid values of raw_id.
Reported-by: Steven Vittitoe <scvitti@google.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
In the presence of delegations, we can no longer assume that the
state->n_rdwr, state->n_rdonly, state->n_wronly reflect the open
stateid share mode, and so we need to calculate the initial value
for calldata->arg.fmode using the state->flags.
Reported-by: James Drews <drews@engr.wisc.edu> Fixes: 88069f77e1ac5 (NFSv41: Fix a potential state leakage when...) Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
There is a platform refusing to respond QR_EC when SCI_EVT isn't set
(Acer Aspire V5-573G).
Currently, we rely on the behaviour that the EC firmware can respond
something (for example, 0x00 to indicate "no outstanding events") to
QR_EC even when SCI_EVT is not set, but the reporter has complained
about AC/battery pluging/unpluging and video brightness change delay
on that platform.
This is because the work item that has issued QR_EC has to wait until
timeout in this case, and the _Qxx method evaluation work item queued
after QR_EC one is delayed.
It sounds reasonable to fix this issue by:
1. Implementing SCI_EVT sanity check before issuing QR_EC in the EC
driver's main state machine.
2. Moving QR_EC issuing out of the work queue used by _Qxx evaluation
to a seperate IRQ handling thread.
This patch fixes this issue using solution 1.
By disallowing QR_EC to be issued when SCI_EVT isn't set, we are able to
handle such platform in the EC driver's main state machine. This patch
enhances the state machine in this way to survive with such malfunctioning
EC firmware.
Note that this patch can also fix CLEAR_ON_RESUME quirk which also relies
on the assumption that the platforms are able to respond even when SCI_EVT
isn't set.
Fixes: c0d653412fc8 ACPI / EC: Fix race condition in ec_transaction_completed() Link: https://bugzilla.kernel.org/show_bug.cgi?id=82611 Reported-and-tested-by: Alexander Mezin <mezin.alexander@gmail.com> Signed-off-by: Lv Zheng <lv.zheng@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Commit "HID: logitech: perform bounds checking on device_id early
enough" unfortunately leaks some errors to dmesg which are not real
ones:
- if the report is not a DJ one, then there is not point in checking
the device_id
- the receiver (index 0) can also receive some notifications which
can be safely ignored given the current implementation
Move out the test regarding the report_id and also discards
printing errors when the receiver got notified.
Fixes: ad3e14d7c5268c2e24477c6ef54bbdf88add5d36 Reported-and-tested-by: Markus Trippelsdorf <markus@trippelsdorf.de> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This patch fixes a potential security issue in the whiteheat USB driver
which might allow a local attacker to cause kernel memory corrpution. This
is due to an unchecked memcpy into a fixed size buffer (of 64 bytes). On
EHCI and XHCI busses it's possible to craft responses greater than 64
bytes leading a buffer overflow.
Signed-off-by: James Forshaw <forshaw@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
device_index is a char type and the size of paired_dj_deivces is 7
elements, therefore proper bounds checking has to be applied to
device_index before it is used.
We are currently performing the bounds checking in
logi_dj_recv_add_djhid_device(), which is too late, as malicious device
could send REPORT_TYPE_NOTIF_DEVICE_UNPAIRED early enough and trigger the
problem in one of the report forwarding functions called from
logi_dj_raw_event().
Fix this by performing the check at the earliest possible ocasion in
logi_dj_raw_event().
Reported-by: Ben Hawkes <hawkes@google.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
We did not check relocated directory in any way when processing Rock
Ridge 'CL' tag. Thus a corrupted isofs image can possibly have a CL
entry pointing to another CL entry leading to possibly unbounded
recursion in kernel code and thus stack overflow or deadlocks (if there
is a loop created from CL entries).
Fix the problem by not allowing CL entry to point to a directory entry
with CL entry (such use makes no good sense anyway) and by checking
whether CL entry doesn't point to itself.
Reported-by: Chris Evans <cevans@google.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When we manually need to move the TR dequeue pointer we need to set the
correct cycle bit as well. Previously we used the trb pointer from the
last event received as a base, but this was changed in
commit 1f81b6d22a59 ("usb: xhci: Prefer endpoint context dequeue pointer")
to use the dequeue pointer from the endpoint context instead
It turns out some Asmedia controllers advance the dequeue pointer
stored in the endpoint context past the event triggering TRB, and
this messed up the way the cycle bit was calculated.
Instead of adding a quirk or complicating the already hard to follow cycle bit
code, the whole cycle bit calculation is now simplified and adapted to handle
event and endpoint context dequeue pointer differences.
Fixes: 1f81b6d22a59 ("usb: xhci: Prefer endpoint context dequeue pointer") Reported-by: Maciej Puzio <mx34567@gmail.com> Reported-by: Evan Langlois <uudruid74@gmail.com> Reviewed-by: Julius Werner <jwerner@chromium.org> Tested-by: Maciej Puzio <mx34567@gmail.com> Tested-by: Evan Langlois <uudruid74@gmail.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2:
- Debug logging in xhci_find_new_dequeue_state() is slightly different
- Don't delete find_trb_seg(); it's still needed by xhci_cmd_to_noop()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
get_system_type() is not thread-safe on OCTEON. It uses static data,
also more dangerous issue is that it's calling cvmx_fuse_read_byte()
every time without any synchronization. Currently it's possible to get
processes stuck looping forever in kernel simply by launching multiple
readers of /proc/cpuinfo:
(while true; do cat /proc/cpuinfo > /dev/null; done) &
(while true; do cat /proc/cpuinfo > /dev/null; done) &
...
Fix by initializing the system type string only once during the early
boot.
Signed-off-by: Aaro Koskinen <aaro.koskinen@nsn.com> Reviewed-by: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: http://patchwork.linux-mips.org/patch/7437/ Signed-off-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
AMD xHC also needs short tx quirk after tested on most of chipset
generations. That's because there is the same incorrect behavior like
Fresco Logic host. Please see below message with on USB webcam
attached on xHC host:
[ 139.262944] xhci_hcd 0000:00:10.0: WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk?
[ 139.266934] xhci_hcd 0000:00:10.0: WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk?
[ 139.270913] xhci_hcd 0000:00:10.0: WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk?
[ 139.274937] xhci_hcd 0000:00:10.0: WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk?
[ 139.278914] xhci_hcd 0000:00:10.0: WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk?
[ 139.282936] xhci_hcd 0000:00:10.0: WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk?
[ 139.286915] xhci_hcd 0000:00:10.0: WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk?
[ 139.290938] xhci_hcd 0000:00:10.0: WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk?
[ 139.294913] xhci_hcd 0000:00:10.0: WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk?
[ 139.298917] xhci_hcd 0000:00:10.0: WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk?
Reported-by: Arindam Nath <arindam.nath@amd.com> Tested-by: Shriraj-Rai P <shriraj-rai.p@amd.com> Signed-off-by: Huang Rui <ray.huang@amd.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When using a Renesas uPD720231 chipset usb-3 uas to sata bridge with a 120G
Crucial M500 ssd, model string: Crucial_ CT120M500SSD1, together with a
the integrated Intel xhci controller on a Haswell laptop:
00:14.0 USB controller [0c03]: Intel Corporation 8 Series USB xHCI HC [8086:9c31] (rev 04)
The following error gets logged to dmesg:
xhci error: Transfer event TRB DMA ptr not part of current TD
Treating COMP_STOP the same as COMP_STOP_INVAL when no event_seg gets found
fixes this.
Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The third parameter of kvm_iommu_put_pages is wrong,
It should be 'gfn - slot->base_gfn'.
By making gfn very large, malicious guest or userspace can cause kvm to
go to this error path, and subsequently to pass a huge value as size.
Alternatively if gfn is small, then pages would be pinned but never
unpinned, causing host memory leak and local DOS.
Passing a reasonable but large value could be the most dangerous case,
because it would unpin a page that should have stayed pinned, and thus
allow the device to DMA into arbitrary memory. However, this cannot
happen because of the condition that can trigger the error:
- out of memory (where you can't allocate even a single page)
should not be possible for the attacker to trigger
- when exceeding the iommu's address space, guest pages after gfn
will also exceed the iommu's address space, and inside
kvm_iommu_put_pages() the iommu_iova_to_phys() will fail. The
page thus would not be unpinned at all.
Reported-by: Jack Morgenstein <jackm@mellanox.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When multiple devices are detached in __detach_device, they
are also removed from the domains dev_list. This makes it
unsafe to use list_for_each_entry_safe, as the next pointer
might also not be in the list anymore after __detach_device
returns. So just repeatedly remove the first element of the
list until it is empty.
Add device id for Basic Micro ATOM Nano USB2Serial adapters.
Reported-by: Nicolas Alt <n.alt@mytum.de> Tested-by: Nicolas Alt <n.alt@mytum.de> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
During recovery of a double-degraded RAID6 it is possible for
some blocks not to be recovered properly, leading to corruption.
If a write happens to one block in a stripe that would be written to a
missing device, and at the same time that stripe is recovering data
to the other missing device, then that recovered data may not be written.
This patch skips, in the double-degraded case, an optimisation that is
only safe for single-degraded arrays.
Bug was introduced in 2.6.32 and fix is suitable for any kernel since
then. In an older kernel with separate handle_stripe5() and
handle_stripe6() functions the patch must change handle_stripe6().
Fixes: 6c0069c0ae9659e3a91b68eaed06a5c6c37f45c8 Cc: Yuri Tikhonov <yur@emcraft.com> Cc: Dan Williams <dan.j.williams@intel.com> Reported-by: "Manibalan P" <pmanibalan@amiindia.co.in> Tested-by: "Manibalan P" <pmanibalan@amiindia.co.in>
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1090423 Signed-off-by: NeilBrown <neilb@suse.de> Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When we requests rename we also need to update attributes
of both source and target parent directories. Not doing it
causes generic/309 xfstest to fail on SMB2 mounts. Fix this
by marking these directories for force revalidating.
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org> Signed-off-by: Steve French <smfrench@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ALC269 & co have many vendor-specific setups with COEF verbs.
However, some verbs seem specific to some codec versions and they
result in the codec stalling. Typically, such a case can be avoided
by checking the return value from reading a COEF. If the return value
is -1, it implies that the COEF is invalid, thus it shouldn't be
written.
This patch adds the invalid COEF checks in appropriate places
accessing ALC269 and its variants. The patch actually fixes the
resume problem on Acer AO725 laptop.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=52181 Tested-by: Francesco Muzio <muziofg@gmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Under rare circumstances we can end up leaving 2 versions of a checksum
for the same file extent range.
The reason for this is that after calling btrfs_next_leaf we process
slot 0 of the leaf it returns, instead of processing the slot set in
path->slots[0]. Most of the time (by far) path->slots[0] is 0, but after
btrfs_next_leaf() releases the path and before it searches for the next
leaf, another task might cause a split of the next leaf, which migrates
some of its keys to the leaf we were processing before calling
btrfs_next_leaf(). In this case btrfs_next_leaf() returns again the
same leaf but with path->slots[0] having a slot number corresponding
to the first new key it got, that is, a slot number that didn't exist
before calling btrfs_next_leaf(), as the leaf now has more keys than
it had before. So we must really process the returned leaf starting at
path->slots[0] always, as it isn't always 0, and the key at slot 0 can
have an offset much lower than our search offset/bytenr.
For example, consider the following scenario, where we have:
Because we are at the last slot of leaf N, we call btrfs_next_leaf() to
find the next highest key, which releases the current path and then searches
for that next key. However after releasing the path and before finding that
next key, the item at slot 0 of leaf N + 1 gets moved to leaf N, due to a call
to ctree.c:push_leaf_left() (via ctree.c:split_leaf()), and therefore
btrfs_next_leaf() will returns us a path again with leaf N but with the slot
pointing to its new last key (CSUM CSUM 40161280). This new version of leaf N
is then:
In other words, we insert a new csum item in the tree with key
(CSUM_OBJECTID CSUM_KEY 40157184 = sums->bytenr) that contains the checksums
for all the data (4 blocks of 4096 bytes each = sums->len). Which is wrong,
because the item with key (CSUM CSUM 40161280) (the one that was moved from
leaf N + 1 to the end of leaf N) contains the old checksums of the last 12288
bytes of our data and won't get those old checksums removed.
So this leaves us 2 different checksums for 3 4kb blocks of data in the tree,
and breaks the logical rule:
An obvious bad effect of this is that a subsequent csum tree lookup to get
the checksum of any of the blocks with logical offset of 40161280, 40165376
or 40169472 (the last 3 4kb blocks of file data), will get the old checksums.
Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This mode is unsupported, as the DMA controller can't do zero-padding
of samples.
Signed-off-by: Daniel Mack <zonque@gmail.com> Reported-by: Johannes Stezenbach <js@sig21.net> Signed-off-by: Mark Brown <broonie@linaro.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
On ppc64 we support 4K hash pte with 64K page size. That requires
us to track the hash pte slot information on a per 4k basis. We do that
by storing the slot details in the second half of pte page. The pte bit
_PAGE_COMBO is used to indicate whether the second half need to be
looked while building real_pte. We need to use read memory barrier while
doing that so that load of hidx is not reordered w.r.t _PAGE_COMBO
check. On the store side we already do a lwsync in __hash_page_4K
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[bwh: Backported to 3.2: include <asm/system.h> to ensure smp_rmb()
is defined; cell_defconfig fails to build without this] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If do_journal_release() races with do_journal_end() which requeues
delayed works for transaction flushing, we can leave work items for
flushing outstanding transactions queued while freeing them. That
results in use after free and possible crash in run_timers_softirq().
Fix the problem by not requeueing works if superblock is being shut down
(MS_ACTIVE not set) and using cancel_delayed_work_sync() in
do_journal_release().
Signed-off-by: Jan Kara <jack@suse.cz>
[bwh: Backported to 3.2:
- Adjust context
- commit_wq is global, not per-superblock
- Change comment about 'these works'; we only have one work item
- Drop inapplicable changes to reiserfs_schedule_old_flush()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The driver assumes that endpoint 4 is always an interrupt endpoint.
Unfortunately the type differs between high-speed and full-speed
configurations while in the former case it is indeed an interrupt
endpoint this is not true for the latter case - here it is a bulk
endpoint. When sending URBs with the wrong type the kernel will
generate a warning message including backtrace. In this specific
case there will be a huge amount of warnings which can bring the system
to freeze.
To fix this we are now sending URBs to endpoint 4 using the type
found in the endpoint descriptor.
A side note: The carl9170 firmware currently specifies endpoint 4 as
interrupt endpoint even in the full-speed configuration but this has
no relevance because before this firmware is loaded the endpoint type
is as described above and after the firmware is running the stick is not
reenumerated and so the old descriptor is used.
Signed-off-by: Ronald Wahl <ronald.wahl@raritan.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If the timer irqs are resumed during device resume it is possible in
certain circumstances for the resume to hang early on, before device
interrupts are resumed. For an Ubuntu 14.04 PVHVM guest this would
occur in ~0.5% of resume attempts.
It is not entirely clear what is occuring the point of the hang but I
think a task necessary for the resume calls schedule_timeout(),
waiting for a timer interrupt (which never arrives). This failure may
require specific tasks to be running on the other VCPUs to trigger
(processes are not frozen during a suspend/resume if PREEMPT is
disabled).
Add IRQF_EARLY_RESUME to the timer interrupts so they are resumed in
syscore_resume().
Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
When performing a consuming read, the ring buffer swaps out a
page from the ring buffer with a empty page and this page that
was swapped out becomes the new reader page. The reader page
is owned by the reader and since it was swapped out of the ring
buffer, writers do not have access to it (there's an exception
to that rule, but it's out of scope for this commit).
When reading the "trace" file, it is a non consuming read, which
means that the data in the ring buffer will not be modified.
When the trace file is opened, a ring buffer iterator is allocated
and writes to the ring buffer are disabled, such that the iterator
will not have issues iterating over the data.
Although the ring buffer disabled writes, it does not disable other
reads, or even consuming reads. If a consuming read happens, then
the iterator is reset and starts reading from the beginning again.
My tests would sometimes trigger this bug on my i386 box:
Which was the __trace_find_cmdline() function complaining about the pid
in the event record being negative.
After adding more test cases, this would trigger more often. Strangely
enough, it would never trigger on a single test, but instead would trigger
only when running all the tests. I believe that was the case because it
required one of the tests to be shutting down via delayed instances while
a new test started up.
After spending several days debugging this, I found that it was caused by
the iterator becoming corrupted. Debugging further, I found out why
the iterator became corrupted. It happened with the rb_iter_reset().
As consuming reads may not read the full reader page, and only part
of it, there's a "read" field to know where the last read took place.
The iterator, must also start at the read position. In the rb_iter_reset()
code, if the reader page was disconnected from the ring buffer, the iterator
would start at the head page within the ring buffer (where writes still
happen). But the mistake there was that it still used the "read" field
to start the iterator on the head page, where it should always start
at zero because readers never read from within the ring buffer where
writes occur.
I originally wrote a patch to have it set the iter->head to 0 instead
of iter->head_page->read, but then I questioned why it wasn't always
setting the iter to point to the reader page, as the reader page is
still valid. The list_empty(reader_page->list) just means that it was
successful in swapping out. But the reader_page may still have data.
There was a bug report a long time ago that was not reproducible that
had something about trace_pipe (consuming read) not matching trace
(iterator read). This may explain why that happened.
Anyway, the correct answer to this bug is to always use the reader page
an not reset the iterator to inside the writable ring buffer.
Fixes: d769041f8653 "ring_buffer: implement new locking" Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Debugging this bug, which triggers when the rb_iter_peek() loops too
many times (more than 2 times), I discovered there's a case that can
cause that function to legitimately loop 3 times!
rb_iter_peek() is different than rb_buffer_peek() as the rb_buffer_peek()
only deals with the reader page (it's for consuming reads). The
rb_iter_peek() is for traversing the buffer without consuming it, and as
such, it can loop for one more reason. That is, if we hit the end of
the reader page or any page, it will go to the next page and try again.
That is, we have this:
1. iter->head > iter->head_page->page->commit
(rb_inc_iter() which moves the iter to the next page)
try again
2. event = rb_iter_head_event()
event->type_len == RINGBUF_TYPE_TIME_EXTEND
rb_advance_iter()
try again
3. read the event.
But we never get to 3, because the count is greater than 2 and we
cause the WARNING and return NULL.
Up the counter to 3.
Fixes: 69d1b839f7ee "ring-buffer: Bind time extend and data events together" Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
[bwh: Backported to 3.2: drop inapplicable spelling correction] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
commit 4badad352a6bb202ec68afa7a574c0bb961e5ebc (locking/mutex: Disable
optimistic spinning on some architectures) fenced spinning for
architectures without proper cmpxchg.
There is no need to disable mutex spinning on s390, though:
The instructions CS,CSG and friends provide the proper guarantees.
(We dont implement cmpxchg with locks).
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Current code uses data_rate as array index in ads1015_read_adc() and uses pga
as array index in ads1015_reg_to_mv, so we must make sure both data_rate and
pga settings are in valid value range.
Return -EINVAL if the setting is out-of-range.
Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
On platforms with sizeof(int) < sizeof(long), writing a temperature
limit larger than MAXINT will result in unpredictable limit values
written to the chip. Avoid auto-conversion from long to int to fix
the problem.
The hysteresis temperature range depends on the value of
data->temp[attr->index], since val is subtracted from it.
Use a wider clamp, [-120000, 220000] should do to cover the
possible range. Also add missing TEMP_TO_REG() on writes into
cached hysteresis value.
Also uses clamp_val to simplify the code a bit.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
[Guenter Roeck: Fixed double TEMP_TO_REG on hysteresis updates] Signed-off-by: Guenter Roeck <linux@roeck-us.net>
[bwh: Backported to 3.2:
- s/temp\[attr->index\]/temp1_crit/
- s/temp\[t_hyst\]/temp1_hyst/] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If the user creates a listening cm_id with backlog of 0 the IWCM ends
up not allowing any connection requests at all. The correct behavior
is for the IWCM to pick a default value if the user backlog parameter
is zero.
Lustre from version 1.8.8 onward uses a backlog of 0, which breaks
iwarp support without this fix.
Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Roland Dreier <roland@purestorage.com>
[bwh: Backported to 3.2: use register_net_sysctl_table()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
While ttm_dma_pool_shrink_scan() tries to take mutex before doing GFP_KERNEL
allocation, ttm_pool_shrink_scan() does not do it. This can result in stack
overflow if kmalloc() in ttm_page_pool_free() triggered recursion due to
memory pressure.
Change ttm_pool_shrink_scan() to do like ttm_dma_pool_shrink_scan() does.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Dave Airlie <airlied@redhat.com>
[bwh: Backported to 3.2:
- Adjust context
- Change return value in the contended case to follow the old shrinker
API] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
On platforms with sizeof(int) < sizeof(long), writing a temperature
limit larger than MAXINT will result in unpredictable limit values
written to the chip. Avoid auto-conversion from long to int to fix
the problem.
Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
On platforms with sizeof(int) < sizeof(unsigned long), writing a rpm value
larger than MAXINT will result in unpredictable limit values written to the
chip. Avoid auto-conversion from unsigned long to int to fix the problem.
Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This patch adds support for ASUS - Xonar DSX sound cards. Tested on
openSUSE 12.2 with kernel:
Linux 3.4.6-2.10-desktop #1 SMP PREEMPT Thu Jul 26 09:36:26 UTC 2012 (641c197) x86_64 x86_64 x86_64 GNU/Linux
Works:
- play sounds
- adjust volume on master channel.
- mute .
Since Xonar DS uses the same chip, everything that works for DS should
work for DSX as well.
This adds support for new Xsens devices, using Xsens' own Vendor ID.
Signed-off-by: Patrick Riphagen <patrick.riphagen@xsens.com> Signed-off-by: Frans Klaver <frans.klaver@xsens.com> Cc: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The converters are used in specific products. It can be useful to know
which they are exactly.
Signed-off-by: Patrick Riphagen <patrick.riphagen@xsens.com> Signed-off-by: Frans Klaver <frans.klaver@xsens.com> Cc: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
The NetLabel category (catmap) functions have a problem in that they
assume categories will be set in an increasing manner, e.g. the next
category set will always be larger than the last. Unfortunately, this
is not a valid assumption and could result in problems when attempting
to set categories less than the startbit in the lowest catmap node.
In some cases kernel panics and other nasties can result.
This patch corrects the problem by checking for this and allocating a
new catmap node instance and placing it at the front of the list.
Reported-by: Christian Evans <frodox@zoho.com> Signed-off-by: Paul Moore <pmoore@redhat.com> Tested-by: Casey Schaufler <casey@schaufler-ca.com>
[bwh: Backported to 3.2: adjust filename for SMACK] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
This function takes a GFP flags as a parameter, but they are never used.
We don't take a lock in this function so there is no reason to prefer
GFP_ATOMIC over the caller's GFP flags.
There is only one caller, cipso_v4_map_cat_rng_ntoh(), and it passes
GFP_ATOMIC as the GFP flags so this doesn't change how the code works.
It's just a cleanup.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
According to the comment “restore_es3: applies to 34xx >= ES3.0" in
"arch/arm/mach-omap2/sleep34xx.S”, omap3_restore_es3 should be used
if the revision of an OMAP34xx is ES3.1.2.
Signed-off-by: Jeremy Vial <jvial@adeneo-embedded.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Since March 2009 the kernel has treated the state that if no
MS_..ATIME flags are passed then the kernel defaults to relatime.
Defaulting to relatime instead of the existing atime state during a
remount is silly, and causes problems in practice for people who don't
specify any MS_...ATIME flags and to get the default filesystem atime
setting. Those users may encounter a permission error because the
default atime setting does not work.
A default that does not work and causes permission problems is
ridiculous, so preserve the existing value to have a default
atime setting that is always guaranteed to work.
Using the default atime setting in this way is particularly
interesting for applications built to run in restricted userspace
environments without /proc mounted, as the existing atime mount
options of a filesystem can not be read from /proc/mounts.
In practice this fixes user space that uses the default atime
setting on remount that are broken by the permission checks
keeping less privileged users from changing more privileged users
atime settings.
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
[bwh: Backported to 3.2: add definition of MNT_ATIME_MASK, as we don't
need the fix that introduced that definition upstream] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Th AF_ALG socket was missing a security label (e.g. SELinux)
which means that socket was in "unlabeled" state.
This was recently demonstrated in the cryptsetup package
(cryptsetup v1.6.5 and later.)
See https://bugzilla.redhat.com/show_bug.cgi?id=1115120
This patch clones the sock's label from the parent sock
and resolves the issue (similar to AF_BLUETOOTH protocol family).
Signed-off-by: Milan Broz <gmazyland@gmail.com> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
A GIC interrupt which is declared as having a GIC_MAP_TO_NMI_MSK
mapping causes the cpu parameter to gic_setup_intr() to be increased
to 32, causing memory corruption when pcpu_masks[] is written to again
later in the function.
Ensure mutex lock protects the read-modify-write period to prevent possible
race condition bug.
In additional, update data->valid should also be protected by the mutex lock.
Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
On platforms with sizeof(int) < sizeof(long), writing a temperature
limit larger than MAXINT will result in unpredictable limit values
written to the chip. Avoid auto-conversion from long to int to fix
the problem.
Cc: Axel Lin <axel.lin@ingics.com> Reviewed-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
[bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Temperature limit register writes did not account for negative numbers.
As a result, writing -127000 resulted in -126000 written into the
temperature limit register. This problem affected temp[1-3]_min,
temp[1-3]_max, temp[1-3]_auto_temp_crit, and temp[1-3]_auto_temp_min.
When writing pwm[1-3]_freq, a long variable was auto-converted into an int
without range check. Wiring values larger than MAXINT resulted in unexpected
register values.
When writing temp[1-3]_auto_temp_max, an unsigned long variable was
auto-converted into an int without range check. Writing values larger than
MAXINT resulted in unexpected register values.
vrm is an u8, so the written value needs to be limited to [0, 255].
Cc: Axel Lin <axel.lin@ingics.com> Reviewed-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
[bwh: Backported to 3.2:
- Driver is not using clamp_val(); keep using SENSORS_LIMIT() for consistency
- Driver is not using kstrtoul(); make the minimum change to store_vrm_reg()
so we can validate the value before assigning] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
If there is a failure while allocating the preallocation structure, a
number of blocks can end up getting marked in the in-memory buddy
bitmap, and then not getting released. This can result in the
following corruption getting reported by the kernel:
EXT4-fs error (device sda3): ext4_mb_generate_buddy:758: group 1126,
12793 clusters in bitmap, 12729 in gd
In that case, we need to release the blocks using mb_free_blocks().
Tested: fs smoke test; also demonstrated that with injected errors,
the file system is no longer getting corrupted
Currently we don't abort recovery on a write error if the write error
to the recovering device was triggerd by normal IO (as opposed to
recovery IO).
This means that for one bitmap region, the recovery might write to the
recovering device for a few sectors, then not bother for subsequent
sectors (as it never writes to failed devices). In this case
the bitmap bit will be cleared, but it really shouldn't.
The result is that if the recovering device fails and is then re-added
(after fixing whatever hardware problem triggerred the failure),
the second recovery won't redo the region it was in the middle of,
so some of the device will not be recovered properly.
If we abort the recovery, the region being processes will be cancelled
(bit not cleared) and the whole region will be retried.
As the bug can result in data corruption the patch is suitable for
-stable. For kernels prior to 3.11 there is a conflict in raid10.c
which will require care.