88235 Commits

Author SHA1 Message Date
Shile Zhang
0c199348cf sched/rt: Show the 'sched_rr_timeslice' SCHED_RR timeslice tuning knob in milliseconds
[ Upstream commit 975e155ed8732cb81f55c021c441ae662dd040b5 ]

We added the 'sched_rr_timeslice_ms' SCHED_RR tuning knob in this commit:

  ce0dbbbb30ae ("sched/rt: Add a tuning knob to allow changing SCHED_RR timeslice")

... which name suggests to users that it's in milliseconds, while in reality
it's being set in milliseconds but the result is shown in jiffies.

This is obviously confusing when HZ is not 1000, it makes it appear like the
value set failed, such as HZ=100:

  root# echo 100 > /proc/sys/kernel/sched_rr_timeslice_ms
  root# cat /proc/sys/kernel/sched_rr_timeslice_ms
  10

Fix this to be milliseconds all around.

Signed-off-by: Shile Zhang <shile.zhang@nokia.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1485612049-20923-1-git-send-email-shile.zhang@nokia.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-07-09 09:35:55 +02:00
Herbert Xu
04d462a6f4 crypto: af_alg - fix use-after-free in af_alg_accept() due to bh_lock_sock()
commit 34c86f4c4a7be3b3e35aa48bd18299d4c756064d upstream.

The locking in af_alg_release_parent is broken as the BH socket
lock can only be taken if there is a code-path to handle the case
where the lock is owned by process-context.  Instead of adding
such handling, we can fix this by changing the ref counts to
atomic_t.

This patch also modifies the main refcnt to include both normal
and nokey sockets.  This way we don't have to fudge the nokey
ref count when a socket changes from nokey to normal.

Credits go to Mauricio Faria de Oliveira who diagnosed this bug
and sent a patch for it:

https://lore.kernel.org/linux-crypto/20200605161657.535043-1-mfo@canonical.com/

Reported-by: Brian Moyles <bmoyles@netflix.com>
Reported-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Fixes: 37f96694cf73 ("crypto: af_alg - Use bh_lock_sock in...")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-09 09:35:55 +02:00
Alexander Lobakin
ea6eb20cfe net: qed: fix left elements count calculation
[ Upstream commit 97dd1abd026ae4e6a82fa68645928404ad483409 ]

qed_chain_get_element_left{,_u32} returned 0 when the difference
between producer and consumer page count was equal to the total
page count.
Fix this by conditional expanding of producer value (vs
unconditional). This allowed to eliminate normalizaton against
total page count, which was the cause of this bug.

Misc: replace open-coded constants with common defines.

Fixes: a91eb52abb50 ("qed: Revisit chain implementation")
Signed-off-by: Alexander Lobakin <alobakin@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: Michal Kalderon <michal.kalderon@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30 15:38:42 -04:00
Taehee Yoo
6aa66b7153 net: core: reduce recursion limit value
[ Upstream commit fb7861d14c8d7edac65b2fcb6e8031cb138457b2 ]

In the current code, ->ndo_start_xmit() can be executed recursively only
10 times because of stack memory.
But, in the case of the vxlan, 10 recursion limit value results in
a stack overflow.
In the current code, the nested interface is limited by 8 depth.
There is no critical reason that the recursion limitation value should
be 10.
So, it would be good to be the same value with the limitation value of
nesting interface depth.

Test commands:
    ip link add vxlan10 type vxlan vni 10 dstport 4789 srcport 4789 4789
    ip link set vxlan10 up
    ip a a 192.168.10.1/24 dev vxlan10
    ip n a 192.168.10.2 dev vxlan10 lladdr fc:22:33:44:55:66 nud permanent

    for i in {9..0}
    do
        let A=$i+1
	ip link add vxlan$i type vxlan vni $i dstport 4789 srcport 4789 4789
	ip link set vxlan$i up
	ip a a 192.168.$i.1/24 dev vxlan$i
	ip n a 192.168.$i.2 dev vxlan$i lladdr fc:22:33:44:55:66 nud permanent
	bridge fdb add fc:22:33:44:55:66 dev vxlan$A dst 192.168.$i.2 self
    done
    hping3 192.168.10.2 -2 -d 60000

Splat looks like:
[  103.814237][ T1127] =============================================================================
[  103.871955][ T1127] BUG kmalloc-2k (Tainted: G    B            ): Padding overwritten. 0x00000000897a2e4f-0x000
[  103.873187][ T1127] -----------------------------------------------------------------------------
[  103.873187][ T1127]
[  103.874252][ T1127] INFO: Slab 0x000000005cccc724 objects=5 used=5 fp=0x0000000000000000 flags=0x10000000001020
[  103.881323][ T1127] CPU: 3 PID: 1127 Comm: hping3 Tainted: G    B             5.7.0+ #575
[  103.882131][ T1127] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[  103.883006][ T1127] Call Trace:
[  103.883324][ T1127]  dump_stack+0x96/0xdb
[  103.883716][ T1127]  slab_err+0xad/0xd0
[  103.884106][ T1127]  ? _raw_spin_unlock+0x1f/0x30
[  103.884620][ T1127]  ? get_partial_node.isra.78+0x140/0x360
[  103.885214][ T1127]  slab_pad_check.part.53+0xf7/0x160
[  103.885769][ T1127]  ? pskb_expand_head+0x110/0xe10
[  103.886316][ T1127]  check_slab+0x97/0xb0
[  103.886763][ T1127]  alloc_debug_processing+0x84/0x1a0
[  103.887308][ T1127]  ___slab_alloc+0x5a5/0x630
[  103.887765][ T1127]  ? pskb_expand_head+0x110/0xe10
[  103.888265][ T1127]  ? lock_downgrade+0x730/0x730
[  103.888762][ T1127]  ? pskb_expand_head+0x110/0xe10
[  103.889244][ T1127]  ? __slab_alloc+0x3e/0x80
[  103.889675][ T1127]  __slab_alloc+0x3e/0x80
[  103.890108][ T1127]  __kmalloc_node_track_caller+0xc7/0x420
[ ... ]

Fixes: 11a766ce915f ("net: Increase xmit RECURSION_LIMIT to 10.")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30 15:38:39 -04:00
Tariq Toukan
673212158f net: Do not clear the sock TX queue in sk_set_socket()
[ Upstream commit 41b14fb8724d5a4b382a63cb4a1a61880347ccb8 ]

Clearing the sock TX queue in sk_set_socket() might cause unexpected
out-of-order transmit when called from sock_orphan(), as outstanding
packets can pick a different TX queue and bypass the ones already queued.

This is undesired in general. More specifically, it breaks the in-order
scheduling property guarantee for device-offloaded TLS sockets.

Remove the call to sk_tx_queue_clear() in sk_set_socket(), and add it
explicitly only where needed.

Fixes: e022f0b4a03f ("net: Introduce sk_tx_queue_mapping")
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Reviewed-by: Boris Pismenny <borisp@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30 15:38:39 -04:00
Marcelo Ricardo Leitner
5030f66824 sctp: Don't advertise IPv4 addresses if ipv6only is set on the socket
[ Upstream commit 471e39df96b9a4c4ba88a2da9e25a126624d7a9c ]

If a socket is set ipv6only, it will still send IPv4 addresses in the
INIT and INIT_ACK packets. This potentially misleads the peer into using
them, which then would cause association termination.

The fix is to not add IPv4 addresses to ipv6only sockets.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Tested-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30 15:38:39 -04:00
Boris Brezillon
6624691037 mtd: rawnand: Pass a nand_chip object to nand_release()
[ Upstream commit 59ac276f22270fb2094910f9a734c17f41c25e70 ]

Let's make the raw NAND API consistent by patching all helpers to
take a nand_chip object instead of an mtd_info one.

Now is nand_release()'s turn.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30 15:38:36 -04:00
Mauro Carvalho Chehab
55089d34f1 media: dvb_frontend: fix return values for FE_SET_PROPERTY
commit 259a41d9ae8f3689742267f340ad2b159d00b302 upstream

There are several problems with regards to the return of
FE_SET_PROPERTY. The original idea were to return per-property
return codes via tvp->result field, and to return an updated
set of values.

However, that never worked. What's actually implemented is:

- the FE_SET_PROPERTY implementation doesn't call .get_frontend
  callback in order to get the actual parameters after return;

- the tvp->result field is only filled if there's no error.
  So, it is always filled with zero;

- FE_SET_PROPERTY doesn't call memdup_user() nor any other
  copy_to_user() function. So, any changes to the properties
  will be lost;

- FE_SET_PROPERTY is declared as a write-only ioctl (IOW).

While we could fix the above, it could cause regressions.

So, let's just assume what the code really does, updating
the documentation accordingly and removing the logic that
would update the discarded tvp->result.

Reviewed-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30 15:38:35 -04:00
Mauro Carvalho Chehab
dc06ae4f1b media: dvb/frontend.h: document the uAPI file
commit 8220ead805b6bab4ade2839857a198e9708b07de upstream

Most of the stuff at the Digital TV frontend header file
are documented only at the Documentation. However, a few
kernel-doc markups are there, several of them with parsing
issues.

Add the missing documentation, copying definitions from the
Documentation when it applies, fixing some bugs.

Please notice that DVBv3 stuff that were deprecated weren't
commented by purpose. Instead, they were clearly tagged as
such.

This patch prepares to move part of the documentation from
Documentation/ to kernel-doc comments.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30 15:38:33 -04:00
Mauro Carvalho Chehab
fb4ffc2662 media: dvb/frontend.h: move out a private internal structure
commit f35afa4f60c868d7c7811ba747133acbf39410ac upstream

struct dtv_cmds_h is just an ancillary struct used by the
dvb_frontend.c to internally store frontend commands.

It doesn't belong to the userspace header, nor it is used anywhere,
except inside the DVB core. So, remove it from the header.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-30 15:38:33 -04:00
Jiri Olsa
ed61e8c59b kretprobe: Prevent triggering kretprobe from within kprobe_flush_task
[ Upstream commit 9b38cc704e844e41d9cf74e647bff1d249512cb3 ]

Ziqian reported lockup when adding retprobe on _raw_spin_lock_irqsave.
My test was also able to trigger lockdep output:

 ============================================
 WARNING: possible recursive locking detected
 5.6.0-rc6+ #6 Not tainted
 --------------------------------------------
 sched-messaging/2767 is trying to acquire lock:
 ffffffff9a492798 (&(kretprobe_table_locks[i].lock)){-.-.}, at: kretprobe_hash_lock+0x52/0xa0

 but task is already holding lock:
 ffffffff9a491a18 (&(kretprobe_table_locks[i].lock)){-.-.}, at: kretprobe_trampoline+0x0/0x50

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&(kretprobe_table_locks[i].lock));
   lock(&(kretprobe_table_locks[i].lock));

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 1 lock held by sched-messaging/2767:
  #0: ffffffff9a491a18 (&(kretprobe_table_locks[i].lock)){-.-.}, at: kretprobe_trampoline+0x0/0x50

 stack backtrace:
 CPU: 3 PID: 2767 Comm: sched-messaging Not tainted 5.6.0-rc6+ #6
 Call Trace:
  dump_stack+0x96/0xe0
  __lock_acquire.cold.57+0x173/0x2b7
  ? native_queued_spin_lock_slowpath+0x42b/0x9e0
  ? lockdep_hardirqs_on+0x590/0x590
  ? __lock_acquire+0xf63/0x4030
  lock_acquire+0x15a/0x3d0
  ? kretprobe_hash_lock+0x52/0xa0
  _raw_spin_lock_irqsave+0x36/0x70
  ? kretprobe_hash_lock+0x52/0xa0
  kretprobe_hash_lock+0x52/0xa0
  trampoline_handler+0xf8/0x940
  ? kprobe_fault_handler+0x380/0x380
  ? find_held_lock+0x3a/0x1c0
  kretprobe_trampoline+0x25/0x50
  ? lock_acquired+0x392/0xbc0
  ? _raw_spin_lock_irqsave+0x50/0x70
  ? __get_valid_kprobe+0x1f0/0x1f0
  ? _raw_spin_unlock_irqrestore+0x3b/0x40
  ? finish_task_switch+0x4b9/0x6d0
  ? __switch_to_asm+0x34/0x70
  ? __switch_to_asm+0x40/0x70

The code within the kretprobe handler checks for probe reentrancy,
so we won't trigger any _raw_spin_lock_irqsave probe in there.

The problem is in outside kprobe_flush_task, where we call:

  kprobe_flush_task
    kretprobe_table_lock
      raw_spin_lock_irqsave
        _raw_spin_lock_irqsave

where _raw_spin_lock_irqsave triggers the kretprobe and installs
kretprobe_trampoline handler on _raw_spin_lock_irqsave return.

The kretprobe_trampoline handler is then executed with already
locked kretprobe_table_locks, and first thing it does is to
lock kretprobe_table_locks ;-) the whole lockup path like:

  kprobe_flush_task
    kretprobe_table_lock
      raw_spin_lock_irqsave
        _raw_spin_lock_irqsave ---> probe triggered, kretprobe_trampoline installed

        ---> kretprobe_table_locks locked

        kretprobe_trampoline
          trampoline_handler
            kretprobe_hash_lock(current, &head, &flags);  <--- deadlock

Adding kprobe_busy_begin/end helpers that mark code with fake
probe installed to prevent triggering of another kprobe within
this code.

Using these helpers in kprobe_flush_task, so the probe recursion
protection check is hit and the probe is never set to prevent
above lockup.

Link: http://lkml.kernel.org/r/158927059835.27680.7011202830041561604.stgit@devnote2

Fixes: ef53d9c5e4da ("kprobes: improve kretprobe scalability with hashed locking")
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "Gustavo A . R . Silva" <gustavoars@kernel.org>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: "Naveen N . Rao" <naveen.n.rao@linux.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Reported-by: "Ziqian SUN (Zamir)" <zsun@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30 15:38:33 -04:00
Ahmed S. Darwish
5fbc7c9427 block: nr_sects_write(): Disable preemption on seqcount write
[ Upstream commit 15b81ce5abdc4b502aa31dff2d415b79d2349d2f ]

For optimized block readers not holding a mutex, the "number of sectors"
64-bit value is protected from tearing on 32-bit architectures by a
sequence counter.

Disable preemption before entering that sequence counter's write side
critical section. Otherwise, the read side can preempt the write side
section and spin for the entire scheduler tick. If the reader belongs to
a real-time scheduling class, it can spin forever and the kernel will
livelock.

Fixes: c83f6bf98dc1 ("block: add partition resize function to blkpg ioctl")
Cc: <stable@vger.kernel.org>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30 15:38:32 -04:00
Kai-Heng Feng
3a4b09605f libata: Use per port sync for detach
[ Upstream commit b5292111de9bb70cba3489075970889765302136 ]

Commit 130f4caf145c ("libata: Ensure ata_port probe has completed before
detach") may cause system freeze during suspend.

Using async_synchronize_full() in PM callbacks is wrong, since async
callbacks that are already scheduled may wait for not-yet-scheduled
callbacks, causes a circular dependency.

Instead of using big hammer like async_synchronize_full(), use async
cookie to make sure port probe are synced, without affecting other
scheduled PM callbacks.

Fixes: 130f4caf145c ("libata: Ensure ata_port probe has completed before detach")
Suggested-by: John Garry <john.garry@huawei.com>
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Tested-by: John Garry <john.garry@huawei.com>
BugLink: https://bugs.launchpad.net/bugs/1867983
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30 15:38:31 -04:00
Nick Desaulniers
1bb5b80d07 elfnote: mark all .note sections SHF_ALLOC
[ Upstream commit 51da9dfb7f20911ae4e79e9b412a9c2d4c373d4b ]

ELFNOTE_START allows callers to specify flags for .pushsection assembler
directives.  All callsites but ELF_NOTE use "a" for SHF_ALLOC.  For vdso's
that explicitly use ELF_NOTE_START and BUILD_SALT, the same section is
specified twice after preprocessing, once with "a" flag, once without.
Example:

.pushsection .note.Linux, "a", @note ;
.pushsection .note.Linux, "", @note ;

While GNU as allows this ordering, it warns for the opposite ordering,
making these directives position dependent.  We'd prefer not to precisely
match this behavior in Clang's integrated assembler.  Instead, the non
__ASSEMBLY__ definition of ELF_NOTE uses
__attribute__((section(".note.Linux"))) which is created with SHF_ALLOC,
so let's make the __ASSEMBLY__ definition of ELF_NOTE consistent with C
and just always use "a" flag.

This allows Clang to assemble a working mainline (5.6) kernel via:
$ make CC=clang AS=clang

Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Fangrui Song <maskray@google.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/913
Link: http://lkml.kernel.org/r/20200325231250.99205-1-ndesaulniers@google.com
Debugged-by: Ilie Halip <ilie.halip@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30 15:38:29 -04:00
Arnd Bergmann
ea20271753 include/linux/bitops.h: avoid clang shift-count-overflow warnings
[ Upstream commit bd93f003b7462ae39a43c531abca37fe7073b866 ]

Clang normally does not warn about certain issues in inline functions when
it only happens in an eliminated code path. However if something else
goes wrong, it does tend to complain about the definition of hweight_long()
on 32-bit targets:

  include/linux/bitops.h:75:41: error: shift count >= width of type [-Werror,-Wshift-count-overflow]
          return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
                                                 ^~~~~~~~~~~~
  include/asm-generic/bitops/const_hweight.h:29:49: note: expanded from macro 'hweight64'
   define hweight64(w) (__builtin_constant_p(w) ? __const_hweight64(w) : __arch_hweight64(w))
                                                  ^~~~~~~~~~~~~~~~~~~~
  include/asm-generic/bitops/const_hweight.h:21:76: note: expanded from macro '__const_hweight64'
   define __const_hweight64(w) (__const_hweight32(w) + __const_hweight32((w) >> 32))
                                                                             ^  ~~
  include/asm-generic/bitops/const_hweight.h:20:49: note: expanded from macro '__const_hweight32'
   define __const_hweight32(w) (__const_hweight16(w) + __const_hweight16((w) >> 16))
                                                  ^
  include/asm-generic/bitops/const_hweight.h:19:72: note: expanded from macro '__const_hweight16'
   define __const_hweight16(w) (__const_hweight8(w)  + __const_hweight8((w)  >> 8 ))
                                                                         ^
  include/asm-generic/bitops/const_hweight.h:12:9: note: expanded from macro '__const_hweight8'
            (!!((w) & (1ULL << 2))) +     \

Adding an explicit cast to __u64 avoids that warning and makes it easier
to read other output.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Link: http://lkml.kernel.org/r/20200505135513.65265-1-arnd@arndb.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30 15:38:29 -04:00
Pawel Laszczak
b4a4925ab8 usb: gadget: Fix issue with config_ep_by_speed function
[ Upstream commit 5d363120aa548ba52d58907a295eee25f8207ed2 ]

This patch adds new config_ep_by_speed_and_alt function which
extends the config_ep_by_speed about alt parameter.
This additional parameter allows to find proper usb_ss_ep_comp_descriptor.

Problem has appeared during testing f_tcm (BOT/UAS) driver function.

f_tcm function for SS use array of headers for both  BOT/UAS alternate
setting:

static struct usb_descriptor_header *uasp_ss_function_desc[] = {
        (struct usb_descriptor_header *) &bot_intf_desc,
        (struct usb_descriptor_header *) &uasp_ss_bi_desc,
        (struct usb_descriptor_header *) &bot_bi_ep_comp_desc,
        (struct usb_descriptor_header *) &uasp_ss_bo_desc,
        (struct usb_descriptor_header *) &bot_bo_ep_comp_desc,

        (struct usb_descriptor_header *) &uasp_intf_desc,
        (struct usb_descriptor_header *) &uasp_ss_bi_desc,
        (struct usb_descriptor_header *) &uasp_bi_ep_comp_desc,
        (struct usb_descriptor_header *) &uasp_bi_pipe_desc,
        (struct usb_descriptor_header *) &uasp_ss_bo_desc,
        (struct usb_descriptor_header *) &uasp_bo_ep_comp_desc,
        (struct usb_descriptor_header *) &uasp_bo_pipe_desc,
        (struct usb_descriptor_header *) &uasp_ss_status_desc,
        (struct usb_descriptor_header *) &uasp_status_in_ep_comp_desc,
        (struct usb_descriptor_header *) &uasp_status_pipe_desc,
        (struct usb_descriptor_header *) &uasp_ss_cmd_desc,
        (struct usb_descriptor_header *) &uasp_cmd_comp_desc,
        (struct usb_descriptor_header *) &uasp_cmd_pipe_desc,
        NULL,
};

The first 5 descriptors are associated with BOT alternate setting,
and others are associated with UAS.

During handling UAS alternate setting f_tcm driver invokes
config_ep_by_speed and this function sets incorrect companion endpoint
descriptor in usb_ep object.

Instead setting ep->comp_desc to uasp_bi_ep_comp_desc function in this
case set ep->comp_desc to uasp_ss_bi_desc.

This is due to the fact that it searches endpoint based on endpoint
address:

        for_each_ep_desc(speed_desc, d_spd) {
                chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
                if (chosen_desc->bEndpoitAddress == _ep->address)
                        goto ep_found;
        }

And in result it uses the descriptor from BOT alternate setting
instead UAS.

Finally, it causes that controller driver during enabling endpoints
detect that just enabled endpoint for bot.

Signed-off-by: Jayshri Pawar <jpawar@cadence.com>
Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30 15:38:27 -04:00
NeilBrown
d32887e72c sunrpc: clean up properly in gss_mech_unregister()
commit 24c5efe41c29ee3e55bcf5a1c9f61ca8709622e8 upstream.

gss_mech_register() calls svcauth_gss_register_pseudoflavor() for each
flavour, but gss_mech_unregister() does not call auth_domain_put().
This is unbalanced and makes it impossible to reload the module.

Change svcauth_gss_register_pseudoflavor() to return the registered
auth_domain, and save it for later release.

Cc: stable@vger.kernel.org (v2.6.12+)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206651
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-20 10:24:21 +02:00
Daniel Thompson
fb228bf21e kgdb: Fix spurious true from in_dbg_master()
[ Upstream commit 3fec4aecb311995189217e64d725cfe84a568de3 ]

Currently there is a small window where a badly timed migration could
cause in_dbg_master() to spuriously return true. Specifically if we
migrate to a new core after reading the processor id and the previous
core takes a breakpoint then we will evaluate true if we read
kgdb_active before we get the IPI to bring us to halt.

Fix this by checking irqs_disabled() first. Interrupts are always
disabled when we are executing the kgdb trap so this is an acceptable
prerequisite. This also allows us to replace raw_smp_processor_id()
with smp_processor_id() since the short circuit logic will prevent
warnings from PREEMPT_DEBUG.

Fixes: dcc7871128e9 ("kgdb: core changes to support kdb")
Suggested-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200506164223.2875760-1-daniel.thompson@linaro.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-20 10:24:16 +02:00
Jon Doron
64a3108d20 x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exit
[ Upstream commit f7d31e65368aeef973fab788aa22c4f1d5a6af66 ]

The problem the patch is trying to address is the fact that 'struct
kvm_hyperv_exit' has different layout on when compiling in 32 and 64 bit
modes.

In 64-bit mode the default alignment boundary is 64 bits thus
forcing extra gaps after 'type' and 'msr' but in 32-bit mode the
boundary is at 32 bits thus no extra gaps.

This is an issue as even when the kernel is 64 bit, the userspace using
the interface can be both 32 and 64 bit but the same 32 bit userspace has
to work with 32 bit kernel.

The issue is fixed by forcing the 64 bit layout, this leads to ABI
change for 32 bit builds and while we are obviously breaking '32 bit
userspace with 32 bit kernel' case, we're fixing the '32 bit userspace
with 64 bit kernel' one.

As the interface has no (known) users and 32 bit KVM is rather baroque
nowadays, this seems like a reasonable decision.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Jon Doron <arilou@gmail.com>
Message-Id: <20200424113746.3473563-2-arilou@gmail.com>
Reviewed-by: Roman Kagan <rvkagan@yandex-team.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-20 10:24:14 +02:00
Colin Ian King
77d5f7fe23 media: dvb_frontend: ensure that inital front end status initialized
commit a9e4998073d49a762a154a6b48a332ec6cb8e6b1 upstream.

The fe_status variable s is not initialized meaning it can have any
random garbage status.  This could be problematic if fe->ops.tune is
false as s is not updated by the call to fe->ops.tune() and a
subsequent check on the change status will using a garbage value.
Fix this by adding FE_NONE to the enum fe_status and initializing
s to this.

Detected by CoverityScan, CID#112887 ("Uninitialized scalar variable")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-20 10:24:13 +02:00
Mark Gross
5f8f40583a x86/cpu: Add a steppings field to struct x86_cpu_id
commit e9d7144597b10ff13ff2264c059f7d4a7fbc89ac upstream

Intel uses the same family/model for several CPUs. Sometimes the
stepping must be checked to tell them apart.

On x86 there can be at most 16 steppings. Add a steppings bitmask to
x86_cpu_id and a X86_MATCH_VENDOR_FAMILY_MODEL_STEPPING_FEATURE macro
and support for matching against family/model/stepping.

 [ bp: Massage.
   tglx: Lightweight variant for backporting ]

Signed-off-by: Mark Gross <mgross@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-11 09:22:23 +02:00
Jérôme Pouiller
a7481f5f1a mmc: fix compilation of user API
commit 83fc5dd57f86c3ec7d6d22565a6ff6c948853b64 upstream.

The definitions of MMC_IOC_CMD  and of MMC_IOC_MULTI_CMD rely on
MMC_BLOCK_MAJOR:

    #define MMC_IOC_CMD       _IOWR(MMC_BLOCK_MAJOR, 0, struct mmc_ioc_cmd)
    #define MMC_IOC_MULTI_CMD _IOWR(MMC_BLOCK_MAJOR, 1, struct mmc_ioc_multi_cmd)

However, MMC_BLOCK_MAJOR is defined in linux/major.h and
linux/mmc/ioctl.h did not include it.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200511161902.191405-1-Jerome.Pouiller@silabs.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-11 09:22:20 +02:00
Pablo Neira Ayuso
2395335b45 netfilter: nf_conntrack_pptp: fix compilation warning with W=1 build
commit 4946ea5c1237036155c3b3a24f049fd5f849f8f6 upstream.

>> include/linux/netfilter/nf_conntrack_pptp.h:13:20: warning: 'const' type qualifier on return type has no effect [-Wignored-qualifiers]
extern const char *const pptp_msg_name(u_int16_t msg);
^~~~~~

Reported-by: kbuild test robot <lkp@intel.com>
Fixes: 4c559f15efcc ("netfilter: nf_conntrack_pptp: prevent buffer overflows in debug code")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-03 08:16:46 +02:00
Pablo Neira Ayuso
8ef576491c netfilter: nf_conntrack_pptp: prevent buffer overflows in debug code
commit 4c559f15efcc43b996f4da528cd7f9483aaca36d upstream.

Dan Carpenter says: "Smatch complains that the value for "cmd" comes
from the network and can't be trusted."

Add pptp_msg_name() helper function that checks for the array boundary.

Fixes: f09943fefe6b ("[NETFILTER]: nf_conntrack/nf_nat: add PPTP helper port")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-03 08:16:46 +02:00
Arnd Bergmann
4f4a4bc907 include/asm-generic/topology.h: guard cpumask_of_node() macro argument
[ Upstream commit 4377748c7b5187c3342a60fa2ceb60c8a57a8488 ]

drivers/hwmon/amd_energy.c:195:15: error: invalid operands to binary expression ('void' and 'int')
                                        (channel - data->nr_cpus));
                                        ~~~~~~~~~^~~~~~~~~~~~~~~~~
include/asm-generic/topology.h:51:42: note: expanded from macro 'cpumask_of_node'
    #define cpumask_of_node(node)       ((void)node, cpu_online_mask)
                                               ^~~~
include/linux/cpumask.h:618:72: note: expanded from macro 'cpumask_first_and'
 #define cpumask_first_and(src1p, src2p) cpumask_next_and(-1, (src1p), (src2p))
                                                                       ^~~~~

Fixes: f0b848ce6fe9 ("cpumask: Introduce cpumask_of_{node,pcibus} to replace {node,pcibus}_to_cpumask")
Fixes: 8abee9566b7e ("hwmon: Add amd_energy driver to report energy counters")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: http://lkml.kernel.org/r/20200527134623.930247-1-arnd@arndb.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-03 08:16:42 +02:00
Konstantin Khlebnikov
584da13a92 mm: remove VM_BUG_ON(PageSlab()) from page_mapcount()
[ Upstream commit 6988f31d558aa8c744464a7f6d91d34ada48ad12 ]

Replace superfluous VM_BUG_ON() with comment about correct usage.

Technically reverts commit 1d148e218a0d ("mm: add VM_BUG_ON_PAGE() to
page_mapcount()"), but context lines have changed.

Function isolate_migratepages_block() runs some checks out of lru_lock
when choose pages for migration.  After checking PageLRU() it checks
extra page references by comparing page_count() and page_mapcount().
Between these two checks page could be removed from lru, freed and taken
by slab.

As a result this race triggers VM_BUG_ON(PageSlab()) in page_mapcount().
Race window is tiny.  For certain workload this happens around once a
year.

    page:ffffea0105ca9380 count:1 mapcount:0 mapping:ffff88ff7712c180 index:0x0 compound_mapcount: 0
    flags: 0x500000000008100(slab|head)
    raw: 0500000000008100 dead000000000100 dead000000000200 ffff88ff7712c180
    raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
    page dumped because: VM_BUG_ON_PAGE(PageSlab(page))
    ------------[ cut here ]------------
    kernel BUG at ./include/linux/mm.h:628!
    invalid opcode: 0000 [#1] SMP NOPTI
    CPU: 77 PID: 504 Comm: kcompactd1 Tainted: G        W         4.19.109-27 #1
    Hardware name: Yandex T175-N41-Y3N/MY81-EX0-Y3N, BIOS R05 06/20/2019
    RIP: 0010:isolate_migratepages_block+0x986/0x9b0

The code in isolate_migratepages_block() was added in commit
119d6d59dcc0 ("mm, compaction: avoid isolating pinned pages") before
adding VM_BUG_ON into page_mapcount().

This race has been predicted in 2015 by Vlastimil Babka (see link
below).

[akpm@linux-foundation.org: comment tweaks, per Hugh]
Fixes: 1d148e218a0d ("mm: add VM_BUG_ON_PAGE() to page_mapcount()")
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/159032779896.957378.7852761411265662220.stgit@buzz
Link: https://lore.kernel.org/lkml/557710E1.6060103@suse.cz/
Link: https://lore.kernel.org/linux-mm/158937872515.474360.5066096871639561424.stgit@buzz/T/ (v1)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-03 08:16:42 +02:00
Kalderon, Michal
d14e9ab0db IB/cma: Fix reference count leak when no ipv4 addresses are set
commit 963916fdb3e5ad4af57ac959b5a03bf23f7568ca upstream.

Once in_dev_get is called to receive in_device pointer, the
in_device reference counter is increased, but if there are
no ipv4 addresses configured on the net-device the ifa_list
will be null, resulting in a flow that doesn't call in_dev_put
to decrease the ref_cnt.
This was exposed when running RoCE over ipv6 without any ipv4
addresses configured

Fixes: commit 8e3867310c90 ("IB/cma: Fix a race condition in iboe_addr_get_sgid()")

Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-03 08:16:33 +02:00
b3a6fd241f uapi: fix linux/if_pppol2tp.h userspace compilation errors
commit a725eb15db80643a160310ed6bcfd6c5a6c907f2 upstream.

Because of <linux/libc-compat.h> interface limitations, <netinet/in.h>
provided by libc cannot be included after <linux/in.h>, therefore any
header that includes <netinet/in.h> cannot be included after <linux/in.h>.

Change uapi/linux/l2tp.h, the last uapi header that includes
<netinet/in.h>, to include <linux/in.h> and <linux/in6.h> instead of
<netinet/in.h> and use __SOCK_SIZE__ instead of sizeof(struct sockaddr)
the same way as uapi/linux/in.h does, to fix linux/if_pppol2tp.h userspace
compilation errors like this:

In file included from /usr/include/linux/l2tp.h:12:0,
                 from /usr/include/linux/if_pppol2tp.h:21,
/usr/include/netinet/in.h:31:8: error: redefinition of 'struct in_addr'

Fixes: 47c3e7783be4 ("net: l2tp: deprecate PPPOL2TP_MSG_* in favour of L2TP_MSG_*")
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Asbjoern Sloth Toennesen <asbjorn@asbjorn.st>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-03 08:16:33 +02:00
Moshe Shemesh
87959b0f5a net/mlx5: Add command entry handling completion
[ Upstream commit 17d00e839d3b592da9659c1977d45f85b77f986a ]

When FW response to commands is very slow and all command entries in
use are waiting for completion we can have a race where commands can get
timeout before they get out of the queue and handled. Timeout
completion on uninitialized command will cause releasing command's
buffers before accessing it for initialization and then we will get NULL
pointer exception while trying access it. It may also cause releasing
buffers of another command since we may have timeout completion before
even allocating entry index for this command.
Add entry handling completion to avoid this race.

Fixes: e126ba97dba9 ("mlx5: Add driver for Mellanox Connect-IB adapters")
Signed-off-by: Moshe Shemesh <moshe@mellanox.com>
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-03 08:16:31 +02:00
Roman Mashak
9a729a4798 net sched: fix reporting the first-time use timestamp
[ Upstream commit b15e62631c5f19fea9895f7632dae9c1b27fe0cd ]

When a new action is installed, firstuse field of 'tcf_t' is explicitly set
to 0. Value of zero means "new action, not yet used"; as a packet hits the
action, 'firstuse' is stamped with the current jiffies value.

tcf_tm_dump() should return 0 for firstuse if action has not yet been hit.

Fixes: 48d8ee1694dd ("net sched actions: aggregate dumping of actions timeinfo")
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Roman Mashak <mrv@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-03 08:16:25 +02:00
R. Parameswaran
e6cfc1098e l2tp: device MTU setup, tunnel socket needs a lock
commit 57240d007816486131bee88cd474c2a71f0fe224 upstream.

The MTU overhead calculation in L2TP device set-up
merged via commit b784e7ebfce8cfb16c6f95e14e8532d0768ab7ff
needs to be adjusted to lock the tunnel socket while
referencing the sub-data structures to derive the
socket's IP overhead.

Reported-by: Guillaume Nault <g.nault@alphalink.fr>
Tested-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: R. Parameswaran <rparames@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Giuliano Procida <gprocida@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 16:42:00 +02:00
R. Parameswaran
b25415f9f0 New kernel function to get IP overhead on a socket.
commit 113c3075931a334f899008f6c753abe70a3a9323 upstream.

A new function, kernel_sock_ip_overhead(), is provided
to calculate the cumulative overhead imposed by the IP
Header and IP options, if any, on a socket's payload.
The new function returns an overhead of zero for sockets
that do not belong to the IPv4 or IPv6 address families.
This is used in the L2TP code path to compute the
total outer IP overhead on the L2TP tunnel socket when
calculating the default MTU for Ethernet pseudowires.

Signed-off-by: R. Parameswaran <rparames@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Giuliano Procida <gprocida@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 16:41:54 +02:00
Asbjørn Sloth Tønnesen
cc84b4ddee net: l2tp: deprecate PPPOL2TP_MSG_* in favour of L2TP_MSG_*
commit 47c3e7783be4e142b861d34b5c2e223330b05d8a upstream.

PPPOL2TP_MSG_* and L2TP_MSG_* are duplicates, and are being used
interchangeably in the kernel, so let's standardize on L2TP_MSG_*
internally, and keep PPPOL2TP_MSG_* defined in UAPI for compatibility.

Signed-off-by: Asbjoern Sloth Toennesen <asbjorn@asbjorn.st>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Giuliano Procida <gprocida@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 16:41:53 +02:00
Asbjørn Sloth Tønnesen
18dc6fbbd9 net: l2tp: export debug flags to UAPI
commit 41c43fbee68f4f9a2a9675d83bca91c77862d7f0 upstream.

Move the L2TP_MSG_* definitions to UAPI, as it is part of
the netlink API.

Signed-off-by: Asbjoern Sloth Toennesen <asbjorn@asbjorn.st>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Giuliano Procida <gprocida@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 16:41:53 +02:00
Herbert Xu
f501513bd2 padata: Replace delayed timer with immediate workqueue in padata_reorder
[ Upstream commit 6fc4dbcf0276279d488c5fbbfabe94734134f4fa ]

The function padata_reorder will use a timer when it cannot progress
while completed jobs are outstanding (pd->reorder_objects > 0).  This
is suboptimal as if we do end up using the timer then it would have
introduced a gratuitous delay of one second.

In fact we can easily distinguish between whether completed jobs
are outstanding and whether we can make progress.  All we have to
do is look at the next pqueue list.

This patch does that by replacing pd->processed with pd->cpu so
that the next pqueue is more accessible.

A work queue is used instead of the original try_again to avoid
hogging the CPU.

Note that we don't bother removing the work queue in
padata_flush_queues because the whole premise is broken.  You
cannot flush async crypto requests so it makes no sense to even
try.  A subsequent patch will fix it by replacing it with a ref
counting scheme.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[dj: - adjust context
     - corrected setup_timer -> timer_setup to delete hunk
     - skip padata_flush_queues() hunk, function already removed
       in 4.9]
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27 16:41:52 +02:00
Mathias Krause
6953f88cd3 padata: ensure padata_do_serial() runs on the correct CPU
commit 350ef88e7e922354f82a931897ad4a4ce6c686ff upstream.

If the algorithm we're parallelizing is asynchronous we might change
CPUs between padata_do_parallel() and padata_do_serial(). However, we
don't expect this to happen as we need to enqueue the padata object into
the per-cpu reorder queue we took it from, i.e. the same-cpu's parallel
queue.

Ensure we're not switching CPUs for a given padata object by tracking
the CPU within the padata object. If the serial callback gets called on
the wrong CPU, defer invoking padata_reorder() via a kernel worker on
the CPU we're expected to run on.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 16:41:38 +02:00
Mathias Krause
08257da7e7 padata: ensure the reorder timer callback runs on the correct CPU
commit cf5868c8a22dc2854b96e9569064bb92365549ca upstream.

The reorder timer function runs on the CPU where the timer interrupt was
handled which is not necessarily one of the CPUs of the 'pcpu' CPU mask
set.

Ensure the padata_reorder() callback runs on the correct CPU, which is
one in the 'pcpu' CPU mask set and, preferrably, the next expected one.
Do so by comparing the current CPU with the expected target CPU. If they
match, call padata_reorder() right away. If they differ, schedule a work
item on the target CPU that does the padata_reorder() call for us.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 16:41:38 +02:00
Borislav Petkov
b263060dba x86: Fix early boot crash on gcc-10, third try
commit a9a3ed1eff3601b63aea4fb462d8b3b92c7c1e7e upstream.

... or the odyssey of trying to disable the stack protector for the
function which generates the stack canary value.

The whole story started with Sergei reporting a boot crash with a kernel
built with gcc-10:

  Kernel panic — not syncing: stack-protector: Kernel stack is corrupted in: start_secondary
  CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc5—00235—gfffb08b37df9 #139
  Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M—D3H, BIOS F12 11/14/2013
  Call Trace:
    dump_stack
    panic
    ? start_secondary
    __stack_chk_fail
    start_secondary
    secondary_startup_64
  -—-[ end Kernel panic — not syncing: stack—protector: Kernel stack is corrupted in: start_secondary

This happens because gcc-10 tail-call optimizes the last function call
in start_secondary() - cpu_startup_entry() - and thus emits a stack
canary check which fails because the canary value changes after the
boot_init_stack_canary() call.

To fix that, the initial attempt was to mark the one function which
generates the stack canary with:

  __attribute__((optimize("-fno-stack-protector"))) ... start_secondary(void *unused)

however, using the optimize attribute doesn't work cumulatively
as the attribute does not add to but rather replaces previously
supplied optimization options - roughly all -fxxx options.

The key one among them being -fno-omit-frame-pointer and thus leading to
not present frame pointer - frame pointer which the kernel needs.

The next attempt to prevent compilers from tail-call optimizing
the last function call cpu_startup_entry(), shy of carving out
start_secondary() into a separate compilation unit and building it with
-fno-stack-protector, was to add an empty asm("").

This current solution was short and sweet, and reportedly, is supported
by both compilers but we didn't get very far this time: future (LTO?)
optimization passes could potentially eliminate this, which leads us
to the third attempt: having an actual memory barrier there which the
compiler cannot ignore or move around etc.

That should hold for a long time, but hey we said that about the other
two solutions too so...

Reported-by: Sergei Trofimovich <slyfox@gentoo.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Kalle Valo <kvalo@codeaurora.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200314164451.346497-1-slyfox@gentoo.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20 08:15:41 +02:00
Takashi Iwai
c13f1463d8 ALSA: rawmidi: Fix racy buffer resize under concurrent accesses
commit c1f6e3c818dd734c30f6a7eeebf232ba2cf3181d upstream.

The rawmidi core allows user to resize the runtime buffer via ioctl,
and this may lead to UAF when performed during concurrent reads or
writes: the read/write functions unlock the runtime lock temporarily
during copying form/to user-space, and that's the race window.

This patch fixes the hole by introducing a reference counter for the
runtime buffer read/write access and returns -EBUSY error when the
resize is performed concurrently against read/write.

Note that the ref count field is a simple integer instead of
refcount_t here, since the all contexts accessing the buffer is
basically protected with a spinlock, hence we need no expensive atomic
ops.  Also, note that this busy check is needed only against read /
write functions, and not in receive/transmit callbacks; the race can
happen only at the spinlock hole mentioned in the above, while the
whole function is protected for receive / transmit callbacks.

Reported-by: butt3rflyh4ck <butterflyhuangxx@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/CAFcO6XMWpUVK_yzzCpp8_XP7+=oUpQvuBeCbMffEDkpe8jWrfg@mail.gmail.com
Link: https://lore.kernel.org/r/s5heerw3r5z.wl-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20 08:15:40 +02:00
Linus Torvalds
5ba9126d70 gcc-10 warnings: fix low-hanging fruit
commit 9d82973e032e246ff5663c9805fbb5407ae932e3 upstream.

Due to a bug-report that was compiler-dependent, I updated one of my
machines to gcc-10.  That shows a lot of new warnings.  Happily they
seem to be mostly the valid kind, but it's going to cause a round of
churn for getting rid of them..

This is the really low-hanging fruit of removing a couple of zero-sized
arrays in some core code.  We have had a round of these patches before,
and we'll have many more coming, and there is nothing special about
these except that they were particularly trivial, and triggered more
warnings than most.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20 08:15:37 +02:00
Jason Gunthorpe
19427360c4 pnp: Use list_for_each_entry() instead of open coding
commit 01b2bafe57b19d9119413f138765ef57990921ce upstream.

Aside from good practice, this avoids a warning from gcc 10:

./include/linux/kernel.h:997:3: warning: array subscript -31 is outside array bounds of ‘struct list_head[1]’ [-Warray-bounds]
  997 |  ((type *)(__mptr - offsetof(type, member))); })
      |  ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/list.h:493:2: note: in expansion of macro ‘container_of’
  493 |  container_of(ptr, type, member)
      |  ^~~~~~~~~~~~
./include/linux/pnp.h:275:30: note: in expansion of macro ‘list_entry’
  275 | #define global_to_pnp_dev(n) list_entry(n, struct pnp_dev, global_list)
      |                              ^~~~~~~~~~
./include/linux/pnp.h:281:11: note: in expansion of macro ‘global_to_pnp_dev’
  281 |  (dev) != global_to_pnp_dev(&pnp_global); \
      |           ^~~~~~~~~~~~~~~~~
arch/x86/kernel/rtc.c:189:2: note: in expansion of macro ‘pnp_for_each_dev’
  189 |  pnp_for_each_dev(dev) {

Because the common code doesn't cast the starting list_head to the
containing struct.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
[ rjw: Whitespace adjustments ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20 08:15:36 +02:00
Arnd Bergmann
4bdea735b1 netfilter: conntrack: avoid gcc-10 zero-length-bounds warning
[ Upstream commit 2c407aca64977ede9b9f35158e919773cae2082f ]

gcc-10 warns around a suspicious access to an empty struct member:

net/netfilter/nf_conntrack_core.c: In function '__nf_conntrack_alloc':
net/netfilter/nf_conntrack_core.c:1522:9: warning: array subscript 0 is outside the bounds of an interior zero-length array 'u8[0]' {aka 'unsigned char[0]'} [-Wzero-length-bounds]
 1522 |  memset(&ct->__nfct_init_offset[0], 0,
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from net/netfilter/nf_conntrack_core.c:37:
include/net/netfilter/nf_conntrack.h:90:5: note: while referencing '__nfct_init_offset'
   90 |  u8 __nfct_init_offset[0];
      |     ^~~~~~~~~~~~~~~~~~

The code is correct but a bit unusual. Rework it slightly in a way that
does not trigger the warning, using an empty struct instead of an empty
array. There are probably more elegant ways to do this, but this is the
smallest change.

Fixes: c41884ce0562 ("netfilter: conntrack: avoid zeroing timer")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:15:36 +02:00
Vladis Dronov
89e8fc989f ptp: fix the race between the release of ptp_clock and cdev
commit a33121e5487b424339636b25c35d3a180eaa5f5e upstream.

In a case when a ptp chardev (like /dev/ptp0) is open but an underlying
device is removed, closing this file leads to a race. This reproduces
easily in a kvm virtual machine:

ts# cat openptp0.c
int main() { ... fp = fopen("/dev/ptp0", "r"); ... sleep(10); }
ts# uname -r
5.5.0-rc3-46cf053e
ts# cat /proc/cmdline
... slub_debug=FZP
ts# modprobe ptp_kvm
ts# ./openptp0 &
[1] 670
opened /dev/ptp0, sleeping 10s...
ts# rmmod ptp_kvm
ts# ls /dev/ptp*
ls: cannot access '/dev/ptp*': No such file or directory
ts# ...woken up
[   48.010809] general protection fault: 0000 [#1] SMP
[   48.012502] CPU: 6 PID: 658 Comm: openptp0 Not tainted 5.5.0-rc3-46cf053e #25
[   48.014624] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), ...
[   48.016270] RIP: 0010:module_put.part.0+0x7/0x80
[   48.017939] RSP: 0018:ffffb3850073be00 EFLAGS: 00010202
[   48.018339] RAX: 000000006b6b6b6b RBX: 6b6b6b6b6b6b6b6b RCX: ffff89a476c00ad0
[   48.018936] RDX: fffff65a08d3ea08 RSI: 0000000000000247 RDI: 6b6b6b6b6b6b6b6b
[   48.019470] ...                                              ^^^ a slub poison
[   48.023854] Call Trace:
[   48.024050]  __fput+0x21f/0x240
[   48.024288]  task_work_run+0x79/0x90
[   48.024555]  do_exit+0x2af/0xab0
[   48.024799]  ? vfs_write+0x16a/0x190
[   48.025082]  do_group_exit+0x35/0x90
[   48.025387]  __x64_sys_exit_group+0xf/0x10
[   48.025737]  do_syscall_64+0x3d/0x130
[   48.026056]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   48.026479] RIP: 0033:0x7f53b12082f6
[   48.026792] ...
[   48.030945] Modules linked in: ptp i6300esb watchdog [last unloaded: ptp_kvm]
[   48.045001] Fixing recursive fault but reboot is needed!

This happens in:

static void __fput(struct file *file)
{   ...
    if (file->f_op->release)
        file->f_op->release(inode, file); <<< cdev is kfree'd here
    if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL &&
             !(mode & FMODE_PATH))) {
        cdev_put(inode->i_cdev); <<< cdev fields are accessed here

Namely:

__fput()
  posix_clock_release()
    kref_put(&clk->kref, delete_clock) <<< the last reference
      delete_clock()
        delete_ptp_clock()
          kfree(ptp) <<< cdev is embedded in ptp
  cdev_put
    module_put(p->owner) <<< *p is kfree'd, bang!

Here cdev is embedded in posix_clock which is embedded in ptp_clock.
The race happens because ptp_clock's lifetime is controlled by two
refcounts: kref and cdev.kobj in posix_clock. This is wrong.

Make ptp_clock's sysfs device a parent of cdev with cdev_device_add()
created especially for such cases. This way the parent device with its
ptp_clock is not released until all references to the cdev are released.
This adds a requirement that an initialized but not exposed struct
device should be provided to posix_clock_register() by a caller instead
of a simple dev_t.

This approach was adopted from the commit 72139dfa2464 ("watchdog: Fix
the race between the release of watchdog_core_data and cdev"). See
details of the implementation in the commit 233ed09d7fda ("chardev: add
helper function to register char devs with a struct device").

Link: https://lore.kernel.org/linux-fsdevel/20191125125342.6189-1-vdronov@redhat.com/T/#u
Analyzed-by: Stephen Johnston <sjohnsto@redhat.com>
Analyzed-by: Vern Lovejoy <vlovejoy@redhat.com>
Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:15:32 +02:00
Logan Gunthorpe
da97a80a65 chardev: add helper function to register char devs with a struct device
commit 233ed09d7fdacf592ee91e6c97ce5f4364fbe7c0 upstream.

Credit for this patch goes is shared with Dan Williams [1]. I've
taken things one step further to make the helper function more
useful and clean up calling code.

There's a common pattern in the kernel whereby a struct cdev is placed
in a structure along side a struct device which manages the life-cycle
of both. In the naive approach, the reference counting is broken and
the struct device can free everything before the chardev code
is entirely released.

Many developers have solved this problem by linking the internal kobjs
in this fashion:

cdev.kobj.parent = &parent_dev.kobj;

The cdev code explicitly gets and puts a reference to it's kobj parent.
So this seems like it was intended to be used this way. Dmitrty Torokhov
first put this in place in 2012 with this commit:

2f0157f char_dev: pin parent kobject

and the first instance of the fix was then done in the input subsystem
in the following commit:

4a215aa Input: fix use-after-free introduced with dynamic minor changes

Subsequently over the years, however, this issue seems to have tripped
up multiple developers independently. For example, see these commits:

0d5b7da iio: Prevent race between IIO chardev opening and IIO device
(by Lars-Peter Clausen in 2013)

ba0ef85 tpm: Fix initialization of the cdev
(by Jason Gunthorpe in 2015)

5b28dde [media] media: fix use-after-free in cdev_put() when app exits
after driver unbind
(by Shauh Khan in 2016)

This technique is similarly done in at least 15 places within the kernel
and probably should have been done so in another, at least, 5 places.
The kobj line also looks very suspect in that one would not expect
drivers to have to mess with kobject internals in this way.
Even highly experienced kernel developers can be surprised by this
code, as seen in [2].

To help alleviate this situation, and hopefully prevent future
wasted effort on this problem, this patch introduces a helper function
to register a char device along with its parent struct device.
This creates a more regular API for tying a char device to its parent
without the developer having to set members in the underlying kobject.

This patch introduce cdev_device_add and cdev_device_del which
replaces a common pattern including setting the kobj parent, calling
cdev_add and then calling device_add. It also introduces cdev_set_parent
for the few cases that set the kobject parent without using device_add.

[1] https://lkml.org/lkml/2017/2/13/700
[2] https://lkml.org/lkml/2017/2/10/370

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:15:32 +02:00
Jan Kara
284dba674c blktrace: Protect q->blk_trace with RCU
commit c780e86dd48ef6467a1146cf7d0fe1e05a635039 upstream.

KASAN is reporting that __blk_add_trace() has a use-after-free issue
when accessing q->blk_trace. Indeed the switching of block tracing (and
thus eventual freeing of q->blk_trace) is completely unsynchronized with
the currently running tracing and thus it can happen that the blk_trace
structure is being freed just while __blk_add_trace() works on it.
Protect accesses to q->blk_trace by RCU during tracing and make sure we
wait for the end of RCU grace period when shutting down tracing. Luckily
that is rare enough event that we can afford that. Note that postponing
the freeing of blk_trace to an RCU callback should better be avoided as
it could have unexpected user visible side-effects as debugfs files
would be still existing for a short while block tracing has been shut
down.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=205711
CC: stable@vger.kernel.org
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reported-by: Tristan Madani <tristmd@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:15:31 +02:00
Waiman Long
b488092565 blktrace: Fix potential deadlock between delete & sysfs ops
commit 5acb3cc2c2e9d3020a4fee43763c6463767f1572 upstream.

The lockdep code had reported the following unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(s_active#228);
                               lock(&bdev->bd_mutex/1);
                               lock(s_active#228);
  lock(&bdev->bd_mutex);

 *** DEADLOCK ***

The deadlock may happen when one task (CPU1) is trying to delete a
partition in a block device and another task (CPU0) is accessing
tracing sysfs file (e.g. /sys/block/dm-1/trace/act_mask) in that
partition.

The s_active isn't an actual lock. It is a reference count (kn->count)
on the sysfs (kernfs) file. Removal of a sysfs file, however, require
a wait until all the references are gone. The reference count is
treated like a rwsem using lockdep instrumentation code.

The fact that a thread is in the sysfs callback method or in the
ioctl call means there is a reference to the opended sysfs or device
file. That should prevent the underlying block structure from being
removed.

Instead of using bd_mutex in the block_device structure, a new
blk_trace_mutex is now added to the request_queue structure to protect
access to the blk_trace structure.

Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Fix typo in patch subject line, and prune a comment detailing how
the code used to work.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:15:30 +02:00
Sabrina Dubroca
badbe56cb6 net: ipv6_stub: use ip6_dst_lookup_flow instead of ip6_dst_lookup
commit 6c8991f41546c3c472503dff1ea9daaddf9331c2 upstream.

ipv6_stub uses the ip6_dst_lookup function to allow other modules to
perform IPv6 lookups. However, this function skips the XFRM layer
entirely.

All users of ipv6_stub->ip6_dst_lookup use ip_route_output_flow (via the
ip_route_output_key and ip_route_output helpers) for their IPv4 lookups,
which calls xfrm_lookup_route(). This patch fixes this inconsistent
behavior by switching the stub to ip6_dst_lookup_flow, which also calls
xfrm_lookup_route().

This requires some changes in all the callers, as these two functions
take different arguments and have different return types.

Fixes: 5f81bd2e5d80 ("ipv6: export a stub for IPv6 symbols used by vxlan")
Reported-by: Xiumei Mu <xmu@redhat.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 4.9:
 - Drop changes in lwt_bpf.c and mlx5
 - Initialise "dst" in drivers/infiniband/core/addr.c:addr_resolve()
   to avoid introducing a spurious "may be used uninitialised" warning
 - Adjust filename, context, indentation]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:15:30 +02:00
Sabrina Dubroca
5cc5fa7a87 net: ipv6: add net argument to ip6_dst_lookup_flow
commit c4e85f73afb6384123e5ef1bba3315b2e3ad031e upstream.

This will be used in the conversion of ipv6_stub to ip6_dst_lookup_flow,
as some modules currently pass a net argument without a socket to
ip6_dst_lookup. This is equivalent to commit 343d60aada5a ("ipv6: change
ipv6_stub_impl.ipv6_dst_lookup to take net argument").

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 4.9: adjust context]
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:15:30 +02:00
Thomas Pedersen
9bb734d994 mac80211: add ieee80211_is_any_nullfunc()
commit 30b2f0be23fb40e58d0ad2caf8702c2a44cda2e1 upstream.

commit 08a5bdde3812 ("mac80211: consider QoS Null frames for STA_NULLFUNC_ACKED")
Fixed a bug where we failed to take into account a
nullfunc frame can be either non-QoS or QoS. It turns out
there is at least one more bug in
ieee80211_sta_tx_notify(), introduced in
commit 7b6ddeaf27ec ("mac80211: use QoS NDP for AP probing"),
where we forgot to check for the QoS variant and so
assumed the QoS nullfunc frame never went out

Fix this by adding a helper ieee80211_is_any_nullfunc()
which consolidates the check for non-QoS and QoS nullfunc
frames. Replace existing compound conditionals and add a
couple more missing checks for QoS variant.

Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20200114055940.18502-3-thomas@adapt-ip.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-10 10:28:03 +02:00
Sean Christopherson
a57c01c563 KVM: Check validity of resolved slot when searching memslots
commit b6467ab142b708dd076f6186ca274f14af379c72 upstream.

Check that the resolved slot (somewhat confusingly named 'start') is a
valid/allocated slot before doing the final comparison to see if the
specified gfn resides in the associated slot.  The resolved slot can be
invalid if the binary search loop terminated because the search index
was incremented beyond the number of used slots.

This bug has existed since the binary search algorithm was introduced,
but went unnoticed because KVM statically allocated memory for the max
number of slots, i.e. the access would only be truly out-of-bounds if
all possible slots were allocated and the specified gfn was less than
the base of the lowest memslot.  Commit 36947254e5f98 ("KVM: Dynamically
size memslot array based on number of used slots") eliminated the "all
possible slots allocated" condition and made the bug embarrasingly easy
to hit.

Fixes: 9c1a5d38780e6 ("kvm: optimize GFN to memslot lookup with large slots amount")
Reported-by: syzbot+d889b59b2bb87d4047a2@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Message-Id: <20200408064059.8957-2-sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02 17:23:11 +02:00