linux-stable.git/include, branch v5.7.7

drm/fb-helper: Fix vt restore

2020-06-30T19:36:28+00:00

commit dc5bdb68b5b369d5bc7d1de96fa64cc1737a6320 upstream.

In the past we had a pile of hacks to orchestrate access between fbdev
emulation and native kms clients. We've tried to streamline this, by
always preferring the kms side above fbdev calls when a drm master
exists, because drm master controls access to the display resources.

Unfortunately this breaks existing userspace, specifically Xorg. When
exiting Xorg first restores the console to text mode using the KDSET
ioctl on the vt. This does nothing, because a drm master is still
around. Then it drops the drm master status, which again does nothing,
because logind is keeping additional drm fd open to be able to
orchestrate vt switches. In the past this is the point where fbdev was
restored, as part of the ->lastclose hook on the drm side.

Now to fix this regression we don't want to go back to letting fbdev
restore things whenever it feels like, or to the pile of hacks we've
had before. Instead try and go with a minimal exception to make the
KDSET case work again, and nothing else.

This means that if userspace does a KDSET call when switching between
graphical compositors, there will be some flickering with fbcon
showing up for a bit. But a) that's not a regression and b) userspace
can fix it by improving the vt switching dance - logind should have
all the information it needs.

While pondering all this I'm also wondering wheter we should have a
SWITCH_MASTER ioctl to allow race-free master status handover. But
that's for another day.

v2: Somehow forgot to cc all the fbdev people.

v3: Fix typo Alex spotted.

Reviewed-by: Alex Deucher 
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=208179
Cc: shlomo@fastmail.com
Reported-and-Tested-by: shlomo@fastmail.com
Cc: Michel Dänzer 
Fixes: 64914da24ea9 ("drm/fbdev-helper: don't force restores")
Cc: Noralf Trønnes 
Cc: Thomas Zimmermann 
Cc: Daniel Vetter 
Cc: Maarten Lankhorst 
Cc: Maxime Ripard 
Cc: David Airlie 
Cc: Daniel Vetter 
Cc: dri-devel@lists.freedesktop.org
Cc:  # v5.7+
Cc: Bartlomiej Zolnierkiewicz 
Cc: Geert Uytterhoeven 
Cc: Nathan Chancellor 
Cc: Qiujun Huang 
Cc: Peter Rosin 
Cc: linux-fbdev@vger.kernel.org
Signed-off-by: Daniel Vetter 
Link: https://patchwork.freedesktop.org/patch/msgid/20200624092910.3280448-1-daniel.vetter@ffwll.ch
Signed-off-by: Greg Kroah-Hartman

syscalls: Fix offset type of ksys_ftruncate()

2020-06-30T19:36:19+00:00

commit 8e742aa79780b13cd300a42198c1a4cea9c89905 upstream.

After the commit below, truncate() on x86 32bit uses ksys_ftruncate(). But
ksys_ftruncate() truncates the offset to unsigned long.

Switch the type of offset to loff_t which is what do_sys_ftruncate()
expects.

Fixes: 121b32a58a3a (x86/entry/32: Use IA32-specific wrappers for syscalls taking 64-bit arguments)
Signed-off-by: Jiri Slaby 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Brian Gerst 
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200610114851.28549-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman

net: qed: fix left elements count calculation

2020-06-30T19:36:07+00:00

[ 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 
Signed-off-by: Igor Russkikh 
Signed-off-by: Michal Kalderon 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

iommu/vt-d: Set U/S bit in first level page table by default

2020-06-30T19:36:07+00:00

[ Upstream commit 16ecf10e815d70d11d2300243f4a3b4c7c5acac7 ]

When using first-level translation for IOVA, currently the U/S bit in the
page table is cleared which implies DMA requests with user privilege are
blocked. As the result, following error messages might be observed when
passing through a device to user level:

DMAR: DRHD: handling fault status reg 3
DMAR: [DMA Read] Request device [41:00.0] PASID 1 fault addr 7ecdcd000
        [fault reason 129] SM: U/S set 0 for first-level translation
        with user privilege

This fixes it by setting U/S bit in the first level page table and makes
IOVA over first level compatible with previous second-level translation.

Fixes: b802d070a52a1 ("iommu/vt-d: Use iova over first level")
Reported-by: Xin Zeng 
Signed-off-by: Lu Baolu 
Link: https://lore.kernel.org/r/20200622231345.29722-3-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel 
Signed-off-by: Sasha Levin

efi/tpm: Verify event log header before parsing

2020-06-30T19:36:01+00:00

[ Upstream commit 7dfc06a0f25b593a9f51992f540c0f80a57f3629 ]

It is possible that the first event in the event log is not actually a
log header at all, but rather a normal event. This leads to the cast in
__calc_tpm2_event_size being an invalid conversion, which means that
the values read are effectively garbage. Depending on the first event's
contents, this leads either to apparently normal behaviour, a crash or
a freeze.

While this behaviour of the firmware is not in accordance with the
TCG Client EFI Specification, this happens on a Dell Precision 5510
with the TPM enabled but hidden from the OS ("TPM On" disabled, state
otherwise untouched). The EFI firmware claims that the TPM is present
and active and that it supports the TCG 2.0 event log format.

Fortunately, this can be worked around by simply checking the header
of the first event and the event log header signature itself.

Commit b4f1874c6216 ("tpm: check event log version before reading final
events") addressed a similar issue also found on Dell models.

Fixes: 6b0326190205 ("efi: Attempt to get the TCG2 event log in the boot stub")
Signed-off-by: Fabian Vogt 
Link: https://lore.kernel.org/r/1927248.evlx2EsYKh@linux-e202.suse.de
Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=1165773
Signed-off-by: Ard Biesheuvel 
Signed-off-by: Sasha Levin

xfrm: Fix double ESP trailer insertion in IPsec crypto offload.

2020-06-30T19:36:00+00:00

[ Upstream commit 94579ac3f6d0820adc83b5dc5358ead0158101e9 ]

During IPsec performance testing, we see bad ICMP checksum. The error packet
has duplicated ESP trailer due to double validate_xmit_xfrm calls. The first call
is from ip_output, but the packet cannot be sent because
netif_xmit_frozen_or_stopped is true and the packet gets dev_requeue_skb. The second
call is from NET_TX softirq. However after the first call, the packet already
has the ESP trailer.

Fix by marking the skb with XFRM_XMIT bit after the packet is handled by
validate_xmit_xfrm to avoid duplicate ESP trailer insertion.

Fixes: f6e27114a60a ("net: Add a xfrm validate function to validate_xmit_skb")
Signed-off-by: Huy Nguyen 
Reviewed-by: Boris Pismenny 
Reviewed-by: Raed Salem 
Reviewed-by: Saeed Mahameed 
Signed-off-by: Steffen Klassert 
Signed-off-by: Sasha Levin

sctp: Don't advertise IPv4 addresses if ipv6only is set on the socket

2020-06-30T19:35:48+00:00

[ 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 
Signed-off-by: Marcelo Ricardo Leitner 
Tested-by: Corey Minyard 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: Do not clear the sock TX queue in sk_set_socket()

2020-06-30T19:35:46+00:00

[ 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 
Reviewed-by: Boris Pismenny 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: core: reduce recursion limit value

2020-06-30T19:35:46+00:00

[ 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 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

kretprobe: Prevent triggering kretprobe from within kprobe_flush_task

2020-06-24T15:49:25+00:00

commit 9b38cc704e844e41d9cf74e647bff1d249512cb3 upstream.

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 
Cc: "Gustavo A . R . Silva" 
Cc: Anders Roxell 
Cc: "Naveen N . Rao" 
Cc: Anil S Keshavamurthy 
Cc: David Miller 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: stable@vger.kernel.org
Reported-by: "Ziqian SUN (Zamir)" 
Acked-by: Masami Hiramatsu 
Signed-off-by: Jiri Olsa 
Signed-off-by: Steven Rostedt (VMware) 
Signed-off-by: Greg Kroah-Hartman