There should be no undefined symbols in the resulting VDSO image(s).

On sparc, fixed register usage can result in undefined symbols ending
up in the image.  To combat this, we do two things:

1) Define current_thread_info() specially when BUILD_DSO.

2) Ignore "#scratch" register undefined symbols in the output.

Signed-off-by: David S. Miller <davem@davemloft.net>

Rather than funneling through CC.

Also, use --hash-style=both just like other VDSO architectures and
glibc do.

Signed-off-by: David S. Miller <davem@davemloft.net>

Do not set any special register usage options, use the default which
is exactly what we should use for userspace code.

Make sure we remove the gcc plugin options from the 64-bit build.
The 32-bit cflags got it right already.

Signed-off-by: David S. Miller <davem@davemloft.net>

Not in vclock_gettime.c itself.

Signed-off-by: David S. Miller <davem@davemloft.net>

If the TICK_PRIV_BIT was set, we would not be able to read the tick
register in user space, which is where this code runs.

Signed-off-by: David S. Miller <davem@davemloft.net>

One interesting thing we need to do is stop using
__builtin_return_address() in get_vvar_data().

Simply read the %pc register instead.

Signed-off-by: David S. Miller <davem@davemloft.net>

The current VDSO patch mechanism has several problems:

1) It assumes how gcc will emit a function, with a register
   window, an initial save instruction and then immediately
   the %tick read when compiling vread_tick().

   There is no such guarantees, code generation could change
   at any time, gcc could put a nop between the save and
   the %tick read, etc.

   So this is extremely fragile and would fail some day.

2) It disallows us to properly inline vread_tick() into the callers
   and thus get the best possible code sequences.

So fix this to patch properly, with location based annotations.

We have to be careful because we cannot do it the way we do
patches elsewhere in the kernel.  Those use a sequence like:

	1:
	insn
	.section	.whatever_patch, "ax"
	.word		1b
	replacement_insn
	.previous

This is a dynamic shared object, so that .word cannot be resolved at
build time, and thus cannot be used to execute the patches when the
kernel initializes the images.

Even trying to use label difference equations doesn't work in the
above kind of scheme:

	1:
	insn
	.section	.whatever_patch, "ax"
	.word		. - 1b
	replacement_insn
	.previous

The assembler complains that it cannot resolve that computation.
The issue is that this is contained in an executable section.

Borrow the sequence used by x86 alternatives, which is:

	1:
	insn
	.pushsection	.whatever_patch, "a"
	.word		. - 1b, . - 1f
	.popsection
	.pushsection	.whatever_patch_replacements, "ax"
	1:
	replacement_insn
	.previous

This works, allows us to inline vread_tick() as much as we like, and
can be used for arbitrary kinds of VDSO patching in the future.

Also, reverse the condition for patching.  Most systems are %stick
based, so if we only patch on %tick systems the patching code will
get little or no testing.

Signed-off-by: David S. Miller <davem@davemloft.net>

If PARPORT_PC_FIFO is not enabled, do not provide the dma lock
macros and lock definition.  Otherwise:

./arch/sparc/include/asm/parport.h:24:24: warning: ‘dma_spin_lock’ defined but not used [-Wunused-variable]
 static DEFINE_SPINLOCK(dma_spin_lock);
                        ^~~~~~~~~~~~~
./include/linux/spinlock_types.h:81:39: note: in definition of macro ‘DEFINE_SPINLOCK’
 #define DEFINE_SPINLOCK(x) spinlock_t x = __SPIN_LOCK_UNLOCKED(x)

Signed-off-by: David S. Miller <davem@davemloft.net>

David writes:
  "Networking

   1) Fix gro_cells leak in xfrm layer, from Li RongQing.

   2) BPF selftests change RLIMIT_MEMLOCK blindly, don't do that.  From
      Eric Dumazet.

   3) AF_XDP calls synchronize_net() under RCU lock, fix from Björn
      Töpel.

   4) Out of bounds packet access in _decode_session6(), from Alexei
      Starovoitov.

   5) Several ethtool bugs, where we copy a struct into the kernel twice
      and our validations of the values in the first copy can be
      invalidated by the second copy due to asynchronous updates to the
      memory by the user.  From Wenwen Wang.

   6) Missing netlink attribute validation in cls_api, from Davide
      Caratti.

   7) LLC SAP sockets neet to be SOCK_RCU FREE, from Cong Wang.

   8) rxrpc operates on wrong kvec, from Yue Haibing.

   9) A regression was introduced by the disassosciation of route
      neighbour references in rt6_probe(), causing probe for
      neighbourless routes to not be properly rate limited.  Fix from
      Sabrina Dubroca.

   10) Unsafe RCU locking in tipc, from Tung Nguyen.

   11) Use after free in inet6_mc_check(), from Eric Dumazet.

   12) PMTU from icmp packets should update the SCTP transport pathmtu,
       from Xin Long.

   13) Missing peer put on error in rxrpc, from David Howells.

   14) Fix pedit in nfp driver, from Pieter Jansen van Vuuren.

   15) Fix overflowing shift statement in qla3xxx driver, from Nathan
       Chancellor.

   16) Fix Spectre v1 in ptp code, from Gustavo A. R. Silva.

   17) udp6_unicast_rcv_skb() interprets udpv6_queue_rcv_skb() return
       value in an inverted manner, fix from Paolo Abeni.

   18) Fix missed unresolved entries in ipmr dumps, from Nikolay
       Aleksandrov.

   19) Fix NAPI handling under high load, we can completely miss events
       when NAPI has to loop more than one time in a cycle.  From Heiner
       Kallweit."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (49 commits)
  ip6_tunnel: Fix encapsulation layout
  tipc: fix info leak from kernel tipc_event
  net: socket: fix a missing-check bug
  net: sched: Fix for duplicate class dump
  r8169: fix NAPI handling under high load
  net: ipmr: fix unresolved entry dumps
  net: mscc: ocelot: Fix comment in ocelot_vlant_wait_for_completion()
  sctp: fix the data size calculation in sctp_data_size
  virtio_net: avoid using netif_tx_disable() for serializing tx routine
  udp6: fix encap return code for resubmitting
  mlxsw: core: Fix use-after-free when flashing firmware during init
  sctp: not free the new asoc when sctp_wait_for_connect returns err
  sctp: fix race on sctp_id2asoc
  r8169: re-enable MSI-X on RTL8168g
  net: bpfilter: use get_pid_task instead of pid_task
  ptp: fix Spectre v1 vulnerability
  net: qla3xxx: Remove overflowing shift statement
  geneve, vxlan: Don't set exceptions if skb->len < mtu
  geneve, vxlan: Don't check skb_dst() twice
  sctp: get pr_assoc and pr_stream all status with SCTP_PR_SCTP_ALL instead
  ...

David writes:
  "Sparc fixes:

   The main bit here is fixing how fallback system calls are handled in
   the sparc vDSO.

   Unfortunately, I fat fingered the commit and some perf debugging
   hacks slipped into the vDSO fix, which I revert in the very next
   commit."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: Revert unintended perf changes.
  sparc: vDSO: Silence an uninitialized variable warning
  sparc: Fix syscall fallback bugs in VDSO.

Dave writes:
  "drm fixes for 4.19 final

   Just a last set of misc core fixes for final.

   4 fixes, one use after free, one fb integration fix, one EDID fix,
   and one laptop panel quirk,"

* tag 'drm-fixes-2018-10-19' of git://anongit.freedesktop.org/drm/drm:
  drm/edid: VSDB yCBCr420 Deep Color mode bit definitions
  drm: fix use of freed memory in drm_mode_setcrtc
  drm: fb-helper: Reject all pixel format changing requests
  drm/edid: Add 6 bpc quirk for BOE panel in HP Pavilion 15-n233sl

Doug writes:
  "Really final for-rc pull request for 4.19

   Ok, so last week I thought we had sent our final pull request for
   4.19.  Well, wouldn't ya know someone went and found a couple Spectre
   v1 fixes were needed :-/.  So, a couple *very* small specter patches
   for this (hopefully) final -rc week."

* tag 'for-gkh' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  RDMA/ucma: Fix Spectre v1 vulnerability
  IB/ucm: Fix Spectre v1 vulnerability

drm-misc-fixes for v4.19:
- Fix use of freed memory in drm_mode_setcrtc.
- Reject pixel format changing requests in fb helper.
- Add 6 bpc quirk for HP Pavilion 15-n233sl
- Fix VSDB yCBCr420 Deep Color mode bit definitions

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/647fe5d0-4ec5-57cc-9f23-a4836b29e278@linux.intel.com

Commit 058214a4 ("ip6_tun: Add infrastructure for doing
encapsulation") added the ip6_tnl_encap() call in ip6_tnl_xmit(), before
the call to ipv6_push_frag_opts() to append the IPv6 Tunnel Encapsulation
Limit option (option 4, RFC 2473, par. 5.1) to the outer IPv6 header.

As long as the option didn't actually end up in generated packets, this
wasn't an issue. Then commit 89a23c8b ("ip6_tunnel: Fix missing tunnel
encapsulation limit option") fixed sending of this option, and the
resulting layout, e.g. for FoU, is:

.-------------------.------------.----------.-------------------.----- - -
| Outer IPv6 Header | UDP header | Option 4 | Inner IPv6 Header | Payload
'-------------------'------------'----------'-------------------'----- - -

Needless to say, FoU and GUE (at least) won't work over IPv6. The option
is appended by default, and I couldn't find a way to disable it with the
current iproute2.

Turn this into a more reasonable:

.-------------------.----------.------------.-------------------.----- - -
| Outer IPv6 Header | Option 4 | UDP header | Inner IPv6 Header | Payload
'-------------------'----------'------------'-------------------'----- - -

With this, and with 84dad559 ("udp6: fix encap return code for
resubmitting"), FoU and GUE work again over IPv6.

Fixes: 058214a4

 ("ip6_tun: Add infrastructure for doing encapsulation")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We initialize a struct tipc_event allocated on the kernel stack to
zero to avert info leak to user space.

Reported-by:  <syzbot+057458894bc8cada4dee@syzkaller.appspotmail.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In ethtool_ioctl(), the ioctl command 'ethcmd' is checked through a switch
statement to see whether it is necessary to pre-process the ethtool
structure, because, as mentioned in the comment, the structure
ethtool_rxnfc is defined with padding. If yes, a user-space buffer 'rxnfc'
is allocated through compat_alloc_user_space(). One thing to note here is
that, if 'ethcmd' is ETHTOOL_GRXCLSRLALL, the size of the buffer 'rxnfc' is
partially determined by 'rule_cnt', which is actually acquired from the
user-space buffer 'compat_rxnfc', i.e., 'compat_rxnfc->rule_cnt', through
get_user(). After 'rxnfc' is allocated, the data in the original user-space
buffer 'compat_rxnfc' is then copied to 'rxnfc' through copy_in_user(),
including the 'rule_cnt' field. However, after this copy, no check is
re-enforced on 'rxnfc->rule_cnt'. So it is possible that a malicious user
race to change the value in the 'compat_rxnfc->rule_cnt' between these two
copies. Through this way, the attacker can bypass the previous check on
'rule_cnt' and inject malicious data. This can cause undefined behavior of
the kernel and introduce potential security risk.

This patch avoids the above issue via copying the value acquired by
get_user() to 'rxnfc->rule_cn', if 'ethcmd' is ETHTOOL_GRXCLSRLALL.

Signed-off-by: Wenwen Wang <wang6495@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>

When dumping classes by parent, kernel would return classes twice:

| # tc qdisc add dev lo root prio
| # tc class show dev lo
| class prio 8001:1 parent 8001:
| class prio 8001:2 parent 8001:
| class prio 8001:3 parent 8001:
| # tc class show dev lo parent 8001:
| class prio 8001:1 parent 8001:
| class prio 8001:2 parent 8001:
| class prio 8001:3 parent 8001:
| class prio 8001:1 parent 8001:
| class prio 8001:2 parent 8001:
| class prio 8001:3 parent 8001:

This comes from qdisc_match_from_root() potentially returning the root
qdisc itself if its handle matched. Though in that case, root's classes
were already dumped a few lines above.

Fixes: cb395b20

 ("net: sched: optimize class dumps")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtl_rx() and rtl_tx() are called only if the respective bits are set
in the interrupt status register. Under high load NAPI may not be
able to process all data (work_done == budget) and it will schedule
subsequent calls to the poll callback.
rtl_ack_events() however resets the bits in the interrupt status
register, therefore subsequent calls to rtl8169_poll() won't call
rtl_rx() and rtl_tx() - chip interrupts are still disabled.

Fix this by calling rtl_rx() and rtl_tx() independent of the bits
set in the interrupt status register. Both functions will detect
if there's nothing to do for them.

Fixes: da78dbff

 ("r8169: remove work from irq handler.")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Some local debugging hacks accidently slipped into the VDSO commit.

Sorry!

Signed-off-by: David S. Miller <davem@davemloft.net>

Steffen Klassert says:

====================
pull request (net): ipsec 2018-10-18

1) Free the xfrm interface gro_cells when deleting the
   interface, otherwise we leak it. From Li RongQing.

2) net/core/flow.c does not exist anymore, so remove it
   from the MAINTAINERS file.

3) Fix a slab-out-of-bounds in _decode_session6.
   From Alexei Starovoitov.

4) Fix RCU protection when policies inserted into
   thei bydst lists. From Florian Westphal.

Please pull or let me know if there are problems.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

fscache_set_key() can incur an out-of-bounds read, reported by KASAN:

 BUG: KASAN: slab-out-of-bounds in fscache_alloc_cookie+0x5b3/0x680 [fscache]
 Read of size 4 at addr ffff88084ff056d4 by task mount.nfs/32615

and also reported by syzbot at https://lkml.org/lkml/2018/7/8/236

  BUG: KASAN: slab-out-of-bounds in fscache_set_key fs/fscache/cookie.c:120 [inline]
  BUG: KASAN: slab-out-of-bounds in fscache_alloc_cookie+0x7a9/0x880 fs/fscache/cookie.c:171
  Read of size 4 at addr ffff8801d3cc8bb4 by task syz-executor907/4466

This happens for any index_key_len which is not divisible by 4 and is
larger than the size of the inline key, because the code allocates exactly
index_key_len for the key buffer, but the hashing loop is stepping through
it 4 bytes (u32) at a time in the buf[] array.

Fix this by calculating how many u32 buffers we'll need by using
DIV_ROUND_UP, and then using kcalloc() to allocate a precleared allocation
buffer to hold the index_key, then using that same count as the hashing
index limit.

Fixes: ec0328e4

 ("fscache: Maintain a catalogue of allocated cookies")
Reported-by:  <syzbot+a95b989b2dde8e806af8@syzkaller.appspotmail.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The inline key in struct rxrpc_cookie is insufficiently initialized,
zeroing only 3 of the 4 slots, therefore an index_key_len between 13 and 15
bytes will end up hashing uninitialized memory because the memcpy only
partially fills the last buf[] element.

Fix this by clearing fscache_cookie objects on allocation rather than using
the slab constructor to initialise them.  We're going to pretty much fill
in the entire struct anyway, so bringing it into our dcache writably
shouldn't incur much overhead.

This removes the need to do clearance in fscache_set_key() (where we aren't
doing it correctly anyway).

Also, we don't need to set cookie->key_len in fscache_set_key() as we
already did it in the only caller, so remove that.

Fixes: ec0328e4

 ("fscache: Maintain a catalogue of allocated cookies")
Reported-by:  <syzbot+a95b989b2dde8e806af8@syzkaller.appspotmail.com>
Reported-by: Eric Sandeen <sandeen@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

the victim might've been rmdir'ed just before the lock_rename();
unlike the normal callers, we do not look the source up after the
parents are locked - we know it beforehand and just recheck that it's
still the child of what used to be its parent.  Unfortunately,
the check is too weak - we don't spot a dead directory since its
->d_parent is unchanged, dentry is positive, etc.  So we sail all
the way to ->rename(), with hosting filesystems _not_ expecting
to be asked renaming an rmdir'ed subdirectory.

The fix is easy, fortunately - the lock on parent is sufficient for
making IS_DEADDIR() on child safe.

Cc: stable@vger.kernel.org
Fixes: 9ae326a6

 (CacheFiles: A cache that backs onto a mounted filesystem)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Jann Horn points out that our TLB flushing was subtly wrong for the
mremap() case.  What makes mremap() special is that we don't follow the
usual "add page to list of pages to be freed, then flush tlb, and then
free pages".  No, mremap() obviously just _moves_ the page from one page
table location to another.

That matters, because mremap() thus doesn't directly control the
lifetime of the moved page with a freelist: instead, the lifetime of the
page is controlled by the page table locking, that serializes access to
the entry.

As a result, we need to flush the TLB not just before releasing the lock
for the source location (to avoid any concurrent accesses to the entry),
but also before we release the destination page table lock (to avoid the
TLB being flushed after somebody else has already done something to that
page).

This also makes the whole "need_flush" logic unnecessary, since we now
always end up flushing the TLB for every valid entry.

Reported-and-tested-by: Jann Horn <jannh@google.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Using non-GPL licenses for our documentation is rather problematic,
as it can directly include other files, which generally are GPLv2
licensed and thus not compatible.

Remove this license now that the only user (idr.rst) is gone to avoid
people semi-accidentally using it again.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Matthew writes:
  "IDA/IDR fixes for 4.19

   I have two tiny fixes, one for the IDA test-suite and one for the IDR
   documentation license."

* 'ida-fixes-4.19-rc8' of git://git.infradead.org/users/willy/linux-dax:
  idr: Change documentation license
  test_ida: Fix lockdep warning

If the skb space ends in an unresolved entry while dumping we'll miss
some unresolved entries. The reason is due to zeroing the entry counter
between dumping resolved and unresolved mfc entries. We should just
keep counting until the whole table is dumped and zero when we move to
the next as we have a separate table counter.

Reported-by: Colin Ian King <colin.king@canonical.com>
Fixes: 8fb472c0

 ("ipmr: improve hash scalability")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The ocelot_vlant_wait_for_completion() function is very similar to the
ocelot_mact_wait_for_completion(). It seemed to have be copied but the
comment was not updated, so let's fix it.

Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sctp data size should be calculated by subtracting data chunk header's
length from chunk_hdr->length, not just data header.

Fixes: 668c9beb

 ("sctp: implement assign_number for sctp_stream_interleave")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit 713a98d9 ("virtio-net: serialize tx routine during reset")
introduces netif_tx_disable() after netif_device_detach() in order to
avoid use-after-free of tx queues. However, there are two issues.

1) Its operation is redundant with netif_device_detach() in case the
   interface is running.
2) In case of the interface is not running before suspending and
   resuming, the tx does not get resumed by netif_device_attach().
   This results in losing network connectivity.

It is better to use netif_tx_lock_bh()/netif_tx_unlock_bh() instead for
serializing tx routine during reset. This also preserves the symmetry
of netif_device_detach() and netif_device_attach().

Fixes commit 713a98d9

 ("virtio-net: serialize tx routine during reset")
Signed-off-by: Ake Koomsin <ake@igel.co.jp>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Steven writes:
  "tracing: Two fixes for 4.19

   This fixes two bugs:
    - Fix size mismatch of tracepoint array
    - Have preemptirq test module use same clock source of the selftest"

* tag 'trace-v4.19-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Use trace_clock_local() for looping in preemptirq_delay_test.c
  tracepoint: Fix tracepoint array element size mismatch

The commit eb63f296 ("udp6: add missing checks on edumux packet
processing") used the same return code convention of the ipv4 counterpart,
but ipv6 uses the opposite one: positive values means resubmit.

This change addresses the issue, using positive return value for
resubmitting. Also update the related comment, which was broken, too.

Fixes: eb63f296

 ("udp6: add missing checks on edumux packet processing")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When the switch driver (e.g., mlxsw_spectrum) determines it needs to
flash a new firmware version it resets the ASIC after the flashing
process. The bus driver (e.g., mlxsw_pci) then registers itself again
with mlxsw_core which means (among other things) that the device
registers itself again with the hwmon subsystem again.

Since the device was registered with the hwmon subsystem using
devm_hwmon_device_register_with_groups(), then the old hwmon device
(registered before the flashing) was never unregistered and was
referencing stale data, resulting in a use-after free.

Fix by removing reliance on device managed APIs in mlxsw_hwmon_init().

Fixes: c86d62cc

 ("mlxsw: spectrum: Reset FW after flash")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reported-by: Alexander Petrovskiy <alexpe@mellanox.com>
Tested-by: Alexander Petrovskiy <alexpe@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When sctp_wait_for_connect is called to wait for connect ready
for sp->strm_interleave in sctp_sendmsg_to_asoc, a panic could
be triggered if cpu is scheduled out and the new asoc is freed
elsewhere, as it will return err and later the asoc gets freed
again in sctp_sendmsg.

[  285.840764] list_del corruption, ffff9f0f7b284078->next is LIST_POISON1 (dead000000000100)
[  285.843590] WARNING: CPU: 1 PID: 8861 at lib/list_debug.c:47 __list_del_entry_valid+0x50/0xa0
[  285.846193] Kernel panic - not syncing: panic_on_warn set ...
[  285.846193]
[  285.848206] CPU: 1 PID: 8861 Comm: sctp_ndata Kdump: loaded Not tainted 4.19.0-rc7.label #584
[  285.850559] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[  285.852164] Call Trace:
...
[  285.872210]  ? __list_del_entry_valid+0x50/0xa0
[  285.872894]  sctp_association_free+0x42/0x2d0 [sctp]
[  285.873612]  sctp_sendmsg+0x5a4/0x6b0 [sctp]
[  285.874236]  sock_sendmsg+0x30/0x40
[  285.874741]  ___sys_sendmsg+0x27a/0x290
[  285.875304]  ? __switch_to_asm+0x34/0x70
[  285.875872]  ? __switch_to_asm+0x40/0x70
[  285.876438]  ? ptep_set_access_flags+0x2a/0x30
[  285.877083]  ? do_wp_page+0x151/0x540
[  285.877614]  __sys_sendmsg+0x58/0xa0
[  285.878138]  do_syscall_64+0x55/0x180
[  285.878669]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

This is a similar issue with the one fixed in Commit ca3af4dd
("sctp: do not free asoc when it is already dead in sctp_sendmsg").
But this one can't be fixed by returning -ESRCH for the dead asoc
in sctp_wait_for_connect, as it will break sctp_connect's return
value to users.

This patch is to simply set err to -ESRCH before it returns to
sctp_sendmsg when any err is returned by sctp_wait_for_connect
for sp->strm_interleave, so that no asoc would be freed due to
this.

When users see this error, they will know the packet hasn't been
sent. And it also makes sense to not free asoc because waiting
connect fails, like the second call for sctp_wait_for_connect in
sctp_sendmsg_to_asoc.

Fixes: 668c9beb

 ("sctp: implement assign_number for sctp_stream_interleave")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

syzbot reported an use-after-free involving sctp_id2asoc.  Dmitry Vyukov
helped to root cause it and it is because of reading the asoc after it
was freed:

        CPU 1                       CPU 2
(working on socket 1)            (working on socket 2)
	                         sctp_association_destroy
sctp_id2asoc
   spin lock
     grab the asoc from idr
   spin unlock
                                   spin lock
				     remove asoc from idr
				   spin unlock
				   free(asoc)
   if asoc->base.sk != sk ... [*]

This can only be hit if trying to fetch asocs from different sockets. As
we have a single IDR for all asocs, in all SCTP sockets, their id is
unique on the system. An application can try to send stuff on an id
that matches on another socket, and the if in [*] will protect from such
usage. But it didn't consider that as that asoc may belong to another
socket, it may be freed in parallel (read: under another socket lock).

We fix it by moving the checks in [*] into the protected region. This
fixes it because the asoc cannot be freed while the lock is held.

Reported-by:  <syzbot+c7dd55d7aec49d48e49a@syzkaller.appspotmail.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Similar to d49c88d7 ("r8169: Enable MSI-X on RTL8106e") after
e9d0ba506ea8 ("PCI: Reprogram bridge prefetch registers on resume")
we can safely assume that this also fixes the root cause of
the issue worked around by 7c53a722 ("r8169: don't use MSI-X on
RTL8168g"). So let's revert it.

Fixes: 7c53a722

 ("r8169: don't use MSI-X on RTL8168g")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

pid_task() dereferences rcu protected tasks array.
But there is no rcu_read_lock() in shutdown_umh() routine so that
rcu_read_lock() is needed.
get_pid_task() is wrapper function of pid_task. it holds rcu_read_lock()
then calls pid_task(). if task isn't NULL, it increases reference count
of task.

test commands:
   %modprobe bpfilter
   %modprobe -rv bpfilter

splat looks like:
[15102.030932] =============================
[15102.030957] WARNING: suspicious RCU usage
[15102.030985] 4.19.0-rc7+ #21 Not tainted
[15102.031010] -----------------------------
[15102.031038] kernel/pid.c:330 suspicious rcu_dereference_check() usage!
[15102.031063]
	       other info that might help us debug this:

[15102.031332]
	       rcu_scheduler_active = 2, debug_locks = 1
[15102.031363] 1 lock held by modprobe/1570:
[15102.031389]  #0: 00000000580ef2b0 (bpfilter_lock){+.+.}, at: stop_umh+0x13/0x52 [bpfilter]
[15102.031552]
               stack backtrace:
[15102.031583] CPU: 1 PID: 1570 Comm: modprobe Not tainted 4.19.0-rc7+ #21
[15102.031607] Hardware name: To be filled by O.E.M. To be filled by O.E.M./Aptio CRB, BIOS 5.6.5 07/08/2015
[15102.031628] Call Trace:
[15102.031676]  dump_stack+0xc9/0x16b
[15102.031723]  ? show_regs_print_info+0x5/0x5
[15102.031801]  ? lockdep_rcu_suspicious+0x117/0x160
[15102.031855]  pid_task+0x134/0x160
[15102.031900]  ? find_vpid+0xf0/0xf0
[15102.032017]  shutdown_umh.constprop.1+0x1e/0x53 [bpfilter]
[15102.032055]  stop_umh+0x46/0x52 [bpfilter]
[15102.032092]  __x64_sys_delete_module+0x47e/0x570
[ ... ]

Fixes: d2ba09c1

 ("net: add skeleton of bpfilter kernel module")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

pin_index can be indirectly controlled by user-space, hence leading
to a potential exploitation of the Spectre variant 1 vulnerability.

This issue was detected with the help of Smatch:

drivers/ptp/ptp_chardev.c:253 ptp_ioctl() warn: potential spectre issue
'ops->pin_config' [r] (local cap)

Fix this by sanitizing pin_index before using it to index
ops->pin_config, and before passing it as an argument to
function ptp_set_pinfunc(), in which it is used to index
info->pin_config.

Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].

[1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2



Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Smatch complains that "val" would be uninitialized if kstrtoul() fails.

Fixes: 9a08862a

 ("vDSO for sparc")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Clang currently warns:

drivers/net/ethernet/qlogic/qla3xxx.c:384:24: warning: signed shift
result (0xF00000000) requires 37 bits to represent, but 'int' only has
32 bits [-Wshift-overflow]
                    ((ISP_NVRAM_MASK << 16) | qdev->eeprom_cmd_data));
                      ~~~~~~~~~~~~~~ ^  ~~
1 warning generated.

The warning is certainly accurate since ISP_NVRAM_MASK is defined as
(0x000F << 16) which is then shifted by 16, resulting in 64424509440,
well above UINT_MAX.

Given that this is the only location in this driver where ISP_NVRAM_MASK
is shifted again, it seems likely that ISP_NVRAM_MASK was originally
defined without a shift and during the move of the shift to the
definition, this statement wasn't properly removed (since ISP_NVRAM_MASK
is used in the statenent right above this). Only the maintainers can
confirm this since this statment has been here since the driver was
first added to the kernel.

Link: https://github.com/ClangBuiltLinux/linux/issues/127


Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>