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  1. 19 Oct, 2017 10 commits
  3. 18 Oct, 2017 4 commits
    • Jakub Kicinski's avatar
      bpf: disallow arithmetic operations on context pointer · 28e33f9d
      Jakub Kicinski authored 
      Commit f1174f77 ("bpf/verifier: rework value tracking")
removed the crafty selection of which pointer types are
allowed to be modified.  This is OK for most pointer types
since adjust_ptr_min_max_vals() will catch operations on
immutable pointers.  One exception is PTR_TO_CTX which is
now allowed to be offseted freely.

The intent of aforementioned commit was to allow context
access via modified registers.  The offset passed to
->is_valid_access() verifier callback has been adjusted
by the value of the variable offset.

What is missing, however, is taking the variable offset
into account when the context register is used.  Or in terms
of the code adding the offset to the value passed to the
->convert_ctx_access() callback.  This leads to the following
eBPF user code:

     r1 += 68
     r0 = *(u32 *)(r1 + 8)
     exit

being translated to this in kernel space:

   0: (07) r1 += 68
   1: (61) r0 = *(u32 *)(r1 +180)
   2: (95) exit

Offset 8 is corresponding to 180 in the kernel, but offset
76 is valid too.  Verifier will "accept" access to offset
68+8=76 but then "convert" access to offset 8 as 180.
Effective access to offset 248 is beyond the kernel context.
(This is a __sk_buff example on a debug-heavy kernel -
packet mark is 8 -> 180, 76 would be data.)

Dereferencing the modified context pointer is not as easy
as dereferencing other types, because we have to translate
the access to reading a field in kernel structures which is
usually at a different offset and often of a different size.
To allow modifying the pointer we would have to make sure
that given eBPF instruction will always access the same
field or the fields accessed are "compatible" in terms of
offset and size...

Disallow dereferencing modified context pointers and add
to selftests the test case described here.

Fixes: f1174f77 ("bpf/verifier: rework value tracking")
Signed-off-by: default avatarJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarAlexei Starovoitov <ast@kernel.org>
Acked-by: default avatarEdward Cree <ecree@solarflare.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      28e33f9d
    • Johannes Berg's avatar
      netlink: fix netlink_ack() extack race · 48044eb4
      Johannes Berg authored 
      It seems that it's possible to toggle NETLINK_F_EXT_ACK
through setsockopt() while another thread/CPU is building
a message inside netlink_ack(), which could then trigger
the WARN_ON()s I added since if it goes from being turned
off to being turned on between allocating and filling the
message, the skb could end up being too small.

Avoid this whole situation by storing the value of this
flag in a separate variable and using that throughout the
function instead.

Fixes: 2d4bc933 ("netlink: extended ACK reporting")
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      48044eb4
    • Thomas Falcon's avatar
      ibmvnic: Fix calculation of number of TX header descriptors · 2de09681
      Thomas Falcon authored 
      This patch correctly sets the number of additional header descriptors
that will be sent in an indirect SCRQ entry.
Signed-off-by: default avatarThomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      2de09681
    • Ido Schimmel's avatar
      mlxsw: core: Fix possible deadlock · d965465b
      Ido Schimmel authored 
      When an EMAD is transmitted, a timeout work item is scheduled with a
delay of 200ms, so that another EMAD will be retried until a maximum of
five retries.

In certain situations, it's possible for the function waiting on the
EMAD to be associated with a work item that is queued on the same
workqueue (`mlxsw_core`) as the timeout work item. This results in
flushing a work item on the same workqueue.

According to commit e159489b ("workqueue: relax lockdep annotation
on flush_work()") the above may lead to a deadlock in case the workqueue
has only one worker active or if the system in under memory pressure and
the rescue worker is in use. The latter explains the very rare and
random nature of the lockdep splats we have been seeing:

[   52.730240] ============================================
[   52.736179] WARNING: possible recursive locking detected
[   52.742119] 4.14.0-rc3jiri+ #4 Not tainted
[   52.746697] --------------------------------------------
[   52.752635] kworker/1:3/599 is trying to acquire lock:
[   52.758378]  (mlxsw_core_driver_name){+.+.}, at: [<ffffffff811c4fa4>] flush_work+0x3a4/0x5e0
[   52.767837]
               but task is already holding lock:
[   52.774360]  (mlxsw_core_driver_name){+.+.}, at: [<ffffffff811c65c4>] process_one_work+0x7d4/0x12f0
[   52.784495]
               other info that might help us debug this:
[   52.791794]  Possible unsafe locking scenario:
[   52.798413]        CPU0
[   52.801144]        ----
[   52.803875]   lock(mlxsw_core_driver_name);
[   52.808556]   lock(mlxsw_core_driver_name);
[   52.813236]
                *** DEADLOCK ***
[   52.819857]  May be due to missing lock nesting notation
[   52.827450] 3 locks held by kworker/1:3/599:
[   52.832221]  #0:  (mlxsw_core_driver_name){+.+.}, at: [<ffffffff811c65c4>] process_one_work+0x7d4/0x12f0
[   52.842846]  #1:  ((&(&bridge->fdb_notify.dw)->work)){+.+.}, at: [<ffffffff811c65c4>] process_one_work+0x7d4/0x12f0
[   52.854537]  #2:  (rtnl_mutex){+.+.}, at: [<ffffffff822ad8e7>] rtnl_lock+0x17/0x20
[   52.863021]
               stack backtrace:
[   52.867890] CPU: 1 PID: 599 Comm: kworker/1:3 Not tainted 4.14.0-rc3jiri+ #4
[   52.875773] Hardware name: Mellanox Technologies Ltd. "MSN2100-CB2F"/"SA001017", BIOS 5.6.5 06/07/2016
[   52.886267] Workqueue: mlxsw_core mlxsw_sp_fdb_notify_work [mlxsw_spectrum]
[   52.894060] Call Trace:
[   52.909122]  __lock_acquire+0xf6f/0x2a10
[   53.025412]  lock_acquire+0x158/0x440
[   53.047557]  flush_work+0x3c4/0x5e0
[   53.087571]  __cancel_work_timer+0x3ca/0x5e0
[   53.177051]  cancel_delayed_work_sync+0x13/0x20
[   53.182142]  mlxsw_reg_trans_bulk_wait+0x12d/0x7a0 [mlxsw_core]
[   53.194571]  mlxsw_core_reg_access+0x586/0x990 [mlxsw_core]
[   53.225365]  mlxsw_reg_query+0x10/0x20 [mlxsw_core]
[   53.230882]  mlxsw_sp_fdb_notify_work+0x2a3/0x9d0 [mlxsw_spectrum]
[   53.237801]  process_one_work+0x8f1/0x12f0
[   53.321804]  worker_thread+0x1fd/0x10c0
[   53.435158]  kthread+0x28e/0x370
[   53.448703]  ret_from_fork+0x2a/0x40
[   53.453017] mlxsw_spectrum 0000:01:00.0: EMAD retries (2/5) (tid=bf4549b100000774)
[   53.453119] mlxsw_spectrum 0000:01:00.0: EMAD retries (5/5) (tid=bf4549b100000770)
[   53.453132] mlxsw_spectrum 0000:01:00.0: EMAD reg access failed (tid=bf4549b100000770,reg_id=200b(sfn),type=query,status=0(operation performed))
[   53.453143] mlxsw_spectrum 0000:01:00.0: Failed to get FDB notifications

Fix this by creating another workqueue for EMAD timeouts, thereby
preventing the situation of a work item trying to flush a work item
queued on the same workqueue.

Fixes: caf7297e ("mlxsw: core: Introduce support for asynchronous EMAD register access")
Signed-off-by: default avatarIdo Schimmel <idosch@mellanox.com>
Reported-by: default avatarJiri Pirko <jiri@mellanox.com>
Signed-off-by: default avatarJiri Pirko <jiri@mellanox.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      d965465b
  5. 16 Oct, 2017 13 commits
  7. 15 Oct, 2017 10 commits
  9. 13 Oct, 2017 3 commits
    • Emiliano Ingrassia's avatar
      net: stmmac: dwmac_lib: fix interchanged sleep/timeout values in DMA reset function · b9849860
      Emiliano Ingrassia authored 
      The DMA reset timeout, used in read_poll_timeout, is
ten times shorter than the sleep time.
This patch fixes these values interchanging them, as it was
before the read_poll_timeout introduction.

Fixes: 8a70aeca ("net: stmmac: Use readl_poll_timeout")
Signed-off-by: default avatarEmiliano Ingrassia <ingrassia@epigenesys.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b9849860
    • Arnd Bergmann's avatar
      liquidio: fix timespec64_to_ns typo · e7ad9793
      Arnd Bergmann authored 
      While experimenting with changes to the timekeeping code, I
ran into a build error in the liquidio driver:

drivers/net/ethernet/cavium/liquidio/lio_main.c: In function 'liquidio_ptp_settime':
drivers/net/ethernet/cavium/liquidio/lio_main.c:1850:22: error: passing argument 1 of 'timespec_to_ns' from incompatible pointer type [-Werror=incompatible-pointer-types]

The driver had a type mismatch since it was first merged, but
this never caused problems because it is only built on 64-bit
architectures that define timespec and timespec64 to the same
type.

If we ever want to compile-test the driver on 32-bit or change
the way that 64-bit timespec64 is defined, we need to fix it,
so let's just do it now.

Fixes: f21fb3ed ("Add support of Cavium Liquidio ethernet adapters")
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Acked-by: default avatarFelix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e7ad9793
    • David S. Miller's avatar
      Merge tag 'wireless-drivers-for-davem-2017-10-13' of... · db5972c9
      David S. Miller authored 
      Merge tag 'wireless-drivers-for-davem-2017-10-13' of git://git.kernel.org/pub/scm/linux/kernel/git/kvalo/wireless-drivers

Kalle Valo says:

====================
wireless-drivers fixes for 4.14

Nothing really special standing out, all of these are important fixes
which should go to 4.14.

iwlwifi

* fix support for 3168 device series

* fix a potential crash when using FW debugging recording;

* improve channel flags parsing to avoid warnings on too long traces

* return -ENODATA when the temperature is not available, since the
 -EIO we were returning was causing fatal errors in userspace

* avoid printing too many messages in dmesg when using monitor mode,
  since this can become very noisy and completely flood the logs

brcmsmac

* reduce stack usage to avoid frame size warnings with KASAN

brcmfmac

* add a check to avoid copying uninitialised memory

rtlwifi:

* fix a regression with rtl8821ae starting from v4.11 where
  connections was frequently lost
====================
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      db5972c9
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