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  1. 10 Jan, 2018 2 commits
    • Colin Ian King's avatar
      bpf: fix spelling mistake: "obusing" -> "abusing" · 40950343
      Colin Ian King authored 
      Trivial fix to spelling mistake in error message text.
Signed-off-by: default avatarColin Ian King <colin.king@canonical.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
      40950343
    • David S. Miller's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf · 661e4e33
      David S. Miller authored 
      Daniel Borkmann says:

====================
pull-request: bpf 2018-01-09

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Prevent out-of-bounds speculation in BPF maps by masking the
   index after bounds checks in order to fix spectre v1, and
   add an option BPF_JIT_ALWAYS_ON into Kconfig that allows for
   removing the BPF interpreter from the kernel in favor of
   JIT-only mode to make spectre v2 harder, from Alexei.

2) Remove false sharing of map refcount with max_entries which
   was used in spectre v1, from Daniel.

3) Add a missing NULL psock check in sockmap in order to fix
   a race, from John.

4) Fix test_align BPF selftest case since a recent change in
   verifier rejects the bit-wise arithmetic on pointers
   earlier but test_align update was missing, from Alexei.
====================
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      661e4e33
  3. 09 Jan, 2018 12 commits
    • Alexei Starovoitov's avatar
      bpf: introduce BPF_JIT_ALWAYS_ON config · 290af866
      Alexei Starovoitov authored 
      The BPF interpreter has been used as part of the spectre 2 attack CVE-2017-5715.

A quote from goolge project zero blog:
"At this point, it would normally be necessary to locate gadgets in
the host kernel code that can be used to actually leak data by reading
from an attacker-controlled location, shifting and masking the result
appropriately and then using the result of that as offset to an
attacker-controlled address for a load. But piecing gadgets together
and figuring out which ones work in a speculation context seems annoying.
So instead, we decided to use the eBPF interpreter, which is built into
the host kernel - while there is no legitimate way to invoke it from inside
a VM, the presence of the code in the host kernel's text section is sufficient
to make it usable for the attack, just like with ordinary ROP gadgets."

To make attacker job harder introduce BPF_JIT_ALWAYS_ON config
option that removes interpreter from the kernel in favor of JIT-only mode.
So far eBPF JIT is supported by:
x64, arm64, arm32, sparc64, s390, powerpc64, mips64

The start of JITed program is randomized and code page is marked as read-only.
In addition "constant blinding" can be turned on with net.core.bpf_jit_harden

v2->v3:
- move __bpf_prog_ret0 under ifdef (Daniel)

v1->v2:
- fix init order, test_bpf and cBPF (Daniel's feedback)
- fix offloaded bpf (Jakub's feedback)
- add 'return 0' dummy in case something can invoke prog->bpf_func
- retarget bpf tree. For bpf-next the patch would need one extra hunk.
  It will be sent when the trees are merged back to net-next

Considered doing:
  int bpf_jit_enable __read_mostly = BPF_EBPF_JIT_DEFAULT;
but it seems better to land the patch as-is and in bpf-next remove
bpf_jit_enable global variable from all JITs, consolidate in one place
and remove this jit_init() function.
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
      290af866
    • Daniel Borkmann's avatar
      bpf: avoid false sharing of map refcount with max_entries · be95a845
      Daniel Borkmann authored 
      In addition to commit b2157399 ("bpf: prevent out-of-bounds
speculation") also change the layout of struct bpf_map such that
false sharing of fast-path members like max_entries is avoided
when the maps reference counter is altered. Therefore enforce
them to be placed into separate cachelines.

pahole dump after change:

  struct bpf_map {
        const struct bpf_map_ops  * ops;                 /*     0     8 */
        struct bpf_map *           inner_map_meta;       /*     8     8 */
        void *                     security;             /*    16     8 */
        enum bpf_map_type          map_type;             /*    24     4 */
        u32                        key_size;             /*    28     4 */
        u32                        value_size;           /*    32     4 */
        u32                        max_entries;          /*    36     4 */
        u32                        map_flags;            /*    40     4 */
        u32                        pages;                /*    44     4 */
        u32                        id;                   /*    48     4 */
        int                        numa_node;            /*    52     4 */
        bool                       unpriv_array;         /*    56     1 */

        /* XXX 7 bytes hole, try to pack */

        /* --- cacheline 1 boundary (64 bytes) --- */
        struct user_struct *       user;                 /*    64     8 */
        atomic_t                   refcnt;               /*    72     4 */
        atomic_t                   usercnt;              /*    76     4 */
        struct work_struct         work;                 /*    80    32 */
        char                       name[16];             /*   112    16 */
        /* --- cacheline 2 boundary (128 bytes) --- */

        /* size: 128, cachelines: 2, members: 17 */
        /* sum members: 121, holes: 1, sum holes: 7 */
  };

Now all entries in the first cacheline are read only throughout
the life time of the map, set up once during map creation. Overall
struct size and number of cachelines doesn't change from the
reordering. struct bpf_map is usually first member and embedded
in map structs in specific map implementations, so also avoid those
members to sit at the end where it could potentially share the
cacheline with first map values e.g. in the array since remote
CPUs could trigger map updates just as well for those (easily
dirtying members like max_entries intentionally as well) while
having subsequent values in cache.

Quoting from Google's Project Zero blog [1]:

  Additionally, at least on the Intel machine on which this was
  tested, bouncing modified cache lines between cores is slow,
  apparently because the MESI protocol is used for cache coherence
  [8]. Changing the reference counter of an eBPF array on one
  physical CPU core causes the cache line containing the reference
  counter to be bounced over to that CPU core, making reads of the
  reference counter on all other CPU cores slow until the changed
  reference counter has been written back to memory. Because the
  length and the reference counter of an eBPF array are stored in
  the same cache line, this also means that changing the reference
  counter on one physical CPU core causes reads of the eBPF array's
  length to be slow on other physical CPU cores (intentional false
  sharing).

While this doesn't 'control' the out-of-bounds speculation through
masking the index as in commit b2157399, triggering a manipulation
of the map's reference counter is really trivial, so lets not allow
to easily affect max_entries from it.

Splitting to separate cachelines also generally makes sense from
a performance perspective anyway in that fast-path won't have a
cache miss if the map gets pinned, reused in other progs, etc out
of control path, thus also avoids unintentional false sharing.

  [1] https://googleprojectzero.blogspot.ch/2018/01/reading-privileged-memory-with-side.htmlSigned-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
      be95a845
    • Wei Wang's avatar
      ipv6: remove null_entry before adding default route · 4512c43e
      Wei Wang authored 
      In the current code, when creating a new fib6 table, tb6_root.leaf gets
initialized to net->ipv6.ip6_null_entry.
If a default route is being added with rt->rt6i_metric = 0xffffffff,
fib6_add() will add this route after net->ipv6.ip6_null_entry. As
null_entry is shared, it could cause problem.

In order to fix it, set fn->leaf to NULL before calling
fib6_add_rt2node() when trying to add the first default route.
And reset fn->leaf to null_entry when adding fails or when deleting the
last default route.

syzkaller reported the following issue which is fixed by this commit:

WARNING: suspicious RCU usage
4.15.0-rc5+ #171 Not tainted
-----------------------------
net/ipv6/ip6_fib.c:1702 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
4 locks held by swapper/0/0:
 #0:  ((&net->ipv6.ip6_fib_timer)){+.-.}, at: [<00000000d43f631b>] lockdep_copy_map include/linux/lockdep.h:178 [inline]
 #0:  ((&net->ipv6.ip6_fib_timer)){+.-.}, at: [<00000000d43f631b>] call_timer_fn+0x1c6/0x820 kernel/time/timer.c:1310
 #1:  (&(&net->ipv6.fib6_gc_lock)->rlock){+.-.}, at: [<000000002ff9d65c>] spin_lock_bh include/linux/spinlock.h:315 [inline]
 #1:  (&(&net->ipv6.fib6_gc_lock)->rlock){+.-.}, at: [<000000002ff9d65c>] fib6_run_gc+0x9d/0x3c0 net/ipv6/ip6_fib.c:2007
 #2:  (rcu_read_lock){....}, at: [<0000000091db762d>] __fib6_clean_all+0x0/0x3a0 net/ipv6/ip6_fib.c:1560
 #3:  (&(&tb->tb6_lock)->rlock){+.-.}, at: [<000000009e503581>] spin_lock_bh include/linux/spinlock.h:315 [inline]
 #3:  (&(&tb->tb6_lock)->rlock){+.-.}, at: [<000000009e503581>] __fib6_clean_all+0x1d0/0x3a0 net/ipv6/ip6_fib.c:1948

stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.15.0-rc5+ #171
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 lockdep_rcu_suspicious+0x123/0x170 kernel/locking/lockdep.c:4585
 fib6_del+0xcaa/0x11b0 net/ipv6/ip6_fib.c:1701
 fib6_clean_node+0x3aa/0x4f0 net/ipv6/ip6_fib.c:1892
 fib6_walk_continue+0x46c/0x8a0 net/ipv6/ip6_fib.c:1815
 fib6_walk+0x91/0xf0 net/ipv6/ip6_fib.c:1863
 fib6_clean_tree+0x1e6/0x340 net/ipv6/ip6_fib.c:1933
 __fib6_clean_all+0x1f4/0x3a0 net/ipv6/ip6_fib.c:1949
 fib6_clean_all net/ipv6/ip6_fib.c:1960 [inline]
 fib6_run_gc+0x16b/0x3c0 net/ipv6/ip6_fib.c:2016
 fib6_gc_timer_cb+0x20/0x30 net/ipv6/ip6_fib.c:2033
 call_timer_fn+0x228/0x820 kernel/time/timer.c:1320
 expire_timers kernel/time/timer.c:1357 [inline]
 __run_timers+0x7ee/0xb70 kernel/time/timer.c:1660
 run_timer_softirq+0x4c/0xb0 kernel/time/timer.c:1686
 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285
 invoke_softirq kernel/softirq.c:365 [inline]
 irq_exit+0x1cc/0x200 kernel/softirq.c:405
 exiting_irq arch/x86/include/asm/apic.h:540 [inline]
 smp_apic_timer_interrupt+0x16b/0x700 arch/x86/kernel/apic/apic.c:1052
 apic_timer_interrupt+0xa9/0xb0 arch/x86/entry/entry_64.S:904
 </IRQ>
Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
Fixes: 66f5d6ce ("ipv6: replace rwlock with rcu and spinlock in fib6_table")
Signed-off-by: default avatarWei Wang <weiwan@google.com>
Acked-by: default avatarMartin KaFai Lau <kafai@fb.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4512c43e
    • David S. Miller's avatar
      Merge branch 'Ether-fixes-for-the-SolutionEngine771x-boards' · 22dd8e6b
      David S. Miller authored 
      Sergei Shtylyov says:

====================
Ether fixes for the SolutionEngine771x boards

Here's the series of 2 patches against Linus' repo. This series should
(hoplefully) fix the Ether support on the SolutionEngine771x boards...

[1/2] SolutionEngine771x: fix Ether platform data
[2/2] SolutionEngine771x: add Ether TSU resource
====================
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      22dd8e6b
    • Sergei Shtylyov's avatar
      SolutionEngine771x: add Ether TSU resource · f9a531d6
      Sergei Shtylyov authored 
      After the  Ether platform data is fixed, the driver probe() method would
still fail since the 'struct sh_eth_cpu_data' corresponding  to SH771x
indicates the presence of TSU but the memory resource for it is absent.
Add the missing TSU resource  to both Ether devices and fix the harmless
off-by-one error in the main memory resources, while at it...

Fixes: 4986b996 ("net: sh_eth: remove the SH_TSU_ADDR")
Signed-off-by: default avatarSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      f9a531d6
    • Sergei Shtylyov's avatar
      SolutionEngine771x: fix Ether platform data · 195e2add
      Sergei Shtylyov authored 
      The 'sh_eth' driver's probe() method would fail  on the SolutionEngine7710
board and crash on SolutionEngine7712 board  as the platform code is
hopelessly behind the driver's platform data --  it passes the PHY address
instead of 'struct sh_eth_plat_data *'; pass the latter to the driver in
order to fix the bug...

Fixes: 71557a37 ("[netdrvr] sh_eth: Add SH7619 support")
Signed-off-by: default avatarSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      195e2add
    • Mike Rapoport's avatar
      docs-rst: networking: wire up msg_zerocopy · 2fdd1811
      Mike Rapoport authored 
      Fix the following 'make htmldocs' complaint:

Documentation/networking/msg_zerocopy.rst:: WARNING: document isn't included in any toctree.
Signed-off-by: default avatarMike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      2fdd1811
    • Nicolai Stange's avatar
      net: ipv4: emulate READ_ONCE() on ->hdrincl bit-field in raw_sendmsg() · 20b50d79
      Nicolai Stange authored 
      Commit 8f659a03 ("net: ipv4: fix for a race condition in
raw_sendmsg") fixed the issue of possibly inconsistent ->hdrincl handling
due to concurrent updates by reading this bit-field member into a local
variable and using the thus stabilized value in subsequent tests.

However, aforementioned commit also adds the (correct) comment that

  /* hdrincl should be READ_ONCE(inet->hdrincl)
   * but READ_ONCE() doesn't work with bit fields
   */

because as it stands, the compiler is free to shortcut or even eliminate
the local variable at its will.

Note that I have not seen anything like this happening in reality and thus,
the concern is a theoretical one.

However, in order to be on the safe side, emulate a READ_ONCE() on the
bit-field by doing it on the local 'hdrincl' variable itself:

	int hdrincl = inet->hdrincl;
	hdrincl = READ_ONCE(hdrincl);

This breaks the chain in the sense that the compiler is not allowed
to replace subsequent reads from hdrincl with reloads from inet->hdrincl.

Fixes: 8f659a03 ("net: ipv4: fix for a race condition in raw_sendmsg")
Signed-off-by: default avatarNicolai Stange <nstange@suse.de>
Reviewed-by: default avatarStefano Brivio <sbrivio@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      20b50d79
    • Xiongfeng Wang's avatar
      net: caif: use strlcpy() instead of strncpy() · 3dc2fa47
      Xiongfeng Wang authored 
      gcc-8 reports

net/caif/caif_dev.c: In function 'caif_enroll_dev':
./include/linux/string.h:245:9: warning: '__builtin_strncpy' output may
be truncated copying 15 bytes from a string of length 15
[-Wstringop-truncation]

net/caif/cfctrl.c: In function 'cfctrl_linkup_request':
./include/linux/string.h:245:9: warning: '__builtin_strncpy' output may
be truncated copying 15 bytes from a string of length 15
[-Wstringop-truncation]

net/caif/cfcnfg.c: In function 'caif_connect_client':
./include/linux/string.h:245:9: warning: '__builtin_strncpy' output may
be truncated copying 15 bytes from a string of length 15
[-Wstringop-truncation]

The compiler require that the input param 'len' of strncpy() should be
greater than the length of the src string, so that '\0' is copied as
well. We can just use strlcpy() to avoid this warning.
Signed-off-by: default avatarXiongfeng Wang <xiongfeng.wang@linaro.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      3dc2fa47
    • Andrii Vladyka's avatar
      net: core: fix module type in sock_diag_bind · b8fd0823
      Andrii Vladyka authored 
      Use AF_INET6 instead of AF_INET in IPv6-related code path
Signed-off-by: default avatarAndrii Vladyka <tulup@mail.ru>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b8fd0823
    • Linus Torvalds's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net · ef7f8cec
      Linus Torvalds authored 
      Pull networking fixes from David Miller:

 1) Frag and UDP handling fixes in i40e driver, from Amritha Nambiar and
    Alexander Duyck.

 2) Undo unintentional UAPI change in netfilter conntrack, from Florian
    Westphal.

 3) Revert a change to how error codes are returned from
    dev_get_valid_name(), it broke some apps.

 4) Cannot cache routes for ipv6 tunnels in the tunnel is ipv4/ipv6
    dual-stack. From Eli Cooper.

 5) Fix missed PMTU updates in geneve, from Xin Long.

 6) Cure double free in macvlan, from Gao Feng.

 7) Fix heap out-of-bounds write in rds_message_alloc_sgs(), from
    Mohamed Ghannam.

 8) FEC bug fixes from FUgang Duan (mis-accounting of dev_id, missed
    deferral of probe when the regulator is not ready yet).

 9) Missing DMA mapping error checks in 3c59x, from Neil Horman.

10) Turn off Broadcom tags for some b53 switches, from Florian Fainelli.

11) Fix OOPS when get_target_net() is passed an SKB whose NETLINK_CB()
    isn't initialized. From Andrei Vagin.

12) Fix crashes in fib6_add(), from Wei Wang.

13) PMTU bug fixes in SCTP from Marcelo Ricardo Leitner.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (56 commits)
  sh_eth: fix TXALCR1 offsets
  mdio-sun4i: Fix a memory leak
  phylink: mark expected switch fall-throughs in phylink_mii_ioctl
  sctp: fix the handling of ICMP Frag Needed for too small MTUs
  sctp: do not retransmit upon FragNeeded if PMTU discovery is disabled
  xen-netfront: enable device after manual module load
  bnxt_en: Fix the 'Invalid VF' id check in bnxt_vf_ndo_prep routine.
  bnxt_en: Fix population of flow_type in bnxt_hwrm_cfa_flow_alloc()
  sh_eth: fix SH7757 GEther initialization
  net: fec: free/restore resource in related probe error pathes
  uapi/if_ether.h: prevent redefinition of struct ethhdr
  ipv6: fix general protection fault in fib6_add()
  RDS: null pointer dereference in rds_atomic_free_op
  sh_eth: fix TSU resource handling
  net: stmmac: enable EEE in MII, GMII or RGMII only
  rtnetlink: give a user socket to get_target_net()
  MAINTAINERS: Update my email address.
  can: ems_usb: improve error reporting for error warning and error passive
  can: flex_can: Correct the checking for frame length in flexcan_start_xmit()
  can: gs_usb: fix return value of the "set_bittiming" callback
  ...
      ef7f8cec
    • Linus Torvalds's avatar
      Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma · 44596f86
      Linus Torvalds authored 
      Pull rdma fixes from Doug Ledford:

 - One line fix to mlx4 error flow (same as mlx5 fix in last pull
   request, just in the mlx4 driver)

 - Fix a race condition in the IPoIB driver. This patch is larger than
   just a one line fix, but resolves a race condition in a fairly
   straight forward manner

 - Fix a locking issue in the RDMA netlink code. This patch is also
   larger than I would like for a late -rc. It has, however, had a week
   to bake in the rdma tree prior to this pull request

 - One line fix to fix granting remote machine access to memory that
   they don't need and shouldn't have

 - One line fix to correct the fact that our sgid/dgid pair is swapped
   from what you would expect when receiving an incoming connection
   request

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  IB/srpt: Fix ACL lookup during login
  IB/srpt: Disable RDMA access by the initiator
  RDMA/netlink: Fix locking around __ib_get_device_by_index
  IB/ipoib: Fix race condition in neigh creation
  IB/mlx4: Fix mlx4_ib_alloc_mr error flow
      44596f86
  5. 08 Jan, 2018 14 commits
  7. 07 Jan, 2018 8 commits
  9. 06 Jan, 2018 4 commits
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