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  1. 06 4月, 2017 3 次提交
  3. 05 4月, 2017 6 次提交
  5. 04 4月, 2017 3 次提交
    • M
      tcp: minimize false-positives on TCP/GRO check · 0b9aefea
      由 Marcelo Ricardo Leitner 提交于 
      Markus Trippelsdorf reported that after commit dcb17d22 ("tcp: warn
on bogus MSS and try to amend it") the kernel started logging the
warning for a NIC driver that doesn't even support GRO.

It was diagnosed that it was possibly caused on connections that were
using TCP Timestamps but some packets lacked the Timestamps option. As
we reduce rcv_mss when timestamps are used, the lack of them would cause
the packets to be bigger than expected, although this is a valid case.

As this warning is more as a hint, getting a clean-cut on the
threshold is probably not worth the execution time spent on it. This
patch thus alleviates the false-positives with 2 quick checks: by
accounting for the entire TCP option space and also checking against the
interface MTU if it's available.

These changes, specially the MTU one, might mask some real positives,
though if they are really happening, it's possible that sooner or later
it will be triggered anyway.
Reported-by: NMarkus Trippelsdorf <markus@trippelsdorf.de>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      0b9aefea
    • X
      sctp: check for dst and pathmtu update in sctp_packet_config · df2729c3
      由 Xin Long 提交于 
      This patch is to move sctp_transport_dst_check into sctp_packet_config
from sctp_packet_transmit and add pathmtu check in sctp_packet_config.

With this fix, sctp can update dst or pathmtu before appending chunks,
which can void dropping packets in sctp_packet_transmit when dst is
obsolete or dst's mtu is changed.

This patch is also to improve some other codes in sctp_packet_config.
It updates packet max_size with gso_max_size, checks for dst and
pathmtu, and appends ecne chunk only when packet is empty and asoc
is not NULL.

It makes sctp flush work better, as we only need to set up them once
for one flush schedule. It's also safe, since asoc is NULL only when
the packet is created by sctp_ootb_pkt_new in which it just gets the
new dst, no need to do more things for it other than set packet with
transport's pathmtu.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      df2729c3
    • S
      flow dissector: correct size of storage for ARP · ac6a3722
      由 Simon Horman 提交于 
      The last argument to __skb_header_pointer() should be a buffer large
enough to store struct arphdr. This can be a pointer to a struct arphdr
structure. The code was previously using a pointer to a pointer to
struct arphdr.

By my counting the storage available both before and after is 8 bytes on
x86_64.

Fixes: 55733350 ("flow disector: ARP support")
Reported-by: NNicolas Iooss <nicolas.iooss_linux@m4x.org>
Signed-off-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      ac6a3722
  7. 03 4月, 2017 1 次提交
  9. 02 4月, 2017 16 次提交
    • D
      Merge branch 'l2tp_session_find-fixes' · e5c1e519
      由 David S. Miller 提交于 
      Guillaume Nault says:

====================
l2tp: fix usage of l2tp_session_find()

l2tp_session_find() doesn't take a reference on the session returned to
its caller. Virtually all l2tp_session_find() users are racy, either
because the session can disappear from under them or because they take
a reference too late. This leads to bugs like 'use after free' or
failure to notice duplicate session creations.

In some cases, taking a reference on the session is not enough. The
special callbacks .ref() and .deref() also have to be called in cases
where the PPP pseudo-wire uses the socket associated with the session.
Therefore, when looking up a session, we also have to pass a flag
indicating if the .ref() callback has to be called.

In the future, we probably could drop the .ref() and .deref() callbacks
entirely by protecting the .sock field of struct pppol2tp_session with
RCU, thus allowing it to be freed and set to NULL even if the L2TP
session is still alive.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      e5c1e519
    • G
      l2tp: take a reference on sessions used in genetlink handlers · 2777e2ab
      由 Guillaume Nault 提交于 
      Callers of l2tp_nl_session_find() need to hold a reference on the
returned session since there's no guarantee that it isn't going to
disappear from under them.

Relying on the fact that no l2tp netlink message may be processed
concurrently isn't enough: sessions can be deleted by other means
(e.g. by closing the PPPOL2TP socket of a ppp pseudowire).

l2tp_nl_cmd_session_delete() is a bit special: it runs a callback
function that may require a previous call to session->ref(). In
particular, for ppp pseudowires, the callback is l2tp_session_delete(),
which then calls pppol2tp_session_close() and dereferences the PPPOL2TP
socket. The socket might already be gone at the moment
l2tp_session_delete() calls session->ref(), so we need to take a
reference during the session lookup. So we need to pass the do_ref
variable down to l2tp_session_get() and l2tp_session_get_by_ifname().

Since all callers have to be updated, l2tp_session_find_by_ifname() and
l2tp_nl_session_find() are renamed to reflect their new behaviour.

Fixes: 309795f4 ("l2tp: Add netlink control API for L2TP")
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2777e2ab
    • G
      l2tp: hold session while sending creation notifications · 5e6a9e5a
      由 Guillaume Nault 提交于 
      l2tp_session_find() doesn't take any reference on the returned session.
Therefore, the session may disappear while sending the notification.

Use l2tp_session_get() instead and decrement session's refcount once
the notification is sent.

Fixes: 33f72e6f ("l2tp : multicast notification to the registered listeners")
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      5e6a9e5a
    • G
      l2tp: fix duplicate session creation · dbdbc73b
      由 Guillaume Nault 提交于 
      l2tp_session_create() relies on its caller for checking for duplicate
sessions. This is racy since a session can be concurrently inserted
after the caller's verification.

Fix this by letting l2tp_session_create() verify sessions uniqueness
upon insertion. Callers need to be adapted to check for
l2tp_session_create()'s return code instead of calling
l2tp_session_find().

pppol2tp_connect() is a bit special because it has to work on existing
sessions (if they're not connected) or to create a new session if none
is found. When acting on a preexisting session, a reference must be
held or it could go away on us. So we have to use l2tp_session_get()
instead of l2tp_session_find() and drop the reference before exiting.

Fixes: d9e31d17 ("l2tp: Add L2TP ethernet pseudowire support")
Fixes: fd558d18 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts")
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      dbdbc73b
    • G
      l2tp: ensure session can't get removed during pppol2tp_session_ioctl() · 57377d63
      由 Guillaume Nault 提交于 
      Holding a reference on session is required before calling
pppol2tp_session_ioctl(). The session could get freed while processing the
ioctl otherwise. Since pppol2tp_session_ioctl() uses the session's socket,
we also need to take a reference on it in l2tp_session_get().

Fixes: fd558d18 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts")
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      57377d63
    • G
      l2tp: fix race in l2tp_recv_common() · 61b9a047
      由 Guillaume Nault 提交于 
      Taking a reference on sessions in l2tp_recv_common() is racy; this
has to be done by the callers.

To this end, a new function is required (l2tp_session_get()) to
atomically lookup a session and take a reference on it. Callers then
have to manually drop this reference.

Fixes: fd558d18 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts")
Signed-off-by: NGuillaume Nault <g.nault@alphalink.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      61b9a047
    • X
      sctp: use right in and out stream cnt · afe89962
      由 Xin Long 提交于 
      Since sctp reconf was added in sctp, the real cnt of in/out stream
have not been c.sinit_max_instreams and c.sinit_num_ostreams any
more.

This patch is to replace them with stream->in/outcnt.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      afe89962
    • D
      Merge tag 'mac80211-for-davem-2017-03-31' of... · 612307c6
      由 David S. Miller 提交于 
      Merge tag 'mac80211-for-davem-2017-03-31' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

Johannes Berg says:

====================
Two fixes:
 * don't block netdev queues (indefinitely!) if mac80211
   manages traffic queueing itself
 * check wiphy registration before checking for ops
   on resume, to avoid crash
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      612307c6
    • D
      Merge branch 'bpf-map_value_adj-reg-types-fixes' · 0989bd03
      由 David S. Miller 提交于 
      Daniel Borkmann says:

====================
BPF fixes on map_value_adj reg types

This set adds two fixes for map_value_adj register type in the
verifier and user space tests along with them for the BPF self
test suite. For details, please see individual patches.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      0989bd03
    • D
      bpf: add various verifier test cases for self-tests · 02ea80b1
      由 Daniel Borkmann 提交于 
      Add a couple of test cases, for example, probing for xadd on a spilled
pointer to packet and map_value_adj register, various other map_value_adj
tests including the unaligned load/store, and trying out pointer arithmetic
on map_value_adj register itself. For the unaligned load/store, we need
to figure out whether the architecture has efficient unaligned access and
need to mark affected tests accordingly.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      02ea80b1
    • D
      bpf, verifier: fix rejection of unaligned access checks for map_value_adj · 79adffcd
      由 Daniel Borkmann 提交于 
      Currently, the verifier doesn't reject unaligned access for map_value_adj
register types. Commit 48461135 ("bpf: allow access into map value
arrays") added logic to check_ptr_alignment() extending it from PTR_TO_PACKET
to also PTR_TO_MAP_VALUE_ADJ, but for PTR_TO_MAP_VALUE_ADJ no enforcement
is in place, because reg->id for PTR_TO_MAP_VALUE_ADJ reg types is never
non-zero, meaning, we can cause BPF_H/_W/_DW-based unaligned access for
architectures not supporting efficient unaligned access, and thus worst
case could raise exceptions on some archs that are unable to correct the
unaligned access or perform a different memory access to the actual
requested one and such.

i) Unaligned load with !CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
   on r0 (map_value_adj):

   0: (bf) r2 = r10
   1: (07) r2 += -8
   2: (7a) *(u64 *)(r2 +0) = 0
   3: (18) r1 = 0x42533a00
   5: (85) call bpf_map_lookup_elem#1
   6: (15) if r0 == 0x0 goto pc+11
    R0=map_value(ks=8,vs=48,id=0),min_value=0,max_value=0 R10=fp
   7: (61) r1 = *(u32 *)(r0 +0)
   8: (35) if r1 >= 0xb goto pc+9
    R0=map_value(ks=8,vs=48,id=0),min_value=0,max_value=0 R1=inv,min_value=0,max_value=10 R10=fp
   9: (07) r0 += 3
  10: (79) r7 = *(u64 *)(r0 +0)
    R0=map_value_adj(ks=8,vs=48,id=0),min_value=3,max_value=3 R1=inv,min_value=0,max_value=10 R10=fp
  11: (79) r7 = *(u64 *)(r0 +2)
    R0=map_value_adj(ks=8,vs=48,id=0),min_value=3,max_value=3 R1=inv,min_value=0,max_value=10 R7=inv R10=fp
  [...]

ii) Unaligned store with !CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
    on r0 (map_value_adj):

   0: (bf) r2 = r10
   1: (07) r2 += -8
   2: (7a) *(u64 *)(r2 +0) = 0
   3: (18) r1 = 0x4df16a00
   5: (85) call bpf_map_lookup_elem#1
   6: (15) if r0 == 0x0 goto pc+19
    R0=map_value(ks=8,vs=48,id=0),min_value=0,max_value=0 R10=fp
   7: (07) r0 += 3
   8: (7a) *(u64 *)(r0 +0) = 42
    R0=map_value_adj(ks=8,vs=48,id=0),min_value=3,max_value=3 R10=fp
   9: (7a) *(u64 *)(r0 +2) = 43
    R0=map_value_adj(ks=8,vs=48,id=0),min_value=3,max_value=3 R10=fp
  10: (7a) *(u64 *)(r0 -2) = 44
    R0=map_value_adj(ks=8,vs=48,id=0),min_value=3,max_value=3 R10=fp
  [...]

For the PTR_TO_PACKET type, reg->id is initially zero when skb->data
was fetched, it later receives a reg->id from env->id_gen generator
once another register with UNKNOWN_VALUE type was added to it via
check_packet_ptr_add(). The purpose of this reg->id is twofold: i) it
is used in find_good_pkt_pointers() for setting the allowed access
range for regs with PTR_TO_PACKET of same id once verifier matched
on data/data_end tests, and ii) for check_ptr_alignment() to determine
that when not having efficient unaligned access and register with
UNKNOWN_VALUE was added to PTR_TO_PACKET, that we're only allowed
to access the content bytewise due to unknown unalignment. reg->id
was never intended for PTR_TO_MAP_VALUE{,_ADJ} types and thus is
always zero, the only marking is in PTR_TO_MAP_VALUE_OR_NULL that
was added after 48461135 via 57a09bf0 ("bpf: Detect identical
PTR_TO_MAP_VALUE_OR_NULL registers"). Above tests will fail for
non-root environment due to prohibited pointer arithmetic.

The fix splits register-type specific checks into their own helper
instead of keeping them combined, so we don't run into a similar
issue in future once we extend check_ptr_alignment() further and
forget to add reg->type checks for some of the checks.

Fixes: 48461135 ("bpf: allow access into map value arrays")
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      79adffcd
    • D
      bpf, verifier: fix alu ops against map_value{, _adj} register types · fce366a9
      由 Daniel Borkmann 提交于 
      While looking into map_value_adj, I noticed that alu operations
directly on the map_value() resp. map_value_adj() register (any
alu operation on a map_value() register will turn it into a
map_value_adj() typed register) are not sufficiently protected
against some of the operations. Two non-exhaustive examples are
provided that the verifier needs to reject:

 i) BPF_AND on r0 (map_value_adj):

  0: (bf) r2 = r10
  1: (07) r2 += -8
  2: (7a) *(u64 *)(r2 +0) = 0
  3: (18) r1 = 0xbf842a00
  5: (85) call bpf_map_lookup_elem#1
  6: (15) if r0 == 0x0 goto pc+2
   R0=map_value(ks=8,vs=48,id=0),min_value=0,max_value=0 R10=fp
  7: (57) r0 &= 8
  8: (7a) *(u64 *)(r0 +0) = 22
   R0=map_value_adj(ks=8,vs=48,id=0),min_value=0,max_value=8 R10=fp
  9: (95) exit

  from 6 to 9: R0=inv,min_value=0,max_value=0 R10=fp
  9: (95) exit
  processed 10 insns

ii) BPF_ADD in 32 bit mode on r0 (map_value_adj):

  0: (bf) r2 = r10
  1: (07) r2 += -8
  2: (7a) *(u64 *)(r2 +0) = 0
  3: (18) r1 = 0xc24eee00
  5: (85) call bpf_map_lookup_elem#1
  6: (15) if r0 == 0x0 goto pc+2
   R0=map_value(ks=8,vs=48,id=0),min_value=0,max_value=0 R10=fp
  7: (04) (u32) r0 += (u32) 0
  8: (7a) *(u64 *)(r0 +0) = 22
   R0=map_value_adj(ks=8,vs=48,id=0),min_value=0,max_value=0 R10=fp
  9: (95) exit

  from 6 to 9: R0=inv,min_value=0,max_value=0 R10=fp
  9: (95) exit
  processed 10 insns

Issue is, while min_value / max_value boundaries for the access
are adjusted appropriately, we change the pointer value in a way
that cannot be sufficiently tracked anymore from its origin.
Operations like BPF_{AND,OR,DIV,MUL,etc} on a destination register
that is PTR_TO_MAP_VALUE{,_ADJ} was probably unintended, in fact,
all the test cases coming with 48461135 ("bpf: allow access
into map value arrays") perform BPF_ADD only on the destination
register that is PTR_TO_MAP_VALUE_ADJ.

Only for UNKNOWN_VALUE register types such operations make sense,
f.e. with unknown memory content fetched initially from a constant
offset from the map value memory into a register. That register is
then later tested against lower / upper bounds, so that the verifier
can then do the tracking of min_value / max_value, and properly
check once that UNKNOWN_VALUE register is added to the destination
register with type PTR_TO_MAP_VALUE{,_ADJ}. This is also what the
original use-case is solving. Note, tracking on what is being
added is done through adjust_reg_min_max_vals() and later access
to the map value enforced with these boundaries and the given offset
from the insn through check_map_access_adj().

Tests will fail for non-root environment due to prohibited pointer
arithmetic, in particular in check_alu_op(), we bail out on the
is_pointer_value() check on the dst_reg (which is false in root
case as we allow for pointer arithmetic via env->allow_ptr_leaks).

Similarly to PTR_TO_PACKET, one way to fix it is to restrict the
allowed operations on PTR_TO_MAP_VALUE{,_ADJ} registers to 64 bit
mode BPF_ADD. The test_verifier suite runs fine after the patch
and it also rejects mentioned test cases.

Fixes: 48461135 ("bpf: allow access into map value arrays")
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      fce366a9
    • R
      r8152: The Microsoft Surface docks also use R8152 v2 · d5b07ccc
      由 René Rebe 提交于 
      Without this the generic cdc_ether grabs the device,
and does not really work.
Signed-off-by: NRené Rebe <rene@exactcode.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      d5b07ccc
    • Y
      openvswitch: Fix ovs_flow_key_update() · 6f56f618
      由 Yi-Hung Wei 提交于 
      ovs_flow_key_update() is called when the flow key is invalid, and it is
used to update and revalidate the flow key. Commit 329f45bc
("openvswitch: add mac_proto field to the flow key") introduces mac_proto
field to flow key and use it to determine whether the flow key is valid.
However, the commit does not update the code path in ovs_flow_key_update()
to revalidate the flow key which may cause BUG_ON() on execute_recirc().
This patch addresses the aforementioned issue.

Fixes: 329f45bc ("openvswitch: add mac_proto field to the flow key")
Signed-off-by: NYi-Hung Wei <yihung.wei@gmail.com>
Acked-by: NJiri Benc <jbenc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      6f56f618
    • M
      net/faraday: Explicitly include linux/of.h and linux/property.h · 3af887c3
      由 Mark Brown 提交于 
      This driver uses interfaces from linux/of.h and linux/property.h but
relies on implict inclusion of those headers which means that changes in
other headers could break the build, as happened in -next for arm today.
Add a explicit includes.
Signed-off-by: NMark Brown <broonie@kernel.org>
Acked-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      3af887c3
    • D
      net: hns: Add ACPI support to check SFP present · b917078c
      由 Daode Huang 提交于 
      The current code only supports DT to check SFP present.
This patch adds ACPI support as well.
Signed-off-by: NDaode Huang <huangdaode@hisilicon.com>
Reviewed-by: NYisen Zhuang <yisen.zhuang@huawei.com>
Signed-off-by: NSalil Mehta <salil.mehta@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      b917078c
  11. 31 3月, 2017 8 次提交
  13. 30 3月, 2017 3 次提交
    • D
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf · 8f1f7eeb
      由 David S. Miller 提交于 
      Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains a rather large update with Netfilter
fixes, specifically targeted to incorrect RCU usage in several spots and
the userspace conntrack helper infrastructure (nfnetlink_cthelper),
more specifically they are:

1) expect_class_max is incorrect set via cthelper, as in kernel semantics
   mandate that this represents the array of expectation classes minus 1.
   Patch from Liping Zhang.

2) Expectation policy updates via cthelper are currently broken for several
   reasons: This code allows illegal changes in the policy such as changing
   the number of expeciation classes, it is leaking the updated policy and
   such update occurs with no RCU protection at all. Fix this by adding a
   new nfnl_cthelper_update_policy() that describes what is really legal on
   the update path.

3) Fix several memory leaks in cthelper, from Jeffy Chen.

4) synchronize_rcu() is missing in the removal path of several modules,
   this may lead to races since CPU may still be running on code that has
   just gone. Also from Liping Zhang.

5) Don't use the helper hashtable from cthelper, it is not safe to walk
   over those bits without the helper mutex. Fix this by introducing a
   new independent list for userspace helpers. From Liping Zhang.

6) nf_ct_extend_unregister() needs synchronize_rcu() to make sure no
   packets are walking on any conntrack extension that is gone after
   module removal, again from Liping.

7) nf_nat_snmp may crash if we fail to unregister the helper due to
   accidental leftover code, from Gao Feng.

8) Fix leak in nfnetlink_queue with secctx support, from Liping Zhang.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      8f1f7eeb
    • Z
      ezchip: nps_enet: check if napi has been completed · 358e78b5
      由 Zakharov Vlad 提交于 
      After a new NAPI_STATE_MISSED state was added to NAPI we can get into
this state and in such case we have to reschedule NAPI as some work is
still pending and we have to process it. napi_complete_done() function
returns false if we have to reschedule something (e.g. in case we were
in MISSED state) as current polling have not been completed yet.

nps_enet driver hasn't been verifying the return value of
napi_complete_done() and has been forcibly enabling interrupts. That is
not correct as we should not enable interrupts before we have processed
all scheduled work. As a result we were getting trapped in interrupt
hanlder chain as we had never been able to disabale ethernet
interrupts again.

So this patch makes nps_enet_poll() func verify return value of
napi_complete_done() and enable interrupts only in case all scheduled
work has been completed.
Signed-off-by: NVlad Zakharov <vzakhar@synopsys.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      358e78b5
    • D
      Merge branch 'bnxt_en-fixes' · a1801cc8
      由 David S. Miller 提交于 
      Michael Chan says:

====================
bnxt_en: Small misc. fixes.

Fix a NULL pointer crash in open failure path, wrong arguments when
printing error messages, and a DMA unmap bug in XDP shutdown path.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      a1801cc8