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  1. 04 Oct, 2019 1 commit
  3. 03 Oct, 2019 6 commits
    • Eric Dumazet's avatar
      tcp: fix slab-out-of-bounds in tcp_zerocopy_receive() · 3afb0961
      Eric Dumazet authored 
      Apparently a refactoring patch brought a bug, that was caught
by syzbot [1]

Original code was correct, do not try to be smarter than the
compiler :/

[1]
BUG: KASAN: slab-out-of-bounds in tcp_zerocopy_receive net/ipv4/tcp.c:1807 [inline]
BUG: KASAN: slab-out-of-bounds in do_tcp_getsockopt.isra.0+0x2c6c/0x3120 net/ipv4/tcp.c:3654
Read of size 4 at addr ffff8880943cf188 by task syz-executor.2/17508

CPU: 0 PID: 17508 Comm: syz-executor.2 Not tainted 5.3.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0xd4/0x306 mm/kasan/report.c:351
 __kasan_report.cold+0x1b/0x36 mm/kasan/report.c:482
 kasan_report+0x12/0x17 mm/kasan/common.c:618
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131
 tcp_zerocopy_receive net/ipv4/tcp.c:1807 [inline]
 do_tcp_getsockopt.isra.0+0x2c6c/0x3120 net/ipv4/tcp.c:3654
 tcp_getsockopt+0xbf/0xe0 net/ipv4/tcp.c:3680
 sock_common_getsockopt+0x94/0xd0 net/core/sock.c:3098
 __sys_getsockopt+0x16d/0x310 net/socket.c:2129
 __do_sys_getsockopt net/socket.c:2144 [inline]
 __se_sys_getsockopt net/socket.c:2141 [inline]
 __x64_sys_getsockopt+0xbe/0x150 net/socket.c:2141
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296

Fixes: d8e18a51 ("net: Use skb accessors in network core")
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarSoheil Hassas Yeganeh <soheil@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      3afb0961
    • Randy Dunlap's avatar
      lib: textsearch: fix escapes in example code · 2105b52e
      Randy Dunlap authored 
      This textsearch code example does not need the '\' escapes and they can
be misleading to someone reading the example. Also, gcc and sparse warn
that the "\%d" is an unknown escape sequence.

Fixes: 5968a70d ("textsearch: fix kernel-doc warnings and add kernel-api section")
Signed-off-by: default avatarRandy Dunlap <rdunlap@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      2105b52e
    • Josh Hunt's avatar
      udp: only do GSO if # of segs > 1 · 4094871d
      Josh Hunt authored 
      Prior to this change an application sending <= 1MSS worth of data and
enabling UDP GSO would fail if the system had SW GSO enabled, but the
same send would succeed if HW GSO offload is enabled. In addition to this
inconsistency the error in the SW GSO case does not get back to the
application if sending out of a real device so the user is unaware of this
failure.

With this change we only perform GSO if the # of segments is > 1 even
if the application has enabled segmentation. I've also updated the
relevant udpgso selftests.

Fixes: bec1f6f6 ("udp: generate gso with UDP_SEGMENT")
Signed-off-by: default avatarJosh Hunt <johunt@akamai.com>
Reviewed-by: default avatarWillem de Bruijn <willemb@google.com>
Reviewed-by: default avatarAlexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4094871d
    • Josh Hunt's avatar
      udp: fix gso_segs calculations · 44b321e5
      Josh Hunt authored 
      Commit dfec0ee2 ("udp: Record gso_segs when supporting UDP segmentation offload")
added gso_segs calculation, but incorrectly got sizeof() the pointer and
not the underlying data type. In addition let's fix the v6 case.

Fixes: bec1f6f6 ("udp: generate gso with UDP_SEGMENT")
Fixes: dfec0ee2 ("udp: Record gso_segs when supporting UDP segmentation offload")
Signed-off-by: default avatarJosh Hunt <johunt@akamai.com>
Reviewed-by: default avatarAlexander Duyck <alexander.h.duyck@linux.intel.com>
Acked-by: default avatarWillem de Bruijn <willemb@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      44b321e5
    • Eric Dumazet's avatar
      ipv6: drop incoming packets having a v4mapped source address · 6af1799a
      Eric Dumazet authored 
      This began with a syzbot report. syzkaller was injecting
IPv6 TCP SYN packets having a v4mapped source address.

After an unsuccessful 4-tuple lookup, TCP creates a request
socket (SYN_RECV) and calls reqsk_queue_hash_req()

reqsk_queue_hash_req() calls sk_ehashfn(sk)

At this point we have AF_INET6 sockets, and the heuristic
used by sk_ehashfn() to either hash the IPv4 or IPv6 addresses
is to use ipv6_addr_v4mapped(&sk->sk_v6_daddr)

For the particular spoofed packet, we end up hashing V4 addresses
which were not initialized by the TCP IPv6 stack, so KMSAN fired
a warning.

I first fixed sk_ehashfn() to test both source and destination addresses,
but then faced various problems, including user-space programs
like packetdrill that had similar assumptions.

Instead of trying to fix the whole ecosystem, it is better
to admit that we have a dual stack behavior, and that we
can not build linux kernels without V4 stack anyway.

The dual stack API automatically forces the traffic to be IPv4
if v4mapped addresses are used at bind() or connect(), so it makes
no sense to allow IPv6 traffic to use the same v4mapped class.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Reported-by: default avatarsyzbot <syzkaller@googlegroups.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      6af1799a
    • Thierry Reding's avatar
      net: stmmac: Avoid deadlock on suspend/resume · 134cc4ce
      Thierry Reding authored 
      The stmmac driver will try to acquire its private mutex during suspend
via phylink_resolve() -> stmmac_mac_link_down() -> stmmac_eee_init().
However, the phylink configuration is updated with the private mutex
held already, which causes a deadlock during suspend.

Fix this by moving the phylink configuration updates out of the region
of code protected by the private mutex.

Fixes: 19e13cb2 ("net: stmmac: Hold rtnl lock in suspend/resume callbacks")
Suggested-by: default avatarBitan Biswas <bbiswas@nvidia.com>
Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      134cc4ce
  5. 02 Oct, 2019 15 commits
    • Yizhuo's avatar
      net: hisilicon: Fix usage of uninitialized variable in function mdio_sc_cfg_reg_write() · 53de429f
      Yizhuo authored 
      In function mdio_sc_cfg_reg_write(), variable "reg_value" could be
uninitialized if regmap_read() fails. However, "reg_value" is used
to decide the control flow later in the if statement, which is
potentially unsafe.
Signed-off-by: default avatarYizhuo <yzhai003@ucr.edu>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      53de429f
    • David S. Miller's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf · 4fbb97ba
      David S. Miller authored 
      Pablo Neira Ayuso says:

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

The following patchset contains Netfilter fixes for net:

1) Remove the skb_ext_del from nf_reset, and renames it to a more
   fitting nf_reset_ct(). Patch from Florian Westphal.

2) Fix deadlock in nft_connlimit between packet path updates and
   the garbage collector.
====================
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4fbb97ba
    • Vladimir Oltean's avatar
      ptp_qoriq: Initialize the registers' spinlock before calling ptp_qoriq_settime · db34a471
      Vladimir Oltean authored 
      Because ptp_qoriq_settime is being called prior to spin_lock_init, the
following stack trace can be seen at driver probe time:

[    2.269117] the code is fine but needs lockdep annotation.
[    2.274569] turning off the locking correctness validator.
[    2.280027] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.3.0-rc7-01478-g01eaa67a4797 #263
[    2.288073] Hardware name: Freescale LS1021A
[    2.292337] [<c0313cb4>] (unwind_backtrace) from [<c030e11c>] (show_stack+0x10/0x14)
[    2.300045] [<c030e11c>] (show_stack) from [<c1219440>] (dump_stack+0xcc/0xf8)
[    2.307235] [<c1219440>] (dump_stack) from [<c03b9b44>] (register_lock_class+0x730/0x73c)
[    2.315372] [<c03b9b44>] (register_lock_class) from [<c03b6190>] (__lock_acquire+0x78/0x270c)
[    2.323856] [<c03b6190>] (__lock_acquire) from [<c03b90cc>] (lock_acquire+0xe0/0x22c)
[    2.331649] [<c03b90cc>] (lock_acquire) from [<c123c310>] (_raw_spin_lock_irqsave+0x54/0x68)
[    2.340048] [<c123c310>] (_raw_spin_lock_irqsave) from [<c0e73fe4>] (ptp_qoriq_settime+0x38/0x80)
[    2.348878] [<c0e73fe4>] (ptp_qoriq_settime) from [<c0e746d4>] (ptp_qoriq_init+0x1f8/0x484)
[    2.357189] [<c0e746d4>] (ptp_qoriq_init) from [<c0e74aac>] (ptp_qoriq_probe+0xd0/0x184)
[    2.365243] [<c0e74aac>] (ptp_qoriq_probe) from [<c0b0a07c>] (platform_drv_probe+0x48/0x9c)
[    2.373555] [<c0b0a07c>] (platform_drv_probe) from [<c0b07a14>] (really_probe+0x1c4/0x400)
[    2.381779] [<c0b07a14>] (really_probe) from [<c0b07e28>] (driver_probe_device+0x78/0x1b8)
[    2.390003] [<c0b07e28>] (driver_probe_device) from [<c0b081d0>] (device_driver_attach+0x58/0x60)
[    2.398832] [<c0b081d0>] (device_driver_attach) from [<c0b082d4>] (__driver_attach+0xfc/0x160)
[    2.407402] [<c0b082d4>] (__driver_attach) from [<c0b05a84>] (bus_for_each_dev+0x68/0xb4)
[    2.415539] [<c0b05a84>] (bus_for_each_dev) from [<c0b06b68>] (bus_add_driver+0x104/0x20c)
[    2.423763] [<c0b06b68>] (bus_add_driver) from [<c0b0909c>] (driver_register+0x78/0x10c)
[    2.431815] [<c0b0909c>] (driver_register) from [<c030313c>] (do_one_initcall+0x8c/0x3ac)
[    2.439954] [<c030313c>] (do_one_initcall) from [<c1f013f4>] (kernel_init_freeable+0x468/0x548)
[    2.448610] [<c1f013f4>] (kernel_init_freeable) from [<c12344d8>] (kernel_init+0x8/0x10c)
[    2.456745] [<c12344d8>] (kernel_init) from [<c03010b4>] (ret_from_fork+0x14/0x20)
[    2.464273] Exception stack(0xea89ffb0 to 0xea89fff8)
[    2.469297] ffa0:                                     00000000 00000000 00000000 00000000
[    2.477432] ffc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    2.485566] ffe0: 00000000 00000000 00000000 00000000 00000013 00000000

Fixes: ff54571a ("ptp_qoriq: convert to use ptp_qoriq_init/free")
Signed-off-by: default avatarVladimir Oltean <olteanv@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      db34a471
    • David S. Miller's avatar
      Merge branch 'SJA1105-DSA-locking-fixes-for-PTP' · 76d67494
      David S. Miller authored 
      Vladimir Oltean says:

====================
SJA1105 DSA locking fixes for PTP

This series fixes the locking API usage problems spotted when compiling
the kernel with CONFIG_DEBUG_ATOMIC_SLEEP=y and CONFIG_DEBUG_SPINLOCK=y.
====================
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      76d67494
    • Vladimir Oltean's avatar
      net: dsa: sja1105: Fix sleeping while atomic in .port_hwtstamp_set · 3e8db7e5
      Vladimir Oltean authored 
      Currently this stack trace can be seen with CONFIG_DEBUG_ATOMIC_SLEEP=y:

[   41.568348] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:909
[   41.576757] in_atomic(): 1, irqs_disabled(): 0, pid: 208, name: ptp4l
[   41.583212] INFO: lockdep is turned off.
[   41.587123] CPU: 1 PID: 208 Comm: ptp4l Not tainted 5.3.0-rc6-01445-ge950f2d4bc7f-dirty #1827
[   41.599873] [<c0313d7c>] (unwind_backtrace) from [<c030e13c>] (show_stack+0x10/0x14)
[   41.607584] [<c030e13c>] (show_stack) from [<c1212d50>] (dump_stack+0xd4/0x100)
[   41.614863] [<c1212d50>] (dump_stack) from [<c037dfc8>] (___might_sleep+0x1c8/0x2b4)
[   41.622574] [<c037dfc8>] (___might_sleep) from [<c122ea90>] (__mutex_lock+0x48/0xab8)
[   41.630368] [<c122ea90>] (__mutex_lock) from [<c122f51c>] (mutex_lock_nested+0x1c/0x24)
[   41.638340] [<c122f51c>] (mutex_lock_nested) from [<c0c6fe08>] (sja1105_static_config_reload+0x30/0x27c)
[   41.647779] [<c0c6fe08>] (sja1105_static_config_reload) from [<c0c7015c>] (sja1105_hwtstamp_set+0x108/0x1cc)
[   41.657562] [<c0c7015c>] (sja1105_hwtstamp_set) from [<c0feb650>] (dev_ifsioc+0x18c/0x330)
[   41.665788] [<c0feb650>] (dev_ifsioc) from [<c0febbd8>] (dev_ioctl+0x320/0x6e8)
[   41.673064] [<c0febbd8>] (dev_ioctl) from [<c0f8b1f4>] (sock_ioctl+0x334/0x5e8)
[   41.680340] [<c0f8b1f4>] (sock_ioctl) from [<c05404a8>] (do_vfs_ioctl+0xb0/0xa10)
[   41.687789] [<c05404a8>] (do_vfs_ioctl) from [<c0540e3c>] (ksys_ioctl+0x34/0x58)
[   41.695151] [<c0540e3c>] (ksys_ioctl) from [<c0301000>] (ret_fast_syscall+0x0/0x28)
[   41.702768] Exception stack(0xe8495fa8 to 0xe8495ff0)
[   41.707796] 5fa0:                   beff4a8c 00000001 00000011 000089b0 beff4a8c beff4a80
[   41.715933] 5fc0: beff4a8c 00000001 0000000c 00000036 b6fa98c8 004e19c1 00000001 00000000
[   41.724069] 5fe0: 004dcedc beff4a6c 004c0738 b6e7af4c
[   41.729860] BUG: scheduling while atomic: ptp4l/208/0x00000002
[   41.735682] INFO: lockdep is turned off.

Enabling RX timestamping will logically disturb the fastpath (processing
of meta frames). Replace bool hwts_rx_en with a bit that is checked
atomically from the fastpath and temporarily unset from the sleepable
context during a change of the RX timestamping process (a destructive
operation anyways, requires switch reset).
If found unset, the fastpath (net/dsa/tag_sja1105.c) will just drop any
received meta frame and not take the meta_lock at all.

Fixes: a602afd2 ("net: dsa: sja1105: Expose PTP timestamping ioctls to userspace")
Signed-off-by: default avatarVladimir Oltean <olteanv@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      3e8db7e5
    • Vladimir Oltean's avatar
      net: dsa: sja1105: Initialize the meta_lock · d6530e5a
      Vladimir Oltean authored 
      Otherwise, with CONFIG_DEBUG_SPINLOCK=y, this stack trace gets printed
when enabling RX timestamping and receiving a PTP frame:

[  318.537078] INFO: trying to register non-static key.
[  318.542040] the code is fine but needs lockdep annotation.
[  318.547500] turning off the locking correctness validator.
[  318.552972] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.3.0-13257-g0825b0669811-dirty #1962
[  318.561283] Hardware name: Freescale LS1021A
[  318.565566] [<c03144bc>] (unwind_backtrace) from [<c030e164>] (show_stack+0x10/0x14)
[  318.573289] [<c030e164>] (show_stack) from [<c11b9f50>] (dump_stack+0xd4/0x100)
[  318.580579] [<c11b9f50>] (dump_stack) from [<c03b9b40>] (register_lock_class+0x728/0x734)
[  318.588731] [<c03b9b40>] (register_lock_class) from [<c03b60c4>] (__lock_acquire+0x78/0x25cc)
[  318.597227] [<c03b60c4>] (__lock_acquire) from [<c03b8ef8>] (lock_acquire+0xd8/0x234)
[  318.605033] [<c03b8ef8>] (lock_acquire) from [<c11db934>] (_raw_spin_lock+0x44/0x54)
[  318.612755] [<c11db934>] (_raw_spin_lock) from [<c1164370>] (sja1105_rcv+0x1f8/0x4e8)
[  318.620561] [<c1164370>] (sja1105_rcv) from [<c115d7cc>] (dsa_switch_rcv+0x80/0x204)
[  318.628283] [<c115d7cc>] (dsa_switch_rcv) from [<c0f58c80>] (__netif_receive_skb_one_core+0x50/0x6c)
[  318.637386] [<c0f58c80>] (__netif_receive_skb_one_core) from [<c0f58f04>] (netif_receive_skb_internal+0xac/0x264)
[  318.647611] [<c0f58f04>] (netif_receive_skb_internal) from [<c0f59e98>] (napi_gro_receive+0x1d8/0x338)
[  318.656887] [<c0f59e98>] (napi_gro_receive) from [<c0c298a4>] (gfar_clean_rx_ring+0x328/0x724)
[  318.665472] [<c0c298a4>] (gfar_clean_rx_ring) from [<c0c29e60>] (gfar_poll_rx_sq+0x34/0x94)
[  318.673795] [<c0c29e60>] (gfar_poll_rx_sq) from [<c0f5b40c>] (net_rx_action+0x128/0x4f8)
[  318.681860] [<c0f5b40c>] (net_rx_action) from [<c03022f0>] (__do_softirq+0x148/0x5ac)
[  318.689666] [<c03022f0>] (__do_softirq) from [<c0355af4>] (irq_exit+0x160/0x170)
[  318.697040] [<c0355af4>] (irq_exit) from [<c03c6818>] (__handle_domain_irq+0x60/0xb4)
[  318.704847] [<c03c6818>] (__handle_domain_irq) from [<c07e9440>] (gic_handle_irq+0x58/0x9c)
[  318.713172] [<c07e9440>] (gic_handle_irq) from [<c0301a70>] (__irq_svc+0x70/0x98)
[  318.720622] Exception stack(0xc2001f18 to 0xc2001f60)
[  318.725656] 1f00:                                                       00000001 00000006
[  318.733805] 1f20: 00000000 c20165c0 ffffe000 c2010cac c2010cf4 00000001 00000000 c2010c88
[  318.741955] 1f40: c1f7a5a8 00000000 00000000 c2001f68 c03ba140 c030a288 200e0013 ffffffff
[  318.750110] [<c0301a70>] (__irq_svc) from [<c030a288>] (arch_cpu_idle+0x24/0x3c)
[  318.757486] [<c030a288>] (arch_cpu_idle) from [<c038a480>] (do_idle+0x1b8/0x2a4)
[  318.764859] [<c038a480>] (do_idle) from [<c038a94c>] (cpu_startup_entry+0x18/0x1c)
[  318.772407] [<c038a94c>] (cpu_startup_entry) from [<c1e00f10>] (start_kernel+0x4cc/0x4fc)

Fixes: 844d7edc ("net: dsa: sja1105: Add a global sja1105_tagger_data structure")
Signed-off-by: default avatarVladimir Oltean <olteanv@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      d6530e5a
    • Dotan Barak's avatar
      net/rds: Fix error handling in rds_ib_add_one() · d64bf89a
      Dotan Barak authored 
      rds_ibdev:ipaddr_list and rds_ibdev:conn_list are initialized
after allocation some resources such as protection domain.
If allocation of such resources fail, then these uninitialized
variables are accessed in rds_ib_dev_free() in failure path. This
can potentially crash the system. The code has been updated to
initialize these variables very early in the function.
Signed-off-by: default avatarDotan Barak <dotanb@dev.mellanox.co.il>
Signed-off-by: default avatarSudhakar Dindukurti <sudhakar.dindukurti@oracle.com>
Acked-by: default avatarSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      d64bf89a
    • Linus Walleij's avatar
      net: dsa: rtl8366: Check VLAN ID and not ports · e8521e53
      Linus Walleij authored 
      There has been some confusion between the port number and
the VLAN ID in this driver. What we need to check for
validity is the VLAN ID, nothing else.

The current confusion came from assigning a few default
VLANs for default routing and we need to rewrite that
properly.

Instead of checking if the port number is a valid VLAN
ID, check the actual VLAN IDs passed in to the callback
one by one as expected.

Fixes: d8652956 ("net: dsa: realtek-smi: Add Realtek SMI driver")
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e8521e53
    • Michal Kubecek's avatar
      mlx5: avoid 64-bit division in dr_icm_pool_mr_create() · 8b6b82ad
      Michal Kubecek authored 
      Recently added code introduces 64-bit division in dr_icm_pool_mr_create()
so that build on 32-bit architectures fails with

  ERROR: "__umoddi3" [drivers/net/ethernet/mellanox/mlx5/core/mlx5_core.ko] undefined!

As the divisor is always a power of 2, we can use bitwise operation
instead.

Fixes: 29cf8feb ("net/mlx5: DR, ICM pool memory allocator")
Reported-by: default avatarBorislav Petkov <bp@alien8.de>
Signed-off-by: default avatarMichal Kubecek <mkubecek@suse.cz>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      8b6b82ad
    • Tuong Lien's avatar
      tipc: fix unlimited bundling of small messages · e95584a8
      Tuong Lien authored 
      We have identified a problem with the "oversubscription" policy in the
link transmission code.

When small messages are transmitted, and the sending link has reached
the transmit window limit, those messages will be bundled and put into
the link backlog queue. However, bundles of data messages are counted
at the 'CRITICAL' level, so that the counter for that level, instead of
the counter for the real, bundled message's level is the one being
increased.
Subsequent, to-be-bundled data messages at non-CRITICAL levels continue
to be tested against the unchanged counter for their own level, while
contributing to an unrestrained increase at the CRITICAL backlog level.

This leaves a gap in congestion control algorithm for small messages
that can result in starvation for other users or a "real" CRITICAL
user. Even that eventually can lead to buffer exhaustion & link reset.

We fix this by keeping a 'target_bskb' buffer pointer at each levels,
then when bundling, we only bundle messages at the same importance
level only. This way, we know exactly how many slots a certain level
have occupied in the queue, so can manage level congestion accurately.

By bundling messages at the same level, we even have more benefits. Let
consider this:
- One socket sends 64-byte messages at the 'CRITICAL' level;
- Another sends 4096-byte messages at the 'LOW' level;

When a 64-byte message comes and is bundled the first time, we put the
overhead of message bundle to it (+ 40-byte header, data copy, etc.)
for later use, but the next message can be a 4096-byte one that cannot
be bundled to the previous one. This means the last bundle carries only
one payload message which is totally inefficient, as for the receiver
also! Later on, another 64-byte message comes, now we make a new bundle
and the same story repeats...

With the new bundling algorithm, this will not happen, the 64-byte
messages will be bundled together even when the 4096-byte message(s)
comes in between. However, if the 4096-byte messages are sent at the
same level i.e. 'CRITICAL', the bundling algorithm will again cause the
same overhead.

Also, the same will happen even with only one socket sending small
messages at a rate close to the link transmit's one, so that, when one
message is bundled, it's transmitted shortly. Then, another message
comes, a new bundle is created and so on...

We will solve this issue radically by another patch.

Fixes: 365ad353 ("tipc: reduce risk of user starvation during link congestion")
Reported-by: default avatarHoang Le <hoang.h.le@dektech.com.au>
Acked-by: default avatarJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: default avatarTuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e95584a8
    • Dongli Zhang's avatar
      xen-netfront: do not use ~0U as error return value for xennet_fill_frags() · a761129e
      Dongli Zhang authored 
      xennet_fill_frags() uses ~0U as return value when the sk_buff is not able
to cache extra fragments. This is incorrect because the return type of
xennet_fill_frags() is RING_IDX and 0xffffffff is an expected value for
ring buffer index.

In the situation when the rsp_cons is approaching 0xffffffff, the return
value of xennet_fill_frags() may become 0xffffffff which xennet_poll() (the
caller) would regard as error. As a result, queue->rx.rsp_cons is set
incorrectly because it is updated only when there is error. If there is no
error, xennet_poll() would be responsible to update queue->rx.rsp_cons.
Finally, queue->rx.rsp_cons would point to the rx ring buffer entries whose
queue->rx_skbs[i] and queue->grant_rx_ref[i] are already cleared to NULL.
This leads to NULL pointer access in the next iteration to process rx ring
buffer entries.

The symptom is similar to the one fixed in
commit 00b36850 ("xen-netfront: do not assume sk_buff_head list is
empty in error handling").

This patch changes the return type of xennet_fill_frags() to indicate
whether it is successful or failed. The queue->rx.rsp_cons will be
always updated inside this function.

Fixes: ad4f15dc ("xen/netfront: don't bug in case of too many frags")
Signed-off-by: default avatarDongli Zhang <dongli.zhang@oracle.com>
Reviewed-by: default avatarJuergen Gross <jgross@suse.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      a761129e
    • David Ahern's avatar
      ipv6: Handle race in addrconf_dad_work · a3ce2a21
      David Ahern authored 
      Rajendra reported a kernel panic when a link was taken down:

[ 6870.263084] BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8
[ 6870.271856] IP: [<ffffffff8efc5764>] __ipv6_ifa_notify+0x154/0x290

<snip>

[ 6870.570501] Call Trace:
[ 6870.573238] [<ffffffff8efc58c6>] ? ipv6_ifa_notify+0x26/0x40
[ 6870.579665] [<ffffffff8efc98ec>] ? addrconf_dad_completed+0x4c/0x2c0
[ 6870.586869] [<ffffffff8efe70c6>] ? ipv6_dev_mc_inc+0x196/0x260
[ 6870.593491] [<ffffffff8efc9c6a>] ? addrconf_dad_work+0x10a/0x430
[ 6870.600305] [<ffffffff8f01ade4>] ? __switch_to_asm+0x34/0x70
[ 6870.606732] [<ffffffff8ea93a7a>] ? process_one_work+0x18a/0x430
[ 6870.613449] [<ffffffff8ea93d6d>] ? worker_thread+0x4d/0x490
[ 6870.619778] [<ffffffff8ea93d20>] ? process_one_work+0x430/0x430
[ 6870.626495] [<ffffffff8ea99dd9>] ? kthread+0xd9/0xf0
[ 6870.632145] [<ffffffff8f01ade4>] ? __switch_to_asm+0x34/0x70
[ 6870.638573] [<ffffffff8ea99d00>] ? kthread_park+0x60/0x60
[ 6870.644707] [<ffffffff8f01ae77>] ? ret_from_fork+0x57/0x70
[ 6870.650936] Code: 31 c0 31 d2 41 b9 20 00 08 02 b9 09 00 00 0

addrconf_dad_work is kicked to be scheduled when a device is brought
up. There is a race between addrcond_dad_work getting scheduled and
taking the rtnl lock and a process taking the link down (under rtnl).
The latter removes the host route from the inet6_addr as part of
addrconf_ifdown which is run for NETDEV_DOWN. The former attempts
to use the host route in ipv6_ifa_notify. If the down event removes
the host route due to the race to the rtnl, then the BUG listed above
occurs.

This scenario does not occur when the ipv6 address is not kept
(net.ipv6.conf.all.keep_addr_on_down = 0) as addrconf_ifdown sets the
state of the ifp to DEAD. Handle when the addresses are kept by checking
IF_READY which is reset by addrconf_ifdown.

The 'dead' flag for an inet6_addr is set only under rtnl, in
addrconf_ifdown and it means the device is getting removed (or IPv6 is
disabled). The interesting cases for changing the idev flag are
addrconf_notify (NETDEV_UP and NETDEV_CHANGE) and addrconf_ifdown
(reset the flag). The former does not have the idev lock - only rtnl;
the latter has both. Based on that the existing dead + IF_READY check
can be moved to right after the rtnl_lock in addrconf_dad_work.

Fixes: f1705ec1 ("net: ipv6: Make address flushing on ifdown optional")
Reported-by: default avatarRajendra Dendukuri <rajendra.dendukuri@broadcom.com>
Signed-off-by: default avatarDavid Ahern <dsahern@gmail.com>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      a3ce2a21
    • Eric Dumazet's avatar
      tcp: adjust rto_base in retransmits_timed_out() · 3256a2d6
      Eric Dumazet authored 
      The cited commit exposed an old retransmits_timed_out() bug
which assumed it could call tcp_model_timeout() with
TCP_RTO_MIN as rto_base for all states.

But flows in SYN_SENT or SYN_RECV state uses a different
RTO base (1 sec instead of 200 ms, unless BPF choses
another value)

This caused a reduction of SYN retransmits from 6 to 4 with
the default /proc/sys/net/ipv4/tcp_syn_retries value.

Fixes: a41e8a88 ("tcp: better handle TCP_USER_TIMEOUT in SYN_SENT state")
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Marek Majkowski <marek@cloudflare.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      3256a2d6
    • Dexuan Cui's avatar
      vsock: Fix a lockdep warning in __vsock_release() · 0d9138ff
      Dexuan Cui authored 
      Lockdep is unhappy if two locks from the same class are held.

Fix the below warning for hyperv and virtio sockets (vmci socket code
doesn't have the issue) by using lock_sock_nested() when __vsock_release()
is called recursively:

============================================
WARNING: possible recursive locking detected
5.3.0+ #1 Not tainted
--------------------------------------------
server/1795 is trying to acquire lock:
ffff8880c5158990 (sk_lock-AF_VSOCK){+.+.}, at: hvs_release+0x10/0x120 [hv_sock]

but task is already holding lock:
ffff8880c5158150 (sk_lock-AF_VSOCK){+.+.}, at: __vsock_release+0x2e/0xf0 [vsock]

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(sk_lock-AF_VSOCK);
  lock(sk_lock-AF_VSOCK);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by server/1795:
 #0: ffff8880c5d05ff8 (&sb->s_type->i_mutex_key#10){+.+.}, at: __sock_release+0x2d/0xa0
 #1: ffff8880c5158150 (sk_lock-AF_VSOCK){+.+.}, at: __vsock_release+0x2e/0xf0 [vsock]

stack backtrace:
CPU: 5 PID: 1795 Comm: server Not tainted 5.3.0+ #1
Call Trace:
 dump_stack+0x67/0x90
 __lock_acquire.cold.67+0xd2/0x20b
 lock_acquire+0xb5/0x1c0
 lock_sock_nested+0x6d/0x90
 hvs_release+0x10/0x120 [hv_sock]
 __vsock_release+0x24/0xf0 [vsock]
 __vsock_release+0xa0/0xf0 [vsock]
 vsock_release+0x12/0x30 [vsock]
 __sock_release+0x37/0xa0
 sock_close+0x14/0x20
 __fput+0xc1/0x250
 task_work_run+0x98/0xc0
 do_exit+0x344/0xc60
 do_group_exit+0x47/0xb0
 get_signal+0x15c/0xc50
 do_signal+0x30/0x720
 exit_to_usermode_loop+0x50/0xa0
 do_syscall_64+0x24e/0x270
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f4184e85f31
Tested-by: default avatarStefano Garzarella <sgarzare@redhat.com>
Signed-off-by: default avatarDexuan Cui <decui@microsoft.com>
Reviewed-by: default avatarStefano Garzarella <sgarzare@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      0d9138ff
    • Johan Hovold's avatar
      hso: fix NULL-deref on tty open · 8353da9f
      Johan Hovold authored 
      Fix NULL-pointer dereference on tty open due to a failure to handle a
missing interrupt-in endpoint when probing modem ports:

	BUG: kernel NULL pointer dereference, address: 0000000000000006
	...
	RIP: 0010:tiocmget_submit_urb+0x1c/0xe0 [hso]
	...
	Call Trace:
	hso_start_serial_device+0xdc/0x140 [hso]
	hso_serial_open+0x118/0x1b0 [hso]
	tty_open+0xf1/0x490

Fixes: 542f5482 ("tty: Modem functions for the HSO driver")
Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      8353da9f
  7. 01 Oct, 2019 18 commits
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