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  1. Jul 19, 2021
  3. Jul 17, 2021
  5. Jul 16, 2021
  7. Jul 15, 2021
    • David S. Miller's avatar
      Merge branch 'r8152-pm-fixxes' · 3ffd3dad
      David S. Miller authored 
      Takashi Iwai says:

====================
r8152: Fix a couple of PM problems

it seems that r8152 driver suffers from the deadlock at both runtime
and system PM.  Formerly, it was seen more often at hibernation
resume, but now it's triggered more frequently, as reported in SUSE
Bugzilla:
  https://bugzilla.suse.com/show_bug.cgi?id=1186194

While debugging the problem, I stumbled on a few obvious bugs and here
is the results with two patches for addressing the resume problem.

***

However, the story doesn't end here, unfortunately, and those patches
don't seem sufficing.  The rest major problem is that the driver calls
napi_disable() and napi_enable() in the PM suspend callbacks.  This
makes the system stalling at (runtime-)suspend.  If we drop
napi_disable() and napi_enable() calls in the PM suspend callbacks, it
starts working (that was the result in Bugzilla comment 13):
  https://bugzilla.suse.com/show_bug.cgi?id=1186194#c13



So, my patches aren't enough and we still need to investigate
further.  It'd be appreciated if anyone can give a fix or a hint for
more debugging.  The usage of napi_disable() at PM callbacks is unique
in this driver and looks rather suspicious to me; but I'm no expert in
this area so I might be wrong...
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      3ffd3dad
    • Takashi Iwai's avatar
      r8152: Fix a deadlock by doubly PM resume · 776ac63a
      Takashi Iwai authored 
      r8152 driver sets up the MAC address at reset-resume, while
rtl8152_set_mac_address() has the temporary autopm get/put.  This may
lead to a deadlock as the PM lock has been already taken for the
execution of the runtime PM callback.

This patch adds the workaround to avoid the superfluous autpm when
called from rtl8152_reset_resume().

Link: https://bugzilla.suse.com/show_bug.cgi?id=1186194


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      776ac63a
    • Takashi Iwai's avatar
      r8152: Fix potential PM refcount imbalance · 9c23aa51
      Takashi Iwai authored 
      rtl8152_close() takes the refcount via usb_autopm_get_interface() but
it doesn't release when RTL8152_UNPLUG test hits.  This may lead to
the imbalance of PM refcount.  This patch addresses it.

Link: https://bugzilla.suse.com/show_bug.cgi?id=1186194


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      9c23aa51
    • Linus Torvalds's avatar
      Merge tag 'net-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net · 8096acd7
      Linus Torvalds authored 
      Pull networking fixes from Jakub Kicinski.
 "Including fixes from bpf and netfilter.

  Current release - regressions:

   - sock: fix parameter order in sock_setsockopt()

  Current release - new code bugs:

   - netfilter: nft_last:
       - fix incorrect arithmetic when restoring last used
       - honor NFTA_LAST_SET on restoration

  Previous releases - regressions:

   - udp: properly flush normal packet at GRO time

   - sfc: ensure correct number of XDP queues; don't allow enabling the
     feature if there isn't sufficient resources to Tx from any CPU

   - dsa: sja1105: fix address learning getting disabled on the CPU port

   - mptcp: addresses a rmem accounting issue that could keep packets in
     subflow receive buffers longer than necessary, delaying MPTCP-level
     ACKs

   - ip_tunnel: fix mtu calculation for ETHER tunnel devices

   - do not reuse skbs allocated from skbuff_fclone_cache in the napi
     skb cache, we'd try to return them to the wrong slab cache

   - tcp: consistently disable header prediction for mptcp

  Previous releases - always broken:

   - bpf: fix subprog poke descriptor tracking use-after-free

   - ipv6:
       - allocate enough headroom in ip6_finish_output2() in case
         iptables TEE is used
       - tcp: drop silly ICMPv6 packet too big messages to avoid
         expensive and pointless lookups (which may serve as a DDOS
         vector)
       - make sure fwmark is copied in SYNACK packets
       - fix 'disable_policy' for forwarded packets (align with IPv4)

   - netfilter: conntrack:
       - do not renew entry stuck in tcp SYN_SENT state
       - do not mark RST in the reply direction coming after SYN packet
         for an out-of-sync entry

   - mptcp: cleanly handle error conditions with MP_JOIN and syncookies

   - mptcp: fix double free when rejecting a join due to port mismatch

   - validate lwtstate->data before returning from skb_tunnel_info()

   - tcp: call sk_wmem_schedule before sk_mem_charge in zerocopy path

   - mt76: mt7921: continue to probe driver when fw already downloaded

   - bonding: fix multiple issues with offloading IPsec to (thru?) bond

   - stmmac: ptp: fix issues around Qbv support and setting time back

   - bcmgenet: always clear wake-up based on energy detection

  Misc:

   - sctp: move 198 addresses from unusable to private scope

   - ptp: support virtual clocks and timestamping

   - openvswitch: optimize operation for key comparison"

* tag 'net-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (158 commits)
  net: dsa: properly check for the bridge_leave methods in dsa_switch_bridge_leave()
  sfc: add logs explaining XDP_TX/REDIRECT is not available
  sfc: ensure correct number of XDP queues
  sfc: fix lack of XDP TX queues - error XDP TX failed (-22)
  net: fddi: fix UAF in fza_probe
  net: dsa: sja1105: fix address learning getting disabled on the CPU port
  net: ocelot: fix switchdev objects synced for wrong netdev with LAG offload
  net: Use nlmsg_unicast() instead of netlink_unicast()
  octeontx2-pf: Fix uninitialized boolean variable pps
  ipv6: allocate enough headroom in ip6_finish_output2()
  net: hdlc: rename 'mod_init' & 'mod_exit' functions to be module-specific
  net: bridge: multicast: fix MRD advertisement router port marking race
  net: bridge: multicast: fix PIM hello router port marking race
  net: phy: marvell10g: fix differentiation of 88X3310 from 88X3340
  dsa: fix for_each_child.cocci warnings
  virtio_net: check virtqueue_add_sgs() return value
  mptcp: properly account bulk freed memory
  selftests: mptcp: fix case multiple subflows limited by server
  mptcp: avoid processing packet if a subflow reset
  mptcp: fix syncookie process if mptcp can not_accept new subflow
  ...
      8096acd7
    • Christian Brauner's avatar
      fs: add vfs_parse_fs_param_source() helper · d1d488d8
      Christian Brauner authored 
      Add a simple helper that filesystems can use in their parameter parser
to parse the "source" parameter. A few places open-coded this function
and that already caused a bug in the cgroup v1 parser that we fixed.
Let's make it harder to get this wrong by introducing a helper which
performs all necessary checks.

Link: https://syzkaller.appspot.com/bug?id=6312526aba5beae046fdae8f00399f87aab48b12


Cc: Christoph Hellwig <hch@lst.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      d1d488d8
    • Christian Brauner's avatar
      cgroup: verify that source is a string · 3b046272
      Christian Brauner authored 
      The following sequence can be used to trigger a UAF:

    int fscontext_fd = fsopen("cgroup");
    int fd_null = open("/dev/null, O_RDONLY);
    int fsconfig(fscontext_fd, FSCONFIG_SET_FD, "source", fd_null);
    close_range(3, ~0U, 0);

The cgroup v1 specific fs parser expects a string for the "source"
parameter.  However, it is perfectly legitimate to e.g.  specify a file
descriptor for the "source" parameter.  The fs parser doesn't know what
a filesystem allows there.  So it's a bug to assume that "source" is
always of type fs_value_is_string when it can reasonably also be
fs_value_is_file.

This assumption in the cgroup code causes a UAF because struct
fs_parameter uses a union for the actual value.  Access to that union is
guarded by the param->type member.  Since the cgroup paramter parser
didn't check param->type but unconditionally moved param->string into
fc->source a close on the fscontext_fd would trigger a UAF during
put_fs_context() which frees fc->source thereby freeing the file stashed
in param->file causing a UAF during a close of the fd_null.

Fix this by verifying that param->type is actually a string and report
an error if not.

In follow up patches I'll add a new generic helper that can be used here
and by other filesystems instead of this error-prone copy-pasta fix.
But fixing it in here first makes backporting a it to stable a lot
easier.

Fixes: 8d2451f4

 ("cgroup1: switch to option-by-option parsing")
Reported-by: default avatar <syzbot+283ce5a46486d6acdbaf@syzkaller.appspotmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@kernel.org>
Cc: syzkaller-bugs <syzkaller-bugs@googlegroups.com>
Signed-off-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      3b046272
  9. Jul 14, 2021
    • Vladimir Oltean's avatar
      net: dsa: properly check for the bridge_leave methods in dsa_switch_bridge_leave() · bcb9928a
      Vladimir Oltean authored 
      This was not caught because there is no switch driver which implements
the .port_bridge_join but not .port_bridge_leave method, but it should
nonetheless be fixed, as in certain conditions (driver development) it
might lead to NULL pointer dereference.

Fixes: f66a6a69

 ("net: dsa: permit cross-chip bridging between all trees in the system")
Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      bcb9928a
    • Linus Torvalds's avatar
      Merge tag 'vboxsf-v5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/hansg/linux · 40226a3d
      Linus Torvalds authored 
      Pull vboxsf fixes from Hans de Goede:
 "This adds support for the atomic_open directory-inode op to vboxsf.

  Note this is not just an enhancement this also fixes an actual issue
  which users are hitting, see the commit message of the "boxsf: Add
  support for the atomic_open directory-inode" patch"

* tag 'vboxsf-v5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/hansg/linux:
  vboxsf: Add support for the atomic_open directory-inode op
  vboxsf: Add vboxsf_[create|release]_sf_handle() helpers
  vboxsf: Make vboxsf_dir_create() return the handle for the created file
  vboxsf: Honor excl flag to the dir-inode create op
      40226a3d
    • Linus Torvalds's avatar
      Merge tag 'for-5.14-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux · f02bf857
      Linus Torvalds authored 
      Pull btrfs zoned mode fixes from David Sterba:

 - fix deadlock when allocating system chunk

 - fix wrong mutex unlock on an error path

 - fix extent map splitting for append operation

 - update and fix message reporting unusable chunk space

 - don't block when background zone reclaim runs with balance in
   parallel

* tag 'for-5.14-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: zoned: fix wrong mutex unlock on failure to allocate log root tree
  btrfs: don't block if we can't acquire the reclaim lock
  btrfs: properly split extent_map for REQ_OP_ZONE_APPEND
  btrfs: rework chunk allocation to avoid exhaustion of the system chunk array
  btrfs: fix deadlock with concurrent chunk allocations involving system chunks
  btrfs: zoned: print unusable percentage when reclaiming block groups
  btrfs: zoned: fix types for u64 division in btrfs_reclaim_bgs_work
      f02bf857
    • David S. Miller's avatar
      Merge branch 'sfc-tx-queues' · 28efd208
      David S. Miller authored 
      Íñigo Huguet says:

====================
sfc: Fix lack of XDP TX queues

A change introduced in commit e26ca4b5 ("sfc: reduce the number of
requested xdp ev queues") created a bug in XDP_TX and XDP_REDIRECT
because it unintentionally reduced the number of XDP TX queues, letting
not enough queues to have one per CPU, which leaded to errors if XDP
TX/REDIRECT was done from a high numbered CPU.

This patchs make the following changes:
- Fix the bug mentioned above
- Revert commit 99ba0ea6

 ("sfc: adjust efx->xdp_tx_queue_count with
  the real number of initialized queues") which intended to fix a related
  problem, created by mentioned bug, but it's no longer necessary
- Add a new error log message if there are not enough resources to make
  XDP_TX/REDIRECT work

V1 -> V2: keep the calculation of how many tx queues can handle a single
event queue, but apply the "max. tx queues per channel" upper limit.
V2 -> V3: WARN_ON if the number of initialized XDP TXQs differs from the
expected.
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      28efd208
    • Íñigo Huguet's avatar
      sfc: add logs explaining XDP_TX/REDIRECT is not available · d2a16bde
      Íñigo Huguet authored 
      

If it's not possible to allocate enough channels for XDP, XDP_TX and
XDP_REDIRECT don't work. However, only a message saying that not enough
channels were available was shown, but not saying what are the
consequences in that case. The user didn't know if he/she can use XDP
or not, if the performance is reduced, or what.

Signed-off-by: default avatarÍñigo Huguet <ihuguet@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      d2a16bde
    • Íñigo Huguet's avatar
      sfc: ensure correct number of XDP queues · 788bc000
      Íñigo Huguet authored 
      Commit 99ba0ea6 ("sfc: adjust efx->xdp_tx_queue_count with the real
number of initialized queues") intended to fix a problem caused by a
round up when calculating the number of XDP channels and queues.
However, this was not the real problem. The real problem was that the
number of XDP TX queues had been reduced to half in
commit e26ca4b5

 ("sfc: reduce the number of requested xdp ev queues"),
but the variable xdp_tx_queue_count had remained the same.

Once the correct number of XDP TX queues is created again in the
previous patch of this series, this also can be reverted since the error
doesn't actually exist.

Only in the case that there is a bug in the code we can have different
values in xdp_queue_number and efx->xdp_tx_queue_count. Because of this,
and per Edward Cree's suggestion, I add instead a WARN_ON to catch if it
happens again in the future.

Note that the number of allocated queues can be higher than the number
of used ones due to the round up, as explained in the existing comment
in the code. That's why we also have to stop increasing xdp_queue_number
beyond efx->xdp_tx_queue_count.

Signed-off-by: default avatarÍñigo Huguet <ihuguet@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      788bc000
    • Íñigo Huguet's avatar
      sfc: fix lack of XDP TX queues - error XDP TX failed (-22) · f28100cb
      Íñigo Huguet authored 
      Fixes: e26ca4b5 sfc: reduce the number of requested xdp ev queues

The buggy commit intended to allocate less channels for XDP in order to
be more unlikely to reach the limit of 32 channels of the driver.

The idea was to use each IRQ/eventqeue for more XDP TX queues than
before, calculating which is the maximum number of TX queues that one
event queue can handle. For example, in EF10 each event queue could
handle up to 8 queues, better than the 4 they were handling before the
change. This way, it would have to allocate half of channels than before
for XDP TX.

The problem is that the TX queues are also contained inside the channel
structs, and there are only 4 queues per channel. Reducing the number of
channels means also reducing the number of queues, resulting in not
having the desired number of 1 queue per CPU.

This leads to getting errors on XDP_TX and XDP_REDIRECT if they're
executed from a high numbered CPU, because there only exist queues for
the low half of CPUs, actually. If XDP_TX/REDIRECT is executed in a low
numbered CPU, the error doesn't happen. This is the error in the logs
(repeated many times, even rate limited):
sfc 0000:5e:00.0 ens3f0np0: XDP TX failed (-22)

This errors happens in function efx_xdp_tx_buffers, where it expects to
have a dedicated XDP TX queue per CPU.

Reverting the change makes again more likely to reach the limit of 32
channels in machines with many CPUs. If this happen, no XDP_TX/REDIRECT
will be possible at all, and we will have this log error messages:

At interface probe:
sfc 0000:5e:00.0: Insufficient resources for 12 XDP event queues (24 other channels, max 32)

At every subsequent XDP_TX/REDIRECT failure, rate limited:
sfc 0000:5e:00.0 ens3f0np0: XDP TX failed (-22)

However, without reverting the change, it makes the user to think that
everything is OK at probe time, but later it fails in an unpredictable
way, depending on the CPU that handles the packet.

It is better to restore the predictable behaviour. If the user sees the
error message at probe time, he/she can try to configure the best way it
fits his/her needs. At least, he/she will have 2 options:
- Accept that XDP_TX/REDIRECT is not available (he/she may not need it)
- Load sfc module with modparam 'rss_cpus' with a lower number, thus
  creating less normal RX queues/channels, letting more free resources
  for XDP, with some performance penalty.

Anyway, let the calculation of maximum TX queues that can be handled by
a single event queue, and use it only if it's less than the number of TX
queues per channel. This doesn't happen in practice, but could happen if
some constant values are tweaked in the future, such us
EFX_MAX_TXQ_PER_CHANNEL, EFX_MAX_EVQ_SIZE or EFX_MAX_DMAQ_SIZE.

Related mailing list thread:
https://lore.kernel.org/bpf/20201215104327.2be76156@carbon/



Signed-off-by: default avatarÍñigo Huguet <ihuguet@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      f28100cb
    • Pavel Skripkin's avatar
      net: fddi: fix UAF in fza_probe · deb7178e
      Pavel Skripkin authored 
      fp is netdev private data and it cannot be
used after free_netdev() call. Using fp after free_netdev()
can cause UAF bug. Fix it by moving free_netdev() after error message.

Fixes: 61414f5e

 ("FDDI: defza: Add support for DEC FDDIcontroller 700
TURBOchannel adapter")
Signed-off-by: default avatarPavel Skripkin <paskripkin@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      deb7178e
    • Vladimir Oltean's avatar
      net: dsa: sja1105: fix address learning getting disabled on the CPU port · b0b33b04
      Vladimir Oltean authored 
      In May 2019 when commit 640f763f ("net: dsa: sja1105: Add support
for Spanning Tree Protocol") was introduced, the comment that "STP does
not get called for the CPU port" was true. This changed after commit
0394a63a ("net: dsa: enable and disable all ports") in August 2019
and went largely unnoticed, because the sja1105_bridge_stp_state_set()
method did nothing different compared to the static setup done by
sja1105_init_mac_settings().

With the ability to turn address learning off introduced by the blamed
commit, there is a new priv->learn_ena port mask in the driver. When
sja1105_bridge_stp_state_set() gets called and we are in
BR_STATE_LEARNING or later, address learning is enabled or not depending
on priv->learn_ena & BIT(port).

So what happens is that priv->learn_ena is not being set from anywhere
for the CPU port, and the static configuration done by
sja1105_init_mac_settings() is being overwritten.

To solve this, acknowledge that the static configuration of STP state is
no longer necessary because the STP state is being set by the DSA core
now, but what is necessary is to set priv->learn_ena for the CPU port.

Fixes: 4d942354

 ("net: dsa: sja1105: offload bridge port flags to device")
Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b0b33b04
    • Vladimir Oltean's avatar
      net: ocelot: fix switchdev objects synced for wrong netdev with LAG offload · e56c6bbd
      Vladimir Oltean authored 
      The point with a *dev and a *brport_dev is that when we have a LAG net
device that is a bridge port, *dev is an ocelot net device and
*brport_dev is the bonding/team net device. The ocelot net device
beneath the LAG does not exist from the bridge's perspective, so we need
to sync the switchdev objects belonging to the brport_dev and not to the
dev.

Fixes: e4bd44e8

 ("net: ocelot: replay switchdev events when joining bridge")
Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e56c6bbd
    • Yajun Deng's avatar
      net: Use nlmsg_unicast() instead of netlink_unicast() · 01757f53
      Yajun Deng authored 
      

It has 'if (err >0 )' statement in nlmsg_unicast(), so use nlmsg_unicast()
instead of netlink_unicast(), this looks more concise.

v2: remove the change in netfilter.

Signed-off-by: default avatarYajun Deng <yajun.deng@linux.dev>
Reviewed-by: default avatarDavid Ahern <dsahern@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      01757f53
  11. Jul 13, 2021
    • Xuan Zhuo's avatar
      xdp, net: Fix use-after-free in bpf_xdp_link_release · 5acc7d3e
      Xuan Zhuo authored 
      The problem occurs between dev_get_by_index() and dev_xdp_attach_link().
At this point, dev_xdp_uninstall() is called. Then xdp link will not be
detached automatically when dev is released. But link->dev already
points to dev, when xdp link is released, dev will still be accessed,
but dev has been released.

dev_get_by_index()        |
link->dev = dev           |
                          |      rtnl_lock()
                          |      unregister_netdevice_many()
                          |          dev_xdp_uninstall()
                          |      rtnl_unlock()
rtnl_lock();              |
dev_xdp_attach_link()     |
rtnl_unlock();            |
                          |      netdev_run_todo() // dev released
bpf_xdp_link_release()    |
    /* access dev.        |
       use-after-free */  |

[   45.966867] BUG: KASAN: use-after-free in bpf_xdp_link_release+0x3b8/0x3d0
[   45.967619] Read of size 8 at addr ffff00000f9980c8 by task a.out/732
[   45.968297]
[   45.968502] CPU: 1 PID: 732 Comm: a.out Not tainted 5.13.0+ #22
[   45.969222] Hardware name: linux,dummy-virt (DT)
[   45.969795] Call trace:
[   45.970106]  dump_backtrace+0x0/0x4c8
[   45.970564]  show_stack+0x30/0x40
[   45.970981]  dump_stack_lvl+0x120/0x18c
[   45.971470]  print_address_description.constprop.0+0x74/0x30c
[   45.972182]  kasan_report+0x1e8/0x200
[   45.972659]  __asan_report_load8_noabort+0x2c/0x50
[   45.973273]  bpf_xdp_link_release+0x3b8/0x3d0
[   45.973834]  bpf_link_free+0xd0/0x188
[   45.974315]  bpf_link_put+0x1d0/0x218
[   45.974790]  bpf_link_release+0x3c/0x58
[   45.975291]  __fput+0x20c/0x7e8
[   45.975706]  ____fput+0x24/0x30
[   45.976117]  task_work_run+0x104/0x258
[   45.976609]  do_notify_resume+0x894/0xaf8
[   45.977121]  work_pending+0xc/0x328
[   45.977575]
[   45.977775] The buggy address belongs to the page:
[   45.978369] page:fffffc00003e6600 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4f998
[   45.979522] flags: 0x7fffe0000000000(node=0|zone=0|lastcpupid=0x3ffff)
[   45.980349] raw: 07fffe0000000000 fffffc00003e6708 ffff0000dac3c010 0000000000000000
[   45.981309] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
[   45.982259] page dumped because: kasan: bad access detected
[   45.982948]
[   45.983153] Memory state around the buggy address:
[   45.983753]  ffff00000f997f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   45.984645]  ffff00000f998000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[   45.985533] >ffff00000f998080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[   45.986419]                                               ^
[   45.987112]  ffff00000f998100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[   45.988006]  ffff00000f998180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[   45.988895] ==================================================================
[   45.989773] Disabling lock debugging due to kernel taint
[   45.990552] Kernel panic - not syncing: panic_on_warn set ...
[   45.991166] CPU: 1 PID: 732 Comm: a.out Tainted: G    B             5.13.0+ #22
[   45.991929] Hardware name: linux,dummy-virt (DT)
[   45.992448] Call trace:
[   45.992753]  dump_backtrace+0x0/0x4c8
[   45.993208]  show_stack+0x30/0x40
[   45.993627]  dump_stack_lvl+0x120/0x18c
[   45.994113]  dump_stack+0x1c/0x34
[   45.994530]  panic+0x3a4/0x7d8
[   45.994930]  end_report+0x194/0x198
[   45.995380]  kasan_report+0x134/0x200
[   45.995850]  __asan_report_load8_noabort+0x2c/0x50
[   45.996453]  bpf_xdp_link_release+0x3b8/0x3d0
[   45.997007]  bpf_link_free+0xd0/0x188
[   45.997474]  bpf_link_put+0x1d0/0x218
[   45.997942]  bpf_link_release+0x3c/0x58
[   45.998429]  __fput+0x20c/0x7e8
[   45.998833]  ____fput+0x24/0x30
[   45.999247]  task_work_run+0x104/0x258
[   45.999731]  do_notify_resume+0x894/0xaf8
[   46.000236]  work_pending+0xc/0x328
[   46.000697] SMP: stopping secondary CPUs
[   46.001226] Dumping ftrace buffer:
[   46.001663]    (ftrace buffer empty)
[   46.002110] Kernel Offset: disabled
[   46.002545] CPU features: 0x00000001,23202c00
[   46.003080] Memory Limit: none

Fixes: aa8d3a71

 ("bpf, xdp: Add bpf_link-based XDP attachment API")
Reported-by: default avatarAbaci <abaci@linux.alibaba.com>
Signed-off-by: default avatarXuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Reviewed-by: default avatarDust Li <dust.li@linux.alibaba.com>
Acked-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210710031635.41649-1-xuanzhuo@linux.alibaba.com
      5acc7d3e
    • Daniel Borkmann's avatar
      bpf: Fix tail_call_reachable rejection for interpreter when jit failed · 5dd0a6b8
      Daniel Borkmann authored 
      During testing of f263a814 ("bpf: Track subprog poke descriptors correctly
and fix use-after-free") under various failure conditions, for example, when
jit_subprogs() fails and tries to clean up the program to be run under the
interpreter, we ran into the following freeze:

  [...]
  #127/8 tailcall_bpf2bpf_3:FAIL
  [...]
  [   92.041251] BUG: KASAN: slab-out-of-bounds in ___bpf_prog_run+0x1b9d/0x2e20
  [   92.042408] Read of size 8 at addr ffff88800da67f68 by task test_progs/682
  [   92.043707]
  [   92.044030] CPU: 1 PID: 682 Comm: test_progs Tainted: G   O   5.13.0-53301-ge6c08cb33a30-dirty #87
  [   92.045542] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014
  [   92.046785] Call Trace:
  [   92.047171]  ? __bpf_prog_run_args64+0xc0/0xc0
  [   92.047773]  ? __bpf_prog_run_args32+0x8b/0xb0
  [   92.048389]  ? __bpf_prog_run_args64+0xc0/0xc0
  [   92.049019]  ? ktime_get+0x117/0x130
  [...] // few hundred [similar] lines more
  [   92.659025]  ? ktime_get+0x117/0x130
  [   92.659845]  ? __bpf_prog_run_args64+0xc0/0xc0
  [   92.660738]  ? __bpf_prog_run_args32+0x8b/0xb0
  [   92.661528]  ? __bpf_prog_run_args64+0xc0/0xc0
  [   92.662378]  ? print_usage_bug+0x50/0x50
  [   92.663221]  ? print_usage_bug+0x50/0x50
  [   92.664077]  ? bpf_ksym_find+0x9c/0xe0
  [   92.664887]  ? ktime_get+0x117/0x130
  [   92.665624]  ? kernel_text_address+0xf5/0x100
  [   92.666529]  ? __kernel_text_address+0xe/0x30
  [   92.667725]  ? unwind_get_return_address+0x2f/0x50
  [   92.668854]  ? ___bpf_prog_run+0x15d4/0x2e20
  [   92.670185]  ? ktime_get+0x117/0x130
  [   92.671130]  ? __bpf_prog_run_args64+0xc0/0xc0
  [   92.672020]  ? __bpf_prog_run_args32+0x8b/0xb0
  [   92.672860]  ? __bpf_prog_run_args64+0xc0/0xc0
  [   92.675159]  ? ktime_get+0x117/0x130
  [   92.677074]  ? lock_is_held_type+0xd5/0x130
  [   92.678662]  ? ___bpf_prog_run+0x15d4/0x2e20
  [   92.680046]  ? ktime_get+0x117/0x130
  [   92.681285]  ? __bpf_prog_run32+0x6b/0x90
  [   92.682601]  ? __bpf_prog_run64+0x90/0x90
  [   92.683636]  ? lock_downgrade+0x370/0x370
  [   92.684647]  ? mark_held_locks+0x44/0x90
  [   92.685652]  ? ktime_get+0x117/0x130
  [   92.686752]  ? lockdep_hardirqs_on+0x79/0x100
  [   92.688004]  ? ktime_get+0x117/0x130
  [   92.688573]  ? __cant_migrate+0x2b/0x80
  [   92.689192]  ? bpf_test_run+0x2f4/0x510
  [   92.689869]  ? bpf_test_timer_continue+0x1c0/0x1c0
  [   92.690856]  ? rcu_read_lock_bh_held+0x90/0x90
  [   92.691506]  ? __kasan_slab_alloc+0x61/0x80
  [   92.692128]  ? eth_type_trans+0x128/0x240
  [   92.692737]  ? __build_skb+0x46/0x50
  [   92.693252]  ? bpf_prog_test_run_skb+0x65e/0xc50
  [   92.693954]  ? bpf_prog_test_run_raw_tp+0x2d0/0x2d0
  [   92.694639]  ? __fget_light+0xa1/0x100
  [   92.695162]  ? bpf_prog_inc+0x23/0x30
  [   92.695685]  ? __sys_bpf+0xb40/0x2c80
  [   92.696324]  ? bpf_link_get_from_fd+0x90/0x90
  [   92.697150]  ? mark_held_locks+0x24/0x90
  [   92.698007]  ? lockdep_hardirqs_on_prepare+0x124/0x220
  [   92.699045]  ? finish_task_switch+0xe6/0x370
  [   92.700072]  ? lockdep_hardirqs_on+0x79/0x100
  [   92.701233]  ? finish_task_switch+0x11d/0x370
  [   92.702264]  ? __switch_to+0x2c0/0x740
  [   92.703148]  ? mark_held_locks+0x24/0x90
  [   92.704155]  ? __x64_sys_bpf+0x45/0x50
  [   92.705146]  ? do_syscall_64+0x35/0x80
  [   92.706953]  ? entry_SYSCALL_64_after_hwframe+0x44/0xae
  [...]

Turns out that the program rejection from e411901c ("bpf: allow for tailcalls
in BPF subprograms for x64 JIT") is buggy since env->prog->aux->tail_call_reachable
is never true. Commit ebf7d1f5 ("bpf, x64: rework pro/epilogue and tailcall
handling in JIT") added a tracker into check_max_stack_depth() which propagates
the tail_call_reachable condition throughout the subprograms. This info is then
assigned to the subprogram's func[i]->aux->tail_call_reachable. However, in the
case of the rejection check upon JIT failure, env->prog->aux->tail_call_reachable
is used. func[0]->aux->tail_call_reachable which represents the main program's
information did not propagate this to the outer env->prog->aux, though. Add this
propagation into check_max_stack_depth() where it needs to belong so that the
check can be done reliably.

Fixes: ebf7d1f5 ("bpf, x64: rework pro/epilogue and tailcall handling in JIT")
Fixes: e411901c

 ("bpf: allow for tailcalls in BPF subprograms for x64 JIT")
Co-developed-by: default avatarJohn Fastabend <john.fastabend@gmail.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarJohn Fastabend <john.fastabend@gmail.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Acked-by: default avatarMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/618c34e3163ad1a36b1e82377576a6081e182f25.1626123173.git.daniel@iogearbox.net
      5dd0a6b8
    • Christoph Hellwig's avatar
      sd: don't mess with SD_MINORS for CONFIG_DEBUG_BLOCK_EXT_DEVT · 7fef2edf
      Christoph Hellwig authored 
      No need to give up the original sd minor even with this option,
and if we did we'd also need to fix the number of minors for
this configuration to actually work.

Fixes: 7c3f828b

 ("block: refactor device number setup in __device_add_disk")
Reported-by: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Tested-by: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      7fef2edf
    • Matthew Wilcox (Oracle)'s avatar
      mm: Make copy_huge_page() always available · 79789db0
      Matthew Wilcox (Oracle) authored 
      Rewrite copy_huge_page() and move it into mm/util.c so it's always
available.  Fixes an exposure of uninitialised memory on configurations
with HUGETLB and UFFD enabled and MIGRATION disabled.

Fixes: 8cc5fcbb

 ("mm, hugetlb: fix racy resv_huge_pages underflow on UFFDIO_COPY")
Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      79789db0