Skip to content

L
linux
Switch branch/tag
  1. 20 Oct, 2018 5 commits
  3. 19 Oct, 2018 11 commits
  5. 18 Oct, 2018 24 commits
    • Stefano Brivio's avatar
      ip6_tunnel: Fix encapsulation layout · d4d576f5
      Stefano Brivio authored 
      Commit 058214a4 ("ip6_tun: Add infrastructure for doing
encapsulation") added the ip6_tnl_encap() call in ip6_tnl_xmit(), before
the call to ipv6_push_frag_opts() to append the IPv6 Tunnel Encapsulation
Limit option (option 4, RFC 2473, par. 5.1) to the outer IPv6 header.

As long as the option didn't actually end up in generated packets, this
wasn't an issue. Then commit 89a23c8b ("ip6_tunnel: Fix missing tunnel
encapsulation limit option") fixed sending of this option, and the
resulting layout, e.g. for FoU, is:

.-------------------.------------.----------.-------------------.----- - -
| Outer IPv6 Header | UDP header | Option 4 | Inner IPv6 Header | Payload
'-------------------'------------'----------'-------------------'----- - -

Needless to say, FoU and GUE (at least) won't work over IPv6. The option
is appended by default, and I couldn't find a way to disable it with the
current iproute2.

Turn this into a more reasonable:

.-------------------.----------.------------.-------------------.----- - -
| Outer IPv6 Header | Option 4 | UDP header | Inner IPv6 Header | Payload
'-------------------'----------'------------'-------------------'----- - -

With this, and with 84dad559 ("udp6: fix encap return code for
resubmitting"), FoU and GUE work again over IPv6.

Fixes: 058214a4 ("ip6_tun: Add infrastructure for doing encapsulation")
Signed-off-by: default avatarStefano Brivio <sbrivio@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      d4d576f5
    • Jon Maloy's avatar
      tipc: fix info leak from kernel tipc_event · b06f9d9f
      Jon Maloy authored 
      We initialize a struct tipc_event allocated on the kernel stack to
zero to avert info leak to user space.

Reported-by: syzbot+057458894bc8cada4dee@syzkaller.appspotmail.com
Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b06f9d9f
    • Wenwen Wang's avatar
      net: socket: fix a missing-check bug · b6168562
      Wenwen Wang authored 
      In ethtool_ioctl(), the ioctl command 'ethcmd' is checked through a switch
statement to see whether it is necessary to pre-process the ethtool
structure, because, as mentioned in the comment, the structure
ethtool_rxnfc is defined with padding. If yes, a user-space buffer 'rxnfc'
is allocated through compat_alloc_user_space(). One thing to note here is
that, if 'ethcmd' is ETHTOOL_GRXCLSRLALL, the size of the buffer 'rxnfc' is
partially determined by 'rule_cnt', which is actually acquired from the
user-space buffer 'compat_rxnfc', i.e., 'compat_rxnfc->rule_cnt', through
get_user(). After 'rxnfc' is allocated, the data in the original user-space
buffer 'compat_rxnfc' is then copied to 'rxnfc' through copy_in_user(),
including the 'rule_cnt' field. However, after this copy, no check is
re-enforced on 'rxnfc->rule_cnt'. So it is possible that a malicious user
race to change the value in the 'compat_rxnfc->rule_cnt' between these two
copies. Through this way, the attacker can bypass the previous check on
'rule_cnt' and inject malicious data. This can cause undefined behavior of
the kernel and introduce potential security risk.

This patch avoids the above issue via copying the value acquired by
get_user() to 'rxnfc->rule_cn', if 'ethcmd' is ETHTOOL_GRXCLSRLALL.
Signed-off-by: default avatarWenwen Wang <wang6495@umn.edu>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b6168562
    • Phil Sutter's avatar
      net: sched: Fix for duplicate class dump · 3c53ed8f
      Phil Sutter authored 
      When dumping classes by parent, kernel would return classes twice:

| # tc qdisc add dev lo root prio
| # tc class show dev lo
| class prio 8001:1 parent 8001:
| class prio 8001:2 parent 8001:
| class prio 8001:3 parent 8001:
| # tc class show dev lo parent 8001:
| class prio 8001:1 parent 8001:
| class prio 8001:2 parent 8001:
| class prio 8001:3 parent 8001:
| class prio 8001:1 parent 8001:
| class prio 8001:2 parent 8001:
| class prio 8001:3 parent 8001:

This comes from qdisc_match_from_root() potentially returning the root
qdisc itself if its handle matched. Though in that case, root's classes
were already dumped a few lines above.

Fixes: cb395b20 ("net: sched: optimize class dumps")
Signed-off-by: default avatarPhil Sutter <phil@nwl.cc>
Reviewed-by: default avatarJiri Pirko <jiri@mellanox.com>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      3c53ed8f
    • Heiner Kallweit's avatar
      r8169: fix NAPI handling under high load · 6b839b6c
      Heiner Kallweit authored 
      rtl_rx() and rtl_tx() are called only if the respective bits are set
in the interrupt status register. Under high load NAPI may not be
able to process all data (work_done == budget) and it will schedule
subsequent calls to the poll callback.
rtl_ack_events() however resets the bits in the interrupt status
register, therefore subsequent calls to rtl8169_poll() won't call
rtl_rx() and rtl_tx() - chip interrupts are still disabled.

Fix this by calling rtl_rx() and rtl_tx() independent of the bits
set in the interrupt status register. Both functions will detect
if there's nothing to do for them.

Fixes: da78dbff ("r8169: remove work from irq handler.")
Signed-off-by: default avatarHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      6b839b6c
    • David S. Miller's avatar
      sparc: Revert unintended perf changes. · 27faeebd
      David S. Miller authored 
      Some local debugging hacks accidently slipped into the VDSO commit.

Sorry!
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      27faeebd
    • Leo Li's avatar
      drm: Get ref on CRTC commit object when waiting for flip_done · 4364bcb2
      Leo Li authored 
      This fixes a general protection fault, caused by accessing the contents
of a flip_done completion object that has already been freed. It occurs
due to the preemption of a non-blocking commit worker thread W by
another commit thread X. X continues to clear its atomic state at the
end, destroying the CRTC commit object that W still needs. Switching
back to W and accessing the commit objects then leads to bad results.

Worker W becomes preemptable when waiting for flip_done to complete. At
this point, a frequently occurring commit thread X can take over. Here's
an example where W is a worker thread that flips on both CRTCs, and X
does a legacy cursor update on both CRTCs:

        ...
     1. W does flip work
     2. W runs commit_hw_done()
     3. W waits for flip_done on CRTC 1
     4. > flip_done for CRTC 1 completes
     5. W finishes waiting for CRTC 1
     6. W waits for flip_done on CRTC 2

     7. > Preempted by X
     8. > flip_done for CRTC 2 completes
     9. X atomic_check: hw_done and flip_done are complete on all CRTCs
    10. X updates cursor on both CRTCs
    11. X destroys atomic state
    12. X done

    13. > Switch back to W
    14. W waits for flip_done on CRTC 2
    15. W raises general protection fault

The error looks like so:

    general protection fault: 0000 [#1] PREEMPT SMP PTI
    **snip**
    Call Trace:
     lock_acquire+0xa2/0x1b0
     _raw_spin_lock_irq+0x39/0x70
     wait_for_completion_timeout+0x31/0x130
     drm_atomic_helper_wait_for_flip_done+0x64/0x90 [drm_kms_helper]
     amdgpu_dm_atomic_commit_tail+0xcae/0xdd0 [amdgpu]
     commit_tail+0x3d/0x70 [drm_kms_helper]
     process_one_work+0x212/0x650
     worker_thread+0x49/0x420
     kthread+0xfb/0x130
     ret_from_fork+0x3a/0x50
    Modules linked in: x86_pkg_temp_thermal amdgpu(O) chash(O)
    gpu_sched(O) drm_kms_helper(O) syscopyarea sysfillrect sysimgblt
    fb_sys_fops ttm(O) drm(O)

Note that i915 has this issue masked, since hw_done is signaled after
waiting for flip_done. Doing so will block the cursor update from
happening until hw_done is signaled, preventing the cursor commit from
destroying the state.

v2: The reference on the commit object needs to be obtained before
    hw_done() is signaled, since that's the point where another commit
    is allowed to modify the state. Assuming that the
    new_crtc_state->commit object still exists within flip_done() is
    incorrect.

    Fix by getting a reference in setup_commit(), and releasing it
    during default_clear().
Signed-off-by: default avatarLeo Li <sunpeng.li@amd.com>
Reviewed-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: default avatarHarry Wentland <harry.wentland@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1539611200-6184-1-git-send-email-sunpeng.li@amd.com
      4364bcb2
    • David S. Miller's avatar
      Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec · 2ee653f6
      David S. Miller authored 
      Steffen Klassert says:

====================
pull request (net): ipsec 2018-10-18

1) Free the xfrm interface gro_cells when deleting the
   interface, otherwise we leak it. From Li RongQing.

2) net/core/flow.c does not exist anymore, so remove it
   from the MAINTAINERS file.

3) Fix a slab-out-of-bounds in _decode_session6.
   From Alexei Starovoitov.

4) Fix RCU protection when policies inserted into
   thei bydst lists. From Florian Westphal.

Please pull or let me know if there are problems.
====================
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      2ee653f6
    • Ming Lei's avatar
      block: don't deal with discard limit in blkdev_issue_discard() · 744889b7
      Ming Lei authored 
      blk_queue_split() does respect this limit via bio splitting, so no
need to do that in blkdev_issue_discard(), then we can align to
normal bio submit(bio_add_page() & submit_bio()).

More importantly, this patch fixes one issue introduced in a22c4d7e
("block: re-add discard_granularity and alignment checks"), in which
zero discard bio may be generated in case of zero alignment.

Fixes: a22c4d7e ("block: re-add discard_granularity and alignment checks")
Cc: stable@vger.kernel.org
Cc: Ming Lin <ming.l@ssi.samsung.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Xiao Ni <xni@redhat.com>
Tested-by: default avatarMariusz Dabrowski <mariusz.dabrowski@intel.com>
Signed-off-by: default avatarMing Lei <ming.lei@redhat.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
      744889b7
    • Eric Sandeen's avatar
      fscache: Fix out of bound read in long cookie keys · fa520c47
      Eric Sandeen authored 
      fscache_set_key() can incur an out-of-bounds read, reported by KASAN:

 BUG: KASAN: slab-out-of-bounds in fscache_alloc_cookie+0x5b3/0x680 [fscache]
 Read of size 4 at addr ffff88084ff056d4 by task mount.nfs/32615

and also reported by syzbot at https://lkml.org/lkml/2018/7/8/236

  BUG: KASAN: slab-out-of-bounds in fscache_set_key fs/fscache/cookie.c:120 [inline]
  BUG: KASAN: slab-out-of-bounds in fscache_alloc_cookie+0x7a9/0x880 fs/fscache/cookie.c:171
  Read of size 4 at addr ffff8801d3cc8bb4 by task syz-executor907/4466

This happens for any index_key_len which is not divisible by 4 and is
larger than the size of the inline key, because the code allocates exactly
index_key_len for the key buffer, but the hashing loop is stepping through
it 4 bytes (u32) at a time in the buf[] array.

Fix this by calculating how many u32 buffers we'll need by using
DIV_ROUND_UP, and then using kcalloc() to allocate a precleared allocation
buffer to hold the index_key, then using that same count as the hashing
index limit.

Fixes: ec0328e4 ("fscache: Maintain a catalogue of allocated cookies")
Reported-by: syzbot+a95b989b2dde8e806af8@syzkaller.appspotmail.com
Signed-off-by: default avatarEric Sandeen <sandeen@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      fa520c47
    • David Howells's avatar
      fscache: Fix incomplete initialisation of inline key space · 1ff22883
      David Howells authored 
      The inline key in struct rxrpc_cookie is insufficiently initialized,
zeroing only 3 of the 4 slots, therefore an index_key_len between 13 and 15
bytes will end up hashing uninitialized memory because the memcpy only
partially fills the last buf[] element.

Fix this by clearing fscache_cookie objects on allocation rather than using
the slab constructor to initialise them.  We're going to pretty much fill
in the entire struct anyway, so bringing it into our dcache writably
shouldn't incur much overhead.

This removes the need to do clearance in fscache_set_key() (where we aren't
doing it correctly anyway).

Also, we don't need to set cookie->key_len in fscache_set_key() as we
already did it in the only caller, so remove that.

Fixes: ec0328e4 ("fscache: Maintain a catalogue of allocated cookies")
Reported-by: syzbot+a95b989b2dde8e806af8@syzkaller.appspotmail.com
Reported-by: default avatarEric Sandeen <sandeen@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      1ff22883
    • Al Viro's avatar
      cachefiles: fix the race between cachefiles_bury_object() and rmdir(2) · 169b8033
      Al Viro authored 
      the victim might've been rmdir'ed just before the lock_rename();
unlike the normal callers, we do not look the source up after the
parents are locked - we know it beforehand and just recheck that it's
still the child of what used to be its parent.  Unfortunately,
the check is too weak - we don't spot a dead directory since its
->d_parent is unchanged, dentry is positive, etc.  So we sail all
the way to ->rename(), with hosting filesystems _not_ expecting
to be asked renaming an rmdir'ed subdirectory.

The fix is easy, fortunately - the lock on parent is sufficient for
making IS_DEADDIR() on child safe.

Cc: stable@vger.kernel.org
Fixes: 9ae326a6 (CacheFiles: A cache that backs onto a mounted filesystem)
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      169b8033
    • Linus Torvalds's avatar
      mremap: properly flush TLB before releasing the page · eb66ae03
      Linus Torvalds authored 
      Jann Horn points out that our TLB flushing was subtly wrong for the
mremap() case.  What makes mremap() special is that we don't follow the
usual "add page to list of pages to be freed, then flush tlb, and then
free pages".  No, mremap() obviously just _moves_ the page from one page
table location to another.

That matters, because mremap() thus doesn't directly control the
lifetime of the moved page with a freelist: instead, the lifetime of the
page is controlled by the page table locking, that serializes access to
the entry.

As a result, we need to flush the TLB not just before releasing the lock
for the source location (to avoid any concurrent accesses to the entry),
but also before we release the destination page table lock (to avoid the
TLB being flushed after somebody else has already done something to that
page).

This also makes the whole "need_flush" logic unnecessary, since we now
always end up flushing the TLB for every valid entry.
Reported-and-tested-by: default avatarJann Horn <jannh@google.com>
Acked-by: default avatarWill Deacon <will.deacon@arm.com>
Tested-by: default avatarIngo Molnar <mingo@kernel.org>
Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      eb66ae03
    • Christoph Hellwig's avatar
      LICENSES: Remove CC-BY-SA-4.0 license text · 19e6420e
      Christoph Hellwig authored 
      Using non-GPL licenses for our documentation is rather problematic,
as it can directly include other files, which generally are GPLv2
licensed and thus not compatible.

Remove this license now that the only user (idr.rst) is gone to avoid
people semi-accidentally using it again.
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      19e6420e
    • Greg Kroah-Hartman's avatar
      Merge branch 'ida-fixes-4.19-rc8' of git://git.infradead.org/users/willy/linux-dax · ca9f672f
      Greg Kroah-Hartman authored 
      Matthew writes:
  "IDA/IDR fixes for 4.19

   I have two tiny fixes, one for the IDA test-suite and one for the IDR
   documentation license."

* 'ida-fixes-4.19-rc8' of git://git.infradead.org/users/willy/linux-dax:
  idr: Change documentation license
  test_ida: Fix lockdep warning
      ca9f672f
    • Ingo Molnar's avatar
      Merge tag 'perf-urgent-for-mingo-4.19-20181017' of... · 20e8e72d
      Ingo Molnar authored 
      Merge tag 'perf-urgent-for-mingo-4.19-20181017' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

- Stop falling back to kallsyms for vDSO symbols lookup, this wasn't
  being really used and is not valid in arches such as Sparc, where
  user and kernel space don't share the address space, relying only on
  cpumode to figure out what DSOs to lookup (Arnaldo Carvalho de Melo)

- Align CPU map synthesized events properly, fixing SIGBUS in
  CPUs like Sparc (David Miller)

- Fix use of alternatives to find JDIR (Jarod Wilson)

- Store IDs for events with their own CPUs when synthesizing user
  level event details (scale, unit, etc) events, fixing a crash
  when recording a PMU event with a cpumask defined (Jiri Olsa)

- Fix wrong filter_band* values for uncore Intel vendor events (Jiri Olsa)

- Fix detection of tracefs path in systems without tracefs, where
  that path should be the debugfs mountpoint plus "/tracing/" (Jiri Olsa)

- Pass build flags to traceevent build, allowing using alternative
  flags in distro packages, RPM, for instance (Jiri Olsa)

- Fix 'perf report' crash on invalid inline debug information (Milian Wolff)

- Synch KVM UAPI copies (Arnaldo Carvalho de Melo)
Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
      20e8e72d
    • Nikolay Aleksandrov's avatar
      net: ipmr: fix unresolved entry dumps · eddf016b
      Nikolay Aleksandrov authored 
      If the skb space ends in an unresolved entry while dumping we'll miss
some unresolved entries. The reason is due to zeroing the entry counter
between dumping resolved and unresolved mfc entries. We should just
keep counting until the whole table is dumped and zero when we move to
the next as we have a separate table counter.
Reported-by: default avatarColin Ian King <colin.king@canonical.com>
Fixes: 8fb472c0 ("ipmr: improve hash scalability")
Signed-off-by: default avatarNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      eddf016b
    • Gregory CLEMENT's avatar
      net: mscc: ocelot: Fix comment in ocelot_vlant_wait_for_completion() · 06a36ecb
      Gregory CLEMENT authored 
      The ocelot_vlant_wait_for_completion() function is very similar to the
ocelot_mact_wait_for_completion(). It seemed to have be copied but the
comment was not updated, so let's fix it.
Signed-off-by: default avatarGregory CLEMENT <gregory.clement@bootlin.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      06a36ecb
    • Xin Long's avatar
      sctp: fix the data size calculation in sctp_data_size · 5660b9d9
      Xin Long authored 
      sctp data size should be calculated by subtracting data chunk header's
length from chunk_hdr->length, not just data header.

Fixes: 668c9beb ("sctp: implement assign_number for sctp_stream_interleave")
Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
Acked-by: default avatarMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      5660b9d9
    • Ake Koomsin's avatar
      virtio_net: avoid using netif_tx_disable() for serializing tx routine · 05c998b7
      Ake Koomsin authored 
      Commit 713a98d9 ("virtio-net: serialize tx routine during reset")
introduces netif_tx_disable() after netif_device_detach() in order to
avoid use-after-free of tx queues. However, there are two issues.

1) Its operation is redundant with netif_device_detach() in case the
   interface is running.
2) In case of the interface is not running before suspending and
   resuming, the tx does not get resumed by netif_device_attach().
   This results in losing network connectivity.

It is better to use netif_tx_lock_bh()/netif_tx_unlock_bh() instead for
serializing tx routine during reset. This also preserves the symmetry
of netif_device_detach() and netif_device_attach().

Fixes commit 713a98d9 ("virtio-net: serialize tx routine during reset")
Signed-off-by: default avatarAke Koomsin <ake@igel.co.jp>
Acked-by: default avatarJason Wang <jasowang@redhat.com>
Acked-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      05c998b7
    • Greg Kroah-Hartman's avatar
      Merge tag 'trace-v4.19-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace · 9bd871df
      Greg Kroah-Hartman authored 
      Steven writes:
  "tracing: Two fixes for 4.19

   This fixes two bugs:
    - Fix size mismatch of tracepoint array
    - Have preemptirq test module use same clock source of the selftest"

* tag 'trace-v4.19-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Use trace_clock_local() for looping in preemptirq_delay_test.c
  tracepoint: Fix tracepoint array element size mismatch
      9bd871df
    • Paolo Abeni's avatar
      udp6: fix encap return code for resubmitting · 84dad559
      Paolo Abeni authored 
      The commit eb63f296 ("udp6: add missing checks on edumux packet
processing") used the same return code convention of the ipv4 counterpart,
but ipv6 uses the opposite one: positive values means resubmit.

This change addresses the issue, using positive return value for
resubmitting. Also update the related comment, which was broken, too.

Fixes: eb63f296 ("udp6: add missing checks on edumux packet processing")
Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      84dad559
    • Ido Schimmel's avatar
      mlxsw: core: Fix use-after-free when flashing firmware during init · 9b3bc7db
      Ido Schimmel authored 
      When the switch driver (e.g., mlxsw_spectrum) determines it needs to
flash a new firmware version it resets the ASIC after the flashing
process. The bus driver (e.g., mlxsw_pci) then registers itself again
with mlxsw_core which means (among other things) that the device
registers itself again with the hwmon subsystem again.

Since the device was registered with the hwmon subsystem using
devm_hwmon_device_register_with_groups(), then the old hwmon device
(registered before the flashing) was never unregistered and was
referencing stale data, resulting in a use-after free.

Fix by removing reliance on device managed APIs in mlxsw_hwmon_init().

Fixes: c86d62cc ("mlxsw: spectrum: Reset FW after flash")
Signed-off-by: default avatarIdo Schimmel <idosch@mellanox.com>
Reported-by: default avatarAlexander Petrovskiy <alexpe@mellanox.com>
Tested-by: default avatarAlexander Petrovskiy <alexpe@mellanox.com>
Reviewed-by: default avatarPetr Machata <petrm@mellanox.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      9b3bc7db
    • Xin Long's avatar
      sctp: not free the new asoc when sctp_wait_for_connect returns err · c863850c
      Xin Long authored 
      When sctp_wait_for_connect is called to wait for connect ready
for sp->strm_interleave in sctp_sendmsg_to_asoc, a panic could
be triggered if cpu is scheduled out and the new asoc is freed
elsewhere, as it will return err and later the asoc gets freed
again in sctp_sendmsg.

[  285.840764] list_del corruption, ffff9f0f7b284078->next is LIST_POISON1 (dead000000000100)
[  285.843590] WARNING: CPU: 1 PID: 8861 at lib/list_debug.c:47 __list_del_entry_valid+0x50/0xa0
[  285.846193] Kernel panic - not syncing: panic_on_warn set ...
[  285.846193]
[  285.848206] CPU: 1 PID: 8861 Comm: sctp_ndata Kdump: loaded Not tainted 4.19.0-rc7.label #584
[  285.850559] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[  285.852164] Call Trace:
...
[  285.872210]  ? __list_del_entry_valid+0x50/0xa0
[  285.872894]  sctp_association_free+0x42/0x2d0 [sctp]
[  285.873612]  sctp_sendmsg+0x5a4/0x6b0 [sctp]
[  285.874236]  sock_sendmsg+0x30/0x40
[  285.874741]  ___sys_sendmsg+0x27a/0x290
[  285.875304]  ? __switch_to_asm+0x34/0x70
[  285.875872]  ? __switch_to_asm+0x40/0x70
[  285.876438]  ? ptep_set_access_flags+0x2a/0x30
[  285.877083]  ? do_wp_page+0x151/0x540
[  285.877614]  __sys_sendmsg+0x58/0xa0
[  285.878138]  do_syscall_64+0x55/0x180
[  285.878669]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

This is a similar issue with the one fixed in Commit ca3af4dd
("sctp: do not free asoc when it is already dead in sctp_sendmsg").
But this one can't be fixed by returning -ESRCH for the dead asoc
in sctp_wait_for_connect, as it will break sctp_connect's return
value to users.

This patch is to simply set err to -ESRCH before it returns to
sctp_sendmsg when any err is returned by sctp_wait_for_connect
for sp->strm_interleave, so that no asoc would be freed due to
this.

When users see this error, they will know the packet hasn't been
sent. And it also makes sense to not free asoc because waiting
connect fails, like the second call for sctp_wait_for_connect in
sctp_sendmsg_to_asoc.

Fixes: 668c9beb ("sctp: implement assign_number for sctp_stream_interleave")
Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
Acked-by: default avatarMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      c863850c
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7