Commit Graph

768538 Commits

Author SHA1 Message Date
Tomas Bortoli
430ac66eb4 net/9p/trans_fd.c: fix race-condition by flushing workqueue before the kfree()
The patch adds the flush in p9_mux_poll_stop() as it the function used by
p9_conn_destroy(), in turn called by p9_fd_close() to stop the async
polling associated with the data regarding the connection.

Link: http://lkml.kernel.org/r/20180720092730.27104-1-tomasbortoli@gmail.com
Signed-off-by: Tomas Bortoli <tomasbortoli@gmail.com>
Reported-by: syzbot+39749ed7d9ef6dfb23f6@syzkaller.appspotmail.com
To: Eric Van Hensbergen <ericvh@gmail.com>
To: Ron Minnich <rminnich@sandia.gov>
To: Latchesar Ionkov <lucho@ionkov.net>
Cc: Yiwen Jiang <jiangyiwen@huwei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:34:58 +09:00
jiangyiwen
31934da810 net/9p/virtio: Fix hard lockup in req_done
When client has multiple threads that issue io requests
all the time, and the server has a very good performance,
it may cause cpu is running in the irq context for a long
time because it can check virtqueue has buf in the *while*
loop.

So we should keep chan->lock in the whole loop.

[ Dominique: reworded subject line ]
Link: http://lkml.kernel.org/r/5B503AEC.5080404@huawei.com
Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com>
To: Andrew Morton <akpm@linux-foundation.org>
To: Eric Van Hensbergen <ericvh@gmail.com>
To: Ron Minnich <rminnich@sandia.gov>
To: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:34:58 +09:00
piaojun
c7ebbae7cf net/9p/trans_virtio.c: fix some spell mistakes in comments
Fix spelling mistake in comments of p9_virtio_zc_request().

Link: http://lkml.kernel.org/r/5B4EB7D9.9010108@huawei.com
Signed-off-by: Jun Piao <piaojun@huawei.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:34:58 +09:00
Chirantan Ekbote
d28c756cae 9p/net: Fix zero-copy path in the 9p virtio transport
The zero-copy optimization when reading or writing large chunks of data
is quite useful.  However, the 9p messages created through the zero-copy
write path have an incorrect message size: it should be the size of the
header + size of the data being written but instead it's just the size
of the header.

This only works if the server ignores the size field of the message and
otherwise breaks the framing of the protocol. Fix this by re-writing the
message size field with the correct value.

Tested by running `dd if=/dev/zero of=out bs=4k count=1` inside a
virtio-9p mount.

Link: http://lkml.kernel.org/r/20180717003529.114368-1-chirantan@chromium.org
Signed-off-by: Chirantan Ekbote <chirantan@chromium.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
Cc: Dylan Reid <dgreid@chromium.org>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:34:59 +09:00
Matthew Wilcox
2557d0c57c 9p: Embed wait_queue_head into p9_req_t
On a 64-bit system, the wait_queue_head_t is 24 bytes while the pointer
to it is 8 bytes.  Growing the p9_req_t by 16 bytes is better than
performing a 24-byte memory allocation.

Link: http://lkml.kernel.org/r/20180711210225.19730-5-willy@infradead.org
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:21:44 +09:00
Matthew Wilcox
f28cdf0430 9p: Replace the fidlist with an IDR
The p9_idpool being used to allocate the IDs uses an IDR to allocate
the IDs ... which we then keep in a doubly-linked list, rather than in
the IDR which allocated them.  We can use an IDR directly which saves
two pointers per p9_fid, and a tiny memory allocation per p9_client.

Link: http://lkml.kernel.org/r/20180711210225.19730-4-willy@infradead.org
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:21:44 +09:00
Matthew Wilcox
b5303be2be 9p: Change p9_fid_create calling convention
Return NULL instead of ERR_PTR when we can't allocate a FID.  The ENOSPC
return value was getting all the way back to userspace, and that's
confusing for a userspace program which isn't expecting read() to tell it
there's no space left on the filesystem.  The best error we can return to
indicate a temporary failure caused by lack of client resources is ENOMEM.

Maybe it would be better to sleep until a FID is available, but that's
not a change I'm comfortable making.

Link: http://lkml.kernel.org/r/20180711210225.19730-3-willy@infradead.org
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Jun Piao <piaojun@huawei.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Yiwen Jiang <jiangyiwen@huwei.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:21:44 +09:00
Matthew Wilcox
2d58f63f72 9p: Fix comment on smp_wmb
The previous comment misled me into thinking the barrier wasn't needed
at all.

Link: http://lkml.kernel.org/r/20180711210225.19730-2-willy@infradead.org
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:21:44 +09:00
Tomas Bortoli
7913690dcc net/9p/client.c: version pointer uninitialized
The p9_client_version() does not initialize the version pointer. If the
call to p9pdu_readf() returns an error and version has not been allocated
in p9pdu_readf(), then the program will jump to the "error" label and will
try to free the version pointer. If version is not initialized, free()
will be called with uninitialized, garbage data and will provoke a crash.

Link: http://lkml.kernel.org/r/20180709222943.19503-1-tomasbortoli@gmail.com
Signed-off-by: Tomas Bortoli <tomasbortoli@gmail.com>
Reported-by: syzbot+65c6b72f284a39d416b4@syzkaller.appspotmail.com
Reviewed-by: Jun Piao <piaojun@huawei.com>
Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:21:44 +09:00
Colin Ian King
6baaac0961 fs/9p/v9fs.c: fix spelling mistake "Uknown" -> "Unknown"
fix spelling mistake in pr_info message text

Link: http://lkml.kernel.org/r/20180526150650.10562-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:21:44 +09:00
Jean-Philippe Brucker
92aef4675d net/9p: fix error path of p9_virtio_probe
Currently when virtio_find_single_vq fails, we go through del_vqs which
throws a warning (Trying to free already-free IRQ).  Skip del_vqs if vq
allocation failed.

Link: http://lkml.kernel.org/r/20180524101021.49880-1-jean-philippe.brucker@arm.com
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:21:44 +09:00
piaojun
b87d1d2652 9p/net/protocol.c: return -ENOMEM when kmalloc() failed
We should return -ENOMEM to upper user when kmalloc failed to indicate
accurate errno.

Link: http://lkml.kernel.org/r/5B4552C5.60000@huawei.com
Signed-off-by: Jun Piao <piaojun@huawei.com>
Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:21:44 +09:00
piaojun
64ad31f328 net/9p/client.c: add missing '\n' at the end of p9_debug()
In p9_client_getattr_dotl(), we should add '\n' at the end of printing
log.

Link: http://lkml.kernel.org/r/5B44589A.50302@huawei.com
Signed-off-by: Jun Piao <piaojun@huawei.com>
Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:21:44 +09:00
Souptick Joarder
fe6340e2d1 fs/9p/vfs_file.c: use new return type vm_fault_t
Use new return type vm_fault_t for page_mkwrite handler.

See 1c8f422059 ("mm: change return type to vm_fault_t") for reference.

Link: http://lkml.kernel.org/r/20180702154928.GA3964@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Jun Piao <piaojun@huawei.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
2018-08-13 09:21:44 +09:00
Linus Torvalds
94710cac0e Linux 4.18 2018-08-12 13:41:04 -07:00
Linus Torvalds
921195d356 SCSI fixes on 20180811
Eight fixes.  The most important one is the mpt3sas fix which makes
 the driver work again on big endian systems.  The rest are mostly
 minor error path or checker issues and the vmw_scsi one fixes a
 performance problem.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.vnet.ibm.com>
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Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "Eight fixes.

  The most important one is the mpt3sas fix which makes the driver work
  again on big endian systems. The rest are mostly minor error path or
  checker issues and the vmw_scsi one fixes a performance problem"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: vmw_pvscsi: Return DID_RESET for status SAM_STAT_COMMAND_TERMINATED
  scsi: sr: Avoid that opening a CD-ROM hangs with runtime power management enabled
  scsi: mpt3sas: Swap I/O memory read value back to cpu endianness
  scsi: fcoe: clear FC_RP_STARTED flags when receiving a LOGO
  scsi: fcoe: drop frames in ELS LOGO error path
  scsi: fcoe: fix use-after-free in fcoe_ctlr_els_send
  scsi: qedi: Fix a potential buffer overflow
  scsi: qla2xxx: Fix memory leak for allocating abort IOCB
2018-08-12 12:52:05 -07:00
Linus Torvalds
b5b1404d08 init: rename and re-order boot_cpu_state_init()
This is purely a preparatory patch for upcoming changes during the 4.19
merge window.

We have a function called "boot_cpu_state_init()" that isn't really
about the bootup cpu state: that is done much earlier by the similarly
named "boot_cpu_init()" (note lack of "state" in name).

This function initializes some hotplug CPU state, and needs to run after
the percpu data has been properly initialized.  It even has a comment to
that effect.

Except it _doesn't_ actually run after the percpu data has been properly
initialized.  On x86 it happens to do that, but on at least arm and
arm64, the percpu base pointers are initialized by the arch-specific
'smp_prepare_boot_cpu()' hook, which ran _after_ boot_cpu_state_init().

This had some unexpected results, and in particular we have a patch
pending for the merge window that did the obvious cleanup of using
'this_cpu_write()' in the cpu hotplug init code:

  -       per_cpu_ptr(&cpuhp_state, smp_processor_id())->state = CPUHP_ONLINE;
  +       this_cpu_write(cpuhp_state.state, CPUHP_ONLINE);

which is obviously the right thing to do.  Except because of the
ordering issue, it actually failed miserably and unexpectedly on arm64.

So this just fixes the ordering, and changes the name of the function to
be 'boot_cpu_hotplug_init()' to make it obvious that it's about cpu
hotplug state, because the core CPU state was supposed to have already
been done earlier.

Marked for stable, since the (not yet merged) patch that will show this
problem is marked for stable.

Reported-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-12 12:19:42 -07:00
Linus Torvalds
d6dd643159 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
 "A bunch of race fixes, mostly around lazy pathwalk.

  All of it is -stable fodder, a large part going back to 2013"

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  make sure that __dentry_kill() always invalidates d_seq, unhashed or not
  fix __legitimize_mnt()/mntput() race
  fix mntput/mntput race
  root dentries need RCU-delayed freeing
2018-08-12 11:21:17 -07:00
Linus Torvalds
ec0c96714e Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "Last bit of straggler fixes...

  1) Fix btf library licensing to LGPL, from Martin KaFai lau.

  2) Fix error handling in bpf sockmap code, from Daniel Borkmann.

  3) XDP cpumap teardown handling wrt. execution contexts, from Jesper
     Dangaard Brouer.

  4) Fix loss of runtime PM on failed vlan add/del, from Ivan
     Khoronzhuk.

  5) xen-netfront caches skb_shinfo(skb) across a __pskb_pull_tail()
     call, which potentially changes the skb's data buffer, and thus
     skb_shinfo(). Fix from Juergen Gross"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  xen/netfront: don't cache skb_shinfo()
  net: ethernet: ti: cpsw: fix runtime_pm while add/kill vlan
  net: ethernet: ti: cpsw: clear all entries when delete vid
  xdp: fix bug in devmap teardown code path
  samples/bpf: xdp_redirect_cpu adjustment to reproduce teardown race easier
  xdp: fix bug in cpumap teardown code path
  bpf, sockmap: fix cork timeout for select due to epipe
  bpf, sockmap: fix leak in bpf_tcp_sendmsg wait for mem path
  bpf, sockmap: fix bpf_tcp_sendmsg sock error handling
  bpf: btf: Change tools/lib/bpf/btf to LGPL
2018-08-11 11:22:44 -07:00
Juergen Gross
d472b3a6cf xen/netfront: don't cache skb_shinfo()
skb_shinfo() can change when calling __pskb_pull_tail(): Don't cache
its return value.

Cc: stable@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-11 09:41:58 -07:00
David S. Miller
556fdd857f Merge branch 'cpsw-runtime-pm-fix'
Grygorii Strashko says:

====================
net: ethernet: ti: cpsw: fix runtime pm while add/del reserved vid

Here 2 not critical fixes for:
- vlan ale table leak while error if deleting vlan (simplifies next fix)
- runtime pm while try to set reserved vlan
====================

Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-11 09:38:53 -07:00
Ivan Khoronzhuk
803c4f64d7 net: ethernet: ti: cpsw: fix runtime_pm while add/kill vlan
It's exclusive with normal behaviour but if try to set vlan to one of
the reserved values is made, the cpsw runtime pm is broken.

Fixes: a6c5d14f51 ("drivers: net: cpsw: ndev: fix accessing to suspended device")
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-11 09:38:53 -07:00
Ivan Khoronzhuk
be35b982e8 net: ethernet: ti: cpsw: clear all entries when delete vid
In cases if some of the entries were not found in forwarding table
while killing vlan, the rest not needed entries still left in the
table. No need to stop, as entry was deleted anyway. So fix this by
returning error only after all was cleaned. To implement this, return
-ENOENT in cpsw_ale_del_mcast() as it's supposed to be.

Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-11 09:38:53 -07:00
Minchan Kim
4f7a7beaee zram: remove BD_CAP_SYNCHRONOUS_IO with writeback feature
If zram supports writeback feature, it's no longer a
BD_CAP_SYNCHRONOUS_IO device beause zram does asynchronous IO operations
for incompressible pages.

Do not pretend to be synchronous IO device.  It makes the system very
sluggish due to waiting for IO completion from upper layers.

Furthermore, it causes a user-after-free problem because swap thinks the
opearion is done when the IO functions returns so it can free the page
(e.g., lock_page_or_retry and goto out_release in do_swap_page) but in
fact, IO is asynchronous so the driver could access a just freed page
afterward.

This patch fixes the problem.

  BUG: Bad page state in process qemu-system-x86  pfn:3dfab21
  page:ffffdfb137eac840 count:0 mapcount:0 mapping:0000000000000000 index:0x1
  flags: 0x17fffc000000008(uptodate)
  raw: 017fffc000000008 dead000000000100 dead000000000200 0000000000000000
  raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
  page dumped because: PAGE_FLAGS_CHECK_AT_PREP flag set
  bad because of flags: 0x8(uptodate)
  CPU: 4 PID: 1039 Comm: qemu-system-x86 Tainted: G    B 4.18.0-rc5+ #1
  Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0b 05/02/2017
  Call Trace:
    dump_stack+0x5c/0x7b
    bad_page+0xba/0x120
    get_page_from_freelist+0x1016/0x1250
    __alloc_pages_nodemask+0xfa/0x250
    alloc_pages_vma+0x7c/0x1c0
    do_swap_page+0x347/0x920
    __handle_mm_fault+0x7b4/0x1110
    handle_mm_fault+0xfc/0x1f0
    __get_user_pages+0x12f/0x690
    get_user_pages_unlocked+0x148/0x1f0
    __gfn_to_pfn_memslot+0xff/0x3c0 [kvm]
    try_async_pf+0x87/0x230 [kvm]
    tdp_page_fault+0x132/0x290 [kvm]
    kvm_mmu_page_fault+0x74/0x570 [kvm]
    kvm_arch_vcpu_ioctl_run+0x9b3/0x1990 [kvm]
    kvm_vcpu_ioctl+0x388/0x5d0 [kvm]
    do_vfs_ioctl+0xa2/0x630
    ksys_ioctl+0x70/0x80
    __x64_sys_ioctl+0x16/0x20
    do_syscall_64+0x55/0x100
    entry_SYSCALL_64_after_hwframe+0x44/0xa9

Link: https://lore.kernel.org/lkml/0516ae2d-b0fd-92c5-aa92-112ba7bd32fc@contabo.de/
Link: http://lkml.kernel.org/r/20180802051112.86174-1-minchan@kernel.org
[minchan@kernel.org: fix changelog, add comment]
 Link: https://lore.kernel.org/lkml/0516ae2d-b0fd-92c5-aa92-112ba7bd32fc@contabo.de/
 Link: http://lkml.kernel.org/r/20180802051112.86174-1-minchan@kernel.org
 Link: http://lkml.kernel.org/r/20180805233722.217347-1-minchan@kernel.org
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: Tino Lehnig <tino.lehnig@contabo.de>
Tested-by: Tino Lehnig <tino.lehnig@contabo.de>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@vger.kernel.org>	[4.15+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-10 20:19:59 -07:00
jie@chenjie6@huwei.com
24eee1e4c4 mm/memory.c: check return value of ioremap_prot
ioremap_prot() can return NULL which could lead to an oops.

Link: http://lkml.kernel.org/r/1533195441-58594-1-git-send-email-chenjie6@huawei.com
Signed-off-by: chen jie <chenjie6@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: chenjie <chenjie6@huawei.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-10 20:19:58 -07:00
Andrey Ryabinin
3ca17b1f36 lib/ubsan: remove null-pointer checks
With gcc-8 fsanitize=null become very noisy.  GCC started to complain
about things like &a->b, where 'a' is NULL pointer.  There is no NULL
dereference, we just calculate address to struct member.  It's
technically undefined behavior so UBSAN is correct to report it.  But as
long as there is no real NULL-dereference, I think, we should be fine.

-fno-delete-null-pointer-checks compiler flag should protect us from any
consequences.  So let's just no use -fsanitize=null as it's not useful
for us.  If there is a real NULL-deref we will see crash.  Even if
userspace mapped something at NULL (root can do this), with things like
SMAP should catch the issue.

Link: http://lkml.kernel.org/r/20180802153209.813-1-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-10 20:19:58 -07:00
Kieran Bingham
5832fcf999 MAINTAINERS: GDB: update e-mail address
This entry was created with my personal e-mail address.  Update this entry
to my open-source kernel.org account.

Link: http://lkml.kernel.org/r/20180806143904.4716-4-kieran.bingham@ideasonboard.com
Signed-off-by: Kieran Bingham <kbingham@kernel.org>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-10 20:19:58 -07:00
Linus Torvalds
f313b43be4 Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c fix from Wolfram Sang:
 "A single driver bugfix for I2C.

  The bug was found by systematically stress testing the driver, so I am
  confident to merge it that late in the cycle although it is probably
  unusually large"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: xlp9xx: Fix case where SSIF read transaction completes early
2018-08-10 10:04:56 -07:00
David S. Miller
e91e218946 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2018-08-10

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

The main changes are:

1) Fix cpumap and devmap on teardown as they're under RCU context
   and won't have same assumption as running under NAPI protection,
   from Jesper.

2) Fix various sockmap bugs in bpf_tcp_sendmsg() code, e.g. we had
   a bug where socket error was not propagated correctly, from Daniel.

3) Fix incompatible libbpf header license for BTF code and match it
   before it gets officially released with the rest of libbpf which
   is LGPL-2.1, from Martin.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-09 23:18:29 -07:00
Al Viro
4c0d7cd5c8 make sure that __dentry_kill() always invalidates d_seq, unhashed or not
RCU pathwalk relies upon the assumption that anything that changes
->d_inode of a dentry will invalidate its ->d_seq.  That's almost
true - the one exception is that the final dput() of already unhashed
dentry does *not* touch ->d_seq at all.  Unhashing does, though,
so for anything we'd found by RCU dcache lookup we are fine.
Unfortunately, we can *start* with an unhashed dentry or jump into
it.

We could try and be careful in the (few) places where that could
happen.  Or we could just make the final dput() invalidate the damn
thing, unhashed or not.  The latter is much simpler and easier to
backport, so let's do it that way.

Reported-by: "Dae R. Jeong" <threeearcat@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-08-09 18:07:15 -04:00
Al Viro
119e1ef80e fix __legitimize_mnt()/mntput() race
__legitimize_mnt() has two problems - one is that in case of success
the check of mount_lock is not ordered wrt preceding increment of
refcount, making it possible to have successful __legitimize_mnt()
on one CPU just before the otherwise final mntpu() on another,
with __legitimize_mnt() not seeing mntput() taking the lock and
mntput() not seeing the increment done by __legitimize_mnt().
Solved by a pair of barriers.

Another is that failure of __legitimize_mnt() on the second
read_seqretry() leaves us with reference that'll need to be
dropped by caller; however, if that races with final mntput()
we can end up with caller dropping rcu_read_lock() and doing
mntput() to release that reference - with the first mntput()
having freed the damn thing just as rcu_read_lock() had been
dropped.  Solution: in "do mntput() yourself" failure case
grab mount_lock, check if MNT_DOOMED has been set by racing
final mntput() that has missed our increment and if it has -
undo the increment and treat that as "failure, caller doesn't
need to drop anything" case.

It's not easy to hit - the final mntput() has to come right
after the first read_seqretry() in __legitimize_mnt() *and*
manage to miss the increment done by __legitimize_mnt() before
the second read_seqretry() in there.  The things that are almost
impossible to hit on bare hardware are not impossible on SMP
KVM, though...

Reported-by: Oleg Nesterov <oleg@redhat.com>
Fixes: 48a066e72d ("RCU'd vsfmounts")
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-08-09 17:51:32 -04:00
Al Viro
9ea0a46ca2 fix mntput/mntput race
mntput_no_expire() does the calculation of total refcount under mount_lock;
unfortunately, the decrement (as well as all increments) are done outside
of it, leading to false positives in the "are we dropping the last reference"
test.  Consider the following situation:
	* mnt is a lazy-umounted mount, kept alive by two opened files.  One
of those files gets closed.  Total refcount of mnt is 2.  On CPU 42
mntput(mnt) (called from __fput()) drops one reference, decrementing component
	* After it has looked at component #0, the process on CPU 0 does
mntget(), incrementing component #0, gets preempted and gets to run again -
on CPU 69.  There it does mntput(), which drops the reference (component #69)
and proceeds to spin on mount_lock.
	* On CPU 42 our first mntput() finishes counting.  It observes the
decrement of component #69, but not the increment of component #0.  As the
result, the total it gets is not 1 as it should've been - it's 0.  At which
point we decide that vfsmount needs to be killed and proceed to free it and
shut the filesystem down.  However, there's still another opened file
on that filesystem, with reference to (now freed) vfsmount, etc. and we are
screwed.

It's not a wide race, but it can be reproduced with artificial slowdown of
the mnt_get_count() loop, and it should be easier to hit on SMP KVM setups.

Fix consists of moving the refcount decrement under mount_lock; the tricky
part is that we want (and can) keep the fast case (i.e. mount that still
has non-NULL ->mnt_ns) entirely out of mount_lock.  All places that zero
mnt->mnt_ns are dropping some reference to mnt and they call synchronize_rcu()
before that mntput().  IOW, if mntput() observes (under rcu_read_lock())
a non-NULL ->mnt_ns, it is guaranteed that there is another reference yet to
be dropped.

Reported-by: Jann Horn <jannh@google.com>
Tested-by: Jann Horn <jannh@google.com>
Fixes: 48a066e72d ("RCU'd vsfmounts")
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-08-09 17:21:17 -04:00
Daniel Borkmann
9c95420117 Merge branch 'bpf-fix-cpu-and-devmap-teardown'
Jesper Dangaard Brouer says:

====================
Removing entries from cpumap and devmap, goes through a number of
syncronization steps to make sure no new xdp_frames can be enqueued.
But there is a small chance, that xdp_frames remains which have not
been flushed/processed yet.  Flushing these during teardown, happens
from RCU context and not as usual under RX NAPI context.

The optimization introduced in commt 389ab7f01a ("xdp: introduce
xdp_return_frame_rx_napi"), missed that the flush operation can also
be called from RCU context.  Thus, we cannot always use the
xdp_return_frame_rx_napi call, which take advantage of the protection
provided by XDP RX running under NAPI protection.

The samples/bpf xdp_redirect_cpu have a --stress-mode, that is
adjusted to easier reproduce (verified by Red Hat QA).
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-09 21:50:45 +02:00
Jesper Dangaard Brouer
1bf9116d08 xdp: fix bug in devmap teardown code path
Like cpumap teardown, the devmap teardown code also flush remaining
xdp_frames, via bq_xmit_all() in case map entry is removed.  The code
can call xdp_return_frame_rx_napi, from the the wrong context, in-case
ndo_xdp_xmit() fails.

Fixes: 389ab7f01a ("xdp: introduce xdp_return_frame_rx_napi")
Fixes: 735fc4054b ("xdp: change ndo_xdp_xmit API to support bulking")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-09 21:50:44 +02:00
Jesper Dangaard Brouer
37d7ff2595 samples/bpf: xdp_redirect_cpu adjustment to reproduce teardown race easier
The teardown race in cpumap is really hard to reproduce.  These changes
makes it easier to reproduce, for QA.

The --stress-mode now have a case of a very small queue size of 8, that helps
to trigger teardown flush to encounter a full queue, which results in calling
xdp_return_frame API, in a non-NAPI protect context.

Also increase MAX_CPUS, as my QA department have larger machines than me.

Tested-by: Jean-Tsung Hsiao <jhsiao@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-09 21:50:44 +02:00
Jesper Dangaard Brouer
ad0ab027fc xdp: fix bug in cpumap teardown code path
When removing a cpumap entry, a number of syncronization steps happen.
Eventually the teardown code __cpu_map_entry_free is invoked from/via
call_rcu.

The teardown code __cpu_map_entry_free() flushes remaining xdp_frames,
by invoking bq_flush_to_queue, which calls xdp_return_frame_rx_napi().
The issues is that the teardown code is not running in the RX NAPI
code path.  Thus, it is not allowed to invoke the NAPI variant of
xdp_return_frame.

This bug was found and triggered by using the --stress-mode option to
the samples/bpf program xdp_redirect_cpu.  It is hard to trigger,
because the ptr_ring have to be full and cpumap bulk queue max
contains 8 packets, and a remote CPU is racing to empty the ptr_ring
queue.

Fixes: 389ab7f01a ("xdp: introduce xdp_return_frame_rx_napi")
Tested-by: Jean-Tsung Hsiao <jhsiao@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-09 21:50:44 +02:00
Linus Torvalds
112cbae26d Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fix from Herbert Xu:
 "This fixes a performance regression in arm64 NEON crypto as well as a
  crash in x86 aegis/morus on unsupported CPUs"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: x86/aegis,morus - Fix and simplify CPUID checks
  crypto: arm64 - revert NEON yield for fast AEAD implementations
2018-08-09 10:00:15 -07:00
Linus Torvalds
6395ad8559 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) The real fix for the ipv6 route metric leak Sabrina was seeing, from
    Cong Wang.

 2) Fix syzbot triggers AF_PACKET v3 ring buffer insufficient room
    conditions, from Willem de Bruijn.

 3) vsock can reinitialize active work struct, fix from Cong Wang.

 4) RXRPC keepalive generator can wedge a cpu, fix from David Howells.

 5) Fix locking in AF_SMC ioctl, from Ursula Braun.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  dsa: slave: eee: Allow ports to use phylink
  net/smc: move sock lock in smc_ioctl()
  net/smc: allow sysctl rmem and wmem defaults for servers
  net/smc: no shutdown in state SMC_LISTEN
  net: aquantia: Fix IFF_ALLMULTI flag functionality
  rxrpc: Fix the keepalive generator [ver #2]
  net/mlx5e: Cleanup of dcbnl related fields
  net/mlx5e: Properly check if hairpin is possible between two functions
  vhost: reset metadata cache when initializing new IOTLB
  llc: use refcount_inc_not_zero() for llc_sap_find()
  dccp: fix undefined behavior with 'cwnd' shift in ccid2_cwnd_restart()
  tipc: fix an interrupt unsafe locking scenario
  vsock: split dwork to avoid reinitializations
  net: thunderx: check for failed allocation lmac->dmacs
  cxgb4: mk_act_open_req() buggers ->{local, peer}_ip on big-endian hosts
  packet: refine ring v3 block size test to hold one frame
  ip6_tunnel: use the right value for ipv4 min mtu check in ip6_tnl_xmit
  ipv6: fix double refcount of fib6_metrics
2018-08-09 09:57:13 -07:00
George Cherian
5eb173f5c8 i2c: xlp9xx: Fix case where SSIF read transaction completes early
During ipmi stress tests we see occasional failure of transactions
at the boot time. This happens in the case of a I2C_M_RECV_LEN
transactions, when the read transfer completes (with the initial
read length of 34) before the driver gets a chance to handle interrupts.

The current driver code expects at least 2 interrupts for I2C_M_RECV_LEN
transactions. The length is updated during the first interrupt, and  the
buffer contents are only copied during subsequent interrupts. In case of
just one interrupt, we will complete the transaction without copying
out the bytes from RX fifo.

Update the code to drain the RX fifo after the length update,
so that the transaction completes correctly in all cases.

Signed-off-by: George Cherian <george.cherian@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2018-08-09 17:41:13 +02:00
Andrew Lunn
1be52e97ed dsa: slave: eee: Allow ports to use phylink
For a port to be able to use EEE, both the MAC and the PHY must
support EEE. A phy can be provided by both a phydev or phylink. Verify
at least one of these exist, not just phydev.

Fixes: aab9c4067d ("net: dsa: Plug in PHYLINK support")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-08 19:19:03 -07:00
David S. Miller
ef91b6f91a Merge branch 'smc-fixes'
Ursula Braun says:

====================
net/smc: fixes 2018-08-08

here are small fixes for SMC: The first patch makes sure, shutdown code
is not executed for sockets in state SMC_LISTEN. The second patch resets
send and receive buffer values for accepted sockets, since TCP buffer size
optimizations for the internal CLC socket should not be forwarded to the
outer SMC socket. The third patch solves a race between connect and ioctl
reported by syzbot.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-08 19:14:23 -07:00
Ursula Braun
7311d665ca net/smc: move sock lock in smc_ioctl()
When an SMC socket is connecting it is decided whether fallback to
TCP is needed. To avoid races between connect and ioctl move the
sock lock before the use_fallback check.

Reported-by: syzbot+5b2cece1a8ecb2ca77d8@syzkaller.appspotmail.com
Reported-by: syzbot+19557374321ca3710990@syzkaller.appspotmail.com
Fixes: 1992d99882 ("net/smc: take sock lock in smc_ioctl()")
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-08 19:14:22 -07:00
Ursula Braun
bd58c7e086 net/smc: allow sysctl rmem and wmem defaults for servers
Without setsockopt SO_SNDBUF and SO_RCVBUF settings, the sysctl
defaults net.ipv4.tcp_wmem and net.ipv4.tcp_rmem should be the base
for the sizes of the SMC sndbuf and rcvbuf. Any TCP buffer size
optimizations for servers should be ignored.

Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-08 19:14:22 -07:00
Ursula Braun
caa21e19e0 net/smc: no shutdown in state SMC_LISTEN
Invoking shutdown for a socket in state SMC_LISTEN does not make
sense. Nevertheless programs like syzbot fuzzing the kernel may
try to do this. For SMC this means a socket refcounting problem.
This patch makes sure a shutdown call for an SMC socket in state
SMC_LISTEN simply returns with -ENOTCONN.

Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-08 19:14:22 -07:00
Dmitry Bogdanov
11ba961c91 net: aquantia: Fix IFF_ALLMULTI flag functionality
It was noticed that NIC always pass all multicast traffic to the host
regardless of IFF_ALLMULTI flag on the interface.
The rule in MC Filter Table in NIC, that is configured to accept any
multicast packets, is turning on if IFF_MULTICAST flag is set on the
interface. It leads to passing all multicast traffic to the host.
This fix changes the condition to turn on that rule by checking
IFF_ALLMULTI flag as it should.

Fixes: b21f502f84 ("net:ethernet:aquantia: Fix for multicast filter handling.")
Signed-off-by: Dmitry Bogdanov <dmitry.bogdanov@aquantia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-08 19:12:58 -07:00
David Howells
330bdcfadc rxrpc: Fix the keepalive generator [ver #2]
AF_RXRPC has a keepalive message generator that generates a message for a
peer ~20s after the last transmission to that peer to keep firewall ports
open.  The implementation is incorrect in the following ways:

 (1) It mixes up ktime_t and time64_t types.

 (2) It uses ktime_get_real(), the output of which may jump forward or
     backward due to adjustments to the time of day.

 (3) If the current time jumps forward too much or jumps backwards, the
     generator function will crank the base of the time ring round one slot
     at a time (ie. a 1s period) until it catches up, spewing out VERSION
     packets as it goes.

Fix the problem by:

 (1) Only using time64_t.  There's no need for sub-second resolution.

 (2) Use ktime_get_seconds() rather than ktime_get_real() so that time
     isn't perceived to go backwards.

 (3) Simplifying rxrpc_peer_keepalive_worker() by splitting it into two
     parts:

     (a) The "worker" function that manages the buckets and the timer.

     (b) The "dispatch" function that takes the pending peers and
     	 potentially transmits a keepalive packet before putting them back
     	 in the ring into the slot appropriate to the revised last-Tx time.

 (4) Taking everything that's pending out of the ring and splicing it into
     a temporary collector list for processing.

     In the case that there's been a significant jump forward, the ring
     gets entirely emptied and then the time base can be warped forward
     before the peers are processed.

     The warping can't happen if the ring isn't empty because the slot a
     peer is in is keepalive-time dependent, relative to the base time.

 (5) Limit the number of iterations of the bucket array when scanning it.

 (6) Set the timer to skip any empty slots as there's no point waking up if
     there's nothing to do yet.

This can be triggered by an incoming call from a server after a reboot with
AF_RXRPC and AFS built into the kernel causing a peer record to be set up
before userspace is started.  The system clock is then adjusted by
userspace, thereby potentially causing the keepalive generator to have a
meltdown - which leads to a message like:

	watchdog: BUG: soft lockup - CPU#0 stuck for 23s! [kworker/0:1:23]
	...
	Workqueue: krxrpcd rxrpc_peer_keepalive_worker
	EIP: lock_acquire+0x69/0x80
	...
	Call Trace:
	 ? rxrpc_peer_keepalive_worker+0x5e/0x350
	 ? _raw_spin_lock_bh+0x29/0x60
	 ? rxrpc_peer_keepalive_worker+0x5e/0x350
	 ? rxrpc_peer_keepalive_worker+0x5e/0x350
	 ? __lock_acquire+0x3d3/0x870
	 ? process_one_work+0x110/0x340
	 ? process_one_work+0x166/0x340
	 ? process_one_work+0x110/0x340
	 ? worker_thread+0x39/0x3c0
	 ? kthread+0xdb/0x110
	 ? cancel_delayed_work+0x90/0x90
	 ? kthread_stop+0x70/0x70
	 ? ret_from_fork+0x19/0x24

Fixes: ace45bec6d ("rxrpc: Fix firewall route keepalive")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-08 19:10:26 -07:00
David S. Miller
f39cc1c7f3 Merge branch 'mlx5-fixes'
Saeed Mahameed says:

====================
Mellanox, mlx5e fixes 2018-08-07

I know it is late into 4.18 release, and this is why I am submitting
only two mlx5e ethernet fixes.

The first one from Or, is needed for -stable and it fixes hairpin
for "same device" check.

The second fix is a non risk fix from Huy which cleans up and improves
error return value reporting for dcbnl_ieee_setapp.

For -stable v4.16
- net/mlx5e: Properly check if hairpin is possible between two functions
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-08 19:07:38 -07:00
Huy Nguyen
f280c6a1e5 net/mlx5e: Cleanup of dcbnl related fields
Remove unused netdev_registered_init/remove in en.h
Return ENOSUPPORT if the check MLX5_DSCP_SUPPORTED fails.
Remove extra white space

Fixes: 2a5e7a1344 ("net/mlx5e: Add dcbnl dscp to priority support")
Signed-off-by: Huy Nguyen <huyn@mellanox.com>
Cc: Yuval Shaia <yuval.shaia@oracle.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-08 19:07:37 -07:00
Or Gerlitz
816f670623 net/mlx5e: Properly check if hairpin is possible between two functions
The current check relies on function BDF addresses and can get
us wrong e.g when two VFs are assigned into a VM and the PCI
v-address is set by the hypervisor.

Fixes: 5c65c564c9 ('net/mlx5e: Support offloading TC NIC hairpin flows')
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Reported-by: Alaa Hleihel <alaa@mellanox.com>
Tested-by: Alaa Hleihel <alaa@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-08 19:07:37 -07:00
John David Anglin
fedb8da963 parisc: Define mb() and add memory barriers to assembler unlock sequences
For years I thought all parisc machines executed loads and stores in
order. However, Jeff Law recently indicated on gcc-patches that this is
not correct. There are various degrees of out-of-order execution all the
way back to the PA7xxx processor series (hit-under-miss). The PA8xxx
series has full out-of-order execution for both integer operations, and
loads and stores.

This is described in the following article:
http://web.archive.org/web/20040214092531/http://www.cpus.hp.com/technical_references/advperf.shtml

For this reason, we need to define mb() and to insert a memory barrier
before the store unlocking spinlocks. This ensures that all memory
accesses are complete prior to unlocking. The ldcw instruction performs
the same function on entry.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: Helge Deller <deller@gmx.de>
2018-08-08 22:13:32 +02:00