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484,921 commits

Author SHA1 Message Date
Alexey Khoroshilov
a4e9e566be USB: whci-hcd: add check for dma mapping error
[ Upstream commit f9fa1887dc ]

qset_fill_page_list() do not check for dma mapping errors.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-22 12:24:45 -05:00
Alan Stern
782f17fde1 USB: add quirk for devices with broken LPM
[ Upstream commit ad87e03213 ]

Some USB device / host controller combinations seem to have problems
with Link Power Management.  For example, Steinar found that his xHCI
controller wouldn't handle bandwidth calculations correctly for two
video cards simultaneously when LPM was enabled, even though the bus
had plenty of bandwidth available.

This patch introduces a new quirk flag for devices that should remain
disabled for LPM, and creates quirk entries for Steinar's devices.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Steinar H. Gunderson <sgunderson@bigfoot.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-22 12:24:44 -05:00
Konstantin Shkolnyy
5163e2188b USB: cp210x: Remove CP2110 ID from compatibility list
[ Upstream commit 7c90e610b6 ]

CP2110 ID (0x10c4, 0xea80) doesn't belong here because it's a HID
and completely different from CP210x devices.

Signed-off-by: Konstantin Shkolnyy <konstantin.shkolnyy@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-22 12:24:44 -05:00
Jonas Jonsson
fc70c8a467 USB: serial: Another Infineon flash loader USB ID
[ Upstream commit a0e80fbd56 ]

The flash loader has been seen on a Telit UE910 modem. The flash loader
is a bit special, it presents both an ACM and CDC Data interface but
only the latter is useful. Unless a magic string is sent to the device
it will disappear and the regular modem device appears instead.

Signed-off-by: Jonas Jonsson <jonas@ludd.ltu.se>
Tested-by: Daniele Palmas <dnlplm@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-22 12:24:44 -05:00
Jonas Jonsson
753c4e20b6 USB: cdc_acm: Ignore Infineon Flash Loader utility
[ Upstream commit f33a7f72e5 ]

Some modems, such as the Telit UE910, are using an Infineon Flash Loader
utility. It has two interfaces, 2/2/0 (Abstract Modem) and 10/0/0 (CDC
Data). The latter can be used as a serial interface to upgrade the
firmware of the modem. However, that isn't possible when the cdc-acm
driver takes control of the device.

The following is an explanation of the behaviour by Daniele Palmas during
discussion on linux-usb.

"This is what happens when the device is turned on (without modifying
the drivers):

[155492.352031] usb 1-3: new high-speed USB device number 27 using ehci-pci
[155492.485429] usb 1-3: config 1 interface 0 altsetting 0 endpoint 0x81 has an invalid bInterval 255, changing to 11
[155492.485436] usb 1-3: New USB device found, idVendor=058b, idProduct=0041
[155492.485439] usb 1-3: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[155492.485952] cdc_acm 1-3:1.0: ttyACM0: USB ACM device

This is the flashing device that is caught by the cdc-acm driver. Once
the ttyACM appears, the application starts sending a magic string
(simple write on the file descriptor) to keep the device in flashing
mode. If this magic string is not properly received in a certain time
interval, the modem goes on in normal operative mode:

[155493.748094] usb 1-3: USB disconnect, device number 27
[155494.916025] usb 1-3: new high-speed USB device number 28 using ehci-pci
[155495.059978] usb 1-3: New USB device found, idVendor=1bc7, idProduct=0021
[155495.059983] usb 1-3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[155495.059986] usb 1-3: Product: 6 CDC-ACM + 1 CDC-ECM
[155495.059989] usb 1-3: Manufacturer: Telit
[155495.059992] usb 1-3: SerialNumber: 359658044004697
[155495.138958] cdc_acm 1-3:1.0: ttyACM0: USB ACM device
[155495.140832] cdc_acm 1-3:1.2: ttyACM1: USB ACM device
[155495.142827] cdc_acm 1-3:1.4: ttyACM2: USB ACM device
[155495.144462] cdc_acm 1-3:1.6: ttyACM3: USB ACM device
[155495.145967] cdc_acm 1-3:1.8: ttyACM4: USB ACM device
[155495.147588] cdc_acm 1-3:1.10: ttyACM5: USB ACM device
[155495.154322] cdc_ether 1-3:1.12 wwan0: register 'cdc_ether' at usb-0000:00:1a.7-3, Mobile Broadband Network Device, 00:00:11:12:13:14

Using the cdc-acm driver, the string, though being sent in the same way
than using the usb-serial-simple driver (I can confirm that the data is
passing properly since I used an hw usb sniffer), does not make the
device to stay in flashing mode."

Signed-off-by: Jonas Jonsson <jonas@ludd.ltu.se>
Tested-by: Daniele Palmas <dnlplm@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-22 12:24:43 -05:00
Ilya Dryomov
b51cf48b35 rbd: don't leak parent_spec in rbd_dev_probe_parent()
[ Upstream commit 1f2c6651f6 ]

Currently we leak parent_spec and trigger a "parent reference
underflow" warning if rbd_dev_create() in rbd_dev_probe_parent() fails.
The problem is we take the !parent out_err branch and that only drops
refcounts; parent_spec that would've been freed had we called
rbd_dev_unparent() remains and triggers rbd_warn() in
rbd_dev_parent_put() - at that point we have parent_spec != NULL and
parent_ref == 0, so counter ends up being -1 after the decrement.

Redo rbd_dev_probe_parent() to fix this.

Cc: stable@vger.kernel.org # 3.10+, needs backporting for < 4.2
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-22 12:24:43 -05:00
Sasha Levin
e7b7ee7bff RDS: verify the underlying transport exists before creating a connection
[ Upstream commit 74e98eb085 ]

There was no verification that an underlying transport exists when creating
a connection, this would cause dereferencing a NULL ptr.

It might happen on sockets that weren't properly bound before attempting to
send a message, which will cause a NULL ptr deref:

[135546.047719] kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN
[135546.051270] Modules linked in:
[135546.051781] CPU: 4 PID: 15650 Comm: trinity-c4 Not tainted 4.2.0-next-20150902-sasha-00041-gbaa1222-dirty #2527
[135546.053217] task: ffff8800835bc000 ti: ffff8800bc708000 task.ti: ffff8800bc708000
[135546.054291] RIP: __rds_conn_create (net/rds/connection.c:194)
[135546.055666] RSP: 0018:ffff8800bc70fab0  EFLAGS: 00010202
[135546.056457] RAX: dffffc0000000000 RBX: 0000000000000f2c RCX: ffff8800835bc000
[135546.057494] RDX: 0000000000000007 RSI: ffff8800835bccd8 RDI: 0000000000000038
[135546.058530] RBP: ffff8800bc70fb18 R08: 0000000000000001 R09: 0000000000000000
[135546.059556] R10: ffffed014d7a3a23 R11: ffffed014d7a3a21 R12: 0000000000000000
[135546.060614] R13: 0000000000000001 R14: ffff8801ec3d0000 R15: 0000000000000000
[135546.061668] FS:  00007faad4ffb700(0000) GS:ffff880252000000(0000) knlGS:0000000000000000
[135546.062836] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[135546.063682] CR2: 000000000000846a CR3: 000000009d137000 CR4: 00000000000006a0
[135546.064723] Stack:
[135546.065048]  ffffffffafe2055c ffffffffafe23fc1 ffffed00493097bf ffff8801ec3d0008
[135546.066247]  0000000000000000 00000000000000d0 0000000000000000 ac194a24c0586342
[135546.067438]  1ffff100178e1f78 ffff880320581b00 ffff8800bc70fdd0 ffff880320581b00
[135546.068629] Call Trace:
[135546.069028] ? __rds_conn_create (include/linux/rcupdate.h:856 net/rds/connection.c:134)
[135546.069989] ? rds_message_copy_from_user (net/rds/message.c:298)
[135546.071021] rds_conn_create_outgoing (net/rds/connection.c:278)
[135546.071981] rds_sendmsg (net/rds/send.c:1058)
[135546.072858] ? perf_trace_lock (include/trace/events/lock.h:38)
[135546.073744] ? lockdep_init (kernel/locking/lockdep.c:3298)
[135546.074577] ? rds_send_drop_to (net/rds/send.c:976)
[135546.075508] ? __might_fault (./arch/x86/include/asm/current.h:14 mm/memory.c:3795)
[135546.076349] ? __might_fault (mm/memory.c:3795)
[135546.077179] ? rds_send_drop_to (net/rds/send.c:976)
[135546.078114] sock_sendmsg (net/socket.c:611 net/socket.c:620)
[135546.078856] SYSC_sendto (net/socket.c:1657)
[135546.079596] ? SYSC_connect (net/socket.c:1628)
[135546.080510] ? trace_dump_stack (kernel/trace/trace.c:1926)
[135546.081397] ? ring_buffer_unlock_commit (kernel/trace/ring_buffer.c:2479 kernel/trace/ring_buffer.c:2558 kernel/trace/ring_buffer.c:2674)
[135546.082390] ? trace_buffer_unlock_commit (kernel/trace/trace.c:1749)
[135546.083410] ? trace_event_raw_event_sys_enter (include/trace/events/syscalls.h:16)
[135546.084481] ? do_audit_syscall_entry (include/trace/events/syscalls.h:16)
[135546.085438] ? trace_buffer_unlock_commit (kernel/trace/trace.c:1749)
[135546.085515] rds_ib_laddr_check(): addr 36.74.25.172 ret -99 node type -1

Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-22 12:24:42 -05:00
Emmanuel Grumbach
680a741128 iwlwifi: bump firmware API for mvm devices to 12
[ Upstream commit 91f491fd7d ]

This allows 3160 / 7260 / 7265 / 7265D / 8000 devices to
use the latest version of the firmware.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-22 12:24:42 -05:00
Emmanuel Grumbach
2fef208eb5 iwlwifi: 7000: fix reported firmware name for 7265D
[ Upstream commit a443f5e16b ]

We were advertising iwlwifi-7265-X.ucode instead of
iwlwifi-7265D-X.ucode. Fix this.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-22 12:24:41 -05:00
Lu, Han
7f765fcd74 ALSA: hda/hdmi - apply Skylake fix-ups to Broxton display codec
[ Upstream commit e2656412f2 ]

Broxton and Skylake have the same behavior on display audio. So this patch
applys Skylake fix-ups to Broxton.

Signed-off-by: Lu, Han <han.lu@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-22 12:24:41 -05:00
Arnd Bergmann
27327566b1 ceph: fix message length computation
[ Upstream commit 777d738a5e ]

create_request_message() computes the maximum length of a message,
but uses the wrong type for the time stamp: sizeof(struct timespec)
may be 8 or 16 depending on the architecture, while sizeof(struct
ceph_timespec) is always 8, and that is what gets put into the
message.

Found while auditing the uses of timespec for y2038 problems.

Fixes: b8e69066d8 ("ceph: include time stamp in every MDS request")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-21 11:23:29 -05:00
Junxiao Bi
33fde5c22c ocfs2: fix umask ignored issue
[ Upstream commit 8f1eb48758 ]

New created file's mode is not masked with umask, and this makes umask not
work for ocfs2 volume.

Fixes: 702e5bc ("ocfs2: use generic posix ACL infrastructure")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Gang He <ghe@suse.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-21 11:23:29 -05:00
Jeff Layton
2de7d46289 nfs: if we have no valid attrs, then don't declare the attribute cache valid
[ Upstream commit c812012f9c ]

If we pass in an empty nfs_fattr struct to nfs_update_inode, it will
(correctly) not update any of the attributes, but it then clears the
NFS_INO_INVALID_ATTR flag, which indicates that the attributes are
up to date. Don't clear the flag if the fattr struct has no valid
attrs to apply.

Reviewed-by: Steve French <steve.french@primarydata.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-21 11:23:29 -05:00
Benjamin Coddington
d48e82da8b nfs4: start callback_ident at idr 1
[ Upstream commit c68a027c05 ]

If clp->cl_cb_ident is zero, then nfs_cb_idr_remove_locked() skips removing
it when the nfs_client is freed.  A decoding or server bug can then find
and try to put that first nfs_client which would lead to a crash.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Fixes: d687031265 ("nfs4client: convert to idr_alloc()")
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-21 11:23:29 -05:00
Jeff Layton
e46b3f459f nfsd: serialize state seqid morphing operations
[ Upstream commit 35a92fe877 ]

Andrew was seeing a race occur when an OPEN and OPEN_DOWNGRADE were
running in parallel. The server would receive the OPEN_DOWNGRADE first
and check its seqid, but then an OPEN would race in and bump it. The
OPEN_DOWNGRADE would then complete and bump the seqid again.  The result
was that the OPEN_DOWNGRADE would be applied after the OPEN, even though
it should have been rejected since the seqid changed.

The only recourse we have here I think is to serialize operations that
bump the seqid in a stateid, particularly when we're given a seqid in
the call. To address this, we add a new rw_semaphore to the
nfs4_ol_stateid struct. We do a down_write prior to checking the seqid
after looking up the stateid to ensure that nothing else is going to
bump it while we're operating on it.

In the case of OPEN, we do a down_read, as the call doesn't contain a
seqid. Those can run in parallel -- we just need to serialize them when
there is a concurrent OPEN_DOWNGRADE or CLOSE.

LOCK and LOCKU however always take the write lock as there is no
opportunity for parallelizing those.

Reported-and-Tested-by: Andrew W Elble <aweits@rit.edu>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-21 11:23:28 -05:00
Stefan Richter
1d985e6898 firewire: ohci: fix JMicron JMB38x IT context discovery
[ Upstream commit 100ceb66d5 ]

Reported by Clifford and Craig for JMicron OHCI-1394 + SDHCI combo
controllers:  Often or even most of the time, the controller is
initialized with the message "added OHCI v1.10 device as card 0, 4 IR +
0 IT contexts, quirks 0x10".  With 0 isochronous transmit DMA contexts
(IT contexts), applications like audio output are impossible.

However, OHCI-1394 demands that at least 4 IT contexts are implemented
by the link layer controller, and indeed JMicron JMB38x do implement
four of them.  Only their IsoXmitIntMask register is unreliable at early
access.

With my own JMB381 single function controller I found:
  - I can reproduce the problem with a lower probability than Craig's.
  - If I put a loop around the section which clears and reads
    IsoXmitIntMask, then either the first or the second attempt will
    return the correct initial mask of 0x0000000f.  I never encountered
    a case of needing more than a second attempt.
  - Consequently, if I put a dummy reg_read(...IsoXmitIntMaskSet)
    before the first write, the subsequent read will return the correct
    result.
  - If I merely ignore a wrong read result and force the known real
    result, later isochronous transmit DMA usage works just fine.

So let's just fix this chip bug up by the latter method.  Tested with
JMB381 on kernel 3.13 and 4.3.

Since OHCI-1394 generally requires 4 IT contexts at a minium, this
workaround is simply applied whenever the initial read of IsoXmitIntMask
returns 0, regardless whether it's a JMicron chip or not.  I never heard
of this issue together with any other chip though.

I am not 100% sure that this fix works on the OHCI-1394 part of JMB380
and JMB388 combo controllers exactly the same as on the JMB381 single-
function controller, but so far I haven't had a chance to let an owner
of a combo chip run a patched kernel.

Strangely enough, IsoRecvIntMask is always reported correctly, even
though it is probed right before IsoXmitIntMask.

Reported-by: Clifford Dunn
Reported-by: Craig Moore <craig.moore@qenos.com>
Cc: stable@vger.kernel.org
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-21 11:23:28 -05:00
Daeho Jeong
8fecc1e2c4 ext4, jbd2: ensure entering into panic after recording an error in superblock
[ Upstream commit 4327ba52af ]

If a EXT4 filesystem utilizes JBD2 journaling and an error occurs, the
journaling will be aborted first and the error number will be recorded
into JBD2 superblock and, finally, the system will enter into the
panic state in "errors=panic" option.  But, in the rare case, this
sequence is little twisted like the below figure and it will happen
that the system enters into panic state, which means the system reset
in mobile environment, before completion of recording an error in the
journal superblock. In this case, e2fsck cannot recognize that the
filesystem failure occurred in the previous run and the corruption
wouldn't be fixed.

Task A                        Task B
ext4_handle_error()
-> jbd2_journal_abort()
  -> __journal_abort_soft()
    -> __jbd2_journal_abort_hard()
    | -> journal->j_flags |= JBD2_ABORT;
    |
    |                         __ext4_abort()
    |                         -> jbd2_journal_abort()
    |                         | -> __journal_abort_soft()
    |                         |   -> if (journal->j_flags & JBD2_ABORT)
    |                         |           return;
    |                         -> panic()
    |
    -> jbd2_journal_update_sb_errno()

Tested-by: Hobin Woo <hobin.woo@samsung.com>
Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-21 11:23:28 -05:00
Ilya Dryomov
ebf6b53291 rbd: don't put snap_context twice in rbd_queue_workfn()
[ Upstream commit 70b16db86f ]

Commit 4e752f0ab0 ("rbd: access snapshot context and mapping size
safely") moved ceph_get_snap_context() out of rbd_img_request_create()
and into rbd_queue_workfn(), adding a ceph_put_snap_context() to the
error path in rbd_queue_workfn().  However, rbd_img_request_create()
consumes a ref on snapc, so calling ceph_put_snap_context() after
a successful rbd_img_request_create() leads to an extra put.  Fix it.

Cc: stable@vger.kernel.org # 3.18+
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Josh Durgin <jdurgin@redhat.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-21 11:23:28 -05:00
Filipe Manana
c0cdea628d Btrfs: fix race when listing an inode's xattrs
[ Upstream commit f1cd1f0b7d ]

When listing a inode's xattrs we have a time window where we race against
a concurrent operation for adding a new hard link for our inode that makes
us not return any xattr to user space. In order for this to happen, the
first xattr of our inode needs to be at slot 0 of a leaf and the previous
leaf must still have room for an inode ref (or extref) item, and this can
happen because an inode's listxattrs callback does not lock the inode's
i_mutex (nor does the VFS does it for us), but adding a hard link to an
inode makes the VFS lock the inode's i_mutex before calling the inode's
link callback.

If we have the following leafs:

               Leaf X (has N items)                    Leaf Y

 [ ... (257 INODE_ITEM 0) (257 INODE_REF 256) ]  [ (257 XATTR_ITEM 12345), ... ]
           slot N - 2         slot N - 1              slot 0

The race illustrated by the following sequence diagram is possible:

       CPU 1                                               CPU 2

  btrfs_listxattr()

    searches for key (257 XATTR_ITEM 0)

    gets path with path->nodes[0] == leaf X
    and path->slots[0] == N

    because path->slots[0] is >=
    btrfs_header_nritems(leaf X), it calls
    btrfs_next_leaf()

    btrfs_next_leaf()
      releases the path

                                                   adds key (257 INODE_REF 666)
                                                   to the end of leaf X (slot N),
                                                   and leaf X now has N + 1 items

      searches for the key (257 INODE_REF 256),
      with path->keep_locks == 1, because that
      is the last key it saw in leaf X before
      releasing the path

      ends up at leaf X again and it verifies
      that the key (257 INODE_REF 256) is no
      longer the last key in leaf X, so it
      returns with path->nodes[0] == leaf X
      and path->slots[0] == N, pointing to
      the new item with key (257 INODE_REF 666)

    btrfs_listxattr's loop iteration sees that
    the type of the key pointed by the path is
    different from the type BTRFS_XATTR_ITEM_KEY
    and so it breaks the loop and stops looking
    for more xattr items
      --> the application doesn't get any xattr
          listed for our inode

So fix this by breaking the loop only if the key's type is greater than
BTRFS_XATTR_ITEM_KEY and skip the current key if its type is smaller.

Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-21 11:23:27 -05:00
Filipe Manana
938165ad1c Btrfs: fix race leading to BUG_ON when running delalloc for nodatacow
[ Upstream commit 1d512cb77b ]

If we are using the NO_HOLES feature, we have a tiny time window when
running delalloc for a nodatacow inode where we can race with a concurrent
link or xattr add operation leading to a BUG_ON.

This happens because at run_delalloc_nocow() we end up casting a leaf item
of type BTRFS_INODE_[REF|EXTREF]_KEY or of type BTRFS_XATTR_ITEM_KEY to a
file extent item (struct btrfs_file_extent_item) and then analyse its
extent type field, which won't match any of the expected extent types
(values BTRFS_FILE_EXTENT_[REG|PREALLOC|INLINE]) and therefore trigger an
explicit BUG_ON(1).

The following sequence diagram shows how the race happens when running a
no-cow dellaloc range [4K, 8K[ for inode 257 and we have the following
neighbour leafs:

             Leaf X (has N items)                    Leaf Y

 [ ... (257 INODE_ITEM 0) (257 INODE_REF 256) ]  [ (257 EXTENT_DATA 8192), ... ]
              slot N - 2         slot N - 1              slot 0

 (Note the implicit hole for inode 257 regarding the [0, 8K[ range)

       CPU 1                                         CPU 2

 run_dealloc_nocow()
   btrfs_lookup_file_extent()
     --> searches for a key with value
         (257 EXTENT_DATA 4096) in the
         fs/subvol tree
     --> returns us a path with
         path->nodes[0] == leaf X and
         path->slots[0] == N

   because path->slots[0] is >=
   btrfs_header_nritems(leaf X), it
   calls btrfs_next_leaf()

   btrfs_next_leaf()
     --> releases the path

                                              hard link added to our inode,
                                              with key (257 INODE_REF 500)
                                              added to the end of leaf X,
                                              so leaf X now has N + 1 keys

     --> searches for the key
         (257 INODE_REF 256), because
         it was the last key in leaf X
         before it released the path,
         with path->keep_locks set to 1

     --> ends up at leaf X again and
         it verifies that the key
         (257 INODE_REF 256) is no longer
         the last key in the leaf, so it
         returns with path->nodes[0] ==
         leaf X and path->slots[0] == N,
         pointing to the new item with
         key (257 INODE_REF 500)

   the loop iteration of run_dealloc_nocow()
   does not break out the loop and continues
   because the key referenced in the path
   at path->nodes[0] and path->slots[0] is
   for inode 257, its type is < BTRFS_EXTENT_DATA_KEY
   and its offset (500) is less then our delalloc
   range's end (8192)

   the item pointed by the path, an inode reference item,
   is (incorrectly) interpreted as a file extent item and
   we get an invalid extent type, leading to the BUG_ON(1):

   if (extent_type == BTRFS_FILE_EXTENT_REG ||
      extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
       (...)
   } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
       (...)
   } else {
       BUG_ON(1)
   }

The same can happen if a xattr is added concurrently and ends up having
a key with an offset smaller then the delalloc's range end.

So fix this by skipping keys with a type smaller than
BTRFS_EXTENT_DATA_KEY.

Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-21 11:23:27 -05:00
Filipe Manana
c03844aec6 Btrfs: fix race leading to incorrect item deletion when dropping extents
[ Upstream commit aeafbf8486 ]

While running a stress test I got the following warning triggered:

  [191627.672810] ------------[ cut here ]------------
  [191627.673949] WARNING: CPU: 8 PID: 8447 at fs/btrfs/file.c:779 __btrfs_drop_extents+0x391/0xa50 [btrfs]()
  (...)
  [191627.701485] Call Trace:
  [191627.702037]  [<ffffffff8145f077>] dump_stack+0x4f/0x7b
  [191627.702992]  [<ffffffff81095de5>] ? console_unlock+0x356/0x3a2
  [191627.704091]  [<ffffffff8104b3b0>] warn_slowpath_common+0xa1/0xbb
  [191627.705380]  [<ffffffffa0664499>] ? __btrfs_drop_extents+0x391/0xa50 [btrfs]
  [191627.706637]  [<ffffffff8104b46d>] warn_slowpath_null+0x1a/0x1c
  [191627.707789]  [<ffffffffa0664499>] __btrfs_drop_extents+0x391/0xa50 [btrfs]
  [191627.709155]  [<ffffffff8115663c>] ? cache_alloc_debugcheck_after.isra.32+0x171/0x1d0
  [191627.712444]  [<ffffffff81155007>] ? kmemleak_alloc_recursive.constprop.40+0x16/0x18
  [191627.714162]  [<ffffffffa06570c9>] insert_reserved_file_extent.constprop.40+0x83/0x24e [btrfs]
  [191627.715887]  [<ffffffffa065422b>] ? start_transaction+0x3bb/0x610 [btrfs]
  [191627.717287]  [<ffffffffa065b604>] btrfs_finish_ordered_io+0x273/0x4e2 [btrfs]
  [191627.728865]  [<ffffffffa065b888>] finish_ordered_fn+0x15/0x17 [btrfs]
  [191627.730045]  [<ffffffffa067d688>] normal_work_helper+0x14c/0x32c [btrfs]
  [191627.731256]  [<ffffffffa067d96a>] btrfs_endio_write_helper+0x12/0x14 [btrfs]
  [191627.732661]  [<ffffffff81061119>] process_one_work+0x24c/0x4ae
  [191627.733822]  [<ffffffff810615b0>] worker_thread+0x206/0x2c2
  [191627.734857]  [<ffffffff810613aa>] ? process_scheduled_works+0x2f/0x2f
  [191627.736052]  [<ffffffff810613aa>] ? process_scheduled_works+0x2f/0x2f
  [191627.737349]  [<ffffffff810669a6>] kthread+0xef/0xf7
  [191627.738267]  [<ffffffff810f3b3a>] ? time_hardirqs_on+0x15/0x28
  [191627.739330]  [<ffffffff810668b7>] ? __kthread_parkme+0xad/0xad
  [191627.741976]  [<ffffffff81465592>] ret_from_fork+0x42/0x70
  [191627.743080]  [<ffffffff810668b7>] ? __kthread_parkme+0xad/0xad
  [191627.744206] ---[ end trace bbfddacb7aaada8d ]---

  $ cat -n fs/btrfs/file.c
  691  int __btrfs_drop_extents(struct btrfs_trans_handle *trans,
  (...)
  758                  btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
  759                  if (key.objectid > ino ||
  760                      key.type > BTRFS_EXTENT_DATA_KEY || key.offset >= end)
  761                          break;
  762
  763                  fi = btrfs_item_ptr(leaf, path->slots[0],
  764                                      struct btrfs_file_extent_item);
  765                  extent_type = btrfs_file_extent_type(leaf, fi);
  766
  767                  if (extent_type == BTRFS_FILE_EXTENT_REG ||
  768                      extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
  (...)
  774                  } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
  (...)
  778                  } else {
  779                          WARN_ON(1);
  780                          extent_end = search_start;
  781                  }
  (...)

This happened because the item we were processing did not match a file
extent item (its key type != BTRFS_EXTENT_DATA_KEY), and even on this
case we cast the item to a struct btrfs_file_extent_item pointer and
then find a type field value that does not match any of the expected
values (BTRFS_FILE_EXTENT_[REG|PREALLOC|INLINE]). This scenario happens
due to a tiny time window where a race can happen as exemplified below.
For example, consider the following scenario where we're using the
NO_HOLES feature and we have the following two neighbour leafs:

               Leaf X (has N items)                    Leaf Y

[ ... (257 INODE_ITEM 0) (257 INODE_REF 256) ]  [ (257 EXTENT_DATA 8192), ... ]
          slot N - 2         slot N - 1              slot 0

Our inode 257 has an implicit hole in the range [0, 8K[ (implicit rather
than explicit because NO_HOLES is enabled). Now if our inode has an
ordered extent for the range [4K, 8K[ that is finishing, the following
can happen:

          CPU 1                                       CPU 2

  btrfs_finish_ordered_io()
    insert_reserved_file_extent()
      __btrfs_drop_extents()
         Searches for the key
          (257 EXTENT_DATA 4096) through
          btrfs_lookup_file_extent()

         Key not found and we get a path where
         path->nodes[0] == leaf X and
         path->slots[0] == N

         Because path->slots[0] is >=
         btrfs_header_nritems(leaf X), we call
         btrfs_next_leaf()

         btrfs_next_leaf() releases the path

                                                  inserts key
                                                  (257 INODE_REF 4096)
                                                  at the end of leaf X,
                                                  leaf X now has N + 1 keys,
                                                  and the new key is at
                                                  slot N

         btrfs_next_leaf() searches for
         key (257 INODE_REF 256), with
         path->keep_locks set to 1,
         because it was the last key it
         saw in leaf X

           finds it in leaf X again and
           notices it's no longer the last
           key of the leaf, so it returns 0
           with path->nodes[0] == leaf X and
           path->slots[0] == N (which is now
           < btrfs_header_nritems(leaf X)),
           pointing to the new key
           (257 INODE_REF 4096)

         __btrfs_drop_extents() casts the
         item at path->nodes[0], slot
         path->slots[0], to a struct
         btrfs_file_extent_item - it does
         not skip keys for the target
         inode with a type less than
         BTRFS_EXTENT_DATA_KEY
         (BTRFS_INODE_REF_KEY < BTRFS_EXTENT_DATA_KEY)

         sees a bogus value for the type
         field triggering the WARN_ON in
         the trace shown above, and sets
         extent_end = search_start (4096)

         does the if-then-else logic to
         fixup 0 length extent items created
         by a past bug from hole punching:

           if (extent_end == key.offset &&
               extent_end >= search_start)
               goto delete_extent_item;

         that evaluates to true and it ends
         up deleting the key pointed to by
         path->slots[0], (257 INODE_REF 4096),
         from leaf X

The same could happen for example for a xattr that ends up having a key
with an offset value that matches search_start (very unlikely but not
impossible).

So fix this by ensuring that keys smaller than BTRFS_EXTENT_DATA_KEY are
skipped, never casted to struct btrfs_file_extent_item and never deleted
by accident. Also protect against the unexpected case of getting a key
for a lower inode number by skipping that key and issuing a warning.

Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-21 11:23:27 -05:00
Filipe Manana
d7ca88a480 Btrfs: fix file corruption and data loss after cloning inline extents
[ Upstream commit 8039d87d9e ]

Currently the clone ioctl allows to clone an inline extent from one file
to another that already has other (non-inlined) extents. This is a problem
because btrfs is not designed to deal with files having inline and regular
extents, if a file has an inline extent then it must be the only extent
in the file and must start at file offset 0. Having a file with an inline
extent followed by regular extents results in EIO errors when doing reads
or writes against the first 4K of the file.

Also, the clone ioctl allows one to lose data if the source file consists
of a single inline extent, with a size of N bytes, and the destination
file consists of a single inline extent with a size of M bytes, where we
have M > N. In this case the clone operation removes the inline extent
from the destination file and then copies the inline extent from the
source file into the destination file - we lose the M - N bytes from the
destination file, a read operation will get the value 0x00 for any bytes
in the the range [N, M] (the destination inode's i_size remained as M,
that's why we can read past N bytes).

So fix this by not allowing such destructive operations to happen and
return errno EOPNOTSUPP to user space.

Currently the fstest btrfs/035 tests the data loss case but it totally
ignores this - i.e. expects the operation to succeed and does not check
the we got data loss.

The following test case for fstests exercises all these cases that result
in file corruption and data loss:

  seq=`basename $0`
  seqres=$RESULT_DIR/$seq
  echo "QA output created by $seq"
  tmp=/tmp/$$
  status=1	# failure is the default!
  trap "_cleanup; exit \$status" 0 1 2 3 15

  _cleanup()
  {
      rm -f $tmp.*
  }

  # get standard environment, filters and checks
  . ./common/rc
  . ./common/filter

  # real QA test starts here
  _need_to_be_root
  _supported_fs btrfs
  _supported_os Linux
  _require_scratch
  _require_cloner
  _require_btrfs_fs_feature "no_holes"
  _require_btrfs_mkfs_feature "no-holes"

  rm -f $seqres.full

  test_cloning_inline_extents()
  {
      local mkfs_opts=$1
      local mount_opts=$2

      _scratch_mkfs $mkfs_opts >>$seqres.full 2>&1
      _scratch_mount $mount_opts

      # File bar, the source for all the following clone operations, consists
      # of a single inline extent (50 bytes).
      $XFS_IO_PROG -f -c "pwrite -S 0xbb 0 50" $SCRATCH_MNT/bar \
          | _filter_xfs_io

      # Test cloning into a file with an extent (non-inlined) where the
      # destination offset overlaps that extent. It should not be possible to
      # clone the inline extent from file bar into this file.
      $XFS_IO_PROG -f -c "pwrite -S 0xaa 0K 16K" $SCRATCH_MNT/foo \
          | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo

      # Doing IO against any range in the first 4K of the file should work.
      # Due to a past clone ioctl bug which allowed cloning the inline extent,
      # these operations resulted in EIO errors.
      echo "File foo data after clone operation:"
      # All bytes should have the value 0xaa (clone operation failed and did
      # not modify our file).
      od -t x1 $SCRATCH_MNT/foo
      $XFS_IO_PROG -c "pwrite -S 0xcc 0 100" $SCRATCH_MNT/foo | _filter_xfs_io

      # Test cloning the inline extent against a file which has a hole in its
      # first 4K followed by a non-inlined extent. It should not be possible
      # as well to clone the inline extent from file bar into this file.
      $XFS_IO_PROG -f -c "pwrite -S 0xdd 4K 12K" $SCRATCH_MNT/foo2 \
          | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo2

      # Doing IO against any range in the first 4K of the file should work.
      # Due to a past clone ioctl bug which allowed cloning the inline extent,
      # these operations resulted in EIO errors.
      echo "File foo2 data after clone operation:"
      # All bytes should have the value 0x00 (clone operation failed and did
      # not modify our file).
      od -t x1 $SCRATCH_MNT/foo2
      $XFS_IO_PROG -c "pwrite -S 0xee 0 90" $SCRATCH_MNT/foo2 | _filter_xfs_io

      # Test cloning the inline extent against a file which has a size of zero
      # but has a prealloc extent. It should not be possible as well to clone
      # the inline extent from file bar into this file.
      $XFS_IO_PROG -f -c "falloc -k 0 1M" $SCRATCH_MNT/foo3 | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo3

      # Doing IO against any range in the first 4K of the file should work.
      # Due to a past clone ioctl bug which allowed cloning the inline extent,
      # these operations resulted in EIO errors.
      echo "First 50 bytes of foo3 after clone operation:"
      # Should not be able to read any bytes, file has 0 bytes i_size (the
      # clone operation failed and did not modify our file).
      od -t x1 $SCRATCH_MNT/foo3
      $XFS_IO_PROG -c "pwrite -S 0xff 0 90" $SCRATCH_MNT/foo3 | _filter_xfs_io

      # Test cloning the inline extent against a file which consists of a
      # single inline extent that has a size not greater than the size of
      # bar's inline extent (40 < 50).
      # It should be possible to do the extent cloning from bar to this file.
      $XFS_IO_PROG -f -c "pwrite -S 0x01 0 40" $SCRATCH_MNT/foo4 \
          | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo4

      # Doing IO against any range in the first 4K of the file should work.
      echo "File foo4 data after clone operation:"
      # Must match file bar's content.
      od -t x1 $SCRATCH_MNT/foo4
      $XFS_IO_PROG -c "pwrite -S 0x02 0 90" $SCRATCH_MNT/foo4 | _filter_xfs_io

      # Test cloning the inline extent against a file which consists of a
      # single inline extent that has a size greater than the size of bar's
      # inline extent (60 > 50).
      # It should not be possible to clone the inline extent from file bar
      # into this file.
      $XFS_IO_PROG -f -c "pwrite -S 0x03 0 60" $SCRATCH_MNT/foo5 \
          | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo5

      # Reading the file should not fail.
      echo "File foo5 data after clone operation:"
      # Must have a size of 60 bytes, with all bytes having a value of 0x03
      # (the clone operation failed and did not modify our file).
      od -t x1 $SCRATCH_MNT/foo5

      # Test cloning the inline extent against a file which has no extents but
      # has a size greater than bar's inline extent (16K > 50).
      # It should not be possible to clone the inline extent from file bar
      # into this file.
      $XFS_IO_PROG -f -c "truncate 16K" $SCRATCH_MNT/foo6 | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo6

      # Reading the file should not fail.
      echo "File foo6 data after clone operation:"
      # Must have a size of 16K, with all bytes having a value of 0x00 (the
      # clone operation failed and did not modify our file).
      od -t x1 $SCRATCH_MNT/foo6

      # Test cloning the inline extent against a file which has no extents but
      # has a size not greater than bar's inline extent (30 < 50).
      # It should be possible to clone the inline extent from file bar into
      # this file.
      $XFS_IO_PROG -f -c "truncate 30" $SCRATCH_MNT/foo7 | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo7

      # Reading the file should not fail.
      echo "File foo7 data after clone operation:"
      # Must have a size of 50 bytes, with all bytes having a value of 0xbb.
      od -t x1 $SCRATCH_MNT/foo7

      # Test cloning the inline extent against a file which has a size not
      # greater than the size of bar's inline extent (20 < 50) but has
      # a prealloc extent that goes beyond the file's size. It should not be
      # possible to clone the inline extent from bar into this file.
      $XFS_IO_PROG -f -c "falloc -k 0 1M" \
                      -c "pwrite -S 0x88 0 20" \
                      $SCRATCH_MNT/foo8 | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo8

      echo "File foo8 data after clone operation:"
      # Must have a size of 20 bytes, with all bytes having a value of 0x88
      # (the clone operation did not modify our file).
      od -t x1 $SCRATCH_MNT/foo8

      _scratch_unmount
  }

  echo -e "\nTesting without compression and without the no-holes feature...\n"
  test_cloning_inline_extents

  echo -e "\nTesting with compression and without the no-holes feature...\n"
  test_cloning_inline_extents "" "-o compress"

  echo -e "\nTesting without compression and with the no-holes feature...\n"
  test_cloning_inline_extents "-O no-holes" ""

  echo -e "\nTesting with compression and with the no-holes feature...\n"
  test_cloning_inline_extents "-O no-holes" "-o compress"

  status=0
  exit

Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-21 11:23:27 -05:00
Quentin Casasnovas
96c7b10cd8 RDS: fix race condition when sending a message on unbound socket
[ Upstream commit 8c7188b234 ]

Sasha's found a NULL pointer dereference in the RDS connection code when
sending a message to an apparently unbound socket.  The problem is caused
by the code checking if the socket is bound in rds_sendmsg(), which checks
the rs_bound_addr field without taking a lock on the socket.  This opens a
race where rs_bound_addr is temporarily set but where the transport is not
in rds_bind(), leading to a NULL pointer dereference when trying to
dereference 'trans' in __rds_conn_create().

Vegard wrote a reproducer for this issue, so kindly ask him to share if
you're interested.

I cannot reproduce the NULL pointer dereference using Vegard's reproducer
with this patch, whereas I could without.

Complete earlier incomplete fix to CVE-2015-6937:

  74e98eb085 ("RDS: verify the underlying transport exists before creating a connection")

Cc: David S. Miller <davem@davemloft.net>
Cc: stable@vger.kernel.org

Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com>
Reviewed-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-21 11:23:27 -05:00
Rainer Weikusat
7203279803 unix: avoid use-after-free in ep_remove_wait_queue
[ Upstream commit 7d267278a9 ]

Rainer Weikusat <rweikusat@mobileactivedefense.com> writes:
An AF_UNIX datagram socket being the client in an n:1 association with
some server socket is only allowed to send messages to the server if the
receive queue of this socket contains at most sk_max_ack_backlog
datagrams. This implies that prospective writers might be forced to go
to sleep despite none of the message presently enqueued on the server
receive queue were sent by them. In order to ensure that these will be
woken up once space becomes again available, the present unix_dgram_poll
routine does a second sock_poll_wait call with the peer_wait wait queue
of the server socket as queue argument (unix_dgram_recvmsg does a wake
up on this queue after a datagram was received). This is inherently
problematic because the server socket is only guaranteed to remain alive
for as long as the client still holds a reference to it. In case the
connection is dissolved via connect or by the dead peer detection logic
in unix_dgram_sendmsg, the server socket may be freed despite "the
polling mechanism" (in particular, epoll) still has a pointer to the
corresponding peer_wait queue. There's no way to forcibly deregister a
wait queue with epoll.

Based on an idea by Jason Baron, the patch below changes the code such
that a wait_queue_t belonging to the client socket is enqueued on the
peer_wait queue of the server whenever the peer receive queue full
condition is detected by either a sendmsg or a poll. A wake up on the
peer queue is then relayed to the ordinary wait queue of the client
socket via wake function. The connection to the peer wait queue is again
dissolved if either a wake up is about to be relayed or the client
socket reconnects or a dead peer is detected or the client socket is
itself closed. This enables removing the second sock_poll_wait from
unix_dgram_poll, thus avoiding the use-after-free, while still ensuring
that no blocked writer sleeps forever.

Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Fixes: ec0d215f94 ("af_unix: fix 'poll for write'/connected DGRAM sockets")
Reviewed-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 19:20:41 -05:00
Rainer Weikusat
2950f7c837 af_unix: Revert 'lock_interruptible' in stream receive code
[ Upstream commit 3822b5c2fc ]

With b3ca9b02b0, the AF_UNIX SOCK_STREAM
receive code was changed from using mutex_lock(&u->readlock) to
mutex_lock_interruptible(&u->readlock) to prevent signals from being
delayed for an indefinite time if a thread sleeping on the mutex
happened to be selected for handling the signal. But this was never a
problem with the stream receive code (as opposed to its datagram
counterpart) as that never went to sleep waiting for new messages with the
mutex held and thus, wouldn't cause secondary readers to block on the
mutex waiting for the sleeping primary reader. As the interruptible
locking makes the code more complicated in exchange for no benefit,
change it back to using mutex_lock.

Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:52 -05:00
Hannes Frederic Sowa
49d0edfda3 fou: clean up socket with kfree_rcu
[ Upstream commit 3036facbb7 ]

fou->udp_offloads is managed by RCU. As it is actually included inside
the fou sockets, we cannot let the memory go out of scope before a grace
period. We either can synchronize_rcu or switch over to kfree_rcu to
manage the sockets. kfree_rcu seems appropriate as it is used by vxlan
and geneve.

Fixes: 23461551c0 ("fou: Support for foo-over-udp RX path")
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:52 -05:00
David S. Miller
5661985695 bluetooth: Validate socket address length in sco_sock_bind().
[ Upstream commit 5233252fce ]

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:51 -05:00
WANG Cong
652ed6f6ef pptp: verify sockaddr_len in pptp_bind() and pptp_connect()
[ Upstream commit 09ccfd238e ]

Reported-by: Dmitry Vyukov <dvyukov@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:51 -05:00
Vlad Yasevich
eb2c241e08 skbuff: Fix offset error in skb_reorder_vlan_header
[ Upstream commit f654861569 ]

skb_reorder_vlan_header is called after the vlan header has
been pulled.  As a result the offset of the begining of
the mac header has been incrased by 4 bytes (VLAN_HLEN).
When moving the mac addresses, include this incrase in
the offset calcualation so that the mac addresses are
copied correctly.

Fixes: a6e18ff111 (vlan: Fix untag operations of stacked vlans with REORDER_HEADER off)
CC: Nicolas Dichtel <nicolas.dichtel@6wind.com>
CC: Patrick McHardy <kaber@trash.net>
Signed-off-by: Vladislav Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:51 -05:00
Vlad Yasevich
6ff6d3c934 vlan: Fix untag operations of stacked vlans with REORDER_HEADER off
[ Upstream commit a6e18ff111 ]

When we have multiple stacked vlan devices all of which have
turned off REORDER_HEADER flag, the untag operation does not
locate the ethernet addresses correctly for nested vlans.
The reason is that in case of REORDER_HEADER flag being off,
the outer vlan headers are put back and the mac_len is adjusted
to account for the presense of the header.  Then, the subsequent
untag operation, for the next level vlan, always use VLAN_ETH_HLEN
to locate the begining of the ethernet header and that ends up
being a multiple of 4 bytes short of the actuall beginning
of the mac header (the multiple depending on the how many vlan
encapsulations ethere are).

As a reslult, if there are multiple levles of vlan devices
with REODER_HEADER being off, the recevied packets end up
being dropped.

To solve this, we use skb->mac_len as the offset.  The value
is always set on receive path and starts out as a ETH_HLEN.
The value is also updated when the vlan header manupations occur
so we know it will be correct.

Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:51 -05:00
Eric Dumazet
54b6eaa343 net: fix IP early demux races
[ Upstream commit 5037e9ef94 ]

David Wilder reported crashes caused by dst reuse.

<quote David>
  I am seeing a crash on a distro V4.2.3 kernel caused by a double
  release of a dst_entry.  In ipv4_dst_destroy() the call to
  list_empty() finds a poisoned next pointer, indicating the dst_entry
  has already been removed from the list and freed. The crash occurs
  18 to 24 hours into a run of a network stress exerciser.
</quote>

Thanks to his detailed report and analysis, we were able to understand
the core issue.

IP early demux can associate a dst to skb, after a lookup in TCP/UDP
sockets.

When socket cache is not properly set, we want to store into
sk->sk_dst_cache the dst for future IP early demux lookups,
by acquiring a stable refcount on the dst.

Problem is this acquisition is simply using an atomic_inc(),
which works well, unless the dst was queued for destruction from
dst_release() noticing dst refcount went to zero, if DST_NOCACHE
was set on dst.

We need to make sure current refcount is not zero before incrementing
it, or risk double free as David reported.

This patch, being a stable candidate, adds two new helpers, and use
them only from IP early demux problematic paths.

It might be possible to merge in net-next skb_dst_force() and
skb_dst_force_safe(), but I prefer having the smallest patch for stable
kernels : Maybe some skb_dst_force() callers do not expect skb->dst
can suddenly be cleared.

Can probably be backported back to linux-3.6 kernels

Reported-by: David J. Wilder <dwilder@us.ibm.com>
Tested-by: David J. Wilder <dwilder@us.ibm.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:51 -05:00
Sergei Shtylyov
ff9b245372 sh_eth: fix kernel oops in skb_put()
[ Upstream commit 248be83dcb ]

In a low memory situation the following kernel oops occurs:

Unable to handle kernel NULL pointer dereference at virtual address 00000050
pgd = 8490c000
[00000050] *pgd=4651e831, *pte=00000000, *ppte=00000000
Internal error: Oops: 17 [#1] PREEMPT ARM
Modules linked in:
CPU: 0    Not tainted  (3.4-at16 #9)
PC is at skb_put+0x10/0x98
LR is at sh_eth_poll+0x2c8/0xa10
pc : [<8035f780>]    lr : [<8028bf50>]    psr: 60000113
sp : 84eb1a90  ip : 84eb1ac8  fp : 84eb1ac4
r10: 0000003f  r9 : 000005ea  r8 : 00000000
r7 : 00000000  r6 : 940453b0  r5 : 00030000  r4 : 9381b180
r3 : 00000000  r2 : 00000000  r1 : 000005ea  r0 : 00000000
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
Control: 10c53c7d  Table: 4248c059  DAC: 00000015
Process klogd (pid: 2046, stack limit = 0x84eb02e8)
[...]

This is  because netdev_alloc_skb() fails and 'mdp->rx_skbuff[entry]' is left
NULL but sh_eth_rx() later  uses it without checking.  Add such check...

Reported-by: Yasushi SHOJI <yashi@atmark-techno.com>
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:51 -05:00
Hannes Frederic Sowa
e60ccfd9e5 net: add validation for the socket syscall protocol argument
[ Upstream commit 79462ad02e ]

郭永刚 reported that one could simply crash the kernel as root by
using a simple program:

	int socket_fd;
	struct sockaddr_in addr;
	addr.sin_port = 0;
	addr.sin_addr.s_addr = INADDR_ANY;
	addr.sin_family = 10;

	socket_fd = socket(10,3,0x40000000);
	connect(socket_fd , &addr,16);

AF_INET, AF_INET6 sockets actually only support 8-bit protocol
identifiers. inet_sock's skc_protocol field thus is sized accordingly,
thus larger protocol identifiers simply cut off the higher bits and
store a zero in the protocol fields.

This could lead to e.g. NULL function pointer because as a result of
the cut off inet_num is zero and we call down to inet_autobind, which
is NULL for raw sockets.

kernel: Call Trace:
kernel:  [<ffffffff816db90e>] ? inet_autobind+0x2e/0x70
kernel:  [<ffffffff816db9a4>] inet_dgram_connect+0x54/0x80
kernel:  [<ffffffff81645069>] SYSC_connect+0xd9/0x110
kernel:  [<ffffffff810ac51b>] ? ptrace_notify+0x5b/0x80
kernel:  [<ffffffff810236d8>] ? syscall_trace_enter_phase2+0x108/0x200
kernel:  [<ffffffff81645e0e>] SyS_connect+0xe/0x10
kernel:  [<ffffffff81779515>] tracesys_phase2+0x84/0x89

I found no particular commit which introduced this problem.

CVE: CVE-2015-8543
Cc: Cong Wang <cwang@twopensource.com>
Reported-by: 郭永刚 <guoyonggang@360.cn>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:51 -05:00
Eric Dumazet
d6d2547876 ipv6: sctp: clone options to avoid use after free
[ Upstream commit 9470e24f35 ]

SCTP is lacking proper np->opt cloning at accept() time.

TCP and DCCP use ipv6_dup_options() helper, do the same
in SCTP.

We might later factorize this code in a common helper to avoid
future mistakes.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:50 -05:00
Stefan Wahren
d2ed2c315f net: qca_spi: fix transmit queue timeout handling
[ Upstream commit ed7d42e24e ]

In case of a tx queue timeout every transmit is blocked until the
QCA7000 resets himself and triggers a sync which makes the driver
flushs the tx ring. So avoid this blocking situation by triggering
the sync immediately after the timeout. Waking the queue doesn't
make sense in this situation.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Fixes: 291ab06ecf ("net: qualcomm: new Ethernet over SPI driver for QCA7000")
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:50 -05:00
Marcelo Ricardo Leitner
9ee9284e62 sctp: also copy sk_tsflags when copying the socket
[ Upstream commit 50a5ffb1ef ]

As we are keeping timestamps on when copying the socket, we also have to
copy sk_tsflags.

This is needed since b9f40e21ef ("net-timestamp: move timestamp flags
out of sk_flags").

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:50 -05:00
Marcelo Ricardo Leitner
34c664a49b sctp: update the netstamp_needed counter when copying sockets
[ Upstream commit 01ce63c901 ]

Dmitry Vyukov reported that SCTP was triggering a WARN on socket destroy
related to disabling sock timestamp.

When SCTP accepts an association or peel one off, it copies sock flags
but forgot to call net_enable_timestamp() if a packet timestamping flag
was copied, leading to extra calls to net_disable_timestamp() whenever
such clones were closed.

The fix is to call net_enable_timestamp() whenever we copy a sock with
that flag on, like tcp does.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:50 -05:00
Marcelo Ricardo Leitner
348058993d sctp: use the same clock as if sock source timestamps were on
[ Upstream commit cb5e173ed7 ]

SCTP echoes a cookie o INIT ACK chunks that contains a timestamp, for
detecting stale cookies. This cookie is echoed back to the server by the
client and then that timestamp is checked.

Thing is, if the listening socket is using packet timestamping, the
cookie is encoded with ktime_get() value and checked against
ktime_get_real(), as done by __net_timestamp().

The fix is to sctp also use ktime_get_real(), so we can compare bananas
with bananas later no matter if packet timestamping was enabled or not.

Fixes: 52db882f3f ("net: sctp: migrate cookie life from timeval to ktime")
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:50 -05:00
Pavel Machek
0990543936 atl1c: Improve driver not to do order 4 GFP_ATOMIC allocation
[ Upstream commit f2a3771ae8 ]

atl1c driver is doing order-4 allocation with GFP_ATOMIC
priority. That often breaks  networking after resume. Switch to
GFP_KERNEL. Still not ideal, but should be significantly better.

atl1c_setup_ring_resources() is called from .open() function, and
already uses GFP_KERNEL, so this change is safe.

Signed-off-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:50 -05:00
Nicolas Dichtel
67041f12b3 gre6: allow to update all parameters via rtnl
[ Upstream commit 6a61d4dbf4 ]

Parameters were updated only if the kernel was unable to find the tunnel
with the new parameters, ie only if core pamareters were updated (keys,
addr, link, type).
Now it's possible to update ttl, hoplimit, flowinfo and flags.

Fixes: c12b395a46 ("gre: Support GRE over IPv6")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2016-01-15 18:41:50 -05:00
Sasha Levin
60917545df Linux 3.18.25 v3.18.25
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-12-15 12:45:27 -05:00
Eric Dumazet
1ced23539f ipv6: sctp: implement sctp_v6_destroy_sock()
[ Upstream commit 602dd62dfb ]

Dmitry Vyukov reported a memory leak using IPV6 SCTP sockets.

We need to call inet6_destroy_sock() to properly release
inet6 specific fields.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-12-14 12:19:27 -05:00
Konstantin Khlebnikov
18c103ad86 net/neighbour: fix crash at dumping device-agnostic proxy entries
[ Upstream commit 6adc5fd6a1 ]

Proxy entries could have null pointer to net-device.

Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Fixes: 84920c1420 ("net: Allow ipv6 proxies and arp proxies be shown with iproute2")
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-12-14 12:19:27 -05:00
Eric Dumazet
46ddb98e20 ipv6: add complete rcu protection around np->opt
[ Upstream commit 45f6fad84c ]

This patch addresses multiple problems :

UDP/RAW sendmsg() need to get a stable struct ipv6_txoptions
while socket is not locked : Other threads can change np->opt
concurrently. Dmitry posted a syzkaller
(http://github.com/google/syzkaller) program desmonstrating
use-after-free.

Starting with TCP/DCCP lockless listeners, tcp_v6_syn_recv_sock()
and dccp_v6_request_recv_sock() also need to use RCU protection
to dereference np->opt once (before calling ipv6_dup_options())

This patch adds full RCU protection to np->opt

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-12-14 12:19:26 -05:00
Michal Kubeček
e33c9be772 ipv6: distinguish frag queues by device for multicast and link-local packets
[ Upstream commit 264640fc2c ]

If a fragmented multicast packet is received on an ethernet device which
has an active macvlan on top of it, each fragment is duplicated and
received both on the underlying device and the macvlan. If some
fragments for macvlan are processed before the whole packet for the
underlying device is reassembled, the "overlapping fragments" test in
ip6_frag_queue() discards the whole fragment queue.

To resolve this, add device ifindex to the search key and require it to
match reassembling multicast packets and packets to link-local
addresses.

Note: similar patch has been already submitted by Yoshifuji Hideaki in

  http://patchwork.ozlabs.org/patch/220979/

but got lost and forgotten for some reason.

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-12-14 12:19:26 -05:00
Aaro Koskinen
fbf44baf44 broadcom: fix PHY_ID_BCM5481 entry in the id table
[ Upstream commit 3c25a860d1 ]

Commit fcb26ec5b1 ("broadcom: move all PHY_ID's to header")
updated broadcom_tbl to use PHY_IDs, but incorrectly replaced 0x0143bca0
with PHY_ID_BCM5482 (making a duplicate entry, and completely omitting
the original). Fix that.

Fixes: fcb26ec5b1 ("broadcom: move all PHY_ID's to header")
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-12-14 12:19:26 -05:00
Nikolay Aleksandrov
357dc4e63e net: ip6mr: fix static mfc/dev leaks on table destruction
[ Upstream commit 4c6980462f ]

Similar to ipv4, when destroying an mrt table the static mfc entries and
the static devices are kept, which leads to devices that can never be
destroyed (because of refcnt taken) and leaked memory. Make sure that
everything is cleaned up on netns destruction.

Fixes: 8229efdaef ("netns: ip6mr: enable namespace support in ipv6 multicast forwarding code")
CC: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Reviewed-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-12-14 12:19:25 -05:00
Nikolay Aleksandrov
691e3dcb40 net: ipmr: fix static mfc/dev leaks on table destruction
[ Upstream commit 0e615e9601 ]

When destroying an mrt table the static mfc entries and the static
devices are kept, which leads to devices that can never be destroyed
(because of refcnt taken) and leaked memory, for example:
unreferenced object 0xffff880034c144c0 (size 192):
  comm "mfc-broken", pid 4777, jiffies 4320349055 (age 46001.964s)
  hex dump (first 32 bytes):
    98 53 f0 34 00 88 ff ff 98 53 f0 34 00 88 ff ff  .S.4.....S.4....
    ef 0a 0a 14 01 02 03 04 00 00 00 00 01 00 00 00  ................
  backtrace:
    [<ffffffff815c1b9e>] kmemleak_alloc+0x4e/0xb0
    [<ffffffff811ea6e0>] kmem_cache_alloc+0x190/0x300
    [<ffffffff815931cb>] ip_mroute_setsockopt+0x5cb/0x910
    [<ffffffff8153d575>] do_ip_setsockopt.isra.11+0x105/0xff0
    [<ffffffff8153e490>] ip_setsockopt+0x30/0xa0
    [<ffffffff81564e13>] raw_setsockopt+0x33/0x90
    [<ffffffff814d1e14>] sock_common_setsockopt+0x14/0x20
    [<ffffffff814d0b51>] SyS_setsockopt+0x71/0xc0
    [<ffffffff815cdbf6>] entry_SYSCALL_64_fastpath+0x16/0x7a
    [<ffffffffffffffff>] 0xffffffffffffffff

Make sure that everything is cleaned on netns destruction.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Reviewed-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-12-14 12:19:25 -05:00
Daniel Borkmann
306c535778 net, scm: fix PaX detected msg_controllen overflow in scm_detach_fds
[ Upstream commit 6900317f5e ]

David and HacKurx reported a following/similar size overflow triggered
in a grsecurity kernel, thanks to PaX's gcc size overflow plugin:

(Already fixed in later grsecurity versions by Brad and PaX Team.)

[ 1002.296137] PAX: size overflow detected in function scm_detach_fds net/core/scm.c:314
               cicus.202_127 min, count: 4, decl: msg_controllen; num: 0; context: msghdr;
[ 1002.296145] CPU: 0 PID: 3685 Comm: scm_rights_recv Not tainted 4.2.3-grsec+ #7
[ 1002.296149] Hardware name: Apple Inc. MacBookAir5,1/Mac-66F35F19FE2A0D05, [...]
[ 1002.296153]  ffffffff81c27366 0000000000000000 ffffffff81c27375 ffffc90007843aa8
[ 1002.296162]  ffffffff818129ba 0000000000000000 ffffffff81c27366 ffffc90007843ad8
[ 1002.296169]  ffffffff8121f838 fffffffffffffffc fffffffffffffffc ffffc90007843e60
[ 1002.296176] Call Trace:
[ 1002.296190]  [<ffffffff818129ba>] dump_stack+0x45/0x57
[ 1002.296200]  [<ffffffff8121f838>] report_size_overflow+0x38/0x60
[ 1002.296209]  [<ffffffff816a979e>] scm_detach_fds+0x2ce/0x300
[ 1002.296220]  [<ffffffff81791899>] unix_stream_read_generic+0x609/0x930
[ 1002.296228]  [<ffffffff81791c9f>] unix_stream_recvmsg+0x4f/0x60
[ 1002.296236]  [<ffffffff8178dc00>] ? unix_set_peek_off+0x50/0x50
[ 1002.296243]  [<ffffffff8168fac7>] sock_recvmsg+0x47/0x60
[ 1002.296248]  [<ffffffff81691522>] ___sys_recvmsg+0xe2/0x1e0
[ 1002.296257]  [<ffffffff81693496>] __sys_recvmsg+0x46/0x80
[ 1002.296263]  [<ffffffff816934fc>] SyS_recvmsg+0x2c/0x40
[ 1002.296271]  [<ffffffff8181a3ab>] entry_SYSCALL_64_fastpath+0x12/0x85

Further investigation showed that this can happen when an *odd* number of
fds are being passed over AF_UNIX sockets.

In these cases CMSG_LEN(i * sizeof(int)) and CMSG_SPACE(i * sizeof(int)),
where i is the number of successfully passed fds, differ by 4 bytes due
to the extra CMSG_ALIGN() padding in CMSG_SPACE() to an 8 byte boundary
on 64 bit. The padding is used to align subsequent cmsg headers in the
control buffer.

When the control buffer passed in from the receiver side *lacks* these 4
bytes (e.g. due to buggy/wrong API usage), then msg->msg_controllen will
overflow in scm_detach_fds():

  int cmlen = CMSG_LEN(i * sizeof(int));  <--- cmlen w/o tail-padding
  err = put_user(SOL_SOCKET, &cm->cmsg_level);
  if (!err)
    err = put_user(SCM_RIGHTS, &cm->cmsg_type);
  if (!err)
    err = put_user(cmlen, &cm->cmsg_len);
  if (!err) {
    cmlen = CMSG_SPACE(i * sizeof(int));  <--- cmlen w/ 4 byte extra tail-padding
    msg->msg_control += cmlen;
    msg->msg_controllen -= cmlen;         <--- iff no tail-padding space here ...
  }                                            ... wrap-around

F.e. it will wrap to a length of 18446744073709551612 bytes in case the
receiver passed in msg->msg_controllen of 20 bytes, and the sender
properly transferred 1 fd to the receiver, so that its CMSG_LEN results
in 20 bytes and CMSG_SPACE in 24 bytes.

In case of MSG_CMSG_COMPAT (scm_detach_fds_compat()), I haven't seen an
issue in my tests as alignment seems always on 4 byte boundary. Same
should be in case of native 32 bit, where we end up with 4 byte boundaries
as well.

In practice, passing msg->msg_controllen of 20 to recvmsg() while receiving
a single fd would mean that on successful return, msg->msg_controllen is
being set by the kernel to 24 bytes instead, thus more than the input
buffer advertised. It could f.e. become an issue if such application later
on zeroes or copies the control buffer based on the returned msg->msg_controllen
elsewhere.

Maximum number of fds we can send is a hard upper limit SCM_MAX_FD (253).

Going over the code, it seems like msg->msg_controllen is not being read
after scm_detach_fds() in scm_recv() anymore by the kernel, good!

Relevant recvmsg() handler are unix_dgram_recvmsg() (unix_seqpacket_recvmsg())
and unix_stream_recvmsg(). Both return back to their recvmsg() caller,
and ___sys_recvmsg() places the updated length, that is, new msg_control -
old msg_control pointer into msg->msg_controllen (hence the 24 bytes seen
in the example).

Long time ago, Wei Yongjun fixed something related in commit 1ac70e7ad2
("[NET]: Fix function put_cmsg() which may cause usr application memory
overflow").

RFC3542, section 20.2. says:

  The fields shown as "XX" are possible padding, between the cmsghdr
  structure and the data, and between the data and the next cmsghdr
  structure, if required by the implementation. While sending an
  application may or may not include padding at the end of last
  ancillary data in msg_controllen and implementations must accept both
  as valid. On receiving a portable application must provide space for
  padding at the end of the last ancillary data as implementations may
  copy out the padding at the end of the control message buffer and
  include it in the received msg_controllen. When recvmsg() is called
  if msg_controllen is too small for all the ancillary data items
  including any trailing padding after the last item an implementation
  may set MSG_CTRUNC.

Since we didn't place MSG_CTRUNC for already quite a long time, just do
the same as in 1ac70e7ad2 to avoid an overflow.

Btw, even man-page author got this wrong :/ See db939c9b26e9 ("cmsg.3: Fix
error in SCM_RIGHTS code sample"). Some people must have copied this (?),
thus it got triggered in the wild (reported several times during boot by
David and HacKurx).

No Fixes tag this time as pre 2002 (that is, pre history tree).

Reported-by: David Sterba <dave@jikos.cz>
Reported-by: HacKurx <hackurx@gmail.com>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: Eric Dumazet <edumazet@google.com>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-12-14 12:19:25 -05:00
Eric Dumazet
7d76c6f791 tcp: initialize tp->copied_seq in case of cross SYN connection
[ Upstream commit 142a2e7ece ]

Dmitry provided a syzkaller (http://github.com/google/syzkaller)
generated program that triggers the WARNING at
net/ipv4/tcp.c:1729 in tcp_recvmsg() :

WARN_ON(tp->copied_seq != tp->rcv_nxt &&
        !(flags & (MSG_PEEK | MSG_TRUNC)));

His program is specifically attempting a Cross SYN TCP exchange,
that we support (for the pleasure of hackers ?), but it looks we
lack proper tcp->copied_seq initialization.

Thanks again Dmitry for your report and testings.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
2015-12-14 12:19:25 -05:00