->readdir passes lofft_t offsets (used as nfs cookies) to
nfs3svc_encode_entry{,_plus}, but when they pass it on to encode_entry it
becomes an 'off_t', which isn't good.

So filesystems that returned 64bit offsets would lose.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Adrian Bunk <bunk@kernel.org>

unlock_buffer(), like unlock_page(), must not clear the lock without
ensuring that the critical section is closed.

Mingming later sent the same patch, saying:

We are running SDET benchmark and saw double free issue for ext3 extended
attributes block, which complains the same xattr block already being freed (in
ext3_xattr_release_block()).  The problem could also been triggered by
multiple threads loop untar/rm a kernel tree.

The race is caused by missing a memory barrier at unlock_buffer() before the
lock bit being cleared, resulting in possible concurrent h_refcounter update.
That causes a reference counter leak, then later leads to the double free that
we have seen.

Inside unlock_buffer(), there is a memory barrier is placed *after* the lock
bit is being cleared, however, there is no memory barrier *before* the bit is
cleared.  On some arch the h_refcount update instruction and the clear bit
instruction could be reordered, thus leave the critical section re-entered.

The race is like this: For example, if the h_refcount is initialized as 1,

cpu 0:                                   cpu1
--------------------------------------   -----------------------------------
lock_buffer() /* test_and_set_bit */
clear_buffer_locked(bh);
                                        lock_buffer() /* test_and_set_bit */
h_refcount = h_refcount+1; /* = 2*/     h_refcount = h_refcount + 1; /*= 2 */
                                        clear_buffer_locked(bh);
....                                    ......

We lost a h_refcount here.  We need a memory barrier before the buffer head
lock bit being cleared to force the order of the two writes.  Please apply.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Adrian Bunk <bunk@kernel.org>

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Adrian Bunk <bunk@kernel.org>

It didn't handle that case at all, and now dump_stack()
can be implemented directly as show_stack(current, NULL)

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Adrian Bunk <bunk@kernel.org>

The snap_rcv code reads 5 bytes so we should make sure that
we have 5 bytes in the head before proceeding.

Based on diagnosis and fix by Evgeniy Polyakov, reported by
Alan J. Wylie.

Patch also kills the skb->sk assignment before kfree_skb
since it's redundant.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Adrian Bunk <bunk@kernel.org>

-Fixes ABBA deadlock noted by Patrick McHardy <kaber@trash.net>:

> There is at least one ABBA deadlock, est_timer() does:
> read_lock(&est_lock)
> spin_lock(e->stats_lock) (which is dev->queue_lock)
>
> and qdisc_destroy calls htb_destroy under dev->queue_lock, which
> calls htb_destroy_class, then gen_kill_estimator and this
> write_locks est_lock.

To fix the ABBA deadlock the rate estimators are now kept on an rcu list.

-The est_lock changes the use from protecting the list to protecting
the update to the 'bstat' pointer in order to avoid NULL dereferencing.

-The 'interval' member of the gen_estimator structure removed as it is
not needed.

Signed-off-by: Ranko Zivojnovic <ranko@spidernet.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Adrian Bunk <bunk@kernel.org>

Currently when icmp_errors_use_inbound_ifaddr is set and an ICMP error is
sent after the packet passed through ip_output(), an address from the
outgoing interface is chosen as ICMP source address since skb->dev doesn't
point to the incoming interface anymore.

Fix this by doing an interface lookup on rt->dst.iif and using that device.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Adrian Bunk <bunk@kernel.org>

Normally a serial Bluetooth device is opened, TIOSETD'ed to N_HCI line
discipline, HCIUARTSETPROTO'ed and finally closed. In case the device
fails to HCIUARTSETPROTO, closing it produces a NULL pointer dereference.

Signed-off-by: Ohad Ben-Cohen <ohad@bencohen.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Adrian Bunk <bunk@kernel.org>