netfilter: x_tables: fix ordering of jumpstack allocation and table update

During kernel stability testing on an SMP ARMv7 system, Yalin Wang
reported the following panic from the netfilter code:

  1fe0: 0000001c 5e2d3b10 4007e779 4009e110 60000010 00000032 ff565656 ff545454
  [<c06c48dc>] (ipt_do_table+0x448/0x584) from [<c0655ef0>] (nf_iterate+0x48/0x7c)
  [<c0655ef0>] (nf_iterate+0x48/0x7c) from [<c0655f7c>] (nf_hook_slow+0x58/0x104)
  [<c0655f7c>] (nf_hook_slow+0x58/0x104) from [<c0683bbc>] (ip_local_deliver+0x88/0xa8)
  [<c0683bbc>] (ip_local_deliver+0x88/0xa8) from [<c0683718>] (ip_rcv_finish+0x418/0x43c)
  [<c0683718>] (ip_rcv_finish+0x418/0x43c) from [<c062b1c4>] (__netif_receive_skb+0x4cc/0x598)
  [<c062b1c4>] (__netif_receive_skb+0x4cc/0x598) from [<c062b314>] (process_backlog+0x84/0x158)
  [<c062b314>] (process_backlog+0x84/0x158) from [<c062de84>] (net_rx_action+0x70/0x1dc)
  [<c062de84>] (net_rx_action+0x70/0x1dc) from [<c0088230>] (__do_softirq+0x11c/0x27c)
  [<c0088230>] (__do_softirq+0x11c/0x27c) from [<c008857c>] (do_softirq+0x44/0x50)
  [<c008857c>] (do_softirq+0x44/0x50) from [<c0088614>] (local_bh_enable_ip+0x8c/0xd0)
  [<c0088614>] (local_bh_enable_ip+0x8c/0xd0) from [<c06b0330>] (inet_stream_connect+0x164/0x298)
  [<c06b0330>] (inet_stream_connect+0x164/0x298) from [<c061d68c>] (sys_connect+0x88/0xc8)
  [<c061d68c>] (sys_connect+0x88/0xc8) from [<c000e340>] (ret_fast_syscall+0x0/0x30)
  Code: 2a000021 e59d2028 e59de01c e59f011c (e7824103)
  ---[ end trace da227214a82491bd ]---
  Kernel panic - not syncing: Fatal exception in interrupt

This comes about because CPU1 is executing xt_replace_table in response
to a setsockopt syscall, resulting in:

	ret = xt_jumpstack_alloc(newinfo);
		--> newinfo->jumpstack = kzalloc(size, GFP_KERNEL);

	[...]

	table->private = newinfo;
	newinfo->initial_entries = private->initial_entries;

Meanwhile, CPU0 is handling the network receive path and ends up in
ipt_do_table, resulting in:

	private = table->private;

	[...]

	jumpstack  = (struct ipt_entry **)private->jumpstack[cpu];

On weakly ordered memory architectures, the writes to table->private
and newinfo->jumpstack from CPU1 can be observed out of order by CPU0.
Furthermore, on architectures which don't respect ordering of address
dependencies (i.e. Alpha), the reads from CPU0 can also be re-ordered.

This patch adds an smp_wmb() before the assignment to table->private
(which is essentially publishing newinfo) to ensure that all writes to
newinfo will be observed before plugging it into the table structure.
A dependent-read barrier is also added on the consumer sides, to ensure
the same ordering requirements are also respected there.

Change-Id: Ia320d52510d7184c0f13d7f130102dbe685e8d6f
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reported-by: Wang, Yalin <Yalin.Wang@sonymobile.com>
Tested-by: Wang, Yalin <Yalin.Wang@sonymobile.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Git-commit: b416c144f46af1a30ddfa4e4319a8f077381ad63
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Osvaldo Banuelos <osvaldob@codeaurora.org>
msm: kgsl: Mark the IOMMU setstate memory as read only

Mark the IOMMU setstate memory as read only in the pagetable.

Change-Id: Ic0dedbadb19e499c749cd744c3e89be3bcb4c2a2
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
[media] v4l2-ioctl.c: handle PREPARE_BUF like QUERYBUF

The core code for PREPARE_BUF didn't take the multiplanar case into
account, which might cause page faults. Handle PREPARE_BUF just like
QUERYBUF and QBUF/DQBUF.

Change-Id: Ida7f712edec32568a8c2651d54b160121009a9c4
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Srinu Gorle <sgorle@codeaurora.org>
CRs-Fixed: 637365
Merge "[media] v4l2-ioctl.c: handle PREPARE_BUF like QUERYBUF"
Merge "netfilter: x_tables: fix ordering of jumpstack allocation and table update"
mdss: mdp3: swap colors when performing csc from yuv2rgb

When ppp hw is performing csc from yuv to rgb there is a color
swap. In order to account for this we need to swap the unpack
and packing order.

Change-Id: I55df9a87300f3ce2c9bf5352725f3ce1d2b1b8a4
Signed-off-by: Terence Hampson <thampson@codeaurora.org>
Merge "mdss: mdp3: swap colors when performing csc from yuv2rgb"
Merge "msm: kgsl: Mark the IOMMU setstate memory as read only"
ARM: dts: msm: Modify bus vector for RNG client on msm8226

Modify the RNG (Random Number Generator) bus vector to use a different
originating master id,this change helps alleviate some slowdowns in boot
time noticed in targets where CPU is artificially bus throttled below a
threshold frequency.

CRs-Fixed: 606371
Change-Id: Ie7ed2bdf863fb4ccb4bc6d5ca7855eb40b959277
Signed-off-by: Sana Venkat Raju <c_vsana@codeaurora.org>
Merge "ARM: dts: msm: Modify bus vector for RNG client on msm8226"
Merge 1d0a28d4554d1b1be6cb125f56fd599a6a3355a9 on remote branch

Change-Id: Idb86d939f4536a45e4ed6dfc1ea95ea9bda55da5
Merge "Merge 1d0a28d4554d1b1be6cb125f56fd599a6a3355a9 on remote branch"