Граф коммитов

23464 Коммитов

Автор SHA1 Сообщение Дата
Daniel Mack 01ae87eab5 bpf: cgroup: fix documentation of __cgroup_bpf_update()
There's a 'not' missing in one paragraph. Add it.

Fixes: 3007098494 ("cgroup: add support for eBPF programs")
Signed-off-by: Daniel Mack <daniel@zonque.org>
Reported-by: Rami Rosen <roszenrami@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-29 19:50:59 -05:00
Daniel Borkmann a3af5f8001 bpf: allow for mount options to specify permissions
Since we recently converted the BPF filesystem over to use mount_nodev(),
we now have the possibility to also hold mount options in sb's s_fs_info.
This work implements mount options support for specifying permissions on
the sb's inode, which will be used by tc when it manually needs to mount
the fs.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-27 20:38:47 -05:00
Daniel Borkmann 21116b7068 bpf: add owner_prog_type and accounted mem to array map's fdinfo
Allow for checking the owner_prog_type of a program array map. In some
cases bpf(2) can return -EINVAL /after/ the verifier passed and did all
the rewrites of the bpf program.

The reason that lets us fail at this late stage is that program array
maps are incompatible. Allow users to inspect this earlier after they
got the map fd through BPF_OBJ_GET command. tc will get support for this.

Also, display how much we charged the map with regards to RLIMIT_MEMLOCK.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-27 20:38:47 -05:00
Daniel Borkmann 88575199cc bpf: drop unnecessary context cast from BPF_PROG_RUN
Since long already bpf_func is not only about struct sk_buff * as
input anymore. Make it generic as void *, so that callers don't
need to cast for it each time they call BPF_PROG_RUN().

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-27 20:38:47 -05:00
David S. Miller 0b42f25d2f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
udplite conflict is resolved by taking what 'net-next' did
which removed the backlog receive method assignment, since
it is no longer necessary.

Two entries were added to the non-priv ethtool operations
switch statement, one in 'net' and one in 'net-next, so
simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-26 23:42:21 -05:00
Daniel Mack f432455148 bpf: add BPF_PROG_ATTACH and BPF_PROG_DETACH commands
Extend the bpf(2) syscall by two new commands, BPF_PROG_ATTACH and
BPF_PROG_DETACH which allow attaching and detaching eBPF programs
to a target.

On the API level, the target could be anything that has an fd in
userspace, hence the name of the field in union bpf_attr is called
'target_fd'.

When called with BPF_ATTACH_TYPE_CGROUP_INET_{E,IN}GRESS, the target is
expected to be a valid file descriptor of a cgroup v2 directory which
has the bpf controller enabled. These are the only use-cases
implemented by this patch at this point, but more can be added.

If a program of the given type already exists in the given cgroup,
the program is swapped automically, so userspace does not have to drop
an existing program first before installing a new one, which would
otherwise leave a gap in which no program is attached.

For more information on the propagation logic to subcgroups, please
refer to the bpf cgroup controller implementation.

The API is guarded by CAP_NET_ADMIN.

Signed-off-by: Daniel Mack <daniel@zonque.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-25 16:26:04 -05:00
Daniel Mack 3007098494 cgroup: add support for eBPF programs
This patch adds two sets of eBPF program pointers to struct cgroup.
One for such that are directly pinned to a cgroup, and one for such
that are effective for it.

To illustrate the logic behind that, assume the following example
cgroup hierarchy.

  A - B - C
        \ D - E

If only B has a program attached, it will be effective for B, C, D
and E. If D then attaches a program itself, that will be effective for
both D and E, and the program in B will only affect B and C. Only one
program of a given type is effective for a cgroup.

Attaching and detaching programs will be done through the bpf(2)
syscall. For now, ingress and egress inet socket filtering are the
only supported use-cases.

Signed-off-by: Daniel Mack <daniel@zonque.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-25 16:25:52 -05:00
Linus Torvalds ded9b5dd20 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Six fixes for bugs that were found via fuzzing, and a trivial
  hw-enablement patch for AMD Family-17h CPU PMUs"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/uncore: Allow only a single PMU/box within an events group
  perf/x86/intel: Cure bogus unwind from PEBS entries
  perf/x86: Restore TASK_SIZE check on frame pointer
  perf/core: Fix address filter parser
  perf/x86: Add perf support for AMD family-17h processors
  perf/x86/uncore: Fix crash by removing bogus event_list[] handling for SNB client uncore IMC
  perf/core: Do not set cpuctx->cgrp for unscheduled cgroups
2016-11-23 08:09:21 -08:00
David S. Miller f9aa9dc7d2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
All conflicts were simple overlapping changes except perhaps
for the Thunder driver.

That driver has a change_mtu method explicitly for sending
a message to the hardware.  If that fails it returns an
error.

Normally a driver doesn't need an ndo_change_mtu method becuase those
are usually just range changes, which are now handled generically.
But since this extra operation is needed in the Thunder driver, it has
to stay.

However, if the message send fails we have to restore the original
MTU before the change because the entire call chain expects that if
an error is thrown by ndo_change_mtu then the MTU did not change.
Therefore code is added to nicvf_change_mtu to remember the original
MTU, and to restore it upon nicvf_update_hw_max_frs() failue.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-22 13:27:16 -05:00
Oleg Nesterov 8e5bfa8c1f sched/autogroup: Do not use autogroup->tg in zombie threads
Exactly because for_each_thread() in autogroup_move_group() can't see it
and update its ->sched_task_group before _put() and possibly free().

So the exiting task needs another sched_move_task() before exit_notify()
and we need to re-introduce the PF_EXITING (or similar) check removed by
the previous change for another reason.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hartsjc@redhat.com
Cc: vbendel@redhat.com
Cc: vlovejoy@redhat.com
Link: http://lkml.kernel.org/r/20161114184612.GA15968@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-22 12:33:43 +01:00
Oleg Nesterov 18f649ef34 sched/autogroup: Fix autogroup_move_group() to never skip sched_move_task()
The PF_EXITING check in task_wants_autogroup() is no longer needed. Remove
it, but see the next patch.

However the comment is correct in that autogroup_move_group() must always
change task_group() for every thread so the sysctl_ check is very wrong;
we can race with cgroups and even sys_setsid() is not safe because a task
running with task_group() == ag->tg must participate in refcounting:

	int main(void)
	{
		int sctl = open("/proc/sys/kernel/sched_autogroup_enabled", O_WRONLY);

		assert(sctl > 0);
		if (fork()) {
			wait(NULL); // destroy the child's ag/tg
			pause();
		}

		assert(pwrite(sctl, "1\n", 2, 0) == 2);
		assert(setsid() > 0);
		if (fork())
			pause();

		kill(getppid(), SIGKILL);
		sleep(1);

		// The child has gone, the grandchild runs with kref == 1
		assert(pwrite(sctl, "0\n", 2, 0) == 2);
		assert(setsid() > 0);

		// runs with the freed ag/tg
		for (;;)
			sleep(1);

		return 0;
	}

crashes the kernel. It doesn't really need sleep(1), it doesn't matter if
autogroup_move_group() actually frees the task_group or this happens later.

Reported-by: Vern Lovejoy <vlovejoy@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hartsjc@redhat.com
Cc: vbendel@redhat.com
Link: http://lkml.kernel.org/r/20161114184609.GA15965@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-22 12:33:42 +01:00
Linus Torvalds 8d1a2408ef Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc fixes from David Miller:

 1) With modern networking cards we can run out of 32-bit DMA space, so
    support 64-bit DMA addressing when possible on sparc64. From Dave
    Tushar.

 2) Some signal frame validation checks are inverted on sparc32, fix
    from Andreas Larsson.

 3) Lockdep tables can get too large in some circumstances on sparc64,
    add a way to adjust the size a bit. From Babu Moger.

 4) Fix NUMA node probing on some sun4v systems, from Thomas Tai.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: drop duplicate header scatterlist.h
  lockdep: Limit static allocations if PROVE_LOCKING_SMALL is defined
  config: Adding the new config parameter CONFIG_PROVE_LOCKING_SMALL for sparc
  sunbmac: Fix compiler warning
  sunqe: Fix compiler warnings
  sparc64: Enable 64-bit DMA
  sparc64: Enable sun4v dma ops to use IOMMU v2 APIs
  sparc64: Bind PCIe devices to use IOMMU v2 service
  sparc64: Initialize iommu_map_table and iommu_pool
  sparc64: Add ATU (new IOMMU) support
  sparc64: Add FORCE_MAX_ZONEORDER and default to 13
  sparc64: fix compile warning section mismatch in find_node()
  sparc32: Fix inverted invalid_frame_pointer checks on sigreturns
  sparc64: Fix find_node warning if numa node cannot be found
2016-11-21 13:56:17 -08:00
Linus Torvalds 27e7ab99db Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Clear congestion control state when changing algorithms on an
    existing socket, from Florian Westphal.

 2) Fix register bit values in altr_tse_pcs portion of stmmac driver,
    from Jia Jie Ho.

 3) Fix PTP handling in stammc driver for GMAC4, from Giuseppe
    CAVALLARO.

 4) Fix udplite multicast delivery handling, it ignores the udp_table
    parameter passed into the lookups, from Pablo Neira Ayuso.

 5) Synchronize the space estimated by rtnl_vfinfo_size and the space
    actually used by rtnl_fill_vfinfo. From Sabrina Dubroca.

 6) Fix memory leak in fib_info when splitting nodes, from Alexander
    Duyck.

 7) If a driver does a napi_hash_del() explicitily and not via
    netif_napi_del(), it must perform RCU synchronization as needed. Fix
    this in virtio-net and bnxt drivers, from Eric Dumazet.

 8) Likewise, it is not necessary to invoke napi_hash_del() is we are
    also doing neif_napi_del() in the same code path. Remove such calls
    from be2net and cxgb4 drivers, also from Eric Dumazet.

 9) Don't allocate an ID in peernet2id_alloc() if the netns is dead,
    from WANG Cong.

10) Fix OF node and device struct leaks in of_mdio, from Johan Hovold.

11) We cannot cache routes in ip6_tunnel when using inherited traffic
    classes, from Paolo Abeni.

12) Fix several crashes and leaks in cpsw driver, from Johan Hovold.

13) Splice operations cannot use freezable blocking calls in AF_UNIX,
    from WANG Cong.

14) Link dump filtering by master device and kind support added an error
    in loop index updates during the dump if we actually do filter, fix
    from Zhang Shengju.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (59 commits)
  tcp: zero ca_priv area when switching cc algorithms
  net: l2tp: Treat NET_XMIT_CN as success in l2tp_eth_dev_xmit
  ethernet: stmmac: make DWMAC_STM32 depend on it's associated SoC
  tipc: eliminate obsolete socket locking policy description
  rtnl: fix the loop index update error in rtnl_dump_ifinfo()
  l2tp: fix racy SOCK_ZAPPED flag check in l2tp_ip{,6}_bind()
  net: macb: add check for dma mapping error in start_xmit()
  rtnetlink: fix FDB size computation
  netns: fix get_net_ns_by_fd(int pid) typo
  af_unix: conditionally use freezable blocking calls in read
  net: ethernet: ti: cpsw: fix fixed-link phy probe deferral
  net: ethernet: ti: cpsw: add missing sanity check
  net: ethernet: ti: cpsw: fix secondary-emac probe error path
  net: ethernet: ti: cpsw: fix of_node and phydev leaks
  net: ethernet: ti: cpsw: fix deferred probe
  net: ethernet: ti: cpsw: fix mdio device reference leak
  net: ethernet: ti: cpsw: fix bad register access in probe error path
  net: sky2: Fix shutdown crash
  cfg80211: limit scan results cache size
  net sched filters: pass netlink message flags in event notification
  ...
2016-11-21 13:26:28 -08:00
Daniel Borkmann 97bc402db7 bpf, mlx5: fix mlx5e_create_rq taking reference on prog
In mlx5e_create_rq(), when creating a new queue, we call bpf_prog_add() but
without checking the return value. bpf_prog_add() can fail since 92117d8443
("bpf: fix refcnt overflow"), so we really must check it. Take the reference
right when we assign it to the rq from priv->xdp_prog, and just drop the
reference on error path. Destruction in mlx5e_destroy_rq() looks good, though.

Fixes: 86994156c7 ("net/mlx5e: XDP fast RX drop bpf programs support")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-21 11:25:57 -05:00
Alexander Shishkin e96271f3ed perf/core: Fix address filter parser
The token table passed into match_token() must be null-terminated, which
it currently is not in the perf's address filter string parser, as caught
by Vince's perf_fuzzer and KASAN.

It doesn't blow up otherwise because of the alignment padding of the table
to the next element in the .rodata, which is luck.

Fixing by adding a null-terminator to the token table.

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dvyukov@google.com
Cc: stable@vger.kernel.org # v4.7+
Fixes: 375637bc52 ("perf/core: Introduce address range filtering")
Link: http://lkml.kernel.org/r/877f81f264.fsf@ashishki-desk.ger.corp.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-21 11:28:36 +01:00
Babu Moger e245d99e6c lockdep: Limit static allocations if PROVE_LOCKING_SMALL is defined
Reduce the size of data structure for lockdep entries by half if
PROVE_LOCKING_SMALL if defined. This is used only for sparc.

Signed-off-by: Babu Moger <babu.moger@oracle.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-18 11:33:19 -08:00
Alexey Dobriyan c7d03a00b5 netns: make struct pernet_operations::id unsigned int
Make struct pernet_operations::id unsigned.

There are 2 reasons to do so:

1)
This field is really an index into an zero based array and
thus is unsigned entity. Using negative value is out-of-bound
access by definition.

2)
On x86_64 unsigned 32-bit data which are mixed with pointers
via array indexing or offsets added or subtracted to pointers
are preffered to signed 32-bit data.

"int" being used as an array index needs to be sign-extended
to 64-bit before being used.

	void f(long *p, int i)
	{
		g(p[i]);
	}

  roughly translates to

	movsx	rsi, esi
	mov	rdi, [rsi+...]
	call 	g

MOVSX is 3 byte instruction which isn't necessary if the variable is
unsigned because x86_64 is zero extending by default.

Now, there is net_generic() function which, you guessed it right, uses
"int" as an array index:

	static inline void *net_generic(const struct net *net, int id)
	{
		...
		ptr = ng->ptr[id - 1];
		...
	}

And this function is used a lot, so those sign extensions add up.

Patch snipes ~1730 bytes on allyesconfig kernel (without all junk
messing with code generation):

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)

Unfortunately some functions actually grow bigger.
This is a semmingly random artefact of code generation with register
allocator being used differently. gcc decides that some variable
needs to live in new r8+ registers and every access now requires REX
prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be
used which is longer than [r8]

However, overall balance is in negative direction:

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
	function                                     old     new   delta
	nfsd4_lock                                  3886    3959     +73
	tipc_link_build_proto_msg                   1096    1140     +44
	mac80211_hwsim_new_radio                    2776    2808     +32
	tipc_mon_rcv                                1032    1058     +26
	svcauth_gss_legacy_init                     1413    1429     +16
	tipc_bcbase_select_primary                   379     392     +13
	nfsd4_exchange_id                           1247    1260     +13
	nfsd4_setclientid_confirm                    782     793     +11
		...
	put_client_renew_locked                      494     480     -14
	ip_set_sockfn_get                            730     716     -14
	geneve_sock_add                              829     813     -16
	nfsd4_sequence_done                          721     703     -18
	nlmclnt_lookup_host                          708     686     -22
	nfsd4_lockt                                 1085    1063     -22
	nfs_get_client                              1077    1050     -27
	tcf_bpf_init                                1106    1076     -30
	nfsd4_encode_fattr                          5997    5930     -67
	Total: Before=154856051, After=154854321, chg -0.00%

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-18 10:59:15 -05:00
Josef Bacik f23cc643f9 bpf: fix range arithmetic for bpf map access
I made some invalid assumptions with BPF_AND and BPF_MOD that could result in
invalid accesses to bpf map entries.  Fix this up by doing a few things

1) Kill BPF_MOD support.  This doesn't actually get used by the compiler in real
life and just adds extra complexity.

2) Fix the logic for BPF_AND, don't allow AND of negative numbers and set the
minimum value to 0 for positive AND's.

3) Don't do operations on the ranges if they are set to the limits, as they are
by definition undefined, and allowing arithmetic operations on those values
could make them appear valid when they really aren't.

This fixes the testcase provided by Jann as well as a few other theoretical
problems.

Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-16 13:21:45 -05:00
Martin KaFai Lau 2874aa2e46 bpf: Fix compilation warning in __bpf_lru_list_rotate_inactive
gcc-6.2.1 gives the following warning:
kernel/bpf/bpf_lru_list.c: In function ‘__bpf_lru_list_rotate_inactive.isra.3’:
kernel/bpf/bpf_lru_list.c:201:28: warning: ‘next’ may be used uninitialized in this function [-Wmaybe-uninitialized]

The "next" is currently initialized in the while() loop which must have >=1
iterations.

This patch initializes next to get rid of the compiler warning.

Fixes: 3a08c2fd76 ("bpf: LRU List")
Reported-by: David Miller <davem@davemloft.net>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-16 11:30:56 -05:00
Martin KaFai Lau 8f8449384e bpf: Add BPF_MAP_TYPE_LRU_PERCPU_HASH
Provide a LRU version of the existing BPF_MAP_TYPE_PERCPU_HASH

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 11:50:20 -05:00
Martin KaFai Lau 29ba732acb bpf: Add BPF_MAP_TYPE_LRU_HASH
Provide a LRU version of the existing BPF_MAP_TYPE_HASH.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 11:50:20 -05:00
Martin KaFai Lau fd91de7b3c bpf: Refactor codes handling percpu map
Refactor the codes that populate the value
of a htab_elem in a BPF_MAP_TYPE_PERCPU_HASH
typed bpf_map.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 11:50:20 -05:00
Martin KaFai Lau 961578b634 bpf: Add percpu LRU list
Instead of having a common LRU list, this patch allows a
percpu LRU list which can be selected by specifying a map
attribute.  The map attribute will be added in the later
patch.

While the common use case for LRU is #reads >> #updates,
percpu LRU list allows bpf prog to absorb unusual #updates
under pathological case (e.g. external traffic facing machine which
could be under attack).

Each percpu LRU is isolated from each other.  The LRU nodes (including
free nodes) cannot be moved across different LRU Lists.

Here are the update performance comparison between
common LRU list and percpu LRU list (the test code is
at the last patch):

[root@kerneltest003.31.prn1 ~]# for i in 1 4 8; do echo -n "$i cpus: "; \
./map_perf_test 16 $i | awk '{r += $3}END{print r " updates"}'; done
 1 cpus: 2934082 updates
 4 cpus: 7391434 updates
 8 cpus: 6500576 updates

[root@kerneltest003.31.prn1 ~]# for i in 1 4 8; do echo -n "$i cpus: "; \
./map_perf_test 32 $i | awk '{r += $3}END{printr " updates"}'; done
  1 cpus: 2896553 updates
  4 cpus: 9766395 updates
  8 cpus: 17460553 updates

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 11:50:20 -05:00
Martin KaFai Lau 3a08c2fd76 bpf: LRU List
Introduce bpf_lru_list which will provide LRU capability to
the bpf_htab in the later patch.

* General Thoughts:
1. Target use case.  Read is more often than update.
   (i.e. bpf_lookup_elem() is more often than bpf_update_elem()).
   If bpf_prog does a bpf_lookup_elem() first and then an in-place
   update, it still counts as a read operation to the LRU list concern.
2. It may be useful to think of it as a LRU cache
3. Optimize the read case
   3.1 No lock in read case
   3.2 The LRU maintenance is only done during bpf_update_elem()
4. If there is a percpu LRU list, it will lose the system-wise LRU
   property.  A completely isolated percpu LRU list has the best
   performance but the memory utilization is not ideal considering
   the work load may be imbalance.
5. Hence, this patch starts the LRU implementation with a global LRU
   list with batched operations before accessing the global LRU list.
   As a LRU cache, #read >> #update/#insert operations, it will work well.
6. There is a local list (for each cpu) which is named
   'struct bpf_lru_locallist'.  This local list is not used to sort
   the LRU property.  Instead, the local list is to batch enough
   operations before acquiring the lock of the global LRU list.  More
   details on this later.
7. In the later patch, it allows a percpu LRU list by specifying a
   map-attribute for scalability reason and for use cases that need to
   prepare for the worst (and pathological) case like DoS attack.
   The percpu LRU list is completely isolated from each other and the
   LRU nodes (including free nodes) cannot be moved across the list.  The
   following description is for the global LRU list but mostly applicable
   to the percpu LRU list also.

* Global LRU List:
1. It has three sub-lists: active-list, inactive-list and free-list.
2. The two list idea, active and inactive, is borrowed from the
   page cache.
3. All nodes are pre-allocated and all sit at the free-list (of the
   global LRU list) at the beginning.  The pre-allocation reasoning
   is similar to the existing BPF_MAP_TYPE_HASH.  However,
   opting-out prealloc (BPF_F_NO_PREALLOC) is not supported in
   the LRU map.

* Active/Inactive List (of the global LRU list):
1. The active list, as its name says it, maintains the active set of
   the nodes.  We can think of it as the working set or more frequently
   accessed nodes.  The access frequency is approximated by a ref-bit.
   The ref-bit is set during the bpf_lookup_elem().
2. The inactive list, as its name also says it, maintains a less
   active set of nodes.  They are the candidates to be removed
   from the bpf_htab when we are running out of free nodes.
3. The ordering of these two lists is acting as a rough clock.
   The tail of the inactive list is the older nodes and
   should be released first if the bpf_htab needs free element.

* Rotating the Active/Inactive List (of the global LRU list):
1. It is the basic operation to maintain the LRU property of
   the global list.
2. The active list is only rotated when the inactive list is running
   low.  This idea is similar to the current page cache.
   Inactive running low is currently defined as
   "# of inactive < # of active".
3. The active list rotation always starts from the tail.  It moves
   node without ref-bit set to the head of the inactive list.
   It moves node with ref-bit set back to the head of the active
   list and then clears its ref-bit.
4. The inactive rotation is pretty simply.
   It walks the inactive list and moves the nodes back to the head of
   active list if its ref-bit is set. The ref-bit is cleared after moving
   to the active list.
   If the node does not have ref-bit set, it just leave it as it is
   because it is already in the inactive list.

* Shrinking the Inactive List (of the global LRU list):
1. Shrinking is the operation to get free nodes when the bpf_htab is
   full.
2. It usually only shrinks the inactive list to get free nodes.
3. During shrinking, it will walk the inactive list from the tail,
   delete the nodes without ref-bit set from bpf_htab.
4. If no free node found after step (3), it will forcefully get
   one node from the tail of inactive or active list.  Forcefully is
   in the sense that it ignores the ref-bit.

* Local List:
1. Each CPU has a 'struct bpf_lru_locallist'.  The purpose is to
   batch enough operations before acquiring the lock of the
   global LRU.
2. A local list has two sub-lists, free-list and pending-list.
3. During bpf_update_elem(), it will try to get from the free-list
   of (the current CPU local list).
4. If the local free-list is empty, it will acquire from the
   global LRU list.  The global LRU list can either satisfy it
   by its global free-list or by shrinking the global inactive
   list.  Since we have acquired the global LRU list lock,
   it will try to get at most LOCAL_FREE_TARGET elements
   to the local free list.
5. When a new element is added to the bpf_htab, it will
   first sit at the pending-list (of the local list) first.
   The pending-list will be flushed to the global LRU list
   when it needs to acquire free nodes from the global list
   next time.

* Lock Consideration:
The LRU list has a lock (lru_lock).  Each bucket of htab has a
lock (buck_lock).  If both locks need to be acquired together,
the lock order is always lru_lock -> buck_lock and this only
happens in the bpf_lru_list.c logic.

In hashtab.c, both locks are not acquired together (i.e. one
lock is always released first before acquiring another lock).

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 11:50:20 -05:00
Linus Torvalds 81bcfe5e48 Alexei discovered a race condition in modules failing to load that
can cause a ftrace check to trigger and disable ftrace. This is because
 of the way modules are registered to ftrace. Their functions are
 loaded in the ftrace function tables but set to "disabled" since
 they are still in the process of being loaded by the module. After
 the module is finished, it calls back into the ftrace infrastructure
 to enable it. Looking deeper into the locations that access all the
 functions in the table, I found more locations that should ignore
 the disabled ones.
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Merge tag 'trace-v4.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Alexei discovered a race condition in modules failing to load that can
  cause a ftrace check to trigger and disable ftrace.

  This is because of the way modules are registered to ftrace. Their
  functions are loaded in the ftrace function tables but set to
  "disabled" since they are still in the process of being loaded by the
  module. After the module is finished, it calls back into the ftrace
  infrastructure to enable it.

  Looking deeper into the locations that access all the functions in the
  table, I found more locations that should ignore the disabled ones"

* tag 'trace-v4.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Add more checks for FTRACE_FL_DISABLED in processing ip records
  ftrace: Ignore FTRACE_FL_DISABLED while walking dyn_ftrace records
2016-11-15 08:49:13 -08:00
David S. Miller bb598c1b8c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several cases of bug fixes in 'net' overlapping other changes in
'net-next-.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 10:54:36 -05:00
David Carrillo-Cisneros 864c2357ca perf/core: Do not set cpuctx->cgrp for unscheduled cgroups
Commit:

  db4a835601 ("perf/core: Set cgroup in CPU contexts for new cgroup events")

failed to verify that event->cgrp is actually the scheduled cgroup
in a CPU before setting cpuctx->cgrp. This patch fixes that.

Now that there is a different path for scheduled and unscheduled
cgroup, add a warning to catch when cpuctx->cgrp is still set after
the last cgroup event has been unsheduled.

To verify the bug:

  # Create 2 cgroups.
  mkdir /dev/cgroups/devices/g1
  mkdir /dev/cgroups/devices/g2

  # launch a task, bind it to a cpu and move it to g1
  CPU=2
  while :; do : ; done &
  P=$!

  taskset -pc $CPU $P
  echo $P > /dev/cgroups/devices/g1/tasks

  # monitor g2 (it runs no tasks) and observe output
  perf stat -e cycles -I 1000 -C $CPU -G g2

  #           time             counts unit events
     1.000091408          7,579,527      cycles                    g2
     2.000350111      <not counted>      cycles                    g2
     3.000589181      <not counted>      cycles                    g2
     4.000771428      <not counted>      cycles                    g2

  # note first line that displays that a task run in g2, despite
  # g2 having no tasks. This is because cpuctx->cgrp was wrongly
  # set when context of new event was installed.
  # After applying the fix we obtain the right output:

  perf stat -e cycles -I 1000 -C $CPU -G g2
  #           time             counts unit events
     1.000119615      <not counted>      cycles                    g2
     2.000389430      <not counted>      cycles                    g2
     3.000590962      <not counted>      cycles                    g2

Signed-off-by: David Carrillo-Cisneros <davidcc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Link: http://lkml.kernel.org/r/1478026378-86083-1-git-send-email-davidcc@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-15 14:18:22 +01:00
Linus Torvalds e76d21c40b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix off by one wrt. indexing when dumping /proc/net/route entries,
    from Alexander Duyck.

 2) Fix lockdep splats in iwlwifi, from Johannes Berg.

 3) Cure panic when inserting certain netfilter rules when NFT_SET_HASH
    is disabled, from Liping Zhang.

 4) Memory leak when nft_expr_clone() fails, also from Liping Zhang.

 5) Disable UFO when path will apply IPSEC tranformations, from Jakub
    Sitnicki.

 6) Don't bogusly double cwnd in dctcp module, from Florian Westphal.

 7) skb_checksum_help() should never actually use the value "0" for the
    resulting checksum, that has a special meaning, use CSUM_MANGLED_0
    instead. From Eric Dumazet.

 8) Per-tx/rx queue statistic strings are wrong in qed driver, fix from
    Yuval MIntz.

 9) Fix SCTP reference counting of associations and transports in
    sctp_diag. From Xin Long.

10) When we hit ip6tunnel_xmit() we could have come from an ipv4 path in
    a previous layer or similar, so explicitly clear the ipv6 control
    block in the skb. From Eli Cooper.

11) Fix bogus sleeping inside of inet_wait_for_connect(), from WANG
    Cong.

12) Correct deivce ID of T6 adapter in cxgb4 driver, from Hariprasad
    Shenai.

13) Fix potential access past the end of the skb page frag array in
    tcp_sendmsg(). From Eric Dumazet.

14) 'skb' can legitimately be NULL in inet{,6}_exact_dif_match(). Fix
    from David Ahern.

15) Don't return an error in tcp_sendmsg() if we wronte any bytes
    successfully, from Eric Dumazet.

16) Extraneous unlocks in netlink_diag_dump(), we removed the locking
    but forgot to purge these unlock calls. From Eric Dumazet.

17) Fix memory leak in error path of __genl_register_family(). We leak
    the attrbuf, from WANG Cong.

18) cgroupstats netlink policy table is mis-sized, from WANG Cong.

19) Several XDP bug fixes in mlx5, from Saeed Mahameed.

20) Fix several device refcount leaks in network drivers, from Johan
    Hovold.

21) icmp6_send() should use skb dst device not skb->dev to determine L3
    routing domain. From David Ahern.

22) ip_vs_genl_family sets maxattr incorrectly, from WANG Cong.

23) We leak new macvlan port in some cases of maclan_common_netlink()
    errors. Fix from Gao Feng.

24) Similar to the icmp6_send() fix, icmp_route_lookup() should
    determine L3 routing domain using skb_dst(skb)->dev not skb->dev.
    Also from David Ahern.

25) Several fixes for route offloading and FIB notification handling in
    mlxsw driver, from Jiri Pirko.

26) Properly cap __skb_flow_dissect()'s return value, from Eric Dumazet.

27) Fix long standing regression in ipv4 redirect handling, wrt.
    validating the new neighbour's reachability. From Stephen Suryaputra
    Lin.

28) If sk_filter() trims the packet excessively, handle it reasonably in
    tcp input instead of exploding. From Eric Dumazet.

29) Fix handling of napi hash state when copying channels in sfc driver,
    from Bert Kenward.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (121 commits)
  mlxsw: spectrum_router: Flush FIB tables during fini
  net: stmmac: Fix lack of link transition for fixed PHYs
  sctp: change sk state only when it has assocs in sctp_shutdown
  bnx2: Wait for in-flight DMA to complete at probe stage
  Revert "bnx2: Reset device during driver initialization"
  ps3_gelic: fix spelling mistake in debug message
  net: ethernet: ixp4xx_eth: fix spelling mistake in debug message
  ibmvnic: Fix size of debugfs name buffer
  ibmvnic: Unmap ibmvnic_statistics structure
  sfc: clear napi_hash state when copying channels
  mlxsw: spectrum_router: Correctly dump neighbour activity
  mlxsw: spectrum: Fix refcount bug on span entries
  bnxt_en: Fix VF virtual link state.
  bnxt_en: Fix ring arithmetic in bnxt_setup_tc().
  Revert "include/uapi/linux/atm_zatm.h: include linux/time.h"
  tcp: take care of truncations done by sk_filter()
  ipv4: use new_gw for redirect neigh lookup
  r8152: Fix error path in open function
  net: bpqether.h: remove if_ether.h guard
  net: __skb_flow_dissect() must cap its return value
  ...
2016-11-14 14:15:53 -08:00
Steven Rostedt (Red Hat) 546fece4ea ftrace: Add more checks for FTRACE_FL_DISABLED in processing ip records
When a module is first loaded and its function ip records are added to the
ftrace list of functions to modify, they are set to DISABLED, as their text
is still in a read only state. When the module is fully loaded, and can be
updated, the flag is cleared, and if their's any functions that should be
tracing them, it is updated at that moment.

But there's several locations that do record accounting and should ignore
records that are marked as disabled, or they can cause issues.

Alexei already fixed one location, but others need to be addressed.

Cc: stable@vger.kernel.org
Fixes: b7ffffbb46 "ftrace: Add infrastructure for delayed enabling of module functions"
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-14 16:31:49 -05:00
Alexei Starovoitov 977c1f9c8c ftrace: Ignore FTRACE_FL_DISABLED while walking dyn_ftrace records
ftrace_shutdown() checks for sanity of ftrace records
and if dyn_ftrace->flags is not zero, it will warn.
It can happen that 'flags' are set to FTRACE_FL_DISABLED at this point,
since some module was loaded, but before ftrace_module_enable()
cleared the flags for this module.

In other words the module.c is doing:
ftrace_module_init(mod); // calls ftrace_update_code() that sets flags=FTRACE_FL_DISABLED
... // here ftrace_shutdown() is called that warns, since
err = prepare_coming_module(mod); // didn't have a chance to clear FTRACE_FL_DISABLED

Fix it by ignoring disabled records.
It's similar to what __ftrace_hash_rec_update() is already doing.

Link: http://lkml.kernel.org/r/1478560460-3818619-1-git-send-email-ast@fb.com

Cc: stable@vger.kernel.org
Fixes: b7ffffbb46 "ftrace: Add infrastructure for delayed enabling of module functions"
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-11-14 16:31:41 -05:00
Mickaël Salaün 535e7b4b5e bpf: Use u64_to_user_ptr()
Replace the custom u64_to_ptr() function with the u64_to_user_ptr()
macro.

Signed-off-by: Mickaël Salaün <mic@digikod.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-14 16:23:08 -05:00
Linus Torvalds f5c9f9c723 Revert "printk: make reading the kernel log flush pending lines"
This reverts commit bfd8d3f23b.

It turns out that this flushes things much too aggressiverly, and causes
lines to break up when the system logger races with new continuation
lines being printed.

There's a pending patch to make printk() flushing much more
straightforward, but it's too invasive for 4.9, so in the meantime let's
just not make the system message logging flush continuation lines.
They'll be flushed by the final newline anyway.

Suggested-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-14 09:31:52 -08:00
Linus Torvalds 5d69561b7b Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fix from Ingo Molnar:
 "This fixes a genirq regression that resulted in the Intel/Broxton
  pinctrl/GPIO driver (and possibly others) spewing warnings"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Use irq type from irqdata instead of irqdesc
2016-11-14 08:34:56 -08:00
Daniel Borkmann c540594f86 bpf, mlx4: fix prog refcount in mlx4_en_try_alloc_resources error path
Commit 67f8b1dcb9 ("net/mlx4_en: Refactor the XDP forwarding rings
scheme") added a bug in that the prog's reference count is not dropped
in the error path when mlx4_en_try_alloc_resources() is failing from
mlx4_xdp_set().

We previously took bpf_prog_add(prog, priv->rx_ring_num - 1), that we
need to release again. Earlier in the call path, dev_change_xdp_fd()
itself holds a reference to the prog as well (hence the '- 1' in the
bpf_prog_add()), so a simple atomic_sub() is safe to use here. When
an error is propagated, then bpf_prog_put() is called eventually from
dev_change_xdp_fd()

Fixes: 67f8b1dcb9 ("net/mlx4_en: Refactor the XDP forwarding rings scheme")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-12 23:31:57 -05:00
Linus Torvalds b9f659b810 Power management fixes for v4.9-rc5
- Prevent the PM core from attempting to suspend parent devices
    if any of their children, whose suspend callbacks were invoked
    asynchronously, have failed to suspend during the "late" and
    "noirq" phases of system-wide suspend of devices (Brian Norris).
 
  - Prevent the boot-time system suspend test code from leaking a
    reference to the RTC device used by it (Johan Hovold).
 
  - Fix cpupower to use the return value of one of its library
    functions correctly and restore the correct behavior of it
    when used for setting cpufreq tunables broken during the 4.7
    development cycle (Laura Abbott).
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Merge tag 'pm-4.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix two bugs in error code paths in the PM core (system-wide
  suspend of devices), a device reference leak in the boot-time suspend
  test code and a cpupower utility regression from the 4.7 cycle.

  Specifics:

   - Prevent the PM core from attempting to suspend parent devices if
     any of their children, whose suspend callbacks were invoked
     asynchronously, have failed to suspend during the "late" and
     "noirq" phases of system-wide suspend of devices (Brian Norris).

   - Prevent the boot-time system suspend test code from leaking a
     reference to the RTC device used by it (Johan Hovold).

   - Fix cpupower to use the return value of one of its library
     functions correctly and restore the correct behavior of it when
     used for setting cpufreq tunables broken during the 4.7 development
     cycle (Laura Abbott)"

* tag 'pm-4.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / sleep: don't suspend parent when async child suspend_{noirq, late} fails
  PM / sleep: fix device reference leak in test_suspend
  cpupower: Correct return type of cpu_power_is_cpu_online() in cpufreq-set
2016-11-11 16:54:23 -08:00
Rafael J. Wysocki cd16f3dcdb Merge branches 'pm-tools-fixes' and 'pm-sleep-fixes'
* pm-tools-fixes:
  cpupower: Correct return type of cpu_power_is_cpu_online() in cpufreq-set

* pm-sleep-fixes:
  PM / sleep: don't suspend parent when async child suspend_{noirq, late} fails
  PM / sleep: fix device reference leak in test_suspend
2016-11-11 23:24:58 +01:00
Hans de Goede c6c7d83b9c Revert "console: don't prefer first registered if DT specifies stdout-path"
This reverts commit 05fd007e46 ("console: don't prefer first
registered if DT specifies stdout-path").

The reverted commit changes existing behavior on which many ARM boards
rely.  Many ARM small-board-computers, like e.g.  the Raspberry Pi have
both a video output and a serial console.  Depending on whether the user
is using the device as a more regular computer; or as a headless device
we need to have the console on either one or the other.

Many users rely on the kernel behavior of the console being present on
both outputs, before the reverted commit the console setup with no
console= kernel arguments on an ARM board which sets stdout-path in dt
would look like this:

  [root@localhost ~]# cat /proc/consoles
  ttyS0                -W- (EC p a)    4:64
  tty0                 -WU (E  p  )    4:1

Where as after the reverted commit, it looks like this:

  [root@localhost ~]# cat /proc/consoles
  ttyS0                -W- (EC p a)    4:64

This commit reverts commit 05fd007e46 ("console: don't prefer first
registered if DT specifies stdout-path") restoring the original
behavior.

Fixes: 05fd007e46 ("console: don't prefer first registered if DT specifies stdout-path")
Link: http://lkml.kernel.org/r/20161104121135.4780-2-hdegoede@redhat.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Cc: Thorsten Leemhuis <regressions@leemhuis.info>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-11 08:12:37 -08:00
Tobias Klauser de464375da bpf: Remove unused but set variables
Remove the unused but set variables min_set and max_set in
adjust_reg_min_max_vals to fix the following warning when building with
'W=1':

  kernel/bpf/verifier.c:1483:7: warning: variable ‘min_set’ set but not used [-Wunused-but-set-variable]

There is no warning about max_set being unused, but since it is only
used in the assignment of min_set it can be removed as well.

They were introduced in commit 484611357c ("bpf: allow access into map
value arrays") but seem to have never been used.

Cc: Josef Bacik <jbacik@fb.com>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-09 21:15:00 -05:00
Thomas Gleixner 7ee7e87dfb genirq: Use irq type from irqdata instead of irqdesc
The type flags in the irq descriptor are there for historical reasons and
only updated via irq_modify_status() or irq_set_type(). Both functions also
update the type flags in irqdata. __setup_irq() is the only left over user
of the type flags in the irq descriptor.

If __setup_irq() is called with empty irq type flags, then the type flags
are retrieved from irqdata. If an interrupt is shared, then the type flags
are compared with the type flags stored in the irq descriptor. 

On x86 the ioapic does not have a irq_set_type() callback because the type
is defined in the BIOS tables and cannot be changed. The type is stored in
irqdata at setup time without updating the type data in the irq
descriptor. As a result the comparison described above fails.

There is no point in updating the irq descriptor flags because the only
relevant storage is irqdata. Use the type flags from irqdata for both
retrieval and comparison in __setup_irq() instead.

Aside of that the print out in case of non matching type flags has the old
and new type flags arguments flipped. Fix that as well.

For correctness sake the flags stored in the irq descriptor should be
removed, but this is beyond the scope of this bugfix and will be done in a
later patch.

Fixes: 4b357daed6 ("genirq: Look-up trigger type if not specified by caller")
Reported-and-tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Jon Hunter <jonathanh@nvidia.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1611072020360.3501@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-08 15:15:19 +01:00
Daniel Borkmann 20b2b24f91 bpf: fix map not being uncharged during map creation failure
In map_create(), we first find and create the map, then once that
suceeded, we charge it to the user's RLIMIT_MEMLOCK, and then fetch
a new anon fd through anon_inode_getfd(). The problem is, once the
latter fails f.e. due to RLIMIT_NOFILE limit, then we only destruct
the map via map->ops->map_free(), but without uncharging the previously
locked memory first. That means that the user_struct allocation is
leaked as well as the accounted RLIMIT_MEMLOCK memory not released.
Make the label names in the fix consistent with bpf_prog_load().

Fixes: aaac3ba95e ("bpf: charge user for creation of BPF maps and programs")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-07 13:22:26 -05:00
Daniel Borkmann 483bed2b0d bpf: fix htab map destruction when extra reserve is in use
Commit a6ed3ea65d ("bpf: restore behavior of bpf_map_update_elem")
added an extra per-cpu reserve to the hash table map to restore old
behaviour from pre prealloc times. When non-prealloc is in use for a
map, then problem is that once a hash table extra element has been
linked into the hash-table, and the hash table is destroyed due to
refcount dropping to zero, then htab_map_free() -> delete_all_elements()
will walk the whole hash table and drop all elements via htab_elem_free().
The problem is that the element from the extra reserve is first fed
to the wrong backend allocator and eventually freed twice.

Fixes: a6ed3ea65d ("bpf: restore behavior of bpf_map_update_elem")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-07 13:20:52 -05:00
Linus Torvalds ffbcbfca84 Merge branches 'sched-urgent-for-linus' and 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull stack vmap fixups from Thomas Gleixner:
 "Two small patches related to sched_show_task():

   - make sure to hold a reference on the task stack while accessing it

   - remove the thread_saved_pc printout

  .. and add a sanity check into release_task_stack() to catch problems
  with task stack references"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Remove pointless printout in sched_show_task()
  sched/core: Fix oops in sched_show_task()

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  fork: Add task stack refcounting sanity check and prevent premature task stack freeing
2016-11-05 11:46:02 -07:00
WANG Cong 243d521261 taskstats: fix the length of cgroupstats_cmd_get_policy
cgroupstats_cmd_get_policy is [CGROUPSTATS_CMD_ATTR_MAX+1],
taskstats_cmd_get_policy[TASKSTATS_CMD_ATTR_MAX+1],
but their family.maxattr is TASKSTATS_CMD_ATTR_MAX.
CGROUPSTATS_CMD_ATTR_MAX is less than TASKSTATS_CMD_ATTR_MAX,
so we could end up accessing out-of-bound.

Change cgroupstats_cmd_get_policy to TASKSTATS_CMD_ATTR_MAX+1,
this is safe because the rest are initialized to 0's.

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-03 16:55:58 -04:00
Linus Torvalds 8243d55977 sched/core: Remove pointless printout in sched_show_task()
In sched_show_task() we print out a useless hex number, not even a
symbol, and there's a big question mark whether this even makes sense
anyway, I suspect we should just remove it all.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: brgerst@gmail.com
Cc: jann@thejh.net
Cc: keescook@chromium.org
Cc: linux-api@vger.kernel.org
Cc: tycho.andersen@canonical.com
Link: http://lkml.kernel.org/r/CA+55aFzphURPFzAvU4z6Moy7ZmimcwPuUdYU8bj9z0J+S8X1rw@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-03 07:31:34 +01:00
Tetsuo Handa 382005027f sched/core: Fix oops in sched_show_task()
When CONFIG_THREAD_INFO_IN_TASK=y, it is possible that an exited thread
remains in the task list after its stack pointer was already set to NULL.

Therefore, thread_saved_pc() and stack_not_used() in sched_show_task()
will trigger NULL pointer dereference if an attempt to dump such thread's
traces (e.g. SysRq-t, khungtaskd) is made.

Since show_stack() in sched_show_task() calls try_get_task_stack() and
sched_show_task() is called from interrupt context, calling
try_get_task_stack() from sched_show_task() will be safe as well.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: brgerst@gmail.com
Cc: jann@thejh.net
Cc: keescook@chromium.org
Cc: linux-api@vger.kernel.org
Cc: tycho.andersen@canonical.com
Link: http://lkml.kernel.org/r/201611021950.FEJ34368.HFFJOOMLtQOVSF@I-love.SAKURA.ne.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-03 07:27:34 +01:00
Johan Hovold ceb75787bc PM / sleep: fix device reference leak in test_suspend
Make sure to drop the reference taken by class_find_device() after
opening the RTC device.

Fixes: 77437fd4e6 (pm: boot time suspend selftest)
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-11-02 05:10:04 +01:00
Andy Lutomirski 405c075971 fork: Add task stack refcounting sanity check and prevent premature task stack freeing
If something goes wrong with task stack refcounting and a stack
refcount hits zero too early, warn and leak it rather than
potentially freeing it early (and silently).

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/f29119c783a9680a4b4656e751b6123917ace94b.1477926663.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-01 07:39:17 +01:00
Daniel Borkmann 0f98621bef bpf, inode: add support for symlinks and fix mtime/ctime
While commit bb35a6ef7d ("bpf, inode: allow for rename and link ops")
added support for hard links that can be used for prog and map nodes,
this work adds simple symlink support, which can be used f.e. for
directories also when unpriviledged and works with cmdline tooling that
understands S_IFLNK anyway. Since the switch in e27f4a942a ("bpf: Use
mount_nodev not mount_ns to mount the bpf filesystem"), there can be
various mount instances with mount_nodev() and thus hierarchy can be
flattened to facilitate object sharing. Thus, we can keep bpf tooling
also working by repointing paths.

Most of the functionality can be used from vfs library operations. The
symlink is stored in the inode itself, that is in i_link, which is
sufficient in our case as opposed to storing it in the page cache.
While at it, I noticed that bpf_mkdir() and bpf_mkobj() don't update
the directories mtime and ctime, so add a common helper for it called
bpf_dentry_finalize() that takes care of it for all cases now.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-31 15:28:11 -04:00
David S. Miller 27058af401 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Mostly simple overlapping changes.

For example, David Ahern's adjacency list revamp in 'net-next'
conflicted with an adjacency list traversal bug fix in 'net'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-30 12:42:58 -04:00
Thomas Graf ebb676daa1 bpf: Print function name in addition to function id
The verifier currently prints raw function ids when printing CALL
instructions or when complaining:

	5: (85) call 23
	unknown func 23

print a meaningful function name instead:

	5: (85) call bpf_redirect#23
	unknown func bpf_redirect#23

Moves the function documentation to a single comment and renames all
helpers names in the list to conform to the bpf_ prefix notation so
they can be greped in the kernel source.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-29 15:55:13 -04:00