Commit Graph

32391 Commits

Author SHA1 Message Date
Linus Torvalds
570203ec83 Merge branch 'akpm' (patches from Andrew)
Merge vm fixes from Andrew Morton:
 "5 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm/sparse: fix kernel crash with pfn_section_valid check
  mm: fork: fix kernel_stack memcg stats for various stack implementations
  hugetlb_cgroup: fix illegal access to memory
  drivers/base/memory.c: indicate all memory blocks as removable
  mm/swapfile.c: move inode_lock out of claim_swapfile
2020-03-29 10:40:31 -07:00
Linus Torvalds
01af08bd24 A single bugfix to prevent reference leaks in irq affinity notifiers.
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Merge tag 'irq-urgent-2020-03-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq fix from Thomas Gleixner:
 "A single bugfix to prevent reference leaks in irq affinity notifiers"

* tag 'irq-urgent-2020-03-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Fix reference leaks on irq affinity notifiers
2020-03-29 10:07:00 -07:00
Roman Gushchin
8380ce4790 mm: fork: fix kernel_stack memcg stats for various stack implementations
Depending on CONFIG_VMAP_STACK and the THREAD_SIZE / PAGE_SIZE ratio the
space for task stacks can be allocated using __vmalloc_node_range(),
alloc_pages_node() and kmem_cache_alloc_node().

In the first and the second cases page->mem_cgroup pointer is set, but
in the third it's not: memcg membership of a slab page should be
determined using the memcg_from_slab_page() function, which looks at
page->slab_cache->memcg_params.memcg .  In this case, using
mod_memcg_page_state() (as in account_kernel_stack()) is incorrect:
page->mem_cgroup pointer is NULL even for pages charged to a non-root
memory cgroup.

It can lead to kernel_stack per-memcg counters permanently showing 0 on
some architectures (depending on the configuration).

In order to fix it, let's introduce a mod_memcg_obj_state() helper,
which takes a pointer to a kernel object as a first argument, uses
mem_cgroup_from_obj() to get a RCU-protected memcg pointer and calls
mod_memcg_state().  It allows to handle all possible configurations
(CONFIG_VMAP_STACK and various THREAD_SIZE/PAGE_SIZE values) without
spilling any memcg/kmem specifics into fork.c .

Note: This is a special version of the patch created for stable
backports.  It contains code from the following two patches:
  - mm: memcg/slab: introduce mem_cgroup_from_obj()
  - mm: fork: fix kernel_stack memcg stats for various stack implementations

[guro@fb.com: introduce mem_cgroup_from_obj()]
  Link: http://lkml.kernel.org/r/20200324004221.GA36662@carbon.dhcp.thefacebook.com
Fixes: 4d96ba3530 ("mm: memcg/slab: stop setting page->mem_cgroup pointer for slab pages")
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Bharata B Rao <bharata@linux.ibm.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200303233550.251375-1-guro@fb.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-03-29 09:47:05 -07:00
David S. Miller
a0ba26f37e Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2020-03-27

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

We've added 3 non-merge commits during the last 4 day(s) which contain
a total of 4 files changed, 25 insertions(+), 20 deletions(-).

The main changes are:

1) Explicitly memset the bpf_attr structure on bpf() syscall to avoid
   having to rely on compiler to do so. Issues have been noticed on
   some compilers with padding and other oddities where the request was
   then unexpectedly rejected, from Greg Kroah-Hartman.

2) Sanitize the bpf_struct_ops TCP congestion control name in order to
   avoid problematic characters such as whitespaces, from Martin KaFai Lau.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-27 16:18:51 -07:00
Linus Torvalds
1b649e0bca Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Fix deadlock in bpf_send_signal() from Yonghong Song.

 2) Fix off by one in kTLS offload of mlx5, from Tariq Toukan.

 3) Add missing locking in iwlwifi mvm code, from Avraham Stern.

 4) Fix MSG_WAITALL handling in rxrpc, from David Howells.

 5) Need to hold RTNL mutex in tcindex_partial_destroy_work(), from Cong
    Wang.

 6) Fix producer race condition in AF_PACKET, from Willem de Bruijn.

 7) cls_route removes the wrong filter during change operations, from
    Cong Wang.

 8) Reject unrecognized request flags in ethtool netlink code, from
    Michal Kubecek.

 9) Need to keep MAC in reset until PHY is up in bcmgenet driver, from
    Doug Berger.

10) Don't leak ct zone template in act_ct during replace, from Paul
    Blakey.

11) Fix flushing of offloaded netfilter flowtable flows, also from Paul
    Blakey.

12) Fix throughput drop during tx backpressure in cxgb4, from Rahul
    Lakkireddy.

13) Don't let a non-NULL skb->dev leave the TCP stack, from Eric
    Dumazet.

14) TCP_QUEUE_SEQ socket option has to update tp->copied_seq as well,
    also from Eric Dumazet.

15) Restrict macsec to ethernet devices, from Willem de Bruijn.

16) Fix reference leak in some ethtool *_SET handlers, from Michal
    Kubecek.

17) Fix accidental disabling of MSI for some r8169 chips, from Heiner
    Kallweit.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (138 commits)
  net: Fix CONFIG_NET_CLS_ACT=n and CONFIG_NFT_FWD_NETDEV={y, m} build
  net: ena: Add PCI shutdown handler to allow safe kexec
  selftests/net/forwarding: define libs as TEST_PROGS_EXTENDED
  selftests/net: add missing tests to Makefile
  r8169: re-enable MSI on RTL8168c
  net: phy: mdio-bcm-unimac: Fix clock handling
  cxgb4/ptp: pass the sign of offset delta in FW CMD
  net: dsa: tag_8021q: replace dsa_8021q_remove_header with __skb_vlan_pop
  net: cbs: Fix software cbs to consider packet sending time
  net/mlx5e: Do not recover from a non-fatal syndrome
  net/mlx5e: Fix ICOSQ recovery flow with Striding RQ
  net/mlx5e: Fix missing reset of SW metadata in Striding RQ reset
  net/mlx5e: Enhance ICOSQ WQE info fields
  net/mlx5_core: Set IB capability mask1 to fix ib_srpt connection failure
  selftests: netfilter: add nfqueue test case
  netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress
  netfilter: nft_fwd_netdev: validate family and chain type
  netfilter: nft_set_rbtree: Detect partial overlaps on insertion
  netfilter: nft_set_rbtree: Introduce and use nft_rbtree_interval_start()
  netfilter: nft_set_pipapo: Separate partial and complete overlap cases on insertion
  ...
2020-03-25 13:58:05 -07:00
Joerg Roedel
763802b53a x86/mm: split vmalloc_sync_all()
Commit 3f8fd02b1b ("mm/vmalloc: Sync unmappings in
__purge_vmap_area_lazy()") introduced a call to vmalloc_sync_all() in
the vunmap() code-path.  While this change was necessary to maintain
correctness on x86-32-pae kernels, it also adds additional cycles for
architectures that don't need it.

Specifically on x86-64 with CONFIG_VMAP_STACK=y some people reported
severe performance regressions in micro-benchmarks because it now also
calls the x86-64 implementation of vmalloc_sync_all() on vunmap().  But
the vmalloc_sync_all() implementation on x86-64 is only needed for newly
created mappings.

To avoid the unnecessary work on x86-64 and to gain the performance
back, split up vmalloc_sync_all() into two functions:

	* vmalloc_sync_mappings(), and
	* vmalloc_sync_unmappings()

Most call-sites to vmalloc_sync_all() only care about new mappings being
synchronized.  The only exception is the new call-site added in the
above mentioned commit.

Shile Zhang directed us to a report of an 80% regression in reaim
throughput.

Fixes: 3f8fd02b1b ("mm/vmalloc: Sync unmappings in __purge_vmap_area_lazy()")
Reported-by: kernel test robot <oliver.sang@intel.com>
Reported-by: Shile Zhang <shile.zhang@linux.alibaba.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Borislav Petkov <bp@suse.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>	[GHES]
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20191009124418.8286-1-joro@8bytes.org
Link: https://lists.01.org/hyperkitty/list/lkp@lists.01.org/thread/4D3JPPHBNOSPFK2KEPC6KGKS6J25AIDB/
Link: http://lkml.kernel.org/r/20191113095530.228959-1-shile.zhang@linux.alibaba.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-03-21 18:56:06 -07:00
Edward Cree
df81dfcfd6 genirq: Fix reference leaks on irq affinity notifiers
The handling of notify->work did not properly maintain notify->kref in two
 cases:
1) where the work was already scheduled, another irq_set_affinity_locked()
   would get the ref and (no-op-ly) schedule the work.  Thus when
   irq_affinity_notify() ran, it would drop the original ref but not the
   additional one.
2) when cancelling the (old) work in irq_set_affinity_notifier(), if there
   was outstanding work a ref had been got for it but was never put.
Fix both by checking the return values of the work handling functions
 (schedule_work() for (1) and cancel_work_sync() for (2)) and put the
 extra ref if the return value indicates preexisting work.

Fixes: cd7eab44e9 ("genirq: Add IRQ affinity notifiers")
Fixes: 59c39840f5 ("genirq: Prevent use-after-free and work list corruption")
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ben Hutchings <ben@decadent.org.uk>
Link: https://lkml.kernel.org/r/24f5983f-2ab5-e83a-44ee-a45b5f9300f5@solarflare.com
2020-03-21 17:32:46 +01:00
Greg Kroah-Hartman
5c6f258879 bpf: Explicitly memset some bpf info structures declared on the stack
Trying to initialize a structure with "= {};" will not always clean out
all padding locations in a structure. So be explicit and call memset to
initialize everything for a number of bpf information structures that
are then copied from userspace, sometimes from smaller memory locations
than the size of the structure.

Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200320162258.GA794295@kroah.com
2020-03-20 21:05:22 +01:00
Greg Kroah-Hartman
8096f22942 bpf: Explicitly memset the bpf_attr structure
For the bpf syscall, we are relying on the compiler to properly zero out
the bpf_attr union that we copy userspace data into. Unfortunately that
doesn't always work properly, padding and other oddities might not be
correctly zeroed, and in some tests odd things have been found when the
stack is pre-initialized to other values.

Fix this by explicitly memsetting the structure to 0 before using it.

Reported-by: Maciej Żenczykowski <maze@google.com>
Reported-by: John Stultz <john.stultz@linaro.org>
Reported-by: Alexander Potapenko <glider@google.com>
Reported-by: Alistair Delva <adelva@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://android-review.googlesource.com/c/kernel/common/+/1235490
Link: https://lore.kernel.org/bpf/20200320094813.GA421650@kroah.com
2020-03-20 21:04:30 +01:00
Martin KaFai Lau
8e7ae2518f bpf: Sanitize the bpf_struct_ops tcp-cc name
The bpf_struct_ops tcp-cc name should be sanitized in order to
avoid problematic chars (e.g. whitespaces).

This patch reuses the bpf_obj_name_cpy() for accepting the same set
of characters in order to keep a consistent bpf programming experience.
A "size" param is added.  Also, the strlen is returned on success so
that the caller (like the bpf_tcp_ca here) can error out on empty name.
The existing callers of the bpf_obj_name_cpy() only need to change the
testing statement to "if (err < 0)".  For all these existing callers,
the err will be overwritten later, so no extra change is needed
for the new strlen return value.

v3:
  - reverse xmas tree style
v2:
  - Save the orig_src to avoid "end - size" (Andrii)

Fixes: 0baf26b0fc ("bpf: tcp: Support tcp_congestion_ops in bpf")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200314010209.1131542-1-kafai@fb.com
2020-03-17 20:40:19 +01:00
Linus Torvalds
34d5a4b336 Fix for yet another subtle futex issue. The futex code used ihold() to
prevent inodes from vanishing, but ihold() does not guarantee inode
 persistence. Replace the inode pointer with a per boot, machine wide,
 unique inode identifier. The second commit fixes the breakage of the hash
 mechanism whihc causes a 100% performance regression.
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Merge tag 'locking-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull futex fix from Thomas Gleixner:
 "Fix for yet another subtle futex issue.

  The futex code used ihold() to prevent inodes from vanishing, but
  ihold() does not guarantee inode persistence. Replace the inode
  pointer with a per boot, machine wide, unique inode identifier.

  The second commit fixes the breakage of the hash mechanism which
  causes a 100% performance regression"

* tag 'locking-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  futex: Unbreak futex hashing
  futex: Fix inode life-time issue
2020-03-15 12:55:52 -07:00
Linus Torvalds
ffe6da91b0 A single fix adding the missing time namespace adjustment in sys/sysinfo
which caused sys/sysinfo to be inconsistent with /proc/uptime when read
 from a task inside a time namespace.
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Merge tag 'timers-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fix from Thomas Gleixner:
 "A single fix adding the missing time namespace adjustment in
  sys/sysinfo which caused sys/sysinfo to be inconsistent with
  /proc/uptime when read from a task inside a time namespace"

* tag 'timers-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sys/sysinfo: Respect boottime inside time namespace
2020-03-15 12:48:21 -07:00
David S. Miller
242a6df688 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Alexei Starovoitov says:

====================
pull-request: bpf 2020-03-12

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

We've added 12 non-merge commits during the last 8 day(s) which contain
a total of 12 files changed, 161 insertions(+), 15 deletions(-).

The main changes are:

1) Andrii fixed two bugs in cgroup-bpf.

2) John fixed sockmap.

3) Luke fixed x32 jit.

4) Martin fixed two issues in struct_ops.

5) Yonghong fixed bpf_send_signal.

6) Yoshiki fixed BTF enum.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-13 11:13:45 -07:00
Linus Torvalds
1b51f69461 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:
 "It looks like a decent sized set of fixes, but a lot of these are one
  liner off-by-one and similar type changes:

   1) Fix netlink header pointer to calcular bad attribute offset
      reported to user. From Pablo Neira Ayuso.

   2) Don't double clear PHY interrupts when ->did_interrupt is set,
      from Heiner Kallweit.

   3) Add missing validation of various (devlink, nl802154, fib, etc.)
      attributes, from Jakub Kicinski.

   4) Missing *pos increments in various netfilter seq_next ops, from
      Vasily Averin.

   5) Missing break in of_mdiobus_register() loop, from Dajun Jin.

   6) Don't double bump tx_dropped in veth driver, from Jiang Lidong.

   7) Work around FMAN erratum A050385, from Madalin Bucur.

   8) Make sure ARP header is pulled early enough in bonding driver,
      from Eric Dumazet.

   9) Do a cond_resched() during multicast processing of ipvlan and
      macvlan, from Mahesh Bandewar.

  10) Don't attach cgroups to unrelated sockets when in interrupt
      context, from Shakeel Butt.

  11) Fix tpacket ring state management when encountering unknown GSO
      types. From Willem de Bruijn.

  12) Fix MDIO bus PHY resume by checking mdio_bus_phy_may_suspend()
      only in the suspend context. From Heiner Kallweit"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (112 commits)
  net: systemport: fix index check to avoid an array out of bounds access
  tc-testing: add ETS scheduler to tdc build configuration
  net: phy: fix MDIO bus PM PHY resuming
  net: hns3: clear port base VLAN when unload PF
  net: hns3: fix RMW issue for VLAN filter switch
  net: hns3: fix VF VLAN table entries inconsistent issue
  net: hns3: fix "tc qdisc del" failed issue
  taprio: Fix sending packets without dequeueing them
  net: mvmdio: avoid error message for optional IRQ
  net: dsa: mv88e6xxx: Add missing mask of ATU occupancy register
  net: memcg: fix lockdep splat in inet_csk_accept()
  s390/qeth: implement smarter resizing of the RX buffer pool
  s390/qeth: refactor buffer pool code
  s390/qeth: use page pointers to manage RX buffer pool
  seg6: fix SRv6 L2 tunnels to use IANA-assigned protocol number
  net: dsa: Don't instantiate phylink for CPU/DSA ports unless needed
  net/packet: tpacket_rcv: do not increment ring index on drop
  sxgbe: Fix off by one in samsung driver strncpy size arg
  net: caif: Add lockdep expression to RCU traversal primitive
  MAINTAINERS: remove Sathya Perla as Emulex NIC maintainer
  ...
2020-03-12 16:19:19 -07:00
Linus Torvalds
addcb1d0ee for-linus-2020-03-10
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Merge tag 'for-linus-2020-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull thread fix from Christian Brauner:
 "This contains a single fix for a regression which was introduced when
  we introduced the ability to select a specific pid at process creation
  time.

  When this feature is requested, the error value will be set to -EPERM
  after exiting the pid allocation loop. This caused EPERM to be
  returned when e.g. the init process/child subreaper of the pid
  namespace has already died where we used to return ENOMEM before.

  The first patch here simply fixes the regression by unconditionally
  setting the return value back to ENOMEM again once we've successfully
  allocated the requested pid number. This should be easy to backport to
  v5.5.

  The second patch adds a comment explaining that we must keep returning
  ENOMEM since we've been doing it for a long time and have explicitly
  documented this behavior for userspace. This seemed worthwhile because
  we now have at least two separate example where people tried to change
  the return value to something other than ENOMEM (The first version of
  the regression fix did that too and the commit message links to an
  earlier patch that tried to do the same.).

  I have a simple regression test to make sure we catch this regression
  in the future but since that introduces a whole new selftest subdir
  and test files I'll keep this for v5.7"

* tag 'for-linus-2020-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  pid: make ENOMEM return value more obvious
  pid: Fix error return value in some cases
2020-03-11 10:00:41 -07:00
Linus Torvalds
36feb99630 Have ftrace lookup_rec() return a consistent record otherwise it
can break live patching.
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Merge tag 'trace-v5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull ftrace fix from Steven Rostedt:
 "Have ftrace lookup_rec() return a consistent record otherwise it can
  break live patching"

* tag 'trace-v5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace: Return the first found result in lookup_rec()
2020-03-11 09:54:59 -07:00
Artem Savkov
d9815bff6b ftrace: Return the first found result in lookup_rec()
It appears that ip ranges can overlap so. In that case lookup_rec()
returns whatever results it got last even if it found nothing in last
searched page.

This breaks an obscure livepatch late module patching usecase:
  - load livepatch
  - load the patched module
  - unload livepatch
  - try to load livepatch again

To fix this return from lookup_rec() as soon as it found the record
containing searched-for ip. This used to be this way prior lookup_rec()
introduction.

Link: http://lkml.kernel.org/r/20200306174317.21699-1-asavkov@redhat.com

Cc: stable@vger.kernel.org
Fixes: 7e16f581a8 ("ftrace: Separate out functionality from ftrace_location_range()")
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-03-11 10:37:12 -04:00
Shakeel Butt
e876ecc67d cgroup: memcg: net: do not associate sock with unrelated cgroup
We are testing network memory accounting in our setup and noticed
inconsistent network memory usage and often unrelated cgroups network
usage correlates with testing workload. On further inspection, it
seems like mem_cgroup_sk_alloc() and cgroup_sk_alloc() are broken in
irq context specially for cgroup v1.

mem_cgroup_sk_alloc() and cgroup_sk_alloc() can be called in irq context
and kind of assumes that this can only happen from sk_clone_lock()
and the source sock object has already associated cgroup. However in
cgroup v1, where network memory accounting is opt-in, the source sock
can be unassociated with any cgroup and the new cloned sock can get
associated with unrelated interrupted cgroup.

Cgroup v2 can also suffer if the source sock object was created by
process in the root cgroup or if sk_alloc() is called in irq context.
The fix is to just do nothing in interrupt.

WARNING: Please note that about half of the TCP sockets are allocated
from the IRQ context, so, memory used by such sockets will not be
accouted by the memcg.

The stack trace of mem_cgroup_sk_alloc() from IRQ-context:

CPU: 70 PID: 12720 Comm: ssh Tainted:  5.6.0-smp-DEV #1
Hardware name: ...
Call Trace:
 <IRQ>
 dump_stack+0x57/0x75
 mem_cgroup_sk_alloc+0xe9/0xf0
 sk_clone_lock+0x2a7/0x420
 inet_csk_clone_lock+0x1b/0x110
 tcp_create_openreq_child+0x23/0x3b0
 tcp_v6_syn_recv_sock+0x88/0x730
 tcp_check_req+0x429/0x560
 tcp_v6_rcv+0x72d/0xa40
 ip6_protocol_deliver_rcu+0xc9/0x400
 ip6_input+0x44/0xd0
 ? ip6_protocol_deliver_rcu+0x400/0x400
 ip6_rcv_finish+0x71/0x80
 ipv6_rcv+0x5b/0xe0
 ? ip6_sublist_rcv+0x2e0/0x2e0
 process_backlog+0x108/0x1e0
 net_rx_action+0x26b/0x460
 __do_softirq+0x104/0x2a6
 do_softirq_own_stack+0x2a/0x40
 </IRQ>
 do_softirq.part.19+0x40/0x50
 __local_bh_enable_ip+0x51/0x60
 ip6_finish_output2+0x23d/0x520
 ? ip6table_mangle_hook+0x55/0x160
 __ip6_finish_output+0xa1/0x100
 ip6_finish_output+0x30/0xd0
 ip6_output+0x73/0x120
 ? __ip6_finish_output+0x100/0x100
 ip6_xmit+0x2e3/0x600
 ? ipv6_anycast_cleanup+0x50/0x50
 ? inet6_csk_route_socket+0x136/0x1e0
 ? skb_free_head+0x1e/0x30
 inet6_csk_xmit+0x95/0xf0
 __tcp_transmit_skb+0x5b4/0xb20
 __tcp_send_ack.part.60+0xa3/0x110
 tcp_send_ack+0x1d/0x20
 tcp_rcv_state_process+0xe64/0xe80
 ? tcp_v6_connect+0x5d1/0x5f0
 tcp_v6_do_rcv+0x1b1/0x3f0
 ? tcp_v6_do_rcv+0x1b1/0x3f0
 __release_sock+0x7f/0xd0
 release_sock+0x30/0xa0
 __inet_stream_connect+0x1c3/0x3b0
 ? prepare_to_wait+0xb0/0xb0
 inet_stream_connect+0x3b/0x60
 __sys_connect+0x101/0x120
 ? __sys_getsockopt+0x11b/0x140
 __x64_sys_connect+0x1a/0x20
 do_syscall_64+0x51/0x200
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The stack trace of mem_cgroup_sk_alloc() from IRQ-context:
Fixes: 2d75807383 ("mm: memcontrol: consolidate cgroup socket tracking")
Fixes: d979a39d72 ("cgroup: duplicate cgroup reference when cloning sockets")
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-10 15:33:05 -07:00
Linus Torvalds
e941484541 Merge branch 'for-5.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:

 - cgroup.procs listing related fixes.

   It didn't interlock properly with exiting tasks leaving a short
   window where a cgroup has empty cgroup.procs but still can't be
   removed and misbehaved on short reads.

 - psi_show() crash fix on 32bit ino archs

 - Empty release_agent handling fix

* 'for-5.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup1: don't call release_agent when it is ""
  cgroup: fix psi_show() crash on 32bit ino archs
  cgroup: Iterate tasks that did not finish do_exit()
  cgroup: cgroup_procs_next should increase position index
  cgroup-v1: cgroup_pidlist_next should update position index
2020-03-10 15:05:45 -07:00
Linus Torvalds
2c1aca4bd3 Merge branch 'for-5.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue fixes from Tejun Heo:
 "Workqueue has been incorrectly round-robining per-cpu work items.
  Hillf's patch fixes that.

  The other patch documents memory-ordering properties of workqueue
  operations"

* 'for-5.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: don't use wq_select_unbound_cpu() for bound works
  workqueue: Document (some) memory-ordering properties of {queue,schedule}_work()
2020-03-10 14:48:22 -07:00
Yoshiki Komachi
da6c7faeb1 bpf/btf: Fix BTF verification of enum members in struct/union
btf_enum_check_member() was currently sure to recognize the size of
"enum" type members in struct/union as the size of "int" even if
its size was packed.

This patch fixes BTF enum verification to use the correct size
of member in BPF programs.

Fixes: 179cde8cef ("bpf: btf: Check members of struct/union")
Signed-off-by: Yoshiki Komachi <komachi.yoshiki@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1583825550-18606-2-git-send-email-komachi.yoshiki@gmail.com
2020-03-10 10:00:41 -07:00
Hillf Danton
aa202f1f56 workqueue: don't use wq_select_unbound_cpu() for bound works
wq_select_unbound_cpu() is designed for unbound workqueues only, but
it's wrongly called when using a bound workqueue too.

Fixing this ensures work queued to a bound workqueue with
cpu=WORK_CPU_UNBOUND always runs on the local CPU.

Before, that would happen only if wq_unbound_cpumask happened to include
it (likely almost always the case), or was empty, or we got lucky with
forced round-robin placement.  So restricting
/sys/devices/virtual/workqueue/cpumask to a small subset of a machine's
CPUs would cause some bound work items to run unexpectedly there.

Fixes: ef55718044 ("workqueue: schedule WORK_CPU_UNBOUND work on wq_unbound_cpumask CPUs")
Cc: stable@vger.kernel.org # v4.5+
Signed-off-by: Hillf Danton <hdanton@sina.com>
[dj: massage changelog]
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Tejun Heo <tj@kernel.org>
2020-03-10 10:30:51 -04:00
Andrii Nakryiko
1d8006abaa bpf: Fix cgroup ref leak in cgroup_bpf_inherit on out-of-memory
There is no compensating cgroup_bpf_put() for each ancestor cgroup in
cgroup_bpf_inherit(). If compute_effective_progs returns error, those cgroups
won't be freed ever. Fix it by putting them in cleanup code path.

Fixes: e10360f815 ("bpf: cgroup: prevent out-of-order release of cgroup bpf")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Roman Gushchin <guro@fb.com>
Link: https://lore.kernel.org/bpf/20200309224017.1063297-1-andriin@fb.com
2020-03-09 19:58:54 -07:00
Andrii Nakryiko
62039c30c1 bpf: Initialize storage pointers to NULL to prevent freeing garbage pointer
Local storage array isn't initialized, so if cgroup storage allocation fails
for BPF_CGROUP_STORAGE_SHARED, error handling code will attempt to free
uninitialized pointer for BPF_CGROUP_STORAGE_PERCPU storage type. Avoid this
by always initializing storage pointers to NULLs.

Fixes: 8bad74f984 ("bpf: extend cgroup bpf core to allow multiple cgroup storage types")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200309222756.1018737-1-andriin@fb.com
2020-03-09 19:56:48 -07:00
Christian Brauner
10dab84caf
pid: make ENOMEM return value more obvious
The alloc_pid() codepath used to be simpler. With the introducation of the
ability to choose specific pids in 49cb2fc42c ("fork: extend clone3() to
support setting a PID") it got more complex. It hasn't been super obvious
that ENOMEM is returned when the pid namespace init process/child subreaper
of the pid namespace has died. As can be seen from multiple attempts to
improve this see e.g. [1] and most recently [2].
We regressed returning ENOMEM in [3] and [2] restored it. Let's add a
comment on top explaining that this is historic and documented behavior and
cannot easily be changed.

[1]: 35f71bc0a0 ("fork: report pid reservation failure properly")
[2]: b26ebfe12f ("pid: Fix error return value in some cases")
[3]: 49cb2fc42c ("fork: extend clone3() to support setting a PID")
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-03-09 23:40:05 +01:00
Thomas Gleixner
8d67743653 futex: Unbreak futex hashing
The recent futex inode life time fix changed the ordering of the futex key
union struct members, but forgot to adjust the hash function accordingly,

As a result the hashing omits the leading 64bit and even hashes beyond the
futex key causing a bad hash distribution which led to a ~100% performance
regression.

Hand in the futex key pointer instead of a random struct member and make
the size calculation based of the struct offset.

Fixes: 8019ad13ef ("futex: Fix inode life-time issue")
Reported-by: Rong Chen <rong.a.chen@intel.com>
Decoded-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Rong Chen <rong.a.chen@intel.com>
Link: https://lkml.kernel.org/r/87h7yy90ve.fsf@nanos.tec.linutronix.de
2020-03-09 22:33:09 +01:00
Corey Minyard
b26ebfe12f
pid: Fix error return value in some cases
Recent changes to alloc_pid() allow the pid number to be specified on
the command line.  If set_tid_size is set, then the code scanning the
levels will hard-set retval to -EPERM, overriding it's previous -ENOMEM
value.

After the code scanning the levels, there are error returns that do not
set retval, assuming it is still set to -ENOMEM.

So set retval back to -ENOMEM after scanning the levels.

Fixes: 49cb2fc42c ("fork: extend clone3() to support setting a PID")
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Adrian Reber <areber@redhat.com>
Cc: <stable@vger.kernel.org> # 5.5
Link: https://lore.kernel.org/r/20200306172314.12232-1-minyard@acm.org
[christian.brauner@ubuntu.com: fixup commit message]
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-03-08 14:22:58 +01:00
Linus Torvalds
5dfcc13902 block-5.6-2020-03-07
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Merge tag 'block-5.6-2020-03-07' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Here are a few fixes that should go into this release. This contains:

   - Revert of a bad bcache patch from this merge window

   - Removed unused function (Daniel)

   - Fixup for the blktrace fix from Jan from this release (Cengiz)

   - Fix of deeper level bfqq overwrite in BFQ (Carlo)"

* tag 'block-5.6-2020-03-07' of git://git.kernel.dk/linux-block:
  block, bfq: fix overwrite of bfq_group pointer in bfq_find_set_group()
  blktrace: fix dereference after null check
  Revert "bcache: ignore pending signals when creating gc and allocator thread"
  block: Remove used kblockd_schedule_work_on()
2020-03-07 14:14:38 -06:00
Linus Torvalds
fa883d6afb for-linus-2020-03-07
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Merge tag 'for-linus-2020-03-07' of gitolite.kernel.org:pub/scm/linux/kernel/git/brauner/linux

Pull thread fixes from Christian Brauner:
 "Here are a few hopefully uncontroversial fixes:

   - Use RCU_INIT_POINTER() when initializing rcu protected members in
     task_struct to fix sparse warnings.

   - Add pidfd_fdinfo_test binary to .gitignore file"

* tag 'for-linus-2020-03-07' of gitolite.kernel.org:pub/scm/linux/kernel/git/brauner/linux:
  selftests: pidfd: Add pidfd_fdinfo_test in .gitignore
  exit: Fix Sparse errors and warnings
  fork: Use RCU_INIT_POINTER() instead of rcu_access_pointer()
2020-03-07 08:01:43 -06:00
Peter Zijlstra
8019ad13ef futex: Fix inode life-time issue
As reported by Jann, ihold() does not in fact guarantee inode
persistence. And instead of making it so, replace the usage of inode
pointers with a per boot, machine wide, unique inode identifier.

This sequence number is global, but shared (file backed) futexes are
rare enough that this should not become a performance issue.

Reported-by: Jann Horn <jannh@google.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2020-03-06 11:06:15 +01:00
Martin KaFai Lau
849b4d9458 bpf: Do not allow map_freeze in struct_ops map
struct_ops map cannot support map_freeze.  Otherwise, a struct_ops
cannot be unregistered from the subsystem.

Fixes: 85d33df357 ("bpf: Introduce BPF_MAP_TYPE_STRUCT_OPS")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200305013454.535397-1-kafai@fb.com
2020-03-05 14:15:49 -08:00
Martin KaFai Lau
8e5290e710 bpf: Return better error value in delete_elem for struct_ops map
The current always succeed behavior in bpf_struct_ops_map_delete_elem()
is not ideal for userspace tool.  It can be improved to return proper
error value.

If it is in TOBEFREE, it means unregistration has been already done
before but it is in progress and waiting for the subsystem to clear
the refcnt to zero, so -EINPROGRESS.

If it is INIT, it means the struct_ops has not been registered yet,
so -ENOENT.

Fixes: 85d33df357 ("bpf: Introduce BPF_MAP_TYPE_STRUCT_OPS")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200305013447.535326-1-kafai@fb.com
2020-03-05 14:15:48 -08:00
Yonghong Song
1bc7896e9e bpf: Fix deadlock with rq_lock in bpf_send_signal()
When experimenting with bpf_send_signal() helper in our production
environment (5.2 based), we experienced a deadlock in NMI mode:
   #5 [ffffc9002219f770] queued_spin_lock_slowpath at ffffffff8110be24
   #6 [ffffc9002219f770] _raw_spin_lock_irqsave at ffffffff81a43012
   #7 [ffffc9002219f780] try_to_wake_up at ffffffff810e7ecd
   #8 [ffffc9002219f7e0] signal_wake_up_state at ffffffff810c7b55
   #9 [ffffc9002219f7f0] __send_signal at ffffffff810c8602
  #10 [ffffc9002219f830] do_send_sig_info at ffffffff810ca31a
  #11 [ffffc9002219f868] bpf_send_signal at ffffffff8119d227
  #12 [ffffc9002219f988] bpf_overflow_handler at ffffffff811d4140
  #13 [ffffc9002219f9e0] __perf_event_overflow at ffffffff811d68cf
  #14 [ffffc9002219fa10] perf_swevent_overflow at ffffffff811d6a09
  #15 [ffffc9002219fa38] ___perf_sw_event at ffffffff811e0f47
  #16 [ffffc9002219fc30] __schedule at ffffffff81a3e04d
  #17 [ffffc9002219fc90] schedule at ffffffff81a3e219
  #18 [ffffc9002219fca0] futex_wait_queue_me at ffffffff8113d1b9
  #19 [ffffc9002219fcd8] futex_wait at ffffffff8113e529
  #20 [ffffc9002219fdf0] do_futex at ffffffff8113ffbc
  #21 [ffffc9002219fec0] __x64_sys_futex at ffffffff81140d1c
  #22 [ffffc9002219ff38] do_syscall_64 at ffffffff81002602
  #23 [ffffc9002219ff50] entry_SYSCALL_64_after_hwframe at ffffffff81c00068

The above call stack is actually very similar to an issue
reported by Commit eac9153f2b ("bpf/stackmap: Fix deadlock with
rq_lock in bpf_get_stack()") by Song Liu. The only difference is
bpf_send_signal() helper instead of bpf_get_stack() helper.

The above deadlock is triggered with a perf_sw_event.
Similar to Commit eac9153f2b, the below almost identical reproducer
used tracepoint point sched/sched_switch so the issue can be easily caught.
  /* stress_test.c */
  #include <stdio.h>
  #include <stdlib.h>
  #include <sys/mman.h>
  #include <pthread.h>
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <fcntl.h>

  #define THREAD_COUNT 1000
  char *filename;
  void *worker(void *p)
  {
        void *ptr;
        int fd;
        char *pptr;

        fd = open(filename, O_RDONLY);
        if (fd < 0)
                return NULL;
        while (1) {
                struct timespec ts = {0, 1000 + rand() % 2000};

                ptr = mmap(NULL, 4096 * 64, PROT_READ, MAP_PRIVATE, fd, 0);
                usleep(1);
                if (ptr == MAP_FAILED) {
                        printf("failed to mmap\n");
                        break;
                }
                munmap(ptr, 4096 * 64);
                usleep(1);
                pptr = malloc(1);
                usleep(1);
                pptr[0] = 1;
                usleep(1);
                free(pptr);
                usleep(1);
                nanosleep(&ts, NULL);
        }
        close(fd);
        return NULL;
  }

  int main(int argc, char *argv[])
  {
        void *ptr;
        int i;
        pthread_t threads[THREAD_COUNT];

        if (argc < 2)
                return 0;

        filename = argv[1];

        for (i = 0; i < THREAD_COUNT; i++) {
                if (pthread_create(threads + i, NULL, worker, NULL)) {
                        fprintf(stderr, "Error creating thread\n");
                        return 0;
                }
        }

        for (i = 0; i < THREAD_COUNT; i++)
                pthread_join(threads[i], NULL);
        return 0;
  }
and the following command:
  1. run `stress_test /bin/ls` in one windown
  2. hack bcc trace.py with the following change:
     --- a/tools/trace.py
     +++ b/tools/trace.py
     @@ -513,6 +513,7 @@ BPF_PERF_OUTPUT(%s);
              __data.tgid = __tgid;
              __data.pid = __pid;
              bpf_get_current_comm(&__data.comm, sizeof(__data.comm));
     +        bpf_send_signal(10);
      %s
      %s
              %s.perf_submit(%s, &__data, sizeof(__data));
  3. in a different window run
     ./trace.py -p $(pidof stress_test) t:sched:sched_switch

The deadlock can be reproduced in our production system.

Similar to Song's fix, the fix is to delay sending signal if
irqs is disabled to avoid deadlocks involving with rq_lock.
With this change, my above stress-test in our production system
won't cause deadlock any more.

I also implemented a scale-down version of reproducer in the
selftest (a subsequent commit). With latest bpf-next,
it complains for the following potential deadlock.
  [   32.832450] -> #1 (&p->pi_lock){-.-.}:
  [   32.833100]        _raw_spin_lock_irqsave+0x44/0x80
  [   32.833696]        task_rq_lock+0x2c/0xa0
  [   32.834182]        task_sched_runtime+0x59/0xd0
  [   32.834721]        thread_group_cputime+0x250/0x270
  [   32.835304]        thread_group_cputime_adjusted+0x2e/0x70
  [   32.835959]        do_task_stat+0x8a7/0xb80
  [   32.836461]        proc_single_show+0x51/0xb0
  ...
  [   32.839512] -> #0 (&(&sighand->siglock)->rlock){....}:
  [   32.840275]        __lock_acquire+0x1358/0x1a20
  [   32.840826]        lock_acquire+0xc7/0x1d0
  [   32.841309]        _raw_spin_lock_irqsave+0x44/0x80
  [   32.841916]        __lock_task_sighand+0x79/0x160
  [   32.842465]        do_send_sig_info+0x35/0x90
  [   32.842977]        bpf_send_signal+0xa/0x10
  [   32.843464]        bpf_prog_bc13ed9e4d3163e3_send_signal_tp_sched+0x465/0x1000
  [   32.844301]        trace_call_bpf+0x115/0x270
  [   32.844809]        perf_trace_run_bpf_submit+0x4a/0xc0
  [   32.845411]        perf_trace_sched_switch+0x10f/0x180
  [   32.846014]        __schedule+0x45d/0x880
  [   32.846483]        schedule+0x5f/0xd0
  ...

  [   32.853148] Chain exists of:
  [   32.853148]   &(&sighand->siglock)->rlock --> &p->pi_lock --> &rq->lock
  [   32.853148]
  [   32.854451]  Possible unsafe locking scenario:
  [   32.854451]
  [   32.855173]        CPU0                    CPU1
  [   32.855745]        ----                    ----
  [   32.856278]   lock(&rq->lock);
  [   32.856671]                                lock(&p->pi_lock);
  [   32.857332]                                lock(&rq->lock);
  [   32.857999]   lock(&(&sighand->siglock)->rlock);

  Deadlock happens on CPU0 when it tries to acquire &sighand->siglock
  but it has been held by CPU1 and CPU1 tries to grab &rq->lock
  and cannot get it.

  This is not exactly the callstack in our production environment,
  but sympotom is similar and both locks are using spin_lock_irqsave()
  to acquire the lock, and both involves rq_lock. The fix to delay
  sending signal when irq is disabled also fixed this issue.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200304191104.2796501-1-yhs@fb.com
2020-03-05 14:02:22 -08:00
Cengiz Can
153031a301 blktrace: fix dereference after null check
There was a recent change in blktrace.c that added a RCU protection to
`q->blk_trace` in order to fix a use-after-free issue during access.

However the change missed an edge case that can lead to dereferencing of
`bt` pointer even when it's NULL:

Coverity static analyzer marked this as a FORWARD_NULL issue with CID
1460458.

```
/kernel/trace/blktrace.c: 1904 in sysfs_blk_trace_attr_store()
1898            ret = 0;
1899            if (bt == NULL)
1900                    ret = blk_trace_setup_queue(q, bdev);
1901
1902            if (ret == 0) {
1903                    if (attr == &dev_attr_act_mask)
>>>     CID 1460458:  Null pointer dereferences  (FORWARD_NULL)
>>>     Dereferencing null pointer "bt".
1904                            bt->act_mask = value;
1905                    else if (attr == &dev_attr_pid)
1906                            bt->pid = value;
1907                    else if (attr == &dev_attr_start_lba)
1908                            bt->start_lba = value;
1909                    else if (attr == &dev_attr_end_lba)
```

Added a reassignment with RCU annotation to fix the issue.

Fixes: c780e86dd4 ("blktrace: Protect q->blk_trace with RCU")
Cc: stable@vger.kernel.org
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Cengiz Can <cengiz@kernel.wtf>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-05 13:42:40 -07:00
Tycho Andersen
2e5383d790 cgroup1: don't call release_agent when it is ""
Older (and maybe current) versions of systemd set release_agent to "" when
shutting down, but do not set notify_on_release to 0.

Since 64e90a8acb ("Introduce STATIC_USERMODEHELPER to mediate
call_usermodehelper()"), we filter out such calls when the user mode helper
path is "". However, when used in conjunction with an actual (i.e. non "")
STATIC_USERMODEHELPER, the path is never "", so the real usermode helper
will be called with argv[0] == "".

Let's avoid this by not invoking the release_agent when it is "".

Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Signed-off-by: Tejun Heo <tj@kernel.org>
2020-03-04 11:53:33 -05:00
Qian Cai
190ecb190a cgroup: fix psi_show() crash on 32bit ino archs
Similar to the commit d749534322 ("cgroup: fix incorrect
WARN_ON_ONCE() in cgroup_setup_root()"), cgroup_id(root_cgrp) does not
equal to 1 on 32bit ino archs which triggers all sorts of issues with
psi_show() on s390x. For example,

 BUG: KASAN: slab-out-of-bounds in collect_percpu_times+0x2d0/
 Read of size 4 at addr 000000001e0ce000 by task read_all/3667
 collect_percpu_times+0x2d0/0x798
 psi_show+0x7c/0x2a8
 seq_read+0x2ac/0x830
 vfs_read+0x92/0x150
 ksys_read+0xe2/0x188
 system_call+0xd8/0x2b4

Fix it by using cgroup_ino().

Fixes: 743210386c ("cgroup: use cgrp->kn->id as the cgroup ID")
Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org # v5.5
2020-03-04 11:15:58 -05:00
Cyril Hrubis
ecc421e05b sys/sysinfo: Respect boottime inside time namespace
The sysinfo() syscall includes uptime in seconds but has no correction for
time namespaces which makes it inconsistent with the /proc/uptime inside of
a time namespace.

Add the missing time namespace adjustment call.

Signed-off-by: Cyril Hrubis <chrubis@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dmitry Safonov <dima@arista.com>
Link: https://lkml.kernel.org/r/20200303150638.7329-1-chrubis@suse.cz
2020-03-03 19:34:32 +01:00
Linus Torvalds
c105df5d86 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fix from Ingo Molnar:
 "Fix a scheduler statistics bug"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Fix statistics for find_idlest_group()
2020-03-02 06:51:43 -06:00
Linus Torvalds
2edc78b9a4 block-5.6-2020-02-28
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Merge tag 'block-5.6-2020-02-28' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:

 - Passthrough insertion fix (Ming)

 - Kill off some unused arguments (John)

 - blktrace RCU fix (Jan)

 - Dead fields removal for null_blk (Dongli)

 - NVMe polled IO fix (Bijan)

* tag 'block-5.6-2020-02-28' of git://git.kernel.dk/linux-block:
  nvme-pci: Hold cq_poll_lock while completing CQEs
  blk-mq: Remove some unused function arguments
  null_blk: remove unused fields in 'nullb_cmd'
  blktrace: Protect q->blk_trace with RCU
  blk-mq: insert passthrough request into hctx->dispatch directly
2020-02-28 11:43:30 -08:00
Linus Torvalds
3642859812 Power management fixes for 5.6-rc4
Fix a recent cpufreq initialization regression (Rafael Wysocki),
 revert a devfreq commit that made incompatible changes and broke
 user land on some systems (Orson Zhai), drop a stale reference to
 a document that has gone away recently (Jonathan Neuschäfer) and
 fix a typo in a hibernation code comment (Alexandre Belloni).
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Merge tag 'pm-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "Fix a recent cpufreq initialization regression (Rafael Wysocki),
  revert a devfreq commit that made incompatible changes and broke user
  land on some systems (Orson Zhai), drop a stale reference to a
  document that has gone away recently (Jonathan Neuschäfer), and fix a
  typo in a hibernation code comment (Alexandre Belloni)"

* tag 'pm-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: Fix policy initialization for internal governor drivers
  Revert "PM / devfreq: Modify the device name as devfreq(X) for sysfs"
  PM / hibernate: fix typo "reserverd_size" -> "reserved_size"
  Documentation: power: Drop reference to interface.rst
2020-02-28 08:49:52 -08:00
Madhuparna Bhowmik
22a34c6fe0
exit: Fix Sparse errors and warnings
This patch fixes the following sparse error:
kernel/exit.c:627:25: error: incompatible types in comparison expression

And the following warning:
kernel/exit.c:626:40: warning: incorrect type in assignment

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
[christian.brauner@ubuntu.com: edit commit message]
Link: https://lore.kernel.org/r/20200130062028.4870-1-madhuparnabhowmik10@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-02-28 13:34:39 +01:00
Madhuparna Bhowmik
0c282b068e
fork: Use RCU_INIT_POINTER() instead of rcu_access_pointer()
Use RCU_INIT_POINTER() instead of rcu_access_pointer() in
copy_sighand().

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
[christian.brauner@ubuntu.com: edit commit message]
Link: https://lore.kernel.org/r/20200127175821.10833-1-madhuparnabhowmik10@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-02-28 13:34:36 +01:00
Rafael J. Wysocki
189c6967fe Merge branches 'pm-sleep' and 'pm-devfreq'
* pm-sleep:
  PM / hibernate: fix typo "reserverd_size" -> "reserved_size"
  Documentation: power: Drop reference to interface.rst

* pm-devfreq:
  Revert "PM / devfreq: Modify the device name as devfreq(X) for sysfs"
2020-02-28 11:00:50 +01:00
Linus Torvalds
ed5fa55918 audit/stable-5.6 PR 20200226
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Merge tag 'audit-pr-20200226' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit

Pull audit fixes from Paul Moore:
 "Two fixes for problems found by syzbot:

   - Moving audit filter structure fields into a union caused some
     problems in the code which populates that filter structure.

     We keep the union (that idea is a good one), but we are fixing the
     code so that it doesn't needlessly set fields in the union and mess
     up the error handling.

   - The audit_receive_msg() function wasn't validating user input as
     well as it should in all cases, we add the necessary checks"

* tag 'audit-pr-20200226' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
  audit: always check the netlink payload length in audit_receive_msg()
  audit: fix error handling in audit_data_to_entry()
2020-02-27 11:01:22 -08:00
Vincent Guittot
289de35984 sched/fair: Fix statistics for find_idlest_group()
sgs->group_weight is not set while gathering statistics in
update_sg_wakeup_stats(). This means that a group can be classified as
fully busy with 0 running tasks if utilization is high enough.

This path is mainly used for fork and exec.

Fixes: 57abff067a ("sched/fair: Rework find_idlest_group()")
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Link: https://lore.kernel.org/r/20200218144534.4564-1-vincent.guittot@linaro.org
2020-02-27 10:08:27 +01:00
Linus Torvalds
91ad64a84e Tracing updates:
Change in API of bootconfig (before it comes live in a release)
   - Have a magic value "BOOTCONFIG" in initrd to know a bootconfig exists
   - Set CONFIG_BOOT_CONFIG to 'n' by default
   - Show error if "bootconfig" on cmdline but not compiled in
   - Prevent redefining the same value
   - Have a way to append values
   - Added a SELECT BLK_DEV_INITRD to fix a build failure
 
  Synthetic event fixes:
   - Switch to raw_smp_processor_id() for recording CPU value in preempt
     section. (No care for what the value actually is)
   - Fix samples always recording u64 values
   - Fix endianess
   - Check number of values matches number of fields
   - Fix a printing bug
 
  Fix of trace_printk() breaking postponed start up tests
 
  Make a function static that is only used in a single file.
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Merge tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing and bootconfig updates:
 "Fixes and changes to bootconfig before it goes live in a release.

  Change in API of bootconfig (before it comes live in a release):
  - Have a magic value "BOOTCONFIG" in initrd to know a bootconfig
    exists
  - Set CONFIG_BOOT_CONFIG to 'n' by default
  - Show error if "bootconfig" on cmdline but not compiled in
  - Prevent redefining the same value
  - Have a way to append values
  - Added a SELECT BLK_DEV_INITRD to fix a build failure

  Synthetic event fixes:
  - Switch to raw_smp_processor_id() for recording CPU value in preempt
    section. (No care for what the value actually is)
  - Fix samples always recording u64 values
  - Fix endianess
  - Check number of values matches number of fields
  - Fix a printing bug

  Fix of trace_printk() breaking postponed start up tests

  Make a function static that is only used in a single file"

* tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  bootconfig: Fix CONFIG_BOOTTIME_TRACING dependency issue
  bootconfig: Add append value operator support
  bootconfig: Prohibit re-defining value on same key
  bootconfig: Print array as multiple commands for legacy command line
  bootconfig: Reject subkey and value on same parent key
  tools/bootconfig: Remove unneeded error message silencer
  bootconfig: Add bootconfig magic word for indicating bootconfig explicitly
  bootconfig: Set CONFIG_BOOT_CONFIG=n by default
  tracing: Clear trace_state when starting trace
  bootconfig: Mark boot_config_checksum() static
  tracing: Disable trace_printk() on post poned tests
  tracing: Have synthetic event test use raw_smp_processor_id()
  tracing: Fix number printing bug in print_synth_event()
  tracing: Check that number of vals matches number of synth event fields
  tracing: Make synth_event trace functions endian-correct
  tracing: Make sure synth_event_trace() example always uses u64
2020-02-26 10:34:42 -08:00
Linus Torvalds
fda31c5029 signal: avoid double atomic counter increments for user accounting
When queueing a signal, we increment both the users count of pending
signals (for RLIMIT_SIGPENDING tracking) and we increment the refcount
of the user struct itself (because we keep a reference to the user in
the signal structure in order to correctly account for it when freeing).

That turns out to be fairly expensive, because both of them are atomic
updates, and particularly under extreme signal handling pressure on big
machines, you can get a lot of cache contention on the user struct.
That can then cause horrid cacheline ping-pong when you do these
multiple accesses.

So change the reference counting to only pin the user for the _first_
pending signal, and to unpin it when the last pending signal is
dequeued.  That means that when a user sees a lot of concurrent signal
queuing - which is the only situation when this matters - the only
atomic access needed is generally the 'sigpending' count update.

This was noticed because of a particularly odd timing artifact on a
dual-socket 96C/192T Cascade Lake platform: when you get into bad
contention, on that machine for some reason seems to be much worse when
the contention happens in the upper 32-byte half of the cacheline.

As a result, the kernel test robot will-it-scale 'signal1' benchmark had
an odd performance regression simply due to random alignment of the
'struct user_struct' (and pointed to a completely unrelated and
apparently nonsensical commit for the regression).

Avoiding the double increments (and decrements on the dequeueing side,
of course) makes for much less contention and hugely improved
performance on that will-it-scale microbenchmark.

Quoting Feng Tang:

 "It makes a big difference, that the performance score is tripled! bump
  from original 17000 to 54000. Also the gap between 5.0-rc6 and
  5.0-rc6+Jiri's patch is reduced to around 2%"

[ The "2% gap" is the odd cacheline placement difference on that
  platform: under the extreme contention case, the effect of which half
  of the cacheline was hot was 5%, so with the reduced contention the
  odd timing artifact is reduced too ]

It does help in the non-contended case too, but is not nearly as
noticeable.

Reported-and-tested-by: Feng Tang <feng.tang@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Philip Li <philip.li@intel.com>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-26 09:54:03 -08:00
Masami Hiramatsu
2910b5aa6f bootconfig: Fix CONFIG_BOOTTIME_TRACING dependency issue
Since commit d8a953ddde ("bootconfig: Set CONFIG_BOOT_CONFIG=n by
default") also changed the CONFIG_BOOTTIME_TRACING to select
CONFIG_BOOT_CONFIG to show the boot-time tracing on the menu,
it introduced wrong dependencies with BLK_DEV_INITRD as below.

WARNING: unmet direct dependencies detected for BOOT_CONFIG
  Depends on [n]: BLK_DEV_INITRD [=n]
  Selected by [y]:
  - BOOTTIME_TRACING [=y] && TRACING_SUPPORT [=y] && FTRACE [=y] && TRACING [=y]

This makes the CONFIG_BOOT_CONFIG selects CONFIG_BLK_DEV_INITRD to
fix this error and make CONFIG_BOOTTIME_TRACING=n by default, so
that both boot-time tracing and boot configuration off but those
appear on the menu list.

Link: http://lkml.kernel.org/r/158264140162.23842.11237423518607465535.stgit@devnote2

Fixes: d8a953ddde ("bootconfig: Set CONFIG_BOOT_CONFIG=n by default")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Compiled-tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-25 19:07:58 -05:00
Jan Kara
c780e86dd4 blktrace: Protect q->blk_trace with RCU
KASAN is reporting that __blk_add_trace() has a use-after-free issue
when accessing q->blk_trace. Indeed the switching of block tracing (and
thus eventual freeing of q->blk_trace) is completely unsynchronized with
the currently running tracing and thus it can happen that the blk_trace
structure is being freed just while __blk_add_trace() works on it.
Protect accesses to q->blk_trace by RCU during tracing and make sure we
wait for the end of RCU grace period when shutting down tracing. Luckily
that is rare enough event that we can afford that. Note that postponing
the freeing of blk_trace to an RCU callback should better be avoided as
it could have unexpected user visible side-effects as debugfs files
would be still existing for a short while block tracing has been shut
down.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=205711
CC: stable@vger.kernel.org
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reported-by: Tristan Madani <tristmd@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-25 08:40:07 -07:00
Paul Moore
7561252892 audit: always check the netlink payload length in audit_receive_msg()
This patch ensures that we always check the netlink payload length
in audit_receive_msg() before we take any action on the payload
itself.

Cc: stable@vger.kernel.org
Reported-by: syzbot+399c44bf1f43b8747403@syzkaller.appspotmail.com
Reported-by: syzbot+e4b12d8d202701f08b6d@syzkaller.appspotmail.com
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-02-24 16:38:57 -05:00