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27412 Commits

Author SHA1 Message Date
David S. Miller
b9f672af14 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-05-17

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

The main changes are:

1) Provide a new BPF helper for doing a FIB and neighbor lookup
   in the kernel tables from an XDP or tc BPF program. The helper
   provides a fast-path for forwarding packets. The API supports
   IPv4, IPv6 and MPLS protocols, but currently IPv4 and IPv6 are
   implemented in this initial work, from David (Ahern).

2) Just a tiny diff but huge feature enabled for nfp driver by
   extending the BPF offload beyond a pure host processing offload.
   Offloaded XDP programs are allowed to set the RX queue index and
   thus opening the door for defining a fully programmable RSS/n-tuple
   filter replacement. Once BPF decided on a queue already, the device
   data-path will skip the conventional RSS processing completely,
   from Jakub.

3) The original sockmap implementation was array based similar to
   devmap. However unlike devmap where an ifindex has a 1:1 mapping
   into the map there are use cases with sockets that need to be
   referenced using longer keys. Hence, sockhash map is added reusing
   as much of the sockmap code as possible, from John.

4) Introduce BTF ID. The ID is allocatd through an IDR similar as
   with BPF maps and progs. It also makes BTF accessible to user
   space via BPF_BTF_GET_FD_BY_ID and adds exposure of the BTF data
   through BPF_OBJ_GET_INFO_BY_FD, from Martin.

5) Enable BPF stackmap with build_id also in NMI context. Due to the
   up_read() of current->mm->mmap_sem build_id cannot be parsed.
   This work defers the up_read() via a per-cpu irq_work so that
   at least limited support can be enabled, from Song.

6) Various BPF JIT follow-up cleanups and fixups after the LD_ABS/LD_IND
   JIT conversion as well as implementation of an optimized 32/64 bit
   immediate load in the arm64 JIT that allows to reduce the number of
   emitted instructions; in case of tested real-world programs they
   were shrinking by three percent, from Daniel.

7) Add ifindex parameter to the libbpf loader in order to enable
   BPF offload support. Right now only iproute2 can load offloaded
   BPF and this will also enable libbpf for direct integration into
   other applications, from David (Beckett).

8) Convert the plain text documentation under Documentation/bpf/ into
   RST format since this is the appropriate standard the kernel is
   moving to for all documentation. Also add an overview README.rst,
   from Jesper.

9) Add __printf verification attribute to the bpf_verifier_vlog()
   helper. Though it uses va_list we can still allow gcc to check
   the format string, from Mathieu.

10) Fix a bash reference in the BPF selftest's Makefile. The '|& ...'
    is a bash 4.0+ feature which is not guaranteed to be available
    when calling out to shell, therefore use a more portable variant,
    from Joe.

11) Fix a 64 bit division in xdp_umem_reg() by using div_u64()
    instead of relying on the gcc built-in, from Björn.

12) Fix a sock hashmap kmalloc warning reported by syzbot when an
    overly large key size is used in hashmap then causing overflows
    in htab->elem_size. Reject bogus attr->key_size early in the
    sock_hash_alloc(), from Yonghong.

13) Ensure in BPF selftests when urandom_read is being linked that
    --build-id is always enabled so that test_stacktrace_build_id[_nmi]
    won't be failing, from Alexei.

14) Add bitsperlong.h as well as errno.h uapi headers into the tools
    header infrastructure which point to one of the arch specific
    uapi headers. This was needed in order to fix a build error on
    some systems for the BPF selftests, from Sirio.

15) Allow for short options to be used in the xdp_monitor BPF sample
    code. And also a bpf.h tools uapi header sync in order to fix a
    selftest build failure. Both from Prashant.

16) More formally clarify the meaning of ID in the direct packet access
    section of the BPF documentation, from Wang.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-16 22:47:11 -04:00
John Fastabend
e23afe5e7c bpf: sockmap, on update propagate errors back to userspace
When an error happens in the update sockmap element logic also pass
the err up to the user.

Fixes: e5cd3abcb3 ("bpf: sockmap, refactor sockmap routines to work with hashmap")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-17 01:48:22 +02:00
Yonghong Song
683d2ac390 bpf: fix sock hashmap kmalloc warning
syzbot reported a kernel warning below:
  WARNING: CPU: 0 PID: 4499 at mm/slab_common.c:996 kmalloc_slab+0x56/0x70 mm/slab_common.c:996
  Kernel panic - not syncing: panic_on_warn set ...

  CPU: 0 PID: 4499 Comm: syz-executor050 Not tainted 4.17.0-rc3+ #9
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
  Call Trace:
   __dump_stack lib/dump_stack.c:77 [inline]
   dump_stack+0x1b9/0x294 lib/dump_stack.c:113
   panic+0x22f/0x4de kernel/panic.c:184
   __warn.cold.8+0x163/0x1b3 kernel/panic.c:536
   report_bug+0x252/0x2d0 lib/bug.c:186
   fixup_bug arch/x86/kernel/traps.c:178 [inline]
   do_error_trap+0x1de/0x490 arch/x86/kernel/traps.c:296
   do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315
   invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:992
  RIP: 0010:kmalloc_slab+0x56/0x70 mm/slab_common.c:996
  RSP: 0018:ffff8801d907fc58 EFLAGS: 00010246
  RAX: 0000000000000000 RBX: ffff8801aeecb280 RCX: ffffffff8185ebd7
  RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000ffffffe1
  RBP: ffff8801d907fc58 R08: ffff8801adb5e1c0 R09: ffffed0035a84700
  R10: ffffed0035a84700 R11: ffff8801ad423803 R12: ffff8801aeecb280
  R13: 00000000fffffff4 R14: ffff8801ad891a00 R15: 00000000014200c0
   __do_kmalloc mm/slab.c:3713 [inline]
   __kmalloc+0x25/0x760 mm/slab.c:3727
   kmalloc include/linux/slab.h:517 [inline]
   map_get_next_key+0x24a/0x640 kernel/bpf/syscall.c:858
   __do_sys_bpf kernel/bpf/syscall.c:2131 [inline]
   __se_sys_bpf kernel/bpf/syscall.c:2096 [inline]
   __x64_sys_bpf+0x354/0x4f0 kernel/bpf/syscall.c:2096
   do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

The test case is against sock hashmap with a key size 0xffffffe1.
Such a large key size will cause the below code in function
sock_hash_alloc() overflowing and produces a smaller elem_size,
hence map creation will be successful.
    htab->elem_size = sizeof(struct htab_elem) +
                      round_up(htab->map.key_size, 8);

Later, when map_get_next_key is called and kernel tries
to allocate the key unsuccessfully, it will issue
the above warning.

Similar to hashtab, ensure the key size is at most
MAX_BPF_STACK for a successful map creation.

Fixes: 8111038444 ("bpf: sockmap, add hash map support")
Reported-by: syzbot+e4566d29080e7f3460ff@syzkaller.appspotmail.com
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-17 00:56:06 +02:00
John Fastabend
8111038444 bpf: sockmap, add hash map support
Sockmap is currently backed by an array and enforces keys to be
four bytes. This works well for many use cases and was originally
modeled after devmap which also uses four bytes keys. However,
this has become limiting in larger use cases where a hash would
be more appropriate. For example users may want to use the 5-tuple
of the socket as the lookup key.

To support this add hash support.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-15 20:41:03 +02:00
John Fastabend
e5cd3abcb3 bpf: sockmap, refactor sockmap routines to work with hashmap
This patch only refactors the existing sockmap code. This will allow
much of the psock initialization code path and bpf helper codes to
work for both sockmap bpf map types that are backed by an array, the
currently supported type, and the new hash backed bpf map type
sockhash.

Most the fallout comes from three changes,

  - Pushing bpf programs into an independent structure so we
    can use it from the htab struct in the next patch.
  - Generalizing helpers to use void *key instead of the hardcoded
    u32.
  - Instead of passing map/key through the metadata we now do
    the lookup inline. This avoids storing the key in the metadata
    which will be useful when keys can be longer than 4 bytes. We
    rename the sk pointers to sk_redir at this point as well to
    avoid any confusion between the current sk pointer and the
    redirect pointer sk_redir.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-15 17:19:59 +02:00
Song Liu
bae77c5eb5 bpf: enable stackmap with build_id in nmi context
Currently, we cannot parse build_id in nmi context because of
up_read(&current->mm->mmap_sem), this makes stackmap with build_id
less useful. This patch enables parsing build_id in nmi by putting
the up_read() call in irq_work. To avoid memory allocation in nmi
context, we use per cpu variable for the irq_work. As a result, only
one irq_work per cpu is allowed. If the irq_work is in-use, we
fallback to only report ips.

Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-14 23:29:45 +02:00
David S. Miller
b2d6cee117 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The bpf syscall and selftests conflicts were trivial
overlapping changes.

The r8169 change involved moving the added mdelay from 'net' into a
different function.

A TLS close bug fix overlapped with the splitting of the TLS state
into separate TX and RX parts.  I just expanded the tests in the bug
fix from "ctx->conf == X" into "ctx->tx_conf == X && ctx->rx_conf
== X".

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-11 20:53:22 -04:00
Linus Torvalds
4bc871984f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Verify lengths of keys provided by the user is AF_KEY, from Kevin
    Easton.

 2) Add device ID for BCM89610 PHY. Thanks to Bhadram Varka.

 3) Add Spectre guards to some ATM code, courtesy of Gustavo A. R.
    Silva.

 4) Fix infinite loop in NSH protocol code. To Eric Dumazet we are most
    grateful for this fix.

 5) Line up /proc/net/netlink headers properly. This fix from YU Bo, we
    do appreciate.

 6) Use after free in TLS code. Once again we are blessed by the
    honorable Eric Dumazet with this fix.

 7) Fix regression in TLS code causing stalls on partial TLS records.
    This fix is bestowed upon us by Andrew Tomt.

 8) Deal with too small MTUs properly in LLC code, another great gift
    from Eric Dumazet.

 9) Handle cached route flushing properly wrt. MTU locking in ipv4, to
    Hangbin Liu we give thanks for this.

10) Fix regression in SO_BINDTODEVIC handling wrt. UDP socket demux.
    Paolo Abeni, he gave us this.

11) Range check coalescing parameters in mlx4 driver, thank you Moshe
    Shemesh.

12) Some ipv6 ICMP error handling fixes in rxrpc, from our good brother
    David Howells.

13) Fix kexec on mlx5 by freeing IRQs in shutdown path. Daniel Juergens,
    you're the best!

14) Don't send bonding RLB updates to invalid MAC addresses. Debabrata
    Benerjee saved us!

15) Uh oh, we were leaking in udp_sendmsg and ping_v4_sendmsg. The ship
    is now water tight, thanks to Andrey Ignatov.

16) IPSEC memory leak in ixgbe from Colin Ian King, man we've got holes
    everywhere!

17) Fix error path in tcf_proto_create, Jiri Pirko what would we do
    without you!

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (92 commits)
  net sched actions: fix refcnt leak in skbmod
  net: sched: fix error path in tcf_proto_create() when modules are not configured
  net sched actions: fix invalid pointer dereferencing if skbedit flags missing
  ixgbe: fix memory leak on ipsec allocation
  ixgbevf: fix ixgbevf_xmit_frame()'s return type
  ixgbe: return error on unsupported SFP module when resetting
  ice: Set rq_last_status when cleaning rq
  ipv4: fix memory leaks in udp_sendmsg, ping_v4_sendmsg
  mlxsw: core: Fix an error handling path in 'mlxsw_core_bus_device_register()'
  bonding: send learning packets for vlans on slave
  bonding: do not allow rlb updates to invalid mac
  net/mlx5e: Err if asked to offload TC match on frag being first
  net/mlx5: E-Switch, Include VF RDMA stats in vport statistics
  net/mlx5: Free IRQs in shutdown path
  rxrpc: Trace UDP transmission failure
  rxrpc: Add a tracepoint to log ICMP/ICMP6 and error messages
  rxrpc: Fix the min security level for kernel calls
  rxrpc: Fix error reception on AF_INET6 sockets
  rxrpc: Fix missing start of call timeout
  qed: fix spelling mistake: "taskelt" -> "tasklet"
  ...
2018-05-11 14:14:46 -07:00
Linus Torvalds
c110a8b792 Working on some new updates to trace filtering, I noticed that the
regex_match_front() test was updated to be limited to the size
 of the pattern instead of the full test string. But as the test string
 is not guaranteed to be nul terminated, it still needs to consider
 the size of the test string.
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Merge tag 'trace-v4.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Working on some new updates to trace filtering, I noticed that the
  regex_match_front() test was updated to be limited to the size of the
  pattern instead of the full test string.

  But as the test string is not guaranteed to be nul terminated, it
  still needs to consider the size of the test string"

* tag 'trace-v4.17-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix regex_match_front() to not over compare the test string
2018-05-11 13:04:35 -07:00
Linus Torvalds
41e3e10823 Power management fixes for 4.17-rc5
- Restore device_may_wakeup() check in pci_enable_wake() removed
    inadvertently during the 4.13 cycle to prevent systems from
    drawing excessive power when suspended or off, among other
    things (Rafael Wysocki).
 
  - Fix pci_dev_run_wake() to properly handle devices that only can
    signal PME# when in the D3cold power state (Kai Heng Feng).
 
  - Fix the schedutil cpufreq governor to avoid using UINT_MAX
    as the new CPU frequency in some cases due to a missing check
    (Rafael Wysocki).
 
  - Remove a stale comment regarding worker kthreads from the
    schedutil cpufreq governor (Juri Lelli).
 
  - Fix a copy-paste mistake in the intel_pstate driver documentation
    (Juri Lelli).
 
  - Fix a typo in the system sleep states documentation (Jonathan
    Neuschäfer).
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Merge tag 'pm-4.17-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix two PCI power management regressions from the 4.13 cycle and
  one cpufreq schedutil governor bug introduced during the 4.12 cycle,
  drop a stale comment from the schedutil code and fix two mistakes in
  docs.

  Specifics:

   - Restore device_may_wakeup() check in pci_enable_wake() removed
     inadvertently during the 4.13 cycle to prevent systems from drawing
     excessive power when suspended or off, among other things (Rafael
     Wysocki).

   - Fix pci_dev_run_wake() to properly handle devices that only can
     signal PME# when in the D3cold power state (Kai Heng Feng).

   - Fix the schedutil cpufreq governor to avoid using UINT_MAX as the
     new CPU frequency in some cases due to a missing check (Rafael
     Wysocki).

   - Remove a stale comment regarding worker kthreads from the schedutil
     cpufreq governor (Juri Lelli).

   - Fix a copy-paste mistake in the intel_pstate driver documentation
     (Juri Lelli).

   - Fix a typo in the system sleep states documentation (Jonathan
     Neuschäfer)"

* tag 'pm-4.17-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PCI / PM: Check device_may_wakeup() in pci_enable_wake()
  PCI / PM: Always check PME wakeup capability for runtime wakeup support
  cpufreq: schedutil: Avoid using invalid next_freq
  cpufreq: schedutil: remove stale comment
  PM: docs: intel_pstate: fix Active Mode w/o HWP paragraph
  PM: docs: sleep-states: Fix a typo ("includig")
2018-05-11 09:49:02 -07:00
Steven Rostedt (VMware)
dc432c3d7f tracing: Fix regex_match_front() to not over compare the test string
The regex match function regex_match_front() in the tracing filter logic,
was fixed to test just the pattern length from testing the entire test
string. That is, it went from strncmp(str, r->pattern, len) to
strcmp(str, r->pattern, r->len).

The issue is that str is not guaranteed to be nul terminated, and if r->len
is greater than the length of str, it can access more memory than is
allocated.

The solution is to add a simple test if (len < r->len) return 0.

Cc: stable@vger.kernel.org
Fixes: 285caad415 ("tracing/filters: Fix MATCH_FRONT_ONLY filter matching")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-11 10:56:42 -04:00
Jann Horn
0a0b987344 compat: fix 4-byte infoleak via uninitialized struct field
Commit 3a4d44b616 ("ntp: Move adjtimex related compat syscalls to
native counterparts") removed the memset() in compat_get_timex().  Since
then, the compat adjtimex syscall can invoke do_adjtimex() with an
uninitialized ->tai.

If do_adjtimex() doesn't write to ->tai (e.g.  because the arguments are
invalid), compat_put_timex() then copies the uninitialized ->tai field
to userspace.

Fix it by adding the memset() back.

Fixes: 3a4d44b616 ("ntp: Move adjtimex related compat syscalls to native counterparts")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-10 17:51:58 -07:00
Jakub Kicinski
0d83003256 bpf: xdp: allow offloads to store into rx_queue_index
It's fairly easy for offloaded XDP programs to select the RX queue
packets go to.  We need a way of expressing this in the software.
Allow write to the rx_queue_index field of struct xdp_md for
device-bound programs.

Skip convert_ctx_access callback entirely for offloads.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-09 18:04:36 +02:00
Martin KaFai Lau
62dab84c81 bpf: btf: Add struct bpf_btf_info
During BPF_OBJ_GET_INFO_BY_FD on a btf_fd, the current bpf_attr's
info.info is directly filled with the BTF binary data.  It is
not extensible.  In this case, we want to add BTF ID.

This patch adds "struct bpf_btf_info" which has the BTF ID as
one of its member.  The BTF binary data itself is exposed through
the "btf" and "btf_size" members.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-09 17:25:13 +02:00
Martin KaFai Lau
78958fca7e bpf: btf: Introduce BTF ID
This patch gives an ID to each loaded BTF.  The ID is allocated by
the idr like the existing prog-id and map-id.

The bpf_put(map->btf) is moved to __bpf_map_put() so that the
userspace can stop seeing the BTF ID ASAP when the last BTF
refcnt is gone.

It also makes BTF accessible from userspace through the
1. new BPF_BTF_GET_FD_BY_ID command.  It is limited to CAP_SYS_ADMIN
   which is inline with the BPF_BTF_LOAD cmd and the existing
   BPF_[MAP|PROG]_GET_FD_BY_ID cmd.
2. new btf_id (and btf_key_id + btf_value_id) in "struct bpf_map_info"

Once the BTF ID handler is accessible from userspace, freeing a BTF
object has to go through a rcu period.  The BPF_BTF_GET_FD_BY_ID cmd
can then be done under a rcu_read_lock() instead of taking
spin_lock.
[Note: A similar rcu usage can be done to the existing
       bpf_prog_get_fd_by_id() in a follow up patch]

When processing the BPF_BTF_GET_FD_BY_ID cmd,
refcount_inc_not_zero() is needed because the BTF object
could be already in the rcu dead row .  btf_get() is
removed since its usage is currently limited to btf.c
alone.  refcount_inc() is used directly instead.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-09 17:25:13 +02:00
Martin KaFai Lau
82e9697250 bpf: btf: Avoid WARN_ON when CONFIG_REFCOUNT_FULL=y
If CONFIG_REFCOUNT_FULL=y, refcount_inc() WARN when refcount is 0.
When creating a new btf, the initial btf->refcnt is 0 and
triggered the following:

[   34.855452] refcount_t: increment on 0; use-after-free.
[   34.856252] WARNING: CPU: 6 PID: 1857 at lib/refcount.c:153 refcount_inc+0x26/0x30
....
[   34.868809] Call Trace:
[   34.869168]  btf_new_fd+0x1af6/0x24d0
[   34.869645]  ? btf_type_seq_show+0x200/0x200
[   34.870212]  ? lock_acquire+0x3b0/0x3b0
[   34.870726]  ? security_capable+0x54/0x90
[   34.871247]  __x64_sys_bpf+0x1b2/0x310
[   34.871761]  ? __ia32_sys_bpf+0x310/0x310
[   34.872285]  ? bad_area_access_error+0x310/0x310
[   34.872894]  do_syscall_64+0x95/0x3f0

This patch uses refcount_set() instead.

Reported-by: Yonghong Song <yhs@fb.com>
Tested-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-09 17:25:13 +02:00
Rafael J. Wysocki
97739501f2 cpufreq: schedutil: Avoid using invalid next_freq
If the next_freq field of struct sugov_policy is set to UINT_MAX,
it shouldn't be used for updating the CPU frequency (this is a
special "invalid" value), but after commit b7eaf1aab9 (cpufreq:
schedutil: Avoid reducing frequency of busy CPUs prematurely) it
may be passed as the new frequency to sugov_update_commit() in
sugov_update_single().

Fix that by adding an extra check for the special UINT_MAX value
of next_freq to sugov_update_single().

Fixes: b7eaf1aab9 (cpufreq: schedutil: Avoid reducing frequency of busy CPUs prematurely)
Reported-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: 4.12+ <stable@vger.kernel.org> # 4.12+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-09 12:21:17 +02:00
Juri Lelli
a744490f12 cpufreq: schedutil: remove stale comment
After commit 794a56ebd9 (sched/cpufreq: Change the worker kthread to
SCHED_DEADLINE) schedutil kthreads are "ignored" for a clock frequency
selection point of view, so the potential corner case for RT tasks is not
possible at all now.

Remove the stale comment mentioning it.

Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-09 12:20:24 +02:00
David S. Miller
01adc4851a Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Minor conflict, a CHECK was placed into an if() statement
in net-next, whilst a newline was added to that CHECK
call in 'net'.  Thanks to Daniel for the merge resolution.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-07 23:35:08 -04:00
Linus Torvalds
fe282c609d Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull clocksource fixes from Thomas Gleixner:
 "The recent addition of the early TSC clocksource breaks on machines
  which have an unstable TSC because in case that TSC is disabled, then
  the clocksource selection logic falls back to the early TSC which is
  obviously bogus.

  That also unearthed a few robustness issues in the clocksource
  derating code which are addressed as well"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource: Rework stale comment
  clocksource: Consistent de-rate when marking unstable
  x86/tsc: Fix mark_tsc_unstable()
  clocksource: Initialize cs->wd_list
  clocksource: Allow clocksource_mark_unstable() on unregistered clocksources
  x86/tsc: Always unregister clocksource_tsc_early
2018-05-06 05:35:23 -10:00
Linus Torvalds
4b293907d3 Some of the files in the tracing directory show file mode 0444
when they are writable by root. To fix the confusion, they should
 be 0644. Note, either case root can still write to them.
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Merge tag 'trace-v4.17-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Some of the files in the tracing directory show file mode 0444 when
  they are writable by root. To fix the confusion, they should be 0644.
  Note, either case root can still write to them.

  Zhengyuan asked why I never applied that patch (the first one is from
  2014!). I simply forgot about it. /me lowers head in shame"

* tag 'trace-v4.17-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix the file mode of stack tracer
  ftrace: Have set_graph_* files have normal file modes
2018-05-04 20:57:28 -10:00
David S. Miller
2ba5622fba Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2018-05-05

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

The main changes are:

1) Sanitize attr->{prog,map}_type from bpf(2) since used as an array index
   to retrieve prog/map specific ops such that we prevent potential out of
   bounds value under speculation, from Mark and Daniel.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-04 19:50:10 -04:00
Daniel Borkmann
e94fa1d931 bpf, xskmap: fix crash in xsk_map_alloc error path handling
If bpf_map_precharge_memlock() did not fail, then we set err to zero.
However, any subsequent failure from either alloc_percpu() or the
bpf_map_area_alloc() will return ERR_PTR(0) which in find_and_alloc_map()
will cause NULL pointer deref.

In devmap we have the convention that we return -EINVAL on page count
overflow, so keep the same logic here and just set err to -ENOMEM
after successful bpf_map_precharge_memlock().

Fixes: fbfc504a24 ("bpf: introduce new bpf AF_XDP map type BPF_MAP_TYPE_XSKMAP")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Björn Töpel <bjorn.topel@intel.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-04 14:55:54 -07:00
Jakub Kicinski
ab7f5bf092 bpf: fix references to free_bpf_prog_info() in comments
Comments in the verifier refer to free_bpf_prog_info() which
seems to have never existed in tree.  Replace it with
free_used_maps().

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-04 23:41:04 +02:00
Jakub Kicinski
f4e3ec0d57 bpf: replace map pointer loads before calling into offloads
Offloads may find host map pointers more useful than map fds.
Map pointers can be used to identify the map, while fds are
only valid within the context of loading process.

Jump to skip_full_check on error in case verifier log overflow
has to be handled (replace_map_fd_with_map_ptr() prints to the
log, driver prep may do that too in the future).

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-04 23:41:03 +02:00
Jakub Kicinski
6cb5fb3891 bpf: export bpf_event_output()
bpf_event_output() is useful for offloads to add events to BPF
event rings, export it.  Note that export is placed near the stub
since tracing is optional and kernel/bpf/core.c is always going
to be built.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-04 23:41:03 +02:00
Jakub Kicinski
630a4d3874 nfp: bpf: record offload neutral maps in the driver
For asynchronous events originating from the device, like perf event
output, we need to be able to make sure that objects being referred
to by the FW message are valid on the host.  FW events can get queued
and reordered.  Even if we had a FW message "barrier" we should still
protect ourselves from bogus FW output.

Add a reverse-mapping hash table and record in it all raw map pointers
FW may refer to.  Only record neutral maps, i.e. perf event arrays.
These are currently the only objects FW can refer to.  Use RCU protection
on the read side, update side is under RTNL.

Since program vs map destruction order is slightly painful for offload
simply take an extra reference on all the recorded maps to make sure
they don't disappear.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-04 23:41:03 +02:00
Jakub Kicinski
0cd3cbed3c bpf: offload: allow offloaded programs to use perf event arrays
BPF_MAP_TYPE_PERF_EVENT_ARRAY is special as far as offload goes.
The map only holds glue to perf ring, not actual data.  Allow
non-offloaded perf event arrays to be used in offloaded programs.
Offload driver can extract the events from HW and put them in
the map for user space to retrieve.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-04 23:41:03 +02:00
David S. Miller
a7b15ab887 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Overlapping changes in selftests Makefile.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-04 09:58:56 -04:00
Jiong Wang
4cb3d99c84 bpf: add faked "ending" subprog
There are quite a few code snippet like the following in verifier:

       subprog_start = 0;
       if (env->subprog_cnt == cur_subprog + 1)
               subprog_end = insn_cnt;
       else
               subprog_end = env->subprog_info[cur_subprog + 1].start;

The reason is there is no marker in subprog_info array to tell the end of
it.

We could resolve this issue by introducing a faked "ending" subprog.
The special "ending" subprog is with "insn_cnt" as start offset, so it is
serving as the end mark whenever we iterate over all subprogs.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-04 11:58:36 +02:00
Jiong Wang
9c8105bd44 bpf: centre subprog information fields
It is better to centre all subprog information fields into one structure.
This structure could later serve as function node in call graph.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-04 11:58:36 +02:00
Jiong Wang
f910cefa32 bpf: unify main prog and subprog
Currently, verifier treat main prog and subprog differently. All subprogs
detected are kept in env->subprog_starts while main prog is not kept there.
Instead, main prog is implicitly defined as the prog start at 0.

There is actually no difference between main prog and subprog, it is better
to unify them, and register all progs detected into env->subprog_starts.

This could also help simplifying some code logic.

Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-04 11:58:35 +02:00
Linus Torvalds
e523a2562a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Various sockmap fixes from John Fastabend (pinned map handling,
    blocking in recvmsg, double page put, error handling during redirect
    failures, etc.)

 2) Fix dead code handling in x86-64 JIT, from Gianluca Borello.

 3) Missing device put in RDS IB code, from Dag Moxnes.

 4) Don't process fast open during repair mode in TCP< from Yuchung
    Cheng.

 5) Move address/port comparison fixes in SCTP, from Xin Long.

 6) Handle add a bond slave's master into a bridge properly, from
    Hangbin Liu.

 7) IPv6 multipath code can operate on unitialized memory due to an
    assumption that the icmp header is in the linear SKB area. Fix from
    Eric Dumazet.

 8) Don't invoke do_tcp_sendpages() recursively via TLS, from Dave
    Watson.

9) Fix memory leaks in x86-64 JIT, from Daniel Borkmann.

10) RDS leaks kernel memory to userspace, from Eric Dumazet.

11) DCCP can invoke a tasklet on a freed socket, take a refcount. Also
    from Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (78 commits)
  dccp: fix tasklet usage
  smc: fix sendpage() call
  net/smc: handle unregistered buffers
  net/smc: call consolidation
  qed: fix spelling mistake: "offloded" -> "offloaded"
  net/mlx5e: fix spelling mistake: "loobpack" -> "loopback"
  tcp: restore autocorking
  rds: do not leak kernel memory to user land
  qmi_wwan: do not steal interfaces from class drivers
  ipv4: fix fnhe usage by non-cached routes
  bpf: sockmap, fix error handling in redirect failures
  bpf: sockmap, zero sg_size on error when buffer is released
  bpf: sockmap, fix scatterlist update on error path in send with apply
  net_sched: fq: take care of throttled flows before reuse
  ipv6: Revert "ipv6: Allow non-gateway ECMP for IPv6"
  bpf, x64: fix memleak when not converging on calls
  bpf, x64: fix memleak when not converging after image
  net/smc: restrict non-blocking connect finish
  8139too: Use disable_irq_nosync() in rtl8139_poll_controller()
  sctp: fix the issue that the cookie-ack with auth can't get processed
  ...
2018-05-03 18:57:03 -10:00
Daniel Borkmann
d0f1a451e3 bpf: use array_index_nospec in find_prog_type
Commit 9ef09e35e5 ("bpf: fix possible spectre-v1 in find_and_alloc_map()")
converted find_and_alloc_map() over to use array_index_nospec() to sanitize
map type that user space passes on map creation, and this patch does an
analogous conversion for progs in find_prog_type() as it's also passed from
user space when loading progs as attr->prog_type.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 19:29:35 -07:00
Daniel Borkmann
e0cea7ce98 bpf: implement ld_abs/ld_ind in native bpf
The main part of this work is to finally allow removal of LD_ABS
and LD_IND from the BPF core by reimplementing them through native
eBPF instead. Both LD_ABS/LD_IND were carried over from cBPF and
keeping them around in native eBPF caused way more trouble than
actually worth it. To just list some of the security issues in
the past:

  * fdfaf64e75 ("x86: bpf_jit: support negative offsets")
  * 35607b02db ("sparc: bpf_jit: fix loads from negative offsets")
  * e0ee9c1215 ("x86: bpf_jit: fix two bugs in eBPF JIT compiler")
  * 07aee94394 ("bpf, sparc: fix usage of wrong reg for load_skb_regs after call")
  * 6d59b7dbf7 ("bpf, s390x: do not reload skb pointers in non-skb context")
  * 87338c8e2c ("bpf, ppc64: do not reload skb pointers in non-skb context")

For programs in native eBPF, LD_ABS/LD_IND are pretty much legacy
these days due to their limitations and more efficient/flexible
alternatives that have been developed over time such as direct
packet access. LD_ABS/LD_IND only cover 1/2/4 byte loads into a
register, the load happens in host endianness and its exception
handling can yield unexpected behavior. The latter is explained
in depth in f6b1b3bf0d ("bpf: fix subprog verifier bypass by
div/mod by 0 exception") with similar cases of exceptions we had.
In native eBPF more recent program types will disable LD_ABS/LD_IND
altogether through may_access_skb() in verifier, and given the
limitations in terms of exception handling, it's also disabled
in programs that use BPF to BPF calls.

In terms of cBPF, the LD_ABS/LD_IND is used in networking programs
to access packet data. It is not used in seccomp-BPF but programs
that use it for socket filtering or reuseport for demuxing with
cBPF. This is mostly relevant for applications that have not yet
migrated to native eBPF.

The main complexity and source of bugs in LD_ABS/LD_IND is coming
from their implementation in the various JITs. Most of them keep
the model around from cBPF times by implementing a fastpath written
in asm. They use typically two from the BPF program hidden CPU
registers for caching the skb's headlen (skb->len - skb->data_len)
and skb->data. Throughout the JIT phase this requires to keep track
whether LD_ABS/LD_IND are used and if so, the two registers need
to be recached each time a BPF helper would change the underlying
packet data in native eBPF case. At least in eBPF case, available
CPU registers are rare and the additional exit path out of the
asm written JIT helper makes it also inflexible since not all
parts of the JITer are in control from plain C. A LD_ABS/LD_IND
implementation in eBPF therefore allows to significantly reduce
the complexity in JITs with comparable performance results for
them, e.g.:

test_bpf             tcpdump port 22             tcpdump complex
x64      - before    15 21 10                    14 19  18
         - after      7 10 10                     7 10  15
arm64    - before    40 91 92                    40 91 151
         - after     51 64 73                    51 62 113

For cBPF we now track any usage of LD_ABS/LD_IND in bpf_convert_filter()
and cache the skb's headlen and data in the cBPF prologue. The
BPF_REG_TMP gets remapped from R8 to R2 since it's mainly just
used as a local temporary variable. This allows to shrink the
image on x86_64 also for seccomp programs slightly since mapping
to %rsi is not an ereg. In callee-saved R8 and R9 we now track
skb data and headlen, respectively. For normal prologue emission
in the JITs this does not add any extra instructions since R8, R9
are pushed to stack in any case from eBPF side. cBPF uses the
convert_bpf_ld_abs() emitter which probes the fast path inline
already and falls back to bpf_skb_load_helper_{8,16,32}() helper
relying on the cached skb data and headlen as well. R8 and R9
never need to be reloaded due to bpf_helper_changes_pkt_data()
since all skb access in cBPF is read-only. Then, for the case
of native eBPF, we use the bpf_gen_ld_abs() emitter, which calls
the bpf_skb_load_helper_{8,16,32}_no_cache() helper unconditionally,
does neither cache skb data and headlen nor has an inlined fast
path. The reason for the latter is that native eBPF does not have
any extra registers available anyway, but even if there were, it
avoids any reload of skb data and headlen in the first place.
Additionally, for the negative offsets, we provide an alternative
bpf_skb_load_bytes_relative() helper in eBPF which operates
similarly as bpf_skb_load_bytes() and allows for more flexibility.
Tested myself on x64, arm64, s390x, from Sandipan on ppc64.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:19 -07:00
Mark Rutland
9ef09e35e5 bpf: fix possible spectre-v1 in find_and_alloc_map()
It's possible for userspace to control attr->map_type. Sanitize it when
using it as an array index to prevent an out-of-bounds value being used
under speculation.

Found by smatch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: netdev@vger.kernel.org
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-04 01:16:11 +02:00
Björn Töpel
fbfc504a24 bpf: introduce new bpf AF_XDP map type BPF_MAP_TYPE_XSKMAP
The xskmap is yet another BPF map, very much inspired by
dev/cpu/sockmap, and is a holder of AF_XDP sockets. A user application
adds AF_XDP sockets into the map, and by using the bpf_redirect_map
helper, an XDP program can redirect XDP frames to an AF_XDP socket.

Note that a socket that is bound to certain ifindex/queue index will
*only* accept XDP frames from that netdev/queue index. If an XDP
program tries to redirect from a netdev/queue index other than what
the socket is bound to, the frame will not be received on the socket.

A socket can reside in multiple maps.

v3: Fixed race and simplified code.
v2: Removed one indirection in map lookup.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:24 -07:00
Zhengyuan Liu
0c5a9acc8b tracing: Fix the file mode of stack tracer
It looks weird that the stack_trace_filter file can be written by root
but shows that it does not have write permission by ll command.

Link: http://lkml.kernel.org/r/1518054113-28096-1-git-send-email-liuzhengyuan@kylinos.cn

Signed-off-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-03 11:58:05 -04:00
Chen LinX
1ce0500d23 ftrace: Have set_graph_* files have normal file modes
The set_graph_function and set_graph_notrace file mode should be 0644
instead of 0444 as they are writeable. Note, the mode appears to be ignored
regardless, but they should at least look sane.

Link: http://lkml.kernel.org/r/1409725869-4501-1-git-send-email-linx.z.chen@intel.com

Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Chen LinX <linx.z.chen@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-03 11:55:31 -04:00
Linus Torvalds
f4ef6a438c Various fixes in tracing:
- Tracepoints should not give warning on OOM failures
 
  - Use special field for function pointer in trace event
 
  - Fix igrab issues in uprobes
 
  - Fixes to the new histogram triggers
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Merge tag 'trace-v4.17-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Various fixes in tracing:

   - Tracepoints should not give warning on OOM failures

   - Use special field for function pointer in trace event

   - Fix igrab issues in uprobes

   - Fixes to the new histogram triggers"

* tag 'trace-v4.17-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracepoint: Do not warn on ENOMEM
  tracing: Add field modifier parsing hist error for hist triggers
  tracing: Add field parsing hist error for hist triggers
  tracing: Restore proper field flag printing when displaying triggers
  tracing: initcall: Ordered comparison of function pointers
  tracing: Remove igrab() iput() call from uprobes.c
  tracing: Fix bad use of igrab in trace_uprobe.c
2018-05-02 17:38:37 -10:00
John Fastabend
abaeb096ca bpf: sockmap, fix error handling in redirect failures
When a redirect failure happens we release the buffers in-flight
without calling a sk_mem_uncharge(), the uncharge is called before
dropping the sock lock for the redirecte, however we missed updating
the ring start index. When no apply actions are in progress this
is OK because we uncharge the entire buffer before the redirect.
But, when we have apply logic running its possible that only a
portion of the buffer is being redirected. In this case we only
do memory accounting for the buffer slice being redirected and
expect to be able to loop over the BPF program again and/or if
a sock is closed uncharge the memory at sock destruct time.

With an invalid start index however the program logic looks at
the start pointer index, checks the length, and when seeing the
length is zero (from the initial release and failure to update
the pointer) aborts without uncharging/releasing the remaining
memory.

The fix for this is simply to update the start index. To avoid
fixing this error in two locations we do a small refactor and
remove one case where it is open-coded. Then fix it in the
single function.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-02 15:30:45 -07:00
John Fastabend
fec51d40ea bpf: sockmap, zero sg_size on error when buffer is released
When an error occurs during a redirect we have two cases that need
to be handled (i) we have a cork'ed buffer (ii) we have a normal
sendmsg buffer.

In the cork'ed buffer case we don't currently support recovering from
errors in a redirect action. So the buffer is released and the error
should _not_ be pushed back to the caller of sendmsg/sendpage. The
rationale here is the user will get an error that relates to old
data that may have been sent by some arbitrary thread on that sock.
Instead we simple consume the data and tell the user that the data
has been consumed. We may add proper error recovery in the future.
However, this patch fixes a bug where the bytes outstanding counter
sg_size was not zeroed. This could result in a case where if the user
has both a cork'ed action and apply action in progress we may
incorrectly call into the BPF program when the user expected an
old verdict to be applied via the apply action. I don't have a use
case where using apply and cork at the same time is valid but we
never explicitly reject it because it should work fine. This patch
ensures the sg_size is zeroed so we don't have this case.

In the normal sendmsg buffer case (no cork data) we also do not
zero sg_size. Again this can confuse the apply logic when the logic
calls into the BPF program when the BPF programmer expected the old
verdict to remain. So ensure we set sg_size to zero here as well. And
additionally to keep the psock state in-sync with the sk_msg_buff
release all the memory as well. Previously we did this before
returning to the user but this left a gap where psock and sk_msg_buff
states were out of sync which seems fragile. No additional overhead
is taken here except for a call to check the length and realize its
already been freed. This is in the error path as well so in my
opinion lets have robust code over optimized error paths.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-02 15:30:45 -07:00
John Fastabend
3cc9a472d6 bpf: sockmap, fix scatterlist update on error path in send with apply
When the call to do_tcp_sendpage() fails to send the complete block
requested we either retry if only a partial send was completed or
abort if we receive a error less than or equal to zero. Before
returning though we must update the scatterlist length/offset to
account for any partial send completed.

Before this patch we did this at the end of the retry loop, but
this was buggy when used while applying a verdict to fewer bytes
than in the scatterlist. When the scatterlist length was being set
we forgot to account for the apply logic reducing the size variable.
So the result was we chopped off some bytes in the scatterlist without
doing proper cleanup on them. This results in a WARNING when the
sock is tore down because the bytes have previously been charged to
the socket but are never uncharged.

The simple fix is to simply do the accounting inside the retry loop
subtracting from the absolute scatterlist values rather than trying
to accumulate the totals and subtract at the end.

Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-02 15:30:44 -07:00
Peter Zijlstra
7dba33c634 clocksource: Rework stale comment
AFAICS the hotplug code no longer uses this function.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: len.brown@intel.com
Cc: rjw@rjwysocki.net
Cc: diego.viola@gmail.com
Cc: rui.zhang@intel.com
Link: https://lkml.kernel.org/r/20180430100344.656525644@infradead.org
2018-05-02 16:10:41 +02:00
Peter Zijlstra
cd2af07d82 clocksource: Consistent de-rate when marking unstable
When a registered clocksource gets marked unstable the watchdog_kthread
will de-rate and re-select the clocksource. Ensure it also de-rates
when getting called on an unregistered clocksource.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: len.brown@intel.com
Cc: rjw@rjwysocki.net
Cc: diego.viola@gmail.com
Cc: rui.zhang@intel.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180430100344.594904898@infradead.org
2018-05-02 16:10:41 +02:00
Peter Zijlstra
5b9e886a4a clocksource: Initialize cs->wd_list
A number of places relies on list_empty(&cs->wd_list), however the
list_head does not get initialized. Do so upon registration, such that
thereafter it is possible to rely on list_empty() correctly reflecting
the list membership status.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Diego Viola <diego.viola@gmail.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: stable@vger.kernel.org
Cc: len.brown@intel.com
Cc: rjw@rjwysocki.net
Cc: rui.zhang@intel.com
Link: https://lkml.kernel.org/r/20180430100344.472662715@infradead.org
2018-05-02 16:10:40 +02:00
Peter Zijlstra
2aae7bcfa4 clocksource: Allow clocksource_mark_unstable() on unregistered clocksources
Because of how the code flips between tsc-early and tsc clocksources
it might need to mark one or both unstable. The current code in
mark_tsc_unstable() only worked because previously it registered the
tsc clocksource once and then never touched it.

Since it now unregisters the tsc-early clocksource, it needs to know
if a clocksource got unregistered and the current cs->mult test
doesn't work for that. Instead use list_empty(&cs->list) to test for
registration.

Furthermore, since clocksource_mark_unstable() needs to place the cs
on the wd_list, it links the cs->list and cs->wd_list serialization.
It must not see a clocsource registered (!empty cs->list) but already
past dequeue_watchdog(). So place {en,de}queue{,_watchdog}() under the
same lock.

Provided cs->list is initialized to empty, this then allows us to
unconditionally use clocksource_mark_unstable(), regardless of the
registration state.

Fixes: aa83c45762 ("x86/tsc: Introduce early tsc clocksource")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Diego Viola <diego.viola@gmail.com>
Cc: len.brown@intel.com
Cc: rjw@rjwysocki.net
Cc: diego.viola@gmail.com
Cc: rui.zhang@intel.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180502135312.GS12217@hirez.programming.kicks-ass.net
2018-05-02 16:10:40 +02:00
Mathieu Desnoyers
d66a270be3 tracepoint: Do not warn on ENOMEM
Tracepoint should only warn when a kernel API user does not respect the
required preconditions (e.g. same tracepoint enabled twice, or called
to remove a tracepoint that does not exist).

Silence warning in out-of-memory conditions, given that the error is
returned to the caller.

This ensures that out-of-memory error-injection testing does not trigger
warnings in tracepoint.c, which were seen by syzbot.

Link: https://lkml.kernel.org/r/001a114465e241a8720567419a72@google.com
Link: https://lkml.kernel.org/r/001a1140e0de15fc910567464190@google.com
Link: http://lkml.kernel.org/r/20180315124424.32319-1-mathieu.desnoyers@efficios.com

CC: Peter Zijlstra <peterz@infradead.org>
CC: Jiri Olsa <jolsa@redhat.com>
CC: Arnaldo Carvalho de Melo <acme@kernel.org>
CC: Alexander Shishkin <alexander.shishkin@linux.intel.com>
CC: Namhyung Kim <namhyung@kernel.org>
CC: stable@vger.kernel.org
Fixes: de7b297390 ("tracepoint: Use struct pointer instead of name hash for reg/unreg tracepoints")
Reported-by: syzbot+9c0d616860575a73166a@syzkaller.appspotmail.com
Reported-by: syzbot+4e9ae7fa46233396f64d@syzkaller.appspotmail.com
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-30 12:09:56 -04:00
Alexei Starovoitov
4d220ed0f8 bpf: remove tracepoints from bpf core
tracepoints to bpf core were added as a way to provide introspection
to bpf programs and maps, but after some time it became clear that
this approach is inadequate, so prog_id, map_id and corresponding
get_next_id, get_fd_by_id, get_info_by_fd, prog_query APIs were
introduced and fully adopted by bpftool and other applications.
The tracepoints in bpf core started to rot and causing syzbot warnings:
WARNING: CPU: 0 PID: 3008 at kernel/trace/trace_event_perf.c:274
Kernel panic - not syncing: panic_on_warn set ...
perf_trace_bpf_map_keyval+0x260/0xbd0 include/trace/events/bpf.h:228
trace_bpf_map_update_elem include/trace/events/bpf.h:274 [inline]
map_update_elem kernel/bpf/syscall.c:597 [inline]
SYSC_bpf kernel/bpf/syscall.c:1478 [inline]
Hence this patch deletes tracepoints in bpf core.

Reported-by: Eric Biggers <ebiggers3@gmail.com>
Reported-by: syzbot <bot+a9dbb3c3e64b62536a4bc5ee7bbd4ca627566188@syzkaller.appspotmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-30 10:55:56 +02:00
Teng Qin
7ef3771205 bpf: Allow bpf_current_task_under_cgroup in interrupt
Currently, the bpf_current_task_under_cgroup helper has a check where if
the BPF program is running in_interrupt(), it will return -EINVAL. This
prevents the helper to be used in many useful scenarios, particularly
BPF programs attached to Perf Events.

This commit removes the check. Tested a few NMI (Perf Event) and some
softirq context, the helper returns the correct result.

Signed-off-by: Teng Qin <qinteng@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-29 09:18:04 -07:00