The 'duration' variable is referenced in the CHECK() macro, and there are
some uses of the macro before 'duration' is set.  The clang compiler
(validly) complains about this.

Sample error:

.../selftests/bpf/prog_tests/fexit_test.c:23:6: warning: variable 'duration' is uninitialized when used here [-Wuninitialized]
        if (CHECK(err, "prog_load sched cls", "err %d errno %d\n", err, errno))
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.../selftests/bpf/test_progs.h:134:25: note: expanded from macro 'CHECK'
        if (CHECK(err, "prog_load sched cls", "err %d errno %d\n", err, errno))
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
        _CHECK(condition, tag, duration, format)
                               ^~~~~~~~
Signed-off-by: John Sperbeck <jsperbeck@google.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200123235144.93610-1-sdf@google.com

head is traversed using hlist_for_each_entry_rcu outside an RCU
read-side critical section but under the protection of dtab->index_lock.

Hence, add corresponding lockdep expression to silence false-positive
lockdep warnings, and harden RCU lists.

Fixes: 6f9d451a ("xdp: Add devmap_hash map type for looking up devices by hashed index")
Signed-off-by: Amol Grover <frextrite@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20200123120437.26506-1-frextrite@gmail.com

Convert suitable drivers to use new helper phy_do_ioctl_running.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Acked-by: Timur Tabi <timur@kernel.org>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Alexei Starovoitov says:

====================
pull-request: bpf-next 2020-01-22

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

We've added 92 non-merge commits during the last 16 day(s) which contain
a total of 320 files changed, 7532 insertions(+), 1448 deletions(-).

The main changes are:

1) function by function verification and program extensions from Alexei.

2) massive cleanup of selftests/bpf from Toke and Andrii.

3) batched bpf map operations from Brian and Yonghong.

4) tcp congestion control in bpf from Martin.

5) bulking for non-map xdp_redirect form Toke.

6) bpf_send_signal_thread helper from Yonghong.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Martin KaFai Lau says:

====================
This set adds bpf_cubic.c example.  It was separated from the
earlier BPF STRUCT_OPS series.  Some highlights since the
last post:

1. It is based on EricD recent fixes to the kernel tcp_cubic. [1]
2. The bpf jiffies reading helper is inlined by the verifier.
   Different from the earlier version, it only reads jiffies alone
   and does not do usecs/jiffies conversion.
3. The bpf .kconfig map is used to read CONFIG_HZ.

[1]: https://patchwork.ozlabs.org/cover/1215066/

v3:
- Remove __weak from CONFIG_HZ in patch 3. (Andrii)

v2:
- Move inlining to fixup_bpf_calls() in patch 1. (Daniel)
- It is inlined for 64 BITS_PER_LONG and jit_requested
  as the map_gen_lookup().  Other cases could be
  considered together with map_gen_lookup() if needed.
- Use usec resolution in bictcp_update() calculation in patch 3.
  usecs_to_jiffies() is then removed().  (Eric)
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

This patch adds a bpf_cubic example.  Some highlights:
1. CONFIG_HZ .kconfig map is used.
2. In bictcp_update(), calculation is changed to use usec
   resolution (i.e. USEC_PER_JIFFY) instead of using jiffies.
   Thus, usecs_to_jiffies() is not used in the bpf_cubic.c.
3. In bitctcp_update() [under tcp_friendliness], the original
   "while (ca->ack_cnt > delta)" loop is changed to the equivalent
   "ca->ack_cnt / delta" operation.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200122233658.903774-1-kafai@fb.com

This patch sync uapi bpf.h to tools/.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200122233652.903348-1-kafai@fb.com

This patch adds a helper to read the 64bit jiffies.  It will be used
in a later patch to implement the bpf_cubic.c.

The helper is inlined for jit_requested and 64 BITS_PER_LONG
as the map_gen_lookup().  Other cases could be considered together
with map_gen_lookup() if needed.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200122233646.903260-1-kafai@fb.com

Alexei Starovoitov says:

====================
The last few month BPF community has been discussing an approach to call
chaining, since exiting bpt_tail_call() mechanism used in production XDP
programs has plenty of downsides. The outcome of these discussion was a
conclusion to implement dynamic re-linking of BPF programs. Where rootlet XDP
program attached to a netdevice can programmatically define a policy of
execution of other XDP programs. Such rootlet would be compiled as normal XDP
program and provide a number of placeholder global functions which later can be
replaced with future XDP programs. BPF trampoline, function by function
verification were building blocks towards that goal. The patch 1 is a final
building block. It introduces dynamic program extensions. A number of
improvements like more flexible function by function verification and better
libbpf api will be implemented in future patches.

v1->v2:
- addressed Andrii's comments
- rebase
====================
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

Add program extension tests that build on top of fexit_bpf2bpf tests.
Replace three global functions in previously loaded test_pkt_access.c program
with three new implementations:
int get_skb_len(struct __sk_buff *skb);
int get_constant(long val);
int get_skb_ifindex(int val, struct __sk_buff *skb, int var);
New function return the same results as original only if arguments match.

new_get_skb_ifindex() demonstrates that 'skb' argument doesn't have to be first
and only argument of BPF program. All normal skb based accesses are available.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20200121005348.2769920-4-ast@kernel.org

Add minimal support for program extensions. bpf_object_open_opts() needs to be
called with attach_prog_fd = target_prog_fd and BPF program extension needs to
have in .c file section definition like SEC("freplace/func_to_be_replaced").
libbpf will search for "func_to_be_replaced" in the target_prog_fd's BTF and
will pass it in attach_btf_id to the kernel. This approach works for tests, but
more compex use case may need to request function name (and attach_btf_id that
kernel sees) to be more dynamic. Such API will be added in future patches.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20200121005348.2769920-3-ast@kernel.org

Introduce dynamic program extensions. The users can load additional BPF
functions and replace global functions in previously loaded BPF programs while
these programs are executing.

Global functions are verified individually by the verifier based on their types only.
Hence the global function in the new program which types match older function can
safely replace that corresponding function.

This new function/program is called 'an extension' of old program. At load time
the verifier uses (attach_prog_fd, attach_btf_id) pair to identify the function
to be replaced. The BPF program type is derived from the target program into
extension program. Technically bpf_verifier_ops is copied from target program.
The BPF_PROG_TYPE_EXT program type is a placeholder. It has empty verifier_ops.
The extension program can call the same bpf helper functions as target program.
Single BPF_PROG_TYPE_EXT type is used to extend XDP, SKB and all other program
types. The verifier allows only one level of replacement. Meaning that the
extension program cannot recursively extend an extension. That also means that
the maximum stack size is increasing from 512 to 1024 bytes and maximum
function nesting level from 8 to 16. The programs don't always consume that
much. The stack usage is determined by the number of on-stack variables used by
the program. The verifier could have enforced 512 limit for combined original
plus extension program, but it makes for difficult user experience. The main
use case for extensions is to provide generic mechanism to plug external
programs into policy program or function call chaining.

BPF trampoline is used to track both fentry/fexit and program extensions
because both are using the same nop slot at the beginning of every BPF
function. Attaching fentry/fexit to a function that was replaced is not
allowed. The opposite is true as well. Replacing a function that currently
being analyzed with fentry/fexit is not allowed. The executable page allocated
by BPF trampoline is not used by program extensions. This inefficiency will be
optimized in future patches.

Function by function verification of global function supports scalars and
pointer to context only. Hence program extensions are supported for such class
of global functions only. In the future the verifier will be extended with
support to pointers to structures, arrays with sizes, etc.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20200121005348.2769920-2-ast@kernel.org

The first batch of driver conversions missed a few cases where we can
use phy_do_ioctl too.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

When trying to compile with CONFIG_DEBUG_INFO_BTF enabled, I got this
error:

    % make -s
    Failed to generate BTF for vmlinux
    Try to disable CONFIG_DEBUG_INFO_BTF
    make[3]: *** [vmlinux] Error 1

Compiling again without -s shows the true error (that pahole is
missing), but since this is fatal, we should show the error
unconditionally on stderr as well, not silence it using the `info`
function. With this patch:

    % make -s
    BTF: .tmp_vmlinux.btf: pahole (pahole) is not available
    Failed to generate BTF for vmlinux
    Try to disable CONFIG_DEBUG_INFO_BTF
    make[3]: *** [vmlinux] Error 1
Signed-off-by: Chris Down <chris@chrisdown.name>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200122000110.GA310073@chrisdown.name

During cross-compilation, it was discovered that LDFLAGS and
LDLIBS were not being used while building binaries, leading
to defaults which were not necessarily correct.

OpenEmbedded reported this kind of problem:

  ERROR: QA Issue: No GNU_HASH in the ELF binary [...], didn't pass LDFLAGS?
Signed-off-by: Daniel Díaz <daniel.diaz@linaro.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>

Restore the 'if (env->cur_state)' check that was incorrectly removed during
code move. Under memory pressure env->cur_state can be freed and zeroed inside
do_check(). Hence the check is necessary.

Fixes: 51c39bb1 ("bpf: Introduce function-by-function verification")
Reported-by: syzbot+b296579ba5015704d9fa@syzkaller.appspotmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200122024138.3385590-1-ast@kernel.org

Though the second half of trampoline page is unused a task could be
preempted in the middle of the first half of trampoline and two
updates to trampoline would change the code from underneath the
preempted task. Hence wait for tasks to voluntarily schedule or go
to userspace. Add similar wait before freeing the trampoline.

Fixes: fec56f58 ("bpf: Introduce BPF trampoline")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/bpf/20200121032231.3292185-1-ast@kernel.org

XDP sockets use the default implementation of struct sock's
sk_data_ready callback, which is sock_def_readable(). This function
is called in the XDP socket fast-path, and involves a retpoline. By
letting sock_def_readable() have external linkage, and being called
directly, the retpoline can be avoided.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200120092917.13949-1-bjorn.topel@gmail.com

kernel/bpf/inode.c misuses kern_path...() - it's much simpler (and
more efficient, on top of that) to use user_path...() counterparts
rather than bothering with doing getname() manually.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200120232858.GF8904@ZenIV.linux.org.uk

Steffen Klassert says:

====================
pull request (net-next): ipsec-next 2020-01-21

1) Add support for TCP encapsulation of IKE and ESP messages,
   as defined by RFC 8229. Patchset from Sabrina Dubroca.

Please note that there is a merge conflict in:

net/unix/af_unix.c

between commit:

3c32da19 ("unix: Show number of pending scm files of receive queue in fdinfo")

from the net-next tree and commit:

b50b0580 ("net: add queue argument to __skb_wait_for_more_packets and __skb_{,try_}recv_datagram")

from the ipsec-next tree.

The conflict can be solved as done in linux-next.

Please pull or let me know if there are problems.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Fixes coccicheck warning:

./drivers/net/ethernet/amd/declance.c:611:14-15:
	WARNING comparing pointer to 0

Replace "skb == 0" with "!skb".
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After commit 079096f1 ("tcp/dccp: install syn_recv requests into ehash table")
the macro isn't used anymore. remove it.
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

It's never used after introduced. So maybe better to remove.
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Arvid Brodin <arvid.brodin@alten.se>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/wan/hdlc_x25.c: In function ‘x25_ioctl’:
drivers/net/wan/hdlc_x25.c:256:7: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
  256 |   if (ifr->ifr_settings.size = 0) {
      |       ^~~
Signed-off-by: David S. Miller <davem@davemloft.net>

Huazhong Tan says:

====================
net: hns3: misc updates for -net-next

This series includes some misc updates for the HNS3 ethernet driver.

[patch 1] adds a limitation for the error log in the
hns3_clean_tx_ring().
[patch 2] adds a check for pfmemalloc flag before reusing pages
since these pages may be used some special case.
[patch 3] assigns a default reset type 'HNAE3_NONE_RESET' to
VF's reset_type after initializing or reset.
[patch 4] unifies macro HCLGE_DFX_REG_TYPE_CNT's definition into
header file.
[patch 5] refines the parameter 'size' of snprintf() in the
hns3_init_module().
[patch 6] rewrites a debug message in hclge_put_vector().
[patch 7~9] adds some cleanups related to coding style.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch removes some unnecessary return value assignments,
some duplicated printing in the caller, refines the judgment
of 0 and uses le16_to_cpu to replace __le16_to_cpu.
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

All kmalloc-based functions print enough information on failures.
So this patch removes the log in hclge_get_dfx_reg() when returns
ENOMEM.
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch deletes some unnecessary blank lines and spaces to clean up
code, and in hclgevf_set_vlan_filter() moves the comment to the front
of hclgevf_send_mbx_msg().
Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When gets vector fails, hclge_put_vector() should print out
the vector instead of vector_id in the log and return the wrong
vector_id to its caller.
Signed-off-by: Yonglong Liu <liuyonglong@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The function snprintf() writes at most size bytes (including the
terminating null byte ('\0') to str. Now, We can guarantee that the
parameter of size is lager than the length of str to be formatting
including its terminating null byte. So it's unnecessary to minus 1
for the input parameter 'size'.
Signed-off-by: Guojia Liao <liaoguojia@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Macro HCLGE_GET_DFX_REG_TYPE_CNT in hclge_dbg_get_dfx_bd_num()
and macro HCLGE_DFX_REG_BD_NUM in hclge_get_dfx_reg_bd_num()
have the same meaning, so just defines HCLGE_GET_DFX_REG_TYPE_CNT
in hclge_main.h.
Signed-off-by: Guojia Liao <liaoguojia@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

reset_type means what kind of reset the driver is handling now,
so after initializing or reset, the reset_type of VF should be
set to HNAE3_NONE_RESET, otherwise, this unknown default value
may be a little misleading when the device is running.
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

HNS3 driver allocates pages for DMA with dev_alloc_pages(), which
calls alloc_pages_node() with the __GFP_MEMALLOC flag. So, in case
of OOM condition, HNS3 can get pages with pfmemalloc flag set.

So do not reuse the pages with pfmemalloc flag set because those
pages are reserved for special cases, such as low memory case.
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The error log printed by netdev_err() in the hns3_clean_tx_ring()
may spam the kernel log.

This patch uses hns3_rl_err() to ratelimit the error log in the
hns3_clean_tx_ring().
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

o call skb_reset_network_header() before hdlc->xmit()
 o change skb proto to HDLC (0x0019) before hdlc->xmit()
 o call dev_queue_xmit_nit() before hdlc->xmit()

This changes make it possible to trace (tcpdump) outgoing layer2
(ETH_P_HDLC) packets

Additionally call skb_reset_network_header() after each skb_push() /
skb_pull().
Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

This enables you to configure mode (DTE/DCE), Modulo, Window, T1, T2, N2 via
sethdlc (which needs to be patched as well).
Signed-off-by: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

The current flags of the SMC_PNET_GET command only allow privileged
users to retrieve entries from the pnet table via netlink. The content
of the pnet table may be useful for all users though, e.g., for
debugging smc connection problems.

This patch removes the GENL_ADMIN_PERM flag so that unprivileged users
can read the pnet table.
Signed-off-by: Hans Wippel <ndev@hwipl.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Heiner Kallweit says:

====================
net: phy: add new version of phy_do_ioctl and convert suitable drivers

We just added phy_do_ioctl, but it turned out that we need another
version of this function that doesn't check whether net_device is
running. So rename phy_do_ioctl to phy_do_ioctl_running and add a
new version of phy_do_ioctl. Eventually convert suitable drivers
to use phy_do_ioctl.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Convert suitable network drivers to use phy_do_ioctl.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add a new version of phy_do_ioctl that doesn't check whether net_device
is running. It will typically be used if suitable drivers attach the
PHY in probe already.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>