linux.git/drivers/net/ppp/ppp_generic.c, branch v5.16

ppp: use the correct function to check if a netdev name is in use

2021-10-08T16:02:35+00:00

A new helper to detect if a net device name is in use was added. Use it
here as the return reference from __dev_get_by_name was discarded.

Signed-off-by: Antoine Tenart 
Signed-off-by: David S. Miller

bpf: Refactor BPF_PROG_RUN into a function

2021-08-16T22:45:07+00:00

Turn BPF_PROG_RUN into a proper always inlined function. No functional and
performance changes are intended, but it makes it much easier to understand
what's going on with how BPF programs are actually get executed. It's more
obvious what types and callbacks are expected. Also extra () around input
parameters can be dropped, as well as `__` variable prefixes intended to avoid
naming collisions, which makes the code simpler to read and write.

This refactoring also highlighted one extra issue. BPF_PROG_RUN is both
a macro and an enum value (BPF_PROG_RUN == BPF_PROG_TEST_RUN). Turning
BPF_PROG_RUN into a function causes naming conflict compilation error. So
rename BPF_PROG_RUN into lower-case bpf_prog_run(), similar to
bpf_prog_run_xdp(), bpf_prog_run_pin_on_cpu(), etc. All existing callers of
BPF_PROG_RUN, the macro, are switched to bpf_prog_run() explicitly.

Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann 
Acked-by: Yonghong Song 
Link: https://lore.kernel.org/bpf/20210815070609.987780-2-andrii@kernel.org

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2021-08-13T13:41:22+00:00

Conflicts:

drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.h
  9e26680733d5 ("bnxt_en: Update firmware call to retrieve TX PTP timestamp")
  9e518f25802c ("bnxt_en: 1PPS functions to configure TSIO pins")
  099fdeda659d ("bnxt_en: Event handler for PPS events")

kernel/bpf/helpers.c
include/linux/bpf-cgroup.h
  a2baf4e8bb0f ("bpf: Fix potentially incorrect results with bpf_get_local_storage()")
  c7603cfa04e7 ("bpf: Add ambient BPF runtime context stored in current")

drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c
  5957cc557dc5 ("net/mlx5: Set all field of mlx5_irq before inserting it to the xarray")
  2d0b41a37679 ("net/mlx5: Refcount mlx5_irq with integer")

MAINTAINERS
  7b637cd52f02 ("MAINTAINERS: fix Microchip CAN BUS Analyzer Tool entry typo")
  7d901a1e878a ("net: phy: add Maxlinear GPY115/21x/24x driver")

Signed-off-by: Jakub Kicinski

ppp: Fix generating ppp unit id when ifname is not specified

2021-08-08T12:08:46+00:00

When registering new ppp interface via PPPIOCNEWUNIT ioctl then kernel has
to choose interface name as this ioctl API does not support specifying it.

Kernel in this case register new interface with name "ppp" where 
is the ppp unit id, which can be obtained via PPPIOCGUNIT ioctl. This
applies also in the case when registering new ppp interface via rtnl
without supplying IFLA_IFNAME.

PPPIOCNEWUNIT ioctl allows to specify own ppp unit id which will kernel
assign to ppp interface, in case this ppp id is not already used by other
ppp interface.

In case user does not specify ppp unit id then kernel choose the first free
ppp unit id. This applies also for case when creating ppp interface via
rtnl method as it does not provide a way for specifying own ppp unit id.

If some network interface (does not have to be ppp) has name "ppp"
with this first free ppp id then PPPIOCNEWUNIT ioctl or rtnl call fails.

And registering new ppp interface is not possible anymore, until interface
which holds conflicting name is renamed. Or when using rtnl method with
custom interface name in IFLA_IFNAME.

As list of allocated / used ppp unit ids is not possible to retrieve from
kernel to userspace, userspace has no idea what happens nor which interface
is doing this conflict.

So change the algorithm how ppp unit id is generated. And choose the first
number which is not neither used as ppp unit id nor in some network
interface with pattern "ppp".

This issue can be simply reproduced by following pppd call when there is no
ppp interface registered and also no interface with name pattern "ppp":

    pppd ifname ppp1 +ipv6 noip noauth nolock local nodetach pty "pppd +ipv6 noip noauth nolock local nodetach notty"

Or by creating the one ppp interface (which gets assigned ppp unit id 0),
renaming it to "ppp1" and then trying to create a new ppp interface (which
will always fails as next free ppp unit id is 1, but network interface with
name "ppp1" exists).

This patch fixes above described issue by generating new and new ppp unit
id until some non-conflicting id with network interfaces is generated.

Signed-off-by: Pali Rohár 
Cc: stable@vger.kernel.org
Signed-off-by: David S. Miller

ppp: Fix generating ifname when empty IFLA_IFNAME is specified

2021-08-08T12:07:52+00:00

IFLA_IFNAME is nul-term string which means that IFLA_IFNAME buffer can be
larger than length of string which contains.

Function __rtnl_newlink() generates new own ifname if either IFLA_IFNAME
was not specified at all or userspace passed empty nul-term string.

It is expected that if userspace does not specify ifname for new ppp netdev
then kernel generates one in format "ppp" where id matches to the ppp
unit id which can be later obtained by PPPIOCGUNIT ioctl.

And it works in this way if IFLA_IFNAME is not specified at all. But it
does not work when IFLA_IFNAME is specified with empty string.

So fix this logic also for empty IFLA_IFNAME in ppp_nl_newlink() function
and correctly generates ifname based on ppp unit identifier if userspace
did not provided preferred ifname.

Without this patch when IFLA_IFNAME was specified with empty string then
kernel created a new ppp interface in format "ppp" but id did not
match ppp unit id returned by PPPIOCGUNIT ioctl. In this case id was some
number generated by __rtnl_newlink() function.

Signed-off-by: Pali Rohár 
Fixes: bb8082f69138 ("ppp: build ifname using unit identifier for rtnl based devices")
Signed-off-by: David S. Miller

ppp: use ndo_siocdevprivate

2021-07-27T19:11:44+00:00

ppp has a custom statistics interface using SIOCDEVPRIVATE
ioctl commands that works correctly in compat mode.

Convert it to use ndo_siocdevprivate as a cleanup.

Cc: Paul Mackerras 
Cc: linux-ppp@vger.kernel.org
Signed-off-by: Arnd Bergmann 
Signed-off-by: David S. Miller

net: ppp: resolve forwarding path for bridge pppoe devices

2021-03-24T19:48:38+00:00

Pass on the PPPoE session ID, destination hardware address and the real
device.

Signed-off-by: Felix Fietkau 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: David S. Miller

ppp: fix refcount underflow on channel unbridge

2021-01-09T03:21:06+00:00

When setting up a channel bridge, ppp_bridge_channels sets the
pch->bridge field before taking the associated reference on the bridge
file instance.

This opens up a refcount underflow bug if ppp_bridge_channels called
via. iotcl runs concurrently with ppp_unbridge_channels executing via.
file release.

The bug is triggered by ppp_bridge_channels taking the error path
through the 'err_unset' label.  In this scenario, pch->bridge is set,
but the reference on the bridged channel will not be taken because
the function errors out.  If ppp_unbridge_channels observes pch->bridge
before it is unset by the error path, it will erroneously drop the
reference on the bridged channel and cause a refcount underflow.

To avoid this, ensure that ppp_bridge_channels holds a reference on
each channel in advance of setting the bridge pointers.

Signed-off-by: Tom Parkin 
Fixes: 4cf476ced45d ("ppp: add PPPIOCBRIDGECHAN and PPPIOCUNBRIDGECHAN ioctls")
Acked-by: Guillaume Nault 
Link: https://lore.kernel.org/r/20210107181315.3128-1-tparkin@katalix.com
Signed-off-by: Jakub Kicinski

ppp: add PPPIOCBRIDGECHAN and PPPIOCUNBRIDGECHAN ioctls

2020-12-10T21:57:36+00:00

This new ioctl pair allows two ppp channels to be bridged together:
frames arriving in one channel are transmitted in the other channel
and vice versa.

The practical use for this is primarily to support the L2TP Access
Concentrator use-case.  The end-user session is presented as a ppp
channel (typically PPPoE, although it could be e.g. PPPoA, or even PPP
over a serial link) and is switched into a PPPoL2TP session for
transmission to the LNS.  At the LNS the PPP session is terminated in
the ISP's network.

When a PPP channel is bridged to another it takes a reference on the
other's struct ppp_file.  This reference is dropped when the channels
are unbridged, which can occur either explicitly on userspace calling
the PPPIOCUNBRIDGECHAN ioctl, or implicitly when either channel in the
bridge is unregistered.

In order to implement the channel bridge, struct channel is extended
with a new field, 'bridge', which points to the other struct channel
making up the bridge.

This pointer is RCU protected to avoid adding another lock to the data
path.

To guard against concurrent writes to the pointer, the existing struct
channel lock 'upl' coverage is extended rather than adding a new lock.

The 'upl' lock is used to protect the existing unit pointer.  Since the
bridge effectively replaces the unit (they're mutually exclusive for a
channel) it makes coding easier to use the same lock to cover them
both.

Signed-off-by: Tom Parkin 
Signed-off-by: David S. Miller

net: partially revert dynamic lockdep key changes

2020-05-04T19:05:56+00:00

This patch reverts the folowing commits:

commit 064ff66e2bef84f1153087612032b5b9eab005bd
"bonding: add missing netdev_update_lockdep_key()"

commit 53d374979ef147ab51f5d632dfe20b14aebeccd0
"net: avoid updating qdisc_xmit_lock_key in netdev_update_lockdep_key()"

commit 1f26c0d3d24125992ab0026b0dab16c08df947c7
"net: fix kernel-doc warning in "

commit ab92d68fc22f9afab480153bd82a20f6e2533769
"net: core: add generic lockdep keys"

but keeps the addr_list_lock_key because we still lock
addr_list_lock nestedly on stack devices, unlikely xmit_lock
this is safe because we don't take addr_list_lock on any fast
path.

Reported-and-tested-by: syzbot+aaa6fa4949cc5d9b7b25@syzkaller.appspotmail.com
Cc: Dmitry Vyukov 
Cc: Taehee Yoo 
Signed-off-by: Cong Wang 
Acked-by: Taehee Yoo 
Signed-off-by: David S. Miller