The bridge-stp usermode helper is currently restricted to the initial
network namespace, preventing userspace STP daemons (e.g. mstpd) from
operating on bridges in other network namespaces. Since commit
ff62198553 ("bridge: Only call /sbin/bridge-stp for the initial
network namespace"), bridges in non-init namespaces silently fall
back to kernel STP with no way to use userspace STP.
Add a new bridge attribute IFLA_BR_STP_MODE that allows explicit
per-bridge control over STP mode selection:
BR_STP_MODE_AUTO (default) - Existing behavior: invoke the
/sbin/bridge-stp helper in init_net only; fall back to kernel STP
if it fails or in non-init namespaces.
BR_STP_MODE_USER - Directly enable userspace STP (BR_USER_STP)
without invoking the helper. Works in any network namespace.
Userspace is responsible for ensuring an STP daemon manages the
bridge.
BR_STP_MODE_KERNEL - Directly enable kernel STP (BR_KERNEL_STP)
without invoking the helper.
The mode can only be changed while STP is disabled, or set to the
same value (-EBUSY otherwise). IFLA_BR_STP_MODE is processed before
IFLA_BR_STP_STATE in br_changelink(), so both can be set atomically
in a single netlink message. The mode can also be changed in the
same message that disables STP.
The stp_mode struct field is u8 since all possible values fit, while
NLA_U32 is used for the netlink attribute since it occupies the same
space in the netlink message as NLA_U8.
A new stp_helper_active boolean tracks whether the /sbin/bridge-stp
helper was invoked during br_stp_start(), so that br_stp_stop() only
calls the helper for stop when it was called for start. This avoids
calling the helper asymmetrically when stp_mode changes between
start and stop.
Suggested-by: Ido Schimmel <idosch@nvidia.com>
Assisted-by: Claude:claude-opus-4-6
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: Andy Roulin <aroulin@nvidia.com>
Link: https://patch.msgid.link/20260405205224.3163000-2-aroulin@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When booting with the 'ipv6.disable=1' parameter, the nd_tbl is never
initialized because inet6_init() exits before ndisc_init() is called
which initializes it. Then, if neigh_suppress is enabled and an ICMPv6
Neighbor Discovery packet reaches the bridge, br_do_suppress_nd() will
dereference ipv6_stub->nd_tbl which is NULL, passing it to
neigh_lookup(). This causes a kernel NULL pointer dereference.
BUG: kernel NULL pointer dereference, address: 0000000000000268
Oops: 0000 [#1] PREEMPT SMP NOPTI
[...]
RIP: 0010:neigh_lookup+0x16/0xe0
[...]
Call Trace:
<IRQ>
? neigh_lookup+0x16/0xe0
br_do_suppress_nd+0x160/0x290 [bridge]
br_handle_frame_finish+0x500/0x620 [bridge]
br_handle_frame+0x353/0x440 [bridge]
__netif_receive_skb_core.constprop.0+0x298/0x1110
__netif_receive_skb_one_core+0x3d/0xa0
process_backlog+0xa0/0x140
__napi_poll+0x2c/0x170
net_rx_action+0x2c4/0x3a0
handle_softirqs+0xd0/0x270
do_softirq+0x3f/0x60
Fix this by replacing IS_ENABLED(IPV6) call with ipv6_mod_enabled() in
the callers. This is in essence disabling NS/NA suppression when IPv6 is
disabled.
Fixes: ed842faeb2 ("bridge: suppress nd pkts on BR_NEIGH_SUPPRESS ports")
Reported-by: Guruprasad C P <gurucp2005@gmail.com>
Closes: https://lore.kernel.org/netdev/CAHXs0ORzd62QOG-Fttqa2Cx_A_VFp=utE2H2VTX5nqfgs7LDxQ@mail.gmail.com/
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260304120357.9778-1-fmancera@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
Move the more esoteric helpers for netdev instance lock to
a dedicated header. This avoids growing netdevice.h to infinity
and makes rebuilding the kernel much faster (after touching
the header with the helpers).
The main netdev_lock() / netdev_unlock() functions are used
in static inlines in netdevice.h and will probably be used
most commonly, so keep them in netdevice.h.
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250307183006.2312761-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
"Interface can't change network namespaces" is rather an attribute,
not a feature, and it can't be changed via Ethtool.
Make it a "cold" private flag instead of a netdev_feature and free
one more bit.
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
NETIF_F_LLTX can't be changed via Ethtool and is not a feature,
rather an attribute, very similar to IFF_NO_QUEUE (and hot).
Free one netdev_features_t bit and make it a "hot" private flag.
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
In br_fill_forward_path(), f->dst is checked not to be NULL, then
immediately read using READ_ONCE and checked again. The first check is
useless, so this patch aims to remove the redundant check of f->dst.
Signed-off-by: linke li <lilinke99@qq.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
With commit 34d21de99c ("net: Move {l,t,d}stats allocation to core and
convert veth & vrf"), stats allocation could be done on net core
instead of this driver.
With this new approach, the driver doesn't have to bother with error
handling (allocation failure checking, making sure free happens in the
right spot, etc). This is core responsibility now.
Remove the allocation in the bridge driver and leverage the network
core allocation.
Signed-off-by: Breno Leitao <leitao@debian.org>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20240227182338.2739884-1-leitao@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Since commit aed65af1cc ("drivers: make device_type const"), the driver
core can properly handle constant struct device_type. Move the br_type
variable to be a constant structure as well, placing it into read-only
memory which can not be modified at runtime.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement MDB bulk deletion support in the bridge driver, allowing MDB
entries to be deleted in bulk according to provided parameters.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement support for MDB get operation by looking up a matching MDB
entry, allocating the skb according to the entry's size and then filling
in the response. The operation is performed under the bridge multicast
lock to ensure that the entry does not change between the time the reply
size is determined and when the reply is filled in.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current name is going to conflict with the upcoming net device
operation for the MDB get operation.
Rename the function to br_mdb_entry_skb_get(). No functional changes
intended.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
For EVPN non-DF (Designated Forwarder) filtering we need to be able to
prevent decapsulated traffic from being flooded to a multi-homed host.
Filtering of multicast and broadcast traffic can be achieved using the
following flower filter:
# tc filter add dev bond0 egress pref 1 proto all flower indev vxlan0 dst_mac 01:00:00:00:00:00/01:00:00:00:00:00 action drop
Unlike broadcast and multicast traffic, it is not currently possible to
filter unknown unicast traffic. The classification into unknown unicast
is performed by the bridge driver, but is not visible to other layers
such as tc.
Solve this by adding a new 'l2_miss' bit to the tc skb extension. Clear
the bit whenever a packet enters the bridge (received from a bridge port
or transmitted via the bridge) and set it if the packet did not match an
FDB or MDB entry. If there is no skb extension and the bit needs to be
cleared, then do not allocate one as no extension is equivalent to the
bit being cleared. The bit is not set for broadcast packets as they
never perform a lookup and therefore never incur a miss.
A bit that is set for every flooded packet would also work for the
current use case, but it does not allow us to differentiate between
registered and unregistered multicast traffic, which might be useful in
the future.
To keep the performance impact to a minimum, the marking of packets is
guarded by the 'tc_skb_ext_tc' static key. When 'false', the skb is not
touched and an skb extension is not allocated. Instead, only a
5 bytes nop is executed, as demonstrated below for the call site in
br_handle_frame().
Before the patch:
```
memset(skb->cb, 0, sizeof(struct br_input_skb_cb));
c37b09: 49 c7 44 24 28 00 00 movq $0x0,0x28(%r12)
c37b10: 00 00
p = br_port_get_rcu(skb->dev);
c37b12: 49 8b 44 24 10 mov 0x10(%r12),%rax
memset(skb->cb, 0, sizeof(struct br_input_skb_cb));
c37b17: 49 c7 44 24 30 00 00 movq $0x0,0x30(%r12)
c37b1e: 00 00
c37b20: 49 c7 44 24 38 00 00 movq $0x0,0x38(%r12)
c37b27: 00 00
```
After the patch (when static key is disabled):
```
memset(skb->cb, 0, sizeof(struct br_input_skb_cb));
c37c29: 49 c7 44 24 28 00 00 movq $0x0,0x28(%r12)
c37c30: 00 00
c37c32: 49 8d 44 24 28 lea 0x28(%r12),%rax
c37c37: 48 c7 40 08 00 00 00 movq $0x0,0x8(%rax)
c37c3e: 00
c37c3f: 48 c7 40 10 00 00 00 movq $0x0,0x10(%rax)
c37c46: 00
#ifdef CONFIG_HAVE_JUMP_LABEL_HACK
static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
{
asm_volatile_goto("1:"
c37c47: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1)
br_tc_skb_miss_set(skb, false);
p = br_port_get_rcu(skb->dev);
c37c4c: 49 8b 44 24 10 mov 0x10(%r12),%rax
```
Subsequent patches will extend the flower classifier to be able to match
on the new 'l2_miss' bit and enable / disable the static key when
filters that match on it are added / deleted.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Subsequent patches are going to add per-{Port, VLAN} neighbor
suppression, which will require br_flood() to potentially suppress ARP /
NS packets on a per-{Port, VLAN} basis.
As a preparation, pass the VLAN ID of the packet as another argument to
br_flood().
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, the bridge driver registers handlers for MDB netlink
messages, making it impossible for other drivers to implement MDB
support.
As a preparation for VXLAN MDB support, move the MDB handlers out of the
bridge driver to the core rtnetlink code. The rtnetlink code will call
into individual drivers by invoking their previously added MDB net
device operations.
Note that while the diffstat is large, the change is mechanical. It
moves code out of the bridge driver to rtnetlink code. Also note that a
similar change was made in 2012 with commit 77162022ab ("net: add
generic PF_BRIDGE:RTM_ FDB hooks") that moved FDB handlers out of the
bridge driver to the core rtnetlink code.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement the previously added MDB net device operations in the bridge
driver so that they could be invoked by core rtnetlink code in the next
patch.
The operations are identical to the existing br_mdb_{dump,add,del}
functions. The '_new' suffix will be removed in the next patch. The
functions are re-implemented in this patch to make the conversion in the
next patch easier to review.
Add dummy implementations when 'CONFIG_BRIDGE_IGMP_SNOOPING' is
disabled, so that an error will be returned to user space when it is
trying to add or delete an MDB entry. This is consistent with existing
behavior where the bridge driver does not even register rtnetlink
handlers for RTM_{NEW,DEL,GET}MDB messages when this Kconfig option is
disabled.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
