similar to: [Bridge] [PATCH] (4/4) bridge forwarding table RCU

A malicious actor behind one bridge port may spam the kernel with packets with a random source MAC address, each of which will create an FDB entry, each of which is a dynamic allocation in the kernel. There are roughly 2^48 different MAC addresses, further limited by the rhashtable they are stored in to 2^31. Each entry is of the type struct net_bridge_fdb_entry, which is currently 128 bytes big.

The following 3 locks would race against each other, causing the deadlock situation in the Syzbot bug report: - j1939_socks_lock - active_session_list_lock - sk_session_queue_lock A reasonable fix is to change j1939_socks_lock to an rwlock, since in the rare situations where a write lock is required for the linked list that j1939_socks_lock is protecting, the code does not attempt to acquire any

On 15/05/2023 11:50, Johannes Nixdorf wrote: > A malicious actor behind one bridge port may spam the kernel with packets > with a random source MAC address, each of which will create an FDB entry, > each of which is a dynamic allocation in the kernel. > > There are roughly 2^48 different MAC addresses, further limited by the > rhashtable they are stored in to 2^31. Each entry is

On Tue, Jun 20, 2023 at 09:55:31AM +0300, Nikolay Aleksandrov wrote: > On 6/19/23 10:14, Johannes Nixdorf wrote: > > +/* Set a FDB flag that implies the entry was not learned, and account > > + * for changes in the learned status. > > + */ > > +static void __fdb_set_flag_not_learned(struct net_bridge *br, > > + struct net_bridge_fdb_entry *fdb, > >

On 20/06/2023 16:35, Johannes Nixdorf wrote: > On Tue, Jun 20, 2023 at 09:55:31AM +0300, Nikolay Aleksandrov wrote: >> On 6/19/23 10:14, Johannes Nixdorf wrote: >>> +/* Set a FDB flag that implies the entry was not learned, and account >>> + * for changes in the learned status. >>> + */ >>> +static void __fdb_set_flag_not_learned(struct net_bridge *br,

A malicious actor behind one bridge port may spam the kernel with packets with a random source MAC address, each of which will create an FDB entry, each of which is a dynamic allocation in the kernel. There are roughly 2^48 different MAC addresses, further limited by the rhashtable they are stored in to 2^31. Each entry is of the type struct net_bridge_fdb_entry, which is currently 128 bytes big.

Replace the existing mac hash in the bridge code with the nice inline jenkins hash. This should provide better distribution across hash buckets and compiles to code that is similar in complexity. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> diff -Nru a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c --- a/net/bridge/br_fdb.c 2005-03-10 15:05:11 -08:00 +++ b/net/bridge/br_fdb.c

Hello, I just made some change of the bridge source which under kernel 2.4.20 ,to make it work automatically without any ioctl commands such as brctl .In this module I do ,it has only one br named BRIDGE which auto constructed in the module initiation ,and defined as a global variable "brg".And I add one eth card(eth0) to the br as a port .The main program is just below this page. But

This patch fixes the following compile error with CONFIG_BRIDGE=y and CONFIG_ATM_LANE=m: <-- snip --> ... LD .tmp_vmlinux1 net/built-in.o(.init.text+0x3ad1): In function `br_init': : undefined reference to `br_fdb_get_hook' net/built-in.o(.init.text+0x3adb): In function `br_init': : undefined reference to `br_fdb_put_hook' net/built-in.o(.exit.text+0xa2): In

Hi, The attached patches enables the bridge to filter and forward packets according to their IEEE 802.1q headers. The goals behind this change include : - Enable running STP on 802.1q tagged networks. STP packets must be untagged. It isn't obvious how else to enable STP with the current bridge and vlan code. - Add native support for an untagged vlan. Currently an untagged vlan can

Changes since v9: * series re-ordering so make functionality more distinct. Basic vlan filtering is patches 1-4. Support for PVID/untagged vlans is patches 5 and 6. VLAN support for FDB/MDB is patches 7-11. Patch 12 is still additional egress policy. * Slight simplification to code that extracts the VID from skb. Since we now depend on the vlan module, at the time of input skb_tci is

This series of patches provides an ability to add VLANs to the bridge ports. This is similar to what can be found in most switches. The bridge port may have any number of VLANs added to it including vlan 0 priority tagged traffic. When vlans are added to the port, only traffic tagged with particular vlan will forwarded over this port. Additionally, vlan ids are added to FDB entries and become

Introduce a limit on the amount of learned FDB entries on a bridge, configured by netlink with a build time default on bridge creation in the kernel config. For backwards compatibility the kernel config default is disabling the limit (0). Without any limit a malicious actor may OOM a kernel by spamming packets with changing MAC addresses on their bridge port, so allow the bridge creator to limit

This patch adds basic Virtual Ethernet Port Aggregator (VEPA) capabilities to the Linux kernel Ethernet bridging code. A Virtual Ethernet Port Aggregator (VEPA) is a capability within a physical end station that collaborates with an adjacent, external bridge to provide distributed bridging support between multiple virtual end stations and external networks. The VEPA collaborates by forwarding all

This patch adds basic Virtual Ethernet Port Aggregator (VEPA) capabilities to the Linux kernel Ethernet bridging code. A Virtual Ethernet Port Aggregator (VEPA) is a capability within a physical end station that collaborates with an adjacent, external bridge to provide distributed bridging support between multiple virtual end stations and external networks. The VEPA collaborates by forwarding all

This patch adds basic Virtual Ethernet Port Aggregator (VEPA) capabilities to the Linux kernel Ethernet bridging code. A Virtual Ethernet Port Aggregator (VEPA) is a capability within a physical end station that collaborates with an adjacent, external bridge to provide distributed bridging support between multiple virtual end stations and external networks. The VEPA collaborates by forwarding all

OK please try the following patch [PATCH] neighbour: fix a race in neigh_destroy() There is a race in neighbour code, because neigh_destroy() uses skb_queue_purge(&neigh->arp_queue) without holding neighbour lock, while other parts of the code assume neighbour rwlock is what protects arp_queue Convert all skb_queue_purge() calls to the __skb_queue_purge() variant Use

Hi, My current code is tripping the following assertion: lib/libzpool/build-kernel/arc.c:736: arc_change_state: Assertion `new_state->size + to_delta >= new_state->lsize (0x2a60000 >= 0x2a64000)` failed. gdb info: Program terminated with signal 6, Aborted. #0 0x00002afcd767847b in raise () from /lib/libc.so.6 (gdb) bt #0 0x00002afcd767847b in raise () from /lib/libc.so.6 #1

There is a structural problem in switchdev, where the flag bits in struct switchdev_notifier_fdb_info (added_by_user, is_local etc) only represent a simplified / denatured view of what's in struct net_bridge_fdb_entry :: flags (BR_FDB_ADDED_BY_USER, BR_FDB_LOCAL etc). Each time we want to pass more information about struct net_bridge_fdb_entry :: flags to struct switchdev_notifier_fdb_info

Hi Si-Wei, Thank you for the patch! Yet something to improve: [auto build test ERROR on net/master] url: https://github.com/0day-ci/linux/commits/Si-Wei-Liu/failover-allow-name-change-on-IFF_UP-slave-interfaces/20190329-195445 config: x86_64-lkp (attached as .config) compiler: gcc-7 (Debian 7.3.0-1) 7.3.0 reproduce: # save the attached .config to linux build tree make