kernel/linux.git/drivers/net/team, branch v7.1-rc6

net: team: fix NULL pointer dereference in team_xmit during mode change

2026-05-26T08:49:16+00:00

__team_change_mode() clears team->ops with memset() before restoring safe dummy handlers via team_adjust_ops(). A concurrent team_xmit() running under RCU on another CPU can read team->ops.transmit during this window and call a NULL function pointer, crashing the kernel. The race requires a mode change (CAP_NET_ADMIN) concurrent with transmit on the team device. BUG: kernel NULL pointer dereference, address: 0000000000000000 Oops: 0010 [#1] SMP KASAN NOPTI RIP: 0010:0x0 Call Trace: team_xmit (drivers/net/team/team_core.c:1853) dev_hard_start_xmit (net/core/dev.c:3904) __dev_queue_xmit (net/core/dev.c:4871) packet_sendmsg (net/packet/af_packet.c:3109) __sys_sendto (net/socket.c:2265) The original code assumed that no ports means no traffic, so mode changes could freely memset()/memcpy() the ops. AF_PACKET with forced carrier breaks that assumption. Prevent the race instead of making it safe: replace memset()/memcpy() with per-field updates that never touch transmit or receive. Those two handlers are managed solely by team_adjust_ops(), which already installs dummies when tx_en_port_count == 0 (always true during mode change since no ports are present). WRITE_ONCE/READ_ONCE prevent store/load tearing on the handler pointers. synchronize_net() before exit_op() drains in-flight readers that may still reference old mode state from before port removal switched the handlers to dummies. Fixes: 3d249d4ca7d0 ("net: introduce ethernet teaming device") Reported-by: Xiang Mei Signed-off-by: Weiming Shi Reviewed-by: Jiayuan Chen Link: https://patch.msgid.link/20260521081159.1491563-3-bestswngs@gmail.com Signed-off-by: Paolo Abeni

net: team: Add new tx_enabled team port option

2026-04-13T13:09:49+00:00

This option allows independent control over tx enablement without affecting rx enablement. Like the rx_enabled option, this also implicitly affects the enabled option. If this option is not used, then the enabled option will continue to behave as it did before. Tested in a follow-up patch with a new selftest. Reviewed-by: Jiri Pirko Signed-off-by: Marc Harvey Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260409-teaming-driver-internal-v7-9-f47e7589685d@google.com Signed-off-by: Paolo Abeni

net: team: Add new rx_enabled team port option

2026-04-13T13:09:49+00:00

Allow independent control over rx enablement via the rx_enabled option without affecting tx enablement. This affects the normal enabled option since a port is only considered enabled if both tx and rx are enabled. If this option is not used, then the enabled option will continue to behave exactly as it did before. Tested in a follow-up patch with a new selftest. Reviewed-by: Jiri Pirko Signed-off-by: Marc Harvey Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260409-teaming-driver-internal-v7-8-f47e7589685d@google.com Signed-off-by: Paolo Abeni

net: team: Track rx enablement separately from tx enablement

2026-04-13T13:09:49+00:00

Separate the rx and tx enablement/disablement into different functions so that it is easier to interact with them independently later. Although this patch changes receive and transmit paths, the actual behavior of the teaming driver should remain unchanged, since there is no option introduced yet to change rx or tx enablement independently. Those options will be added in follow-up patches. Reviewed-by: Jiri Pirko Signed-off-by: Marc Harvey Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260409-teaming-driver-internal-v7-7-f47e7589685d@google.com Signed-off-by: Paolo Abeni

net: team: Rename enablement functions and struct members to tx

2026-04-13T13:09:49+00:00

Add no functional changes, but rename enablement functions, variables etc. that are used in teaming driver transmit decisions. Since rx and tx enablement are still coupled, some of the variables renamed in this patch are still used for the rx path, but that will change in a follow-up patch. Reviewed-by: Jiri Pirko Signed-off-by: Marc Harvey Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260409-teaming-driver-internal-v7-6-f47e7589685d@google.com Signed-off-by: Paolo Abeni

net: team: Rename port_disabled team mode op to port_tx_disabled

2026-04-13T13:09:48+00:00

This team mode op is only used by the load balance mode, and it only uses it in the tx path. Reviewed-by: Jiri Pirko Signed-off-by: Marc Harvey Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260409-teaming-driver-internal-v7-3-f47e7589685d@google.com Signed-off-by: Paolo Abeni

net: team: Remove unused team_mode_op, port_enabled

2026-04-13T13:09:48+00:00

This team_mode_op wasn't used by any of the team modes, so remove it. Reviewed-by: Jiri Pirko Signed-off-by: Marc Harvey Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260409-teaming-driver-internal-v7-2-f47e7589685d@google.com Signed-off-by: Paolo Abeni

net: team: Annotate reads and writes for mixed lock accessed values

2026-04-13T13:09:48+00:00

The team_port's "index" and the team's "en_port_count" are read in the hot transmit path, but are only written to when holding the rtnl lock. Use READ_ONCE() for all lockless reads of these values, and use WRITE_ONCE() for all writes. Reviewed-by: Jiri Pirko Signed-off-by: Marc Harvey Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260409-teaming-driver-internal-v7-1-f47e7589685d@google.com Signed-off-by: Paolo Abeni

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

2026-03-26T19:09:57+00:00

Cross-merge networking fixes after downstream PR (net-7.0-rc6). No conflicts, or adjacent changes. Signed-off-by: Jakub Kicinski

team: fix header_ops type confusion with non-Ethernet ports

2026-03-24T10:26:32+00:00

Similar to commit 950803f72547 ("bonding: fix type confusion in bond_setup_by_slave()") team has the same class of header_ops type confusion. For non-Ethernet ports, team_setup_by_port() copies port_dev->header_ops directly. When the team device later calls dev_hard_header() or dev_parse_header(), these callbacks can run with the team net_device instead of the real lower device, so netdev_priv(dev) is interpreted as the wrong private type and can crash. The syzbot report shows a crash in bond_header_create(), but the root cause is in team: the topology is gre -> bond -> team, and team calls the inherited header_ops with its own net_device instead of the lower device, so bond_header_create() receives a team device and interprets netdev_priv() as bonding private data, causing a type confusion crash. Fix this by introducing team header_ops wrappers for create/parse, selecting a team port under RCU, and calling the lower device callbacks with port->dev, so each callback always sees the correct net_device context. Also pass the selected lower device to the lower parse callback, so recursion is bounded in stacked non-Ethernet topologies and parse callbacks always run with the correct device context. Fixes: 1d76efe1577b ("team: add support for non-ethernet devices") Reported-by: syzbot+3d8bc31c45e11450f24c@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/69b46af7.050a0220.36eb34.000e.GAE@google.com/T/ Cc: Jiayuan Chen Signed-off-by: Jiayuan Chen Link: https://patch.msgid.link/20260320072139.134249-2-jiayuan.chen@linux.dev Signed-off-by: Paolo Abeni