Message ID | 20220221203539.310690-1-alvin@pqrs.dk (mailing list archive) |
---|---|
State | Accepted |
Commit | 342b6419193c6f697fd47d9c72fcff9cafc70687 |
Delegated to: | Netdev Maintainers |
Headers | show |
Series | [v2,net] net: dsa: fix panic when removing unoffloaded port from bridge | expand |
On Mon, Feb 21, 2022 at 09:35:38PM +0100, Alvin Šipraga wrote: > From: Alvin Šipraga <alsi@bang-olufsen.dk> > > If a bridged port is not offloaded to the hardware - either because the > underlying driver does not implement the port_bridge_{join,leave} ops, > or because the operation failed - then its dp->bridge pointer will be > NULL when dsa_port_bridge_leave() is called. Avoid dereferncing NULL. > > This fixes the following splat when removing a port from a bridge: > > Unable to handle kernel access to user memory outside uaccess routines at virtual address 0000000000000000 > Internal error: Oops: 96000004 [#1] PREEMPT_RT SMP > CPU: 3 PID: 1119 Comm: brctl Tainted: G O 5.17.0-rc4-rt4 #1 > Call trace: > dsa_port_bridge_leave+0x8c/0x1e4 > dsa_slave_changeupper+0x40/0x170 > dsa_slave_netdevice_event+0x494/0x4d4 > notifier_call_chain+0x80/0xe0 > raw_notifier_call_chain+0x1c/0x24 > call_netdevice_notifiers_info+0x5c/0xac > __netdev_upper_dev_unlink+0xa4/0x200 > netdev_upper_dev_unlink+0x38/0x60 > del_nbp+0x1b0/0x300 > br_del_if+0x38/0x114 > add_del_if+0x60/0xa0 > br_ioctl_stub+0x128/0x2dc > br_ioctl_call+0x68/0xb0 > dev_ifsioc+0x390/0x554 > dev_ioctl+0x128/0x400 > sock_do_ioctl+0xb4/0xf4 > sock_ioctl+0x12c/0x4e0 > __arm64_sys_ioctl+0xa8/0xf0 > invoke_syscall+0x4c/0x110 > el0_svc_common.constprop.0+0x48/0xf0 > do_el0_svc+0x28/0x84 > el0_svc+0x1c/0x50 > el0t_64_sync_handler+0xa8/0xb0 > el0t_64_sync+0x17c/0x180 > Code: f9402f00 f0002261 f9401302 913cc021 (a9401404) > ---[ end trace 0000000000000000 ]--- > > Fixes: d3eed0e57d5d ("net: dsa: keep the bridge_dev and bridge_num as part of the same structure") > Signed-off-by: Alvin Šipraga <alsi@bang-olufsen.dk> > --- Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
On 2/21/2022 12:35 PM, Alvin Šipraga wrote: > From: Alvin Šipraga <alsi@bang-olufsen.dk> > > If a bridged port is not offloaded to the hardware - either because the > underlying driver does not implement the port_bridge_{join,leave} ops, > or because the operation failed - then its dp->bridge pointer will be > NULL when dsa_port_bridge_leave() is called. Avoid dereferncing NULL. > > This fixes the following splat when removing a port from a bridge: > > Unable to handle kernel access to user memory outside uaccess routines at virtual address 0000000000000000 > Internal error: Oops: 96000004 [#1] PREEMPT_RT SMP > CPU: 3 PID: 1119 Comm: brctl Tainted: G O 5.17.0-rc4-rt4 #1 > Call trace: > dsa_port_bridge_leave+0x8c/0x1e4 > dsa_slave_changeupper+0x40/0x170 > dsa_slave_netdevice_event+0x494/0x4d4 > notifier_call_chain+0x80/0xe0 > raw_notifier_call_chain+0x1c/0x24 > call_netdevice_notifiers_info+0x5c/0xac > __netdev_upper_dev_unlink+0xa4/0x200 > netdev_upper_dev_unlink+0x38/0x60 > del_nbp+0x1b0/0x300 > br_del_if+0x38/0x114 > add_del_if+0x60/0xa0 > br_ioctl_stub+0x128/0x2dc > br_ioctl_call+0x68/0xb0 > dev_ifsioc+0x390/0x554 > dev_ioctl+0x128/0x400 > sock_do_ioctl+0xb4/0xf4 > sock_ioctl+0x12c/0x4e0 > __arm64_sys_ioctl+0xa8/0xf0 > invoke_syscall+0x4c/0x110 > el0_svc_common.constprop.0+0x48/0xf0 > do_el0_svc+0x28/0x84 > el0_svc+0x1c/0x50 > el0t_64_sync_handler+0xa8/0xb0 > el0t_64_sync+0x17c/0x180 > Code: f9402f00 f0002261 f9401302 913cc021 (a9401404) > ---[ end trace 0000000000000000 ]--- > > Fixes: d3eed0e57d5d ("net: dsa: keep the bridge_dev and bridge_num as part of the same structure") > Signed-off-by: Alvin Šipraga <alsi@bang-olufsen.dk> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Hello: This patch was applied to netdev/net.git (master) by Jakub Kicinski <kuba@kernel.org>: On Mon, 21 Feb 2022 21:35:38 +0100 you wrote: > From: Alvin Šipraga <alsi@bang-olufsen.dk> > > If a bridged port is not offloaded to the hardware - either because the > underlying driver does not implement the port_bridge_{join,leave} ops, > or because the operation failed - then its dp->bridge pointer will be > NULL when dsa_port_bridge_leave() is called. Avoid dereferncing NULL. > > [...] Here is the summary with links: - [v2,net] net: dsa: fix panic when removing unoffloaded port from bridge https://git.kernel.org/netdev/net/c/342b6419193c You are awesome, thank you!
diff --git a/net/dsa/port.c b/net/dsa/port.c index eef4a98f2628..1a40c52f5a42 100644 --- a/net/dsa/port.c +++ b/net/dsa/port.c @@ -395,10 +395,17 @@ void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br) .tree_index = dp->ds->dst->index, .sw_index = dp->ds->index, .port = dp->index, - .bridge = *dp->bridge, }; int err; + /* If the port could not be offloaded to begin with, then + * there is nothing to do. + */ + if (!dp->bridge) + return; + + info.bridge = *dp->bridge; + /* Here the port is already unbridged. Reflect the current configuration * so that drivers can program their chips accordingly. */