mirror of
https://github.com/torvalds/linux.git
synced 2026-07-28 18:21:24 +02:00
In the HSR (High-availability Seamless Redundancy) protocol, node
information is maintained in the node_db. When a supervision frame is
received, node->addr_B_port is updated to track the receiving port type
(e.g., HSR_PT_SLAVE_B).
If the underlying physical interface associated with this slave port is
removed (e.g., via `ip link del`), hsr_del_port() frees the hsr_port
object. However, the stale node->addr_B_port reference is kept in the
node_db until the node ages out.
Subsequently, if userspace queries the node status via the Netlink
command HSR_C_GET_NODE_STATUS, the kernel calls hsr_get_node_data().
This function unconditionally dereferences the pointer returned by
hsr_port_get_hsr():
if (node->addr_B_port != HSR_PT_NONE) {
port = hsr_port_get_hsr(hsr, node->addr_B_port);
*addr_b_ifindex = port->dev->ifindex; // <-- NULL deref
}
If the slave port has been deleted, hsr_port_get_hsr() returns NULL,
resulting in a kernel panic.
Oops: general protection fault, probably for non-canonical address
KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017]
RIP: 0010:hsr_get_node_data+0x7b6/0x9e0
Call Trace:
<TASK>
hsr_get_node_status+0x445/0xa40
Fix this by adding a proper NULL pointer check. If the port lookup fails
due to a stale port type, gracefully treat it as if no valid port exists
and assign -1 to the interface index.
Steps to reproduce:
1. Create an HSR interface with two slave devices.
2. Receive a supervision frame to populate node_db with
addr_B_port assigned to SLAVE_B.
3. Delete the underlying slave device B.
4. Send an HSR_C_GET_NODE_STATUS Netlink message.
Fixes:
|
||
|---|---|---|
| .. | ||
| hsr_debugfs.c | ||
| hsr_device.c | ||
| hsr_device.h | ||
| hsr_forward.c | ||
| hsr_forward.h | ||
| hsr_framereg.c | ||
| hsr_framereg.h | ||
| hsr_main.c | ||
| hsr_main.h | ||
| hsr_netlink.c | ||
| hsr_netlink.h | ||
| hsr_slave.c | ||
| hsr_slave.h | ||
| Kconfig | ||
| Makefile | ||
| prp_dup_discard_test.c | ||