Description

In the Linux kernel, the following vulnerability has been resolved: tipc: fix kernel panic when enabling bearer When enabling a bearer on a node, a kernel panic is observed: [ 4.498085] RIP: 0010:tipc_mon_prep+0x4e/0x130 [tipc] ... [ 4.520030] Call Trace: [ 4.520689] <IRQ> [ 4.521236] tipc_link_build_proto_msg+0x375/0x750 [tipc] [ 4.522654] tipc_link_build_state_msg+0x48/0xc0 [tipc] [ 4.524034] __tipc_node_link_up+0xd7/0x290 [tipc] [ 4.525292] tipc_rcv+0x5da/0x730 [tipc] [ 4.526346] ? __netif_receive_skb_core+0xb7/0xfc0 [ 4.527601] tipc_l2_rcv_msg+0x5e/0x90 [tipc] [ 4.528737] __netif_receive_skb_list_core+0x20b/0x260 [ 4.530068] netif_receive_skb_list_internal+0x1bf/0x2e0 [ 4.531450] ? dev_gro_receive+0x4c2/0x680 [ 4.532512] napi_complete_done+0x6f/0x180 [ 4.533570] virtnet_poll+0x29c/0x42e [virtio_net] ... The node in question is receiving activate messages in another thread after changing bearer status to allow message sending/ receiving in current thread: thread 1 | thread 2 -------- | -------- | tipc_enable_bearer() | test_and_set_bit_lock() | tipc_bearer_xmit_skb() | | tipc_l2_rcv_msg() | tipc_rcv() | __tipc_node_link_up() | tipc_link_build_state_msg() | tipc_link_build_proto_msg() | tipc_mon_prep() | { | ... | // null-pointer dereference | u16 gen = mon->dom_gen; | ... | } // Not being executed yet | tipc_mon_create() | { | ... | // allocate | mon = kzalloc(); | ... | } | Monitoring pointer in thread 2 is dereferenced before monitoring data is allocated in thread 1. This causes kernel panic. This commit fixes it by allocating the monitoring data before enabling the bearer to receive messages.

Metrics

 

CVSS Version 4.0 CVSS Version 3.x CVSS Version 2.0

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.

CVSS 4.0 Severity and Vector Strings:

NIST: NVD

N/A

NVD assessment not yet provided.

CVSS 3.x Severity and Vector Strings:

NIST: NVD

Base Score:  N/A

NVD assessment not yet provided.

CVSS 2.0 Severity and Vector Strings:

NIST: NVD

Base Score: N/A

NVD assessment not yet provided.

In the Linux kernel, the following vulnerability has been resolved:

tipc: fix kernel panic when enabling bearer

When enabling a bearer on a node, a kernel panic is observed:

[    4.498085] RIP: 0010:tipc_mon_prep+0x4e/0x130 [tipc]
...
[    4.520030] Call Trace:
[    4.520689]  <IRQ>
[    4.521236]  tipc_link_build_proto_msg+0x375/0x750 [tipc]
[    4.522654]  tipc_link_build_state_msg+0x48/0xc0 [tipc]
[    4.524034]  __tipc_node_link_up+0xd7/0x290 [tipc]
[    4.525292]  tipc_rcv+0x5da/0x730 [t

kernel.org https://git.kernel.org/stable/c/2de76d37d4a6dca9b96ea51da24d4290e6cfa1a5 [No types assigned]

kernel.org https://git.kernel.org/stable/c/be4977b847f5d5cedb64d50eaaf2218c3a55a3a3 [No types assigned]

kernel.org https://git.kernel.org/stable/c/f4f59fdbc748805b08c13dae14c01f0518c77c94 [No types assigned]

kernel.org https://git.kernel.org/stable/c/f96dc3adb9a97b8f3dfdb88796483491a3006b71 [No types assigned]