NULL Pointer Dereference Affecting kernel-default-base package, versions <5.14.21-150500.55.80.2.150500.6.35.6
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applicationsSnyk Learn
Learn about NULL Pointer Dereference vulnerabilities in an interactive lesson.
Start learning- Snyk IDSNYK-SLES155-KERNELDEFAULTBASE-8103596
- published28 Sept 2024
- disclosed27 Sept 2024
Introduced: 27 Sep 2024
CVE-2022-48865 (opens in a new tab)How to fix?
Upgrade SLES:15.5 kernel-default-base to version 5.14.21-150500.55.80.2.150500.6.35.6 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream kernel-default-base package and not the kernel-default-base package as distributed by SLES.
See How to fix? for SLES:15.5 relevant fixed versions and status.
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.
References
- https://www.suse.com/security/cve/CVE-2022-48865.html
- https://bugzilla.suse.com/1228065
- https://git.kernel.org/stable/c/2de76d37d4a6dca9b96ea51da24d4290e6cfa1a5
- https://git.kernel.org/stable/c/be4977b847f5d5cedb64d50eaaf2218c3a55a3a3
- https://git.kernel.org/stable/c/f4f59fdbc748805b08c13dae14c01f0518c77c94
- https://git.kernel.org/stable/c/f96dc3adb9a97b8f3dfdb88796483491a3006b71