Attacker Value
Unknown
(0 users assessed)
Exploitability
Unknown
(0 users assessed)
User Interaction
None
Privileges Required
Low
Attack Vector
Local
0

CVE-2022-48848

Disclosure Date: July 16, 2024
Add MITRE ATT&CK tactics and techniques that apply to this CVE.

Description

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

tracing/osnoise: Do not unregister events twice

Nicolas reported that using:

# trace-cmd record -e all -M 10 -p osnoise —poll

Resulted in the following kernel warning:

——————[ cut here ]——————
WARNING: CPU: 0 PID: 1217 at kernel/tracepoint.c:404 tracepoint_probe_unregister+0x280/0x370
[…]
CPU: 0 PID: 1217 Comm: trace-cmd Not tainted 5.17.0-rc6-next-20220307-nico+ #19
RIP: 0010:tracepoint_probe_unregister+0x280/0x370
[…]
CR2: 00007ff919b29497 CR3: 0000000109da4005 CR4: 0000000000170ef0
Call Trace:
<TASK>
osnoise_workload_stop+0x36/0x90
tracing_set_tracer+0x108/0x260
tracing_set_trace_write+0x94/0xd0
? __check_object_size.part.0+0x10a/0x150
? selinux_file_permission+0x104/0x150
vfs_write+0xb5/0x290
ksys_write+0x5f/0xe0
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7ff919a18127
[…]
—–[ end trace 0000000000000000 ]—-

The warning complains about an attempt to unregister an
unregistered tracepoint.

This happens on trace-cmd because it first stops tracing, and
then switches the tracer to nop. Which is equivalent to:

# cd /sys/kernel/tracing/
# echo osnoise > current_tracer
# echo 0 > tracing_on
# echo nop > current_tracer

The osnoise tracer stops the workload when no trace instance
is actually collecting data. This can be caused both by
disabling tracing or disabling the tracer itself.

To avoid unregistering events twice, use the existing
trace_osnoise_callback_enabled variable to check if the events
(and the workload) are actually active before trying to
deactivate them.

Add Assessment

No one has assessed this topic. Be the first to add your voice to the community.

CVSS V3 Severity and Metrics
Base Score:
7.8 High
Impact Score:
5.9
Exploitability Score:
1.8
Vector:
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector (AV):
Local
Attack Complexity (AC):
Low
Privileges Required (PR):
Low
User Interaction (UI):
None
Scope (S):
Unchanged
Confidentiality (C):
High
Integrity (I):
High
Availability (A):
High

General Information

Vendors

  • linux

Products

  • linux kernel

Additional Info

Technical Analysis