In the Linux kernel, the following vulnerability has been resolved:
bpf, sockmap: Prevent lock inversion deadlock in map delete elem
syzkaller started using corpuses where a BPF tracing program deletes
elements from a sockmap/sockhash map. Because BPF tracing programs can be
invoked from any interrupt context, locks taken during a map_delete_elem
operation must be hardirq-safe. Otherwise a deadlock due to lock inversion
is possible, as reported by lockdep:
CPU0 CPU1
---- ----
lock(&htab->buckets[i].lock);
local_irq_disable();
lock(&host->lock);
lock(&htab->buckets[i].lock);
CVE Status: Analyzed
Attribute | Value |
---|---|
Attack Complexity | LOW |
Attack Vector | LOCAL |
Availability Impact | HIGH |
Base Score | 5.5 |
Base Severity | MEDIUM |
Confidentiality Impact | NONE |
Integrity Impact | NONE |
Privileges Required | LOW |
Scope | UNCHANGED |
User Interaction | NONE |
Vector String | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Exploitability Score | 1.8 |
Impact Score | 3.6 |
Source | [email protected] |
Type | Primary |