In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix potential UAF when reading bpf link info
In bpf_link_show_fdinfo and bpf_link_get_info_by_fd, link->prog is
accessed without holding any locks. If the prog is concurrently replaced
via bpf_link_update, the old prog can be freed, leading to a potential
UAF issue.
Fix this by accessing link->prog under RCU protection to safely fetch
the pointer and guarantee its lifetime while reading its fields.
Attack Parameters
Attack Vector
Local
Requires local access
Attack Complexity
Low
Easy to exploit
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v3.1
References 5
https://git.kernel.org/stable/c/79347e42cfbc9e78872922e8f08a70609c9af82f
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/85cf991c881e7198be32be05a9daa2625390c8b3
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/863f3ddd0b8ac65abfb50d3be0869268ac0e277b
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/a5c936ac904767fc1d943d40b0308bcb2ae2509b
416baaa9-dc9f-4396-8d5f-8c081fb06d67
https://git.kernel.org/stable/c/d7d7208e2603b45724b684f4df73904fb347741e
416baaa9-dc9f-4396-8d5f-8c081fb06d67