In the Linux kernel, the following vulnerability has been resolved:
LoongArch: BPF: Don't override subprog's return value
The verifier test `calls: div by 0 in subprog` triggers a panic at the
ld.bu instruction. The ld.bu insn is trying to load byte from memory
address returned by the subprog. The subprog actually set the correct
address at the a5 register (dedicated register for BPF return values).
But at commit 73c359d1d356 ("LoongArch: BPF: Sign-extend return values")
we also sign extended a5 to the a0 register (return value in LoongArch).
For function call insn, we later propagate the a0 register back to a5
register. This is right for native calls but wrong for bpf2bpf calls
which expect zero-extended return value in a5 register. So only move a0
to a5 for native calls (i.e. non-BPF_PSEUDO_CALL).
LoongArch: BPF: Don't override subprog's return value
The verifier test `calls: div by 0 in subprog` triggers a panic at the
ld.bu instruction. The ld.bu insn is trying to load byte from memory
address returned by the subprog. The subprog actually set the correct
address at the a5 register (dedicated register for BPF return values).
But at commit 73c359d1d356 ("LoongArch: BPF: Sign-extend return values")
we also sign extended a5 to the a0 register (return value in LoongArch).
For function call insn, we later propagate the a0 register back to a5
register. This is right for native calls but wrong for bpf2bpf calls
which expect zero-extended return value in a5 register. So only move a0
to a5 for native calls (i.e. non-BPF_PSEUDO_CALL).
Metrics
Affected Vendors & Products
| Vendors | Products |
|---|---|
| Linux |
|
Configuration 1 [-]
|
No data.
No data.
Advisories
| Source | ID | Title |
|---|---|---|
 EUVD |
EUVD-2025-11259 | In the Linux kernel, the following vulnerability has been resolved: LoongArch: BPF: Don't override subprog's return value The verifier test `calls: div by 0 in subprog` triggers a panic at the ld.bu instruction. The ld.bu insn is trying to load byte from memory address returned by the subprog. The subprog actually set the correct address at the a5 register (dedicated register for BPF return values). But at commit 73c359d1d356 ("LoongArch: BPF: Sign-extend return values") we also sign extended a5 to the a0 register (return value in LoongArch). For function call insn, we later propagate the a0 register back to a5 register. This is right for native calls but wrong for bpf2bpf calls which expect zero-extended return value in a5 register. So only move a0 to a5 for native calls (i.e. non-BPF_PSEUDO_CALL). |
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Fri, 31 Oct 2025 20:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux
Linux linux Kernel |
|
| Weaknesses | NVD-CWE-noinfo | |
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
Fri, 18 Apr 2025 02:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
| |
| Metrics |
threat_severity
|
cvssV3_1
|
Wed, 16 Apr 2025 14:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: LoongArch: BPF: Don't override subprog's return value The verifier test `calls: div by 0 in subprog` triggers a panic at the ld.bu instruction. The ld.bu insn is trying to load byte from memory address returned by the subprog. The subprog actually set the correct address at the a5 register (dedicated register for BPF return values). But at commit 73c359d1d356 ("LoongArch: BPF: Sign-extend return values") we also sign extended a5 to the a0 register (return value in LoongArch). For function call insn, we later propagate the a0 register back to a5 register. This is right for native calls but wrong for bpf2bpf calls which expect zero-extended return value in a5 register. So only move a0 to a5 for native calls (i.e. non-BPF_PSEUDO_CALL). | |
| Title | LoongArch: BPF: Don't override subprog's return value | |
| References |
|
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2025-05-26T05:17:20.353Z
Reserved: 2024-12-29T08:45:45.810Z
Link: CVE-2025-22048
Vulnrichment
No data.
NVD
Status : Analyzed
Published: 2025-04-16T15:15:58.220
Modified: 2025-10-31T20:20:20.130
Link: CVE-2025-22048
Redhat
OpenCVE Enrichment
No data.