RDMA/siw: Fix a use after free in siw_alloc_mr
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 3 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.
Summary
In the Linux kernel, the following vulnerability has been resolved: RDMA/siw: Fix a use after free in siw_alloc_mr Our code analyzer reported a UAF. In siw_alloc_mr(), it calls siw_mr_add_mem(mr,..). In the implementation of siw_mr_add_mem(), mem is assigned to mr->mem and then mem is freed via kfree(mem) if xa_alloc_cyclic() failed. Here, mr->mem still point to a freed object. After, the execution continue up to the err_out branch of siw_alloc_mr, and the freed mr->mem is used in siw_mr_drop_mem(mr). My patch moves "mr->mem = mem" behind the if (xa_alloc_cyclic(..)<0) {} section, to avoid the uaf.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 5.3 and later | 5.4.119, 5.10.37, 5.11.21, 5.12.4, 5.13 | Patch available | CNA |
- Linux VendorLinux Affected 5.3 and later Fixed in 5.4.119, 5.10.37, 5.11.21, 5.12.4, 5.13 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 5.3 to before 5.4.119; 5.5 to before 5.10.37; 5.11 to before 5.11.21; 5.12 to before 5.12.4 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.3 to before 5.4.119; 5.5 to before 5.10.37; 5.11 to before 5.11.21; 5.12 to before 5.12.4 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.4.119, 5.10.37, 5.11.21, 5.12.4, 5.13
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 8 | Affected | No fix yet |
Not affected: 1 product
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2021-47012
- 2026-10-03 Alias added: GHSA-65x6-qq63-m88g
References
Patch 5
- https://git.kernel.org/stable/c/30b9e92d0b5e5d5dc1101ab856c17009537cbca4
- https://git.kernel.org/stable/c/608a4b90ece039940e9425ee2b39c8beff27e00c
- https://git.kernel.org/stable/c/3e22b88e02c194f6c80867abfef5cc09383461f4
- https://git.kernel.org/stable/c/ad9ce7188432650469a6c7625bf479f5ed0b6155
- https://git.kernel.org/stable/c/3093ee182f01689b89e9f8797b321603e5de4f63
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Sources
- CVE-2021-47012 · CVE Program
- CVE-2021-47012 · NVD
- FIRST EPSS
- GHSA-65x6-qq63-m88g · GitHub Advisory Database · CC BY 4.0
- CVE-2021-47012 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences