bpf: Fix request_sock leak in sk lookup helpers
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
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| Linux | Linux | unaffected |
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| Linux | Linux | affected |
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Configuration 1 [-]
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| Package | CPE | Advisory | Released Date |
|---|---|---|---|
| Red Hat Enterprise Linux 8 | |||
| kernel-0:4.18.0-425.3.1.el8 | cpe:/o:redhat:enterprise_linux:8 | RHSA-2022:7683 | 2022-11-08T00:00:00Z |
| Red Hat Enterprise Linux 9 | |||
| kernel-0:5.14.0-162.6.1.el9_1 | cpe:/a:redhat:enterprise_linux:9 | RHSA-2022:8267 | 2022-11-15T00:00:00Z |
| kernel-0:5.14.0-162.6.1.el9_1 | cpe:/o:redhat:enterprise_linux:9 | RHSA-2022:8267 | 2022-11-15T00:00:00Z |
No data available yet.
| Source | ID | Title |
|---|---|---|
EUVD |
EUVD-2022-54538 | In the Linux kernel, the following vulnerability has been resolved: bpf: Fix request_sock leak in sk lookup helpers A customer reported a request_socket leak in a Calico cloud environment. We found that a BPF program was doing a socket lookup with takes a refcnt on the socket and that it was finding the request_socket but returning the parent LISTEN socket via sk_to_full_sk() without decrementing the child request socket 1st, resulting in request_sock slab object leak. This patch retains the existing behaviour of returning full socks to the caller but it also decrements the child request_socket if one is present before doing so to prevent the leak. Thanks to Curtis Taylor for all the help in diagnosing and testing this. And thanks to Antoine Tenart for the reproducer and patch input. v2 of this patch contains, refactor as per Daniel Borkmann's suggestions to validate RCU flags on the listen socket so that it balances with bpf_sk_release() and update comments as per Martin KaFai Lau's suggestion. One small change to Daniels suggestion, put "sk = sk2" under "if (sk2 != sk)" to avoid an extra instruction. |
No CVSS v4.0
No CVSS v3.0
No CVSS v2
This CVE is not in the KEV list.
Exploit prediction score: < 1% (0.273% probability within 30 days)
Key SSVC decision points have not yet been added.
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux
Linux linux Kernel |
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| Weaknesses | CWE-401 | |
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:5.19:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:5.19:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:5.19:rc3:*:*:*:*:*:* |
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| Vendors & Products |
Linux
Linux linux Kernel |
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Redhat
Redhat enterprise Linux |
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| CPEs | cpe:/a:redhat:enterprise_linux:9 cpe:/o:redhat:enterprise_linux:8 cpe:/o:redhat:enterprise_linux:9 |
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| Vendors & Products |
Redhat
Redhat enterprise Linux |
| Type | Values Removed | Values Added |
|---|---|---|
| References |
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| Metrics |
threat_severity
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cvssV3_1
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| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: bpf: Fix request_sock leak in sk lookup helpers A customer reported a request_socket leak in a Calico cloud environment. We found that a BPF program was doing a socket lookup with takes a refcnt on the socket and that it was finding the request_socket but returning the parent LISTEN socket via sk_to_full_sk() without decrementing the child request socket 1st, resulting in request_sock slab object leak. This patch retains the existing behaviour of returning full socks to the caller but it also decrements the child request_socket if one is present before doing so to prevent the leak. Thanks to Curtis Taylor for all the help in diagnosing and testing this. And thanks to Antoine Tenart for the reproducer and patch input. v2 of this patch contains, refactor as per Daniel Borkmann's suggestions to validate RCU flags on the listen socket so that it balances with bpf_sk_release() and update comments as per Martin KaFai Lau's suggestion. One small change to Daniels suggestion, put "sk = sk2" under "if (sk2 != sk)" to avoid an extra instruction. | |
| Title | bpf: Fix request_sock leak in sk lookup helpers | |
| References |
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Missing Release of Memory after Effective Lifetime