CVE-2026-90072
CVE.org · Published
- Record status
- Published
- Identifier year (not publication year)
- 2026
- Source publication
- Source updated
- Imported by cveboard
- Source snapshot
- cve_2026-10-24_midnight_baseline ·
CNA source text (English)
net/sched: sfq: clamp quantum to avoid signed overflow soft lockup
In the Linux kernel, the following vulnerability has been resolved: net/sched: sfq: clamp quantum to avoid signed overflow soft lockup sfq_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) (unsigned). A device with a huge MTU (e.g. dummy with max_mtu == 0 accepting MTU 2147483634) makes psched_mtu() return 0x80000000, so slot->allot = INT_MIN and INT_MIN + INT_MIN toggles between INT_MIN and 0 forever, spinning sfq_dequeue() under the qdisc lock. Clamp the quantum to [256, 1 << 20] so the refill loop terminates. The lower bound also covers q->quantum == 0 (psched_mtu() returning 0), which spins sfq_dequeue() identically. sfq_change() already rejects a negative quantum, so only the init path was exposed. Conditions to recreate the bug: a device whose MTU (plus hard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy device with max_mtu == 0 accepting MTU 2147483634). Requires CAP_NET_ADMIN in a user namespace.
Scoped product and version facts
Fix information unknown; no fixed version is derived here. Missing information does not prove that no fix exists.
Exploitation unknown; this catalogue does not assess exploitation.
Linux
- Vendor
- Linux
- Product
- Linux
- Platforms
- Unknown
- Default status
unaffected
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 | affected | git | 86799499585af06a9431c9e7782658667bd62650 | Unavailable | None listed |
| 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 | affected | git | 2017c355a5a1af77736cd1739fe922f69b5652dc | Unavailable | None listed |
| 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 | affected | git | 6581a82bf08ba5d4e2a6d4e3080df43315b296c4 | Unavailable | None listed |
| 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 | affected | git | 9d782c662879c3adaaca30e05c36910ad11b9e54 | Unavailable | None listed |
| 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 | affected | git | d72dbdfaeb5b9b8d884e0e036c3442754379ef74 | Unavailable | None listed |
| 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 | affected | git | aeb8196ecb95146e3410f635628e6cd47352b3e5 | Unavailable | None listed |
| 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 | affected | git | da16c31517cd2c06bb2c78c73e91ae192c01c426 | Unavailable | None listed |
| 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 | affected | git | 816e90057ab1879562a5b7cc688e35bb9027ae97 | Unavailable | None listed |
Linux
- Vendor
- Linux
- Product
- Linux
- Platforms
- Unknown
- Default status
affected
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 2.6.12 | affected | Unavailable | Unavailable | Unavailable | None listed |
| 0 | unaffected | semver | 2.6.12 | Unavailable | None listed |
| 5.10.270 | unaffected | semver | Unavailable | 5.10.* | None listed |
| 5.15.221 | unaffected | semver | Unavailable | 5.15.* | None listed |
| 6.1.188 | unaffected | semver | Unavailable | 6.1.* | None listed |
| 6.6.157 | unaffected | semver | Unavailable | 6.6.* | None listed |
| 6.12.110 | unaffected | semver | Unavailable | 6.12.* | None listed |
| 6.18.52 | unaffected | semver | Unavailable | 6.18.* | None listed |
| 7.2.6 | unaffected | semver | Unavailable | 7.2.* | None listed |
| 7.3 | unaffected | original_commit_for_fix | Unavailable | * | None listed |