| { |
| "containers": { |
| "cna": { |
| "providerMetadata": { |
| "orgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038" |
| }, |
| "descriptions": [ |
| { |
| "lang": "en", |
| "value": "In the Linux kernel, the following vulnerability has been resolved:\n\npfifo_tail_enqueue: Drop new packet when sch->limit == 0\n\nExpected behaviour:\nIn case we reach scheduler's limit, pfifo_tail_enqueue() will drop a\npacket in scheduler's queue and decrease scheduler's qlen by one.\nThen, pfifo_tail_enqueue() enqueue new packet and increase\nscheduler's qlen by one. Finally, pfifo_tail_enqueue() return\n`NET_XMIT_CN` status code.\n\nWeird behaviour:\nIn case we set `sch->limit == 0` and trigger pfifo_tail_enqueue() on a\nscheduler that has no packet, the 'drop a packet' step will do nothing.\nThis means the scheduler's qlen still has value equal 0.\nThen, we continue to enqueue new packet and increase scheduler's qlen by\none. In summary, we can leverage pfifo_tail_enqueue() to increase qlen by\none and return `NET_XMIT_CN` status code.\n\nThe problem is:\nLet's say we have two qdiscs: Qdisc_A and Qdisc_B.\n - Qdisc_A's type must have '->graft()' function to create parent/child relationship.\n Let's say Qdisc_A's type is `hfsc`. Enqueue packet to this qdisc will trigger `hfsc_enqueue`.\n - Qdisc_B's type is pfifo_head_drop. Enqueue packet to this qdisc will trigger `pfifo_tail_enqueue`.\n - Qdisc_B is configured to have `sch->limit == 0`.\n - Qdisc_A is configured to route the enqueued's packet to Qdisc_B.\n\nEnqueue packet through Qdisc_A will lead to:\n - hfsc_enqueue(Qdisc_A) -> pfifo_tail_enqueue(Qdisc_B)\n - Qdisc_B->q.qlen += 1\n - pfifo_tail_enqueue() return `NET_XMIT_CN`\n - hfsc_enqueue() check for `NET_XMIT_SUCCESS` and see `NET_XMIT_CN` => hfsc_enqueue() don't increase qlen of Qdisc_A.\n\nThe whole process lead to a situation where Qdisc_A->q.qlen == 0 and Qdisc_B->q.qlen == 1.\nReplace 'hfsc' with other type (for example: 'drr') still lead to the same problem.\nThis violate the design where parent's qlen should equal to the sum of its childrens'qlen.\n\nBug impact: This issue can be used for user->kernel privilege escalation when it is reachable." |
| } |
| ], |
| "affected": [ |
| { |
| "product": "Linux", |
| "vendor": "Linux", |
| "defaultStatus": "unaffected", |
| "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", |
| "programFiles": [ |
| "net/sched/sch_fifo.c" |
| ], |
| "versions": [ |
| { |
| "version": "57dbb2d83d100ea601c54fe129bfde0678db5dee", |
| "lessThan": "78285b53266d6d51fa4ff504a23df03852eba84e", |
| "status": "affected", |
| "versionType": "git" |
| }, |
| { |
| "version": "57dbb2d83d100ea601c54fe129bfde0678db5dee", |
| "lessThan": "7a9723ec27aff5674f1fd4934608937f1d650980", |
| "status": "affected", |
| "versionType": "git" |
| }, |
| { |
| "version": "57dbb2d83d100ea601c54fe129bfde0678db5dee", |
| "lessThan": "a56a6e8589a9b98d8171611fbcc1e45a15fd2455", |
| "status": "affected", |
| "versionType": "git" |
| }, |
| { |
| "version": "57dbb2d83d100ea601c54fe129bfde0678db5dee", |
| "lessThan": "020ecb76812a0526f4130ab5aeb6dc7c773e7ab9", |
| "status": "affected", |
| "versionType": "git" |
| }, |
| { |
| "version": "57dbb2d83d100ea601c54fe129bfde0678db5dee", |
| "lessThan": "79a955ea4a2e5ddf4a36328959de0de496419888", |
| "status": "affected", |
| "versionType": "git" |
| }, |
| { |
| "version": "57dbb2d83d100ea601c54fe129bfde0678db5dee", |
| "lessThan": "e40cb34b7f247fe2e366fd192700d1b4f38196ca", |
| "status": "affected", |
| "versionType": "git" |
| }, |
| { |
| "version": "57dbb2d83d100ea601c54fe129bfde0678db5dee", |
| "lessThan": "b6a079c3b6f95378f26e2aeda520cb3176f7067b", |
| "status": "affected", |
| "versionType": "git" |
| }, |
| { |
| "version": "57dbb2d83d100ea601c54fe129bfde0678db5dee", |
| "lessThan": "647cef20e649c576dff271e018d5d15d998b629d", |
| "status": "affected", |
| "versionType": "git" |
| } |
| ] |
| }, |
| { |
| "product": "Linux", |
| "vendor": "Linux", |
| "defaultStatus": "affected", |
| "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", |
| "programFiles": [ |
| "net/sched/sch_fifo.c" |
| ], |
| "versions": [ |
| { |
| "version": "2.6.34", |
| "status": "affected" |
| }, |
| { |
| "version": "0", |
| "lessThan": "2.6.34", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "5.4.291", |
| "lessThanOrEqual": "5.4.*", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "5.10.235", |
| "lessThanOrEqual": "5.10.*", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "5.15.179", |
| "lessThanOrEqual": "5.15.*", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "6.1.130", |
| "lessThanOrEqual": "6.1.*", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "6.6.83", |
| "lessThanOrEqual": "6.6.*", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "6.12.14", |
| "lessThanOrEqual": "6.12.*", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "6.13.3", |
| "lessThanOrEqual": "6.13.*", |
| "status": "unaffected", |
| "versionType": "semver" |
| }, |
| { |
| "version": "6.14", |
| "lessThanOrEqual": "*", |
| "status": "unaffected", |
| "versionType": "original_commit_for_fix" |
| } |
| ] |
| } |
| ], |
| "cpeApplicability": [ |
| { |
| "nodes": [ |
| { |
| "operator": "OR", |
| "negate": false, |
| "cpeMatch": [ |
| { |
| "vulnerable": true, |
| "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", |
| "versionStartIncluding": "2.6.34", |
| "versionEndExcluding": "5.4.291" |
| }, |
| { |
| "vulnerable": true, |
| "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", |
| "versionStartIncluding": "2.6.34", |
| "versionEndExcluding": "5.10.235" |
| }, |
| { |
| "vulnerable": true, |
| "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", |
| "versionStartIncluding": "2.6.34", |
| "versionEndExcluding": "5.15.179" |
| }, |
| { |
| "vulnerable": true, |
| "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", |
| "versionStartIncluding": "2.6.34", |
| "versionEndExcluding": "6.1.130" |
| }, |
| { |
| "vulnerable": true, |
| "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", |
| "versionStartIncluding": "2.6.34", |
| "versionEndExcluding": "6.6.83" |
| }, |
| { |
| "vulnerable": true, |
| "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", |
| "versionStartIncluding": "2.6.34", |
| "versionEndExcluding": "6.12.14" |
| }, |
| { |
| "vulnerable": true, |
| "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", |
| "versionStartIncluding": "2.6.34", |
| "versionEndExcluding": "6.13.3" |
| }, |
| { |
| "vulnerable": true, |
| "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", |
| "versionStartIncluding": "2.6.34", |
| "versionEndExcluding": "6.14" |
| } |
| ] |
| } |
| ] |
| } |
| ], |
| "references": [ |
| { |
| "url": "https://git.kernel.org/stable/c/78285b53266d6d51fa4ff504a23df03852eba84e" |
| }, |
| { |
| "url": "https://git.kernel.org/stable/c/7a9723ec27aff5674f1fd4934608937f1d650980" |
| }, |
| { |
| "url": "https://git.kernel.org/stable/c/a56a6e8589a9b98d8171611fbcc1e45a15fd2455" |
| }, |
| { |
| "url": "https://git.kernel.org/stable/c/020ecb76812a0526f4130ab5aeb6dc7c773e7ab9" |
| }, |
| { |
| "url": "https://git.kernel.org/stable/c/79a955ea4a2e5ddf4a36328959de0de496419888" |
| }, |
| { |
| "url": "https://git.kernel.org/stable/c/e40cb34b7f247fe2e366fd192700d1b4f38196ca" |
| }, |
| { |
| "url": "https://git.kernel.org/stable/c/b6a079c3b6f95378f26e2aeda520cb3176f7067b" |
| }, |
| { |
| "url": "https://git.kernel.org/stable/c/647cef20e649c576dff271e018d5d15d998b629d" |
| } |
| ], |
| "title": "pfifo_tail_enqueue: Drop new packet when sch->limit == 0", |
| "x_generator": { |
| "engine": "bippy-1.2.0" |
| } |
| } |
| }, |
| "cveMetadata": { |
| "assignerOrgId": "f4215fc3-5b6b-47ff-a258-f7189bd81038", |
| "cveID": "CVE-2025-21702", |
| "requesterUserId": "gregkh@kernel.org", |
| "serial": "1", |
| "state": "PUBLISHED" |
| }, |
| "dataType": "CVE_RECORD", |
| "dataVersion": "5.0" |
| } |
