net/sched: sch_codel: Do not call qdisc_tree_reduce_backlog during peek before restoring qlen
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_codel: Do not call qdisc_tree_reduce_backlog during peek before restoring qlen Whenever codel drops packets during peek, it calls qdisc_tree_reduce_backlog. An issue arises because it calls qdisc_tree_reduce_backlog before it reincrements the qlen. If qlen drops to zero, but peek returns an skb, the parent's qlen_notify callback will be executed even though codel still has 1 packet on the queue and, thus, will mistakenly deactivate the parent's class causing issues like a wild memory access when qfq has codel as a child: [ 36.339843][ T370] Oops: general protection fault, probably for non-canonical address 0xfbd59c0000000024: 0000 [#1] SMP KASAN NOPTI [ 36.340408][ T370] KASAN: maybe wild-memory-access in range [0xdead000000000120-0xdead000000000127] [ 36.340737][ T370] CPU: 2 UID: 0 PID: 370 Comm: tc Not tainted 7.1.0-rc5-00287-g66e13b626592 #87 PREEMPT(full) [ 36.341113][ T370] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 36.341357][ T370] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:1029 (discriminator 2) include/linux/list.h:1043 (discriminator 2) net/sched/sch_qfq.c:1369 (discriminator 2) net/sched/sch_qfq.c:1395 (discriminator 2)) sch_qfq [ 36.342221][ T370] RSP: 0018:ffff8881100ef370 EFLAGS: 00010216 [ 36.342422][ T370] RAX: 0000000000000000 RBX: ffff8881058a9568 RCX: dffffc0000000000 [ 36.342664][ T370] RDX: 1ffff11021064dc3 RSI: ffff888108326e00 RDI: dffffc0000000000 [ 36.
CVE-2026-74267
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-74267
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "cc71a757da78dd4aa1b4a9b19cb011833730ccf2",
"lessThan": "bb9cfd874ee884117b33e92a002b9a45b48202f4",
"versionType": "git"
},
{
"status": "affected",
"version": "eda741fe155ddf5ecd2dd3bfbd4fc3c0c7dbb450",
"lessThan": "7a05af7f58566682b73578b72ca8e53a268c43bd",
"versionType": "git"
},
{
"status": "affected",
"version": "829c49b6b2ff45b043739168fd1245e4e1a91a30",
"lessThan": "eba49fd85995a3851c597fa2d214f8d21736e1d8",
"versionType": "git"
},
{
"status": "affected",
"version": "2f9761a94bae33d26e6a81b31b36e7d776d93dc1",
"lessThan": "e8c6dbadf139cb14ea6ed14add6ed6e88504dedd",
"versionType": "git"
},
{
"status": "affected",
"version": "4d55144b12e742404bb3f8fee6038bafbf45619d",
"lessThan": "e4615aa6bb7802944ae790cb4b3ef8c1b7491af3",
"versionType": "git"
},
{
"status": "affected",
"version": "342debc12183b51773b3345ba267e9263bdfaaef",
"lessThan": "755108bb7a5083e911294c416cfea605dc75632f",
"versionType": "git"
},
{
"status": "affected",
"version": "342debc12183b51773b3345ba267e9263bdfaaef",
"lessThan": "91e0a793a72374c20ab31a40ccec21373e82e973",
"versionType": "git"
},
{
"status": "affected",
"version": "342debc12183b51773b3345ba267e9263bdfaaef",
"lessThan": "52f1da34c9f4d5bdc1e8b44242da5c7ba8db85f3",
"versionType": "git"
},
{
"status": "affected",
"version": "7a742a9506849d1c1aa71e36c89855ceddc7d58e",
"versionType": "git"
},
{
"status": "affected",
"version": "e73c838c80dccb9e4f19becc11d9f3cb4a27d483",
"versionType": "git"
},
{
"status": "affected",
"version": "a57fe60ef4cf96bfbb6b58397ec28bdb5a5c6b31",
"versionType": "git"
},
{
"status": "affected",
"version": "5.10.241",
"lessThan": "5.10.261",
"versionType": "semver"
},
{
"status": "affected",
"version": "5.15.190",
"lessThan": "5.15.212",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.1.135",
"lessThan": "6.1.178",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.6.88",
"lessThan": "6.6.145",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.12.24",
"lessThan": "6.12.97",
"versionType": "semver"
},
{
"status": "affected",
"version": "5.4.297",
"lessThan": "5.5",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.13.12",
"lessThan": "6.14",
"versionType": "semver"
},
{
"status": "affected",
"version": "6.14.3",
"lessThan": "6.15",
"versionType": "semver"
}
],
"programFiles": [
"net/sched/sch_codel.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.15"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.15",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.261",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.212",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.178",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.145",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.97",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.40",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/sched/sch_codel.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-74267
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #33073 · Revision 1
- Added to Heist Feed
- Publisher date