{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2025-68780", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-12-24T10:30:51.036Z", "datePublished": "2026-01-13T15:28:55.483Z", "dateUpdated": "2026-01-13T15:28:55.483Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-01-13T15:28:55.483Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched/deadline: only set free_cpus for online runqueues\n\nCommit 16b269436b72 (\"sched/deadline: Modify cpudl::free_cpus\nto reflect rd->online\") introduced the cpudl_set/clear_freecpu\nfunctions to allow the cpu_dl::free_cpus mask to be manipulated\nby the deadline scheduler class rq_on/offline callbacks so the\nmask would also reflect this state.\n\nCommit 9659e1eeee28 (\"sched/deadline: Remove cpu_active_mask\nfrom cpudl_find()\") removed the check of the cpu_active_mask to\nsave some processing on the premise that the cpudl::free_cpus\nmask already reflected the runqueue online state.\n\nUnfortunately, there are cases where it is possible for the\ncpudl_clear function to set the free_cpus bit for a CPU when the\ndeadline runqueue is offline. When this occurs while a CPU is\nconnected to the default root domain the flag may retain the bad\nstate after the CPU has been unplugged. Later, a different CPU\nthat is transitioning through the default root domain may push a\ndeadline task to the powered down CPU when cpudl_find sees its\nfree_cpus bit is set. If this happens the task will not have the\nopportunity to run.\n\nOne example is outlined here:\nhttps://lore.kernel.org/lkml/20250110233010.2339521-1-opendmb@gmail.com\n\nAnother occurs when the last deadline task is migrated from a\nCPU that has an offlined runqueue. The dequeue_task member of\nthe deadline scheduler class will eventually call cpudl_clear\nand set the free_cpus bit for the CPU.\n\nThis commit modifies the cpudl_clear function to be aware of the\nonline state of the deadline runqueue so that the free_cpus mask\ncan be updated appropriately.\n\nIt is no longer necessary to manage the mask outside of the\ncpudl_set/clear functions so the cpudl_set/clear_freecpu\nfunctions are removed. In addition, since the free_cpus mask is\nnow only updated under the cpudl lock the code was changed to\nuse the non-atomic __cpumask functions."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/sched/cpudeadline.c", "kernel/sched/cpudeadline.h", "kernel/sched/deadline.c"], "versions": [{"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "fb36846cbcc936954f2ad2bffdff13d16c0be08a", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "91e448e69aca4bb0ba2e998eb3e555644db7322b", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "dbc61834b0412435df21c71410562d933e4eba49", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "3ed049fbfb4d75b4e0b8ab54c934f485129d5dc8", "status": "affected", "versionType": "git"}, {"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2", "lessThan": "382748c05e58a9f1935f5a653c352422375566ea", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["kernel/sched/cpudeadline.c", "kernel/sched/cpudeadline.h", "kernel/sched/deadline.c"], "versions": [{"version": "6.1.160", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.120", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.64", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.3", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19-rc1", "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:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.1.160"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.6.120"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.12.64"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.18.3"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionEndExcluding": "6.19-rc1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/fb36846cbcc936954f2ad2bffdff13d16c0be08a"}, {"url": "https://git.kernel.org/stable/c/91e448e69aca4bb0ba2e998eb3e555644db7322b"}, {"url": "https://git.kernel.org/stable/c/dbc61834b0412435df21c71410562d933e4eba49"}, {"url": "https://git.kernel.org/stable/c/3ed049fbfb4d75b4e0b8ab54c934f485129d5dc8"}, {"url": "https://git.kernel.org/stable/c/382748c05e58a9f1935f5a653c352422375566ea"}], "title": "sched/deadline: only set free_cpus for online runqueues", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched/deadline: only set free_cpus for online runqueues\n\nCommit 16b269436b72 (\"sched/deadline: Modify cpudl::free_cpus\nto reflect rd->online\") introduced the cpudl_set/clear_freecpu\nfunctions to allow the cpu_dl::free_cpus mask to be manipulated\nby the deadline scheduler class rq_on/offline callbacks so the\nmask would also reflect this state.\n\nCommit 9659e1eeee28 (\"sched/deadline: Remove cpu_active_mask\nfrom cpudl_find()\") removed the check of the cpu_active_mask to\nsave some processing on the premise that the cpudl::free_cpus\nmask already reflected the runqueue online state.\n\nUnfortunately, there are cases where it is possible for the\ncpudl_clear function to set the free_cpus bit for a CPU when the\ndeadline runqueue is offline. When this occurs while a CPU is\nconnected to the default root domain the flag may retain the bad\nstate after the CPU has been unplugged. Later, a different CPU\nthat is transitioning through the default root domain may push a\ndeadline task to the powered down CPU when cpudl_find sees its\nfree_cpus bit is set. If this happens the task will not have the\nopportunity to run.\n\nOne example is outlined here:\nhttps://lore.kernel.org/lkml/20250110233010.2339521-1-opendmb@gmail.com\n\nAnother occurs when the last deadline task is migrated from a\nCPU that has an offlined runqueue. The dequeue_task member of\nthe deadline scheduler class will eventually call cpudl_clear\nand set the free_cpus bit for the CPU.\n\nThis commit modifies the cpudl_clear function to be aware of the\nonline state of the deadline runqueue so that the free_cpus mask\ncan be updated appropriately.\n\nIt is no longer necessary to manage the mask outside of the\ncpudl_set/clear functions so the cpudl_set/clear_freecpu\nfunctions are removed. In addition, since the free_cpus mask is\nnow only updated under the cpudl lock the code was changed to\nuse the non-atomic __cpumask functions."}], "id": "CVE-2025-68780", "lastModified": "2026-01-13T16:15:57.657", "metrics": {}, "published": "2026-01-13T16:15:57.657", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/382748c05e58a9f1935f5a653c352422375566ea"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/3ed049fbfb4d75b4e0b8ab54c934f485129d5dc8"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/91e448e69aca4bb0ba2e998eb3e555644db7322b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/dbc61834b0412435df21c71410562d933e4eba49"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/fb36846cbcc936954f2ad2bffdff13d16c0be08a"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{}