{"id":"CVE-2024-50140","state":"PUBLISHED","title":"sched/core: Disable page allocation in task_tick_mm_cid()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched/core: Disable page allocation in task_tick_mm_cid()\n\nWith KASAN and PREEMPT_RT enabled, calling task_work_add() in\ntask_tick_mm_cid() may cause the following splat.\n\n[   63.696416] BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48\n[   63.696416] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 610, name: modprobe\n[   63.696416] preempt_count: 10001, expected: 0\n[   63.696416] RCU nest depth: 1, expected: 1\n\nThis problem is caused by the following call trace.\n\n  sched_tick() [ acquire rq->__lock ]\n   -> task_tick_mm_cid()\n    -> task_work_add()\n     -> __kasan_record_aux_stack()\n      -> kasan_save_stack()\n       -> stack_depot_save_flags()\n        -> alloc_pages_mpol_noprof()\n         -> __alloc_pages_noprof()\n\t  -> get_page_from_freelist()\n\t   -> rmqueue()\n\t    -> rmqueue_pcplist()\n\t     -> __rmqueue_pcplist()\n\t      -> rmqueue_bulk()\n\t       -> rt_spin_lock()\n\nThe rq lock is a raw_spinlock_t. We can't sleep while holding\nit. IOW, we can't call alloc_pages() in stack_depot_save_flags().\n\nThe task_tick_mm_cid() function with its task_work_add() call was\nintroduced by commit 223baf9d17f2 (\"sched: Fix performance regression\nintroduced by mm_cid\") in v6.4 kernel.\n\nFortunately, there is a kasan_record_aux_stack_noalloc() variant that\ncalls stack_depot_save_flags() while not allowing it to allocate\nnew pages.  To allow task_tick_mm_cid() to use task_work without\npage allocation, a new TWAF_NO_ALLOC flag is added to enable calling\nkasan_record_aux_stack_noalloc() instead of kasan_record_aux_stack()\nif set. The task_tick_mm_cid() function is modified to add this new flag.\n\nThe possible downside is the missing stack trace in a KASAN report due\nto new page allocation required when task_work_add_noallloc() is called\nwhich should be rare.","publishedAt":"2024-11-07T09:31:17.379Z","updatedAt":"2026-05-11T20:46:13.274Z","severity":{"score":5.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"223baf9d17f25e2608dbdff7232c095c1e612268","status":"affected","lessThan":"509c29d0d26f68a6f6d0a05cb1a89725237e2b87","versionType":"git"},{"version":"223baf9d17f25e2608dbdff7232c095c1e612268","status":"affected","lessThan":"ce0241ef83eed55f675376e8a3605d23de53d875","versionType":"git"},{"version":"223baf9d17f25e2608dbdff7232c095c1e612268","status":"affected","lessThan":"73ab05aa46b02d96509cb029a8d04fca7bbde8c7","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/task_work.h","kernel/sched/core.c","kernel/task_work.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.4","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.4","versionType":"semver"},{"version":"6.6.59","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.11.6","status":"unaffected","lessThanOrEqual":"6.11.*","versionType":"semver"},{"version":"6.12","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/task_work.h","kernel/sched/core.c","kernel/task_work.c"]}],"references":["https://git.kernel.org/stable/c/509c29d0d26f68a6f6d0a05cb1a89725237e2b87","https://git.kernel.org/stable/c/ce0241ef83eed55f675376e8a3605d23de53d875","https://git.kernel.org/stable/c/73ab05aa46b02d96509cb029a8d04fca7bbde8c7"],"weaknesses":[],"ingestedAt":"2026-10-29T20:07:56.516Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2024/50xxx/CVE-2024-50140.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2024-50140","state":"PUBLISHED","datePublished":"2024-11-07T09:31:17.379Z","dateUpdated":"2026-05-11T20:46:13.274Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-10-21T19:36:19.956Z"},"containers":{"cna":{"title":"sched/core: Disable page allocation in task_tick_mm_cid()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched/core: Disable page allocation in task_tick_mm_cid()\n\nWith KASAN and PREEMPT_RT enabled, calling task_work_add() in\ntask_tick_mm_cid() may cause the following splat.\n\n[   63.696416] BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48\n[   63.696416] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 610, name: modprobe\n[   63.696416] preempt_count: 10001, expected: 0\n[   63.696416] RCU nest depth: 1, expected: 1\n\nThis problem is caused by the following call trace.\n\n  sched_tick() [ acquire rq->__lock ]\n   -> task_tick_mm_cid()\n    -> task_work_add()\n     -> __kasan_record_aux_stack()\n      -> kasan_save_stack()\n       -> stack_depot_save_flags()\n        -> alloc_pages_mpol_noprof()\n         -> __alloc_pages_noprof()\n\t  -> get_page_from_freelist()\n\t   -> rmqueue()\n\t    -> rmqueue_pcplist()\n\t     -> __rmqueue_pcplist()\n\t      -> rmqueue_bulk()\n\t       -> rt_spin_lock()\n\nThe rq lock is a raw_spinlock_t. We can't sleep while holding\nit. IOW, we can't call alloc_pages() in stack_depot_save_flags().\n\nThe task_tick_mm_cid() function with its task_work_add() call was\nintroduced by commit 223baf9d17f2 (\"sched: Fix performance regression\nintroduced by mm_cid\") in v6.4 kernel.\n\nFortunately, there is a kasan_record_aux_stack_noalloc() variant that\ncalls stack_depot_save_flags() while not allowing it to allocate\nnew pages.  To allow task_tick_mm_cid() to use task_work without\npage allocation, a new TWAF_NO_ALLOC flag is added to enable calling\nkasan_record_aux_stack_noalloc() instead of kasan_record_aux_stack()\nif set. The task_tick_mm_cid() function is modified to add this new flag.\n\nThe possible downside is the missing stack trace in a KASAN report due\nto new page allocation required when task_work_add_noallloc() is called\nwhich should be rare."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"223baf9d17f25e2608dbdff7232c095c1e612268","status":"affected","lessThan":"509c29d0d26f68a6f6d0a05cb1a89725237e2b87","versionType":"git"},{"version":"223baf9d17f25e2608dbdff7232c095c1e612268","status":"affected","lessThan":"ce0241ef83eed55f675376e8a3605d23de53d875","versionType":"git"},{"version":"223baf9d17f25e2608dbdff7232c095c1e612268","status":"affected","lessThan":"73ab05aa46b02d96509cb029a8d04fca7bbde8c7","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/task_work.h","kernel/sched/core.c","kernel/task_work.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.4","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.4","versionType":"semver"},{"version":"6.6.59","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.11.6","status":"unaffected","lessThanOrEqual":"6.11.*","versionType":"semver"},{"version":"6.12","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/linux/task_work.h","kernel/sched/core.c","kernel/task_work.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/509c29d0d26f68a6f6d0a05cb1a89725237e2b87"},{"url":"https://git.kernel.org/stable/c/ce0241ef83eed55f675376e8a3605d23de53d875"},{"url":"https://git.kernel.org/stable/c/73ab05aa46b02d96509cb029a8d04fca7bbde8c7"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T20:46:13.274Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.4","versionEndExcluding":"6.6.59"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.4","versionEndExcluding":"6.11.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.4","versionEndExcluding":"6.12"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":5.5,"attackVector":"LOCAL","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"id":"CVE-2024-50140","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2025-10-01T20:21:10.724441Z"}}}],"problemTypes":[{"descriptions":[{"lang":"en","type":"CWE","description":"CWE-noinfo Not enough information"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-10-01T20:27:14.428Z"}}]}}}