{"id":"CVE-2022-50103","title":"sched, cpuset: Fix dl_cpu_busy() panic due to empty cs->cpus_allowed","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nsched, cpuset: Fix dl_cpu_busy() panic due to empty cs->cpus_allowed\n\nWith cgroup v2, the cpuset's cpus_allowed mask can be empty indicating\nthat the cpuset will just u…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 7f51412a415d87ea8598d14722fb31e4f5701257 < 336626564b58071b8980a4e6a31a8f5d92705d9b","Linux >= 7f51412a415d87ea8598d14722fb31e4f5701257 < 147f66d22f58712dce7ccdd6a1f6cb3ee8042df4","Linux >= 7f51412a415d87ea8598d14722fb31e4f5701257 < 357f3f0e522a6ce1ce4a571cb780d9861d53bec7","Linux >= 7f51412a415d87ea8598d14722fb31e4f5701257 < f56607b44c9896e51678a7e8cdd3a5479f4b4548","Linux >= 7f51412a415d87ea8598d14722fb31e4f5701257 < b6e8d40d43ae4dec00c8fea2593eeea3114b8f44","Linux 3.19"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-05T19:54:25.132451Z"},"published":"2025-06-18","updated":"2026-11-05","sourceUpdated":"2026-11-05T20:00:16.912Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2022-50103","references":[{"url":"https://git.kernel.org/stable/c/336626564b58071b8980a4e6a31a8f5d92705d9b"},{"url":"https://git.kernel.org/stable/c/147f66d22f58712dce7ccdd6a1f6cb3ee8042df4"},{"url":"https://git.kernel.org/stable/c/357f3f0e522a6ce1ce4a571cb780d9861d53bec7"},{"url":"https://git.kernel.org/stable/c/f56607b44c9896e51678a7e8cdd3a5479f4b4548"},{"url":"https://git.kernel.org/stable/c/b6e8d40d43ae4dec00c8fea2593eeea3114b8f44"}],"tags":["cve.org"],"epss":0.00198,"epssPercentile":0.0966,"ingestedAt":"2026-11-05T22:38:31.660Z","slug":"CVE-2022-50103","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nsched, cpuset: Fix dl_cpu_busy() panic due to empty cs->cpus_allowed\n\nWith cgroup v2, the cpuset's cpus_allowed mask can be empty indicating\nthat the cpuset will just use the effective CPUs of its parent. So\ncpuset_can_attach() can call task_can_attach() with an empty mask.\nThis can lead to cpumask_any_and() returns nr_cpu_ids causing the call\nto dl_bw_of() to crash due to percpu value access of an out of bound\nCPU value. For example:\n\n\t[80468.182258] BUG: unable to handle page fault for address: ffffffff8b6648b0\n\t  :\n\t[80468.191019] RIP: 0010:dl_cpu_busy+0x30/0x2b0\n\t  :\n\t[80468.207946] Call Trace:\n\t[80468.208947]  cpuset_can_attach+0xa0/0x140\n\t[80468.209953]  cgroup_migrate_execute+0x8c/0x490\n\t[80468.210931]  cgroup_update_dfl_csses+0x254/0x270\n\t[80468.211898]  cgroup_subtree_control_write+0x322/0x400\n\t[80468.212854]  kernfs_fop_write_iter+0x11c/0x1b0\n\t[80468.213777]  new_sync_write+0x11f/0x1b0\n\t[80468.214689]  vfs_write+0x1eb/0x280\n\t[80468.215592]  ksys_write+0x5f/0xe0\n\t[80468.216463]  do_syscall_64+0x5c/0x80\n\t[80468.224287]  entry_SYSCALL_64_after_hwframe+0x44/0xae\n\nFix that by using effective_cpus instead. For cgroup v1, effective_cpus\nis the same as cpus_allowed. For v2, effective_cpus is the real cpumask\nto be used by tasks within the cpuset anyway.\n\nAlso update task_can_attach()'s 2nd argument name to cs_effective_cpus to\nreflect the change. In addition, a check is added to task_can_attach()\nto guard against the possibility that cpumask_any_and() may return a\nvalue >= nr_cpu_ids.\n\n## Affected\n\n- `Linux >= 7f51412a415d87ea8598d14722fb31e4f5701257 < 336626564b58071b8980a4e6a31a8f5d92705d9b`\n- `Linux >= 7f51412a415d87ea8598d14722fb31e4f5701257 < 147f66d22f58712dce7ccdd6a1f6cb3ee8042df4`\n- `Linux >= 7f51412a415d87ea8598d14722fb31e4f5701257 < 357f3f0e522a6ce1ce4a571cb780d9861d53bec7`\n- `Linux >= 7f51412a415d87ea8598d14722fb31e4f5701257 < f56607b44c9896e51678a7e8cdd3a5479f4b4548`\n- `Linux >= 7f51412a415d87ea8598d14722fb31e4f5701257 < b6e8d40d43ae4dec00c8fea2593eeea3114b8f44`\n- `Linux 3.19`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}