CVE-2022-48921

{"id": "CVE-2022-48921", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 4.7, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.0}]}, "published": "2024-08-22T02:15:08.197", "references": [{"url": "https://git.kernel.org/stable/c/13765de8148f71fa795e0a6607de37c49ea5915a", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/589a954daab5e18399860b6c8ffaeaf79844eb20", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/8f317cd888059c59e2fa924bf4b0957cfa53f78e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/e0bcd6b5779352aed88f2e538a82a39f1a7715bb", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-362"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched/fair: Fix fault in reweight_entity\n\nSyzbot found a GPF in reweight_entity. This has been bisected to\ncommit 4ef0c5c6b5ba (\"kernel/sched: Fix sched_fork() access an invalid\nsched_task_group\")\n\nThere\u00a0is a race between sched_post_fork() and setpriority(PRIO_PGRP)\nwithin a thread group that causes a null-ptr-deref\u00a0in\nreweight_entity() in CFS. The scenario is that the main process spawns\nnumber of new threads, which then call setpriority(PRIO_PGRP, 0, -20),\nwait, and exit. For each of the new threads the copy_process() gets\ninvoked, which adds the new task_struct and calls sched_post_fork()\nfor it.\n\nIn the above scenario there is a possibility that\nsetpriority(PRIO_PGRP) and set_one_prio() will be called for a thread\nin the group that is just being created by copy_process(), and for\nwhich the sched_post_fork() has not been executed yet. This will\ntrigger a null pointer dereference in reweight_entity(),\u00a0as it will\ntry to access the run queue pointer, which hasn't been set.\n\nBefore the mentioned change the cfs_rq pointer for the task has been\nset in sched_fork(), which is called much earlier in copy_process(),\nbefore the new task is added to the thread_group. Now it is done in\nthe sched_post_fork(), which is called after that. To fix the issue\nthe remove the update_load param from the update_load param() function\nand call reweight_task() only if the task flag doesn't have the\nTASK_NEW flag set."}, {"lang": "es", "value": "En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: sched/fair: Solucionar falla en reweight_entity Syzbot encontr\u00f3 un GPF en reweight_entity. Esto se ha dividido en dos para el commit 4ef0c5c6b5ba (\"kernel/sched: Fix sched_fork() accede a un sched_task_group no v\u00e1lido\") Hay una ejecuci\u00f3n entre sched_post_fork() y setpriority(PRIO_PGRP) dentro de un grupo de subprocesos que provoca un null-ptr-deref en reweight_entity () en el SFC. El escenario es que el proceso principal genera una cantidad de subprocesos nuevos, que luego llaman a setpriority(PRIO_PGRP, 0, -20), esperan y salen. Para cada uno de los nuevos subprocesos, se invoca copy_process(), lo que agrega la nueva task_struct y llama a sched_post_fork() para ello. En el escenario anterior existe la posibilidad de que se llame a setpriority(PRIO_PGRP) y set_one_prio() para un subproceso en el grupo que acaba de crear copy_process(), y para el cual sched_post_fork() a\u00fan no se ha ejecutado. Esto desencadenar\u00e1 una desreferencia del puntero nulo en reweight_entity(), ya que intentar\u00e1 acceder al puntero de la cola de ejecuci\u00f3n, que no se ha configurado. Antes del cambio mencionado, el puntero cfs_rq para la tarea se configur\u00f3 en sched_fork(), que se llama mucho antes en copy_process(), antes de que la nueva tarea se agregue al thread_group. Ahora se hace en sched_post_fork(), que se llama despu\u00e9s de eso. Para solucionar el problema, elimine el par\u00e1metro update_load de la funci\u00f3n update_load param() y llame a reweight_task() solo si el indicador de tarea no tiene establecido el indicador TASK_NEW."}], "lastModified": "2024-09-12T12:58:50.660", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "82480749-56E0-4A46-85BF-C3C44B1F8706", "versionEndExcluding": "5.10.137", "versionStartIncluding": "5.10.80"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CC24A46F-AAF0-46A3-9255-D235078D50BC", "versionEndExcluding": "5.15", "versionStartIncluding": "5.14.19"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "61C603D7-C7CD-4505-AF1B-EBFDD4D152AF", "versionEndExcluding": "5.15.27", "versionStartIncluding": "5.15.3"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "B871B667-EDC0-435D-909E-E918D8D90995", "versionEndExcluding": "5.16.13", "versionStartIncluding": "5.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.17:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7BD5F8D9-54FA-4CB0-B4F0-CB0471FDDB2D"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.17:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E6E34B23-78B4-4516-9BD8-61B33F4AC49A"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.17:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "C030FA3D-03F4-4FB9-9DBF-D08E5CAC51AA"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}