{"cve":"CVE-2022-49196","nvd":{"published":"2025-02-26T07:00:56.677","modified":"2026-06-17T05:17:21.210","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/pseries: Fix use after free in remove_phb_dynamic()\n\nIn remove_phb_dynamic() we use &phb->io_resource, after we've called\ndevice_unregister(&host_bridge->dev). But the unregister may have freed\nphb, because pcibios_free_controller_deferred() is the release function\nfor the host_bridge.\n\nIf there are no outstanding references when we call device_unregister()\nthen phb will be freed out from under us.\n\nThis has gone mainly unnoticed, but with slub_debug and page_poison\nenabled it can lead to a crash:\n\n  PID: 7574   TASK: c0000000d492cb80  CPU: 13  COMMAND: \"drmgr\"\n   #0 [c0000000e4f075a0] crash_kexec at c00000000027d7dc\n   #1 [c0000000e4f075d0] oops_end at c000000000029608\n   #2 [c0000000e4f07650] __bad_page_fault at c0000000000904b4\n   #3 [c0000000e4f076c0] do_bad_slb_fault at c00000000009a5a8\n   #4 [c0000000e4f076f0] data_access_slb_common_virt at c000000000008b30\n   Data SLB Access [380] exception frame:\n   R0:  c000000000167250    R1:  c0000000e4f07a00    R2:  c000000002a46100\n   R3:  c000000002b39ce8    R4:  00000000000000c0    R5:  00000000000000a9\n   R6:  3894674d000000c0    R7:  0000000000000000    R8:  00000000000000ff\n   R9:  0000000000000100    R10: 6b6b6b6b6b6b6b6b    R11: 0000000000008000\n   R12: c00000000023da80    R13: c0000009ffd38b00    R14: 0000000000000000\n   R15: 000000011c87f0f0    R16: 0000000000000006    R17: 0000000000000003\n   R18: 0000000000000002    R19: 0000000000000004    R20: 0000000000000005\n   R21: 000000011c87ede8    R22: 000000011c87c5a8    R23: 000000011c87d3a0\n   R24: 0000000000000000    R25: 0000000000000001    R26: c0000000e4f07cc8\n   R27: c00000004d1cc400    R28: c0080000031d00e8    R29: c00000004d23d800\n   R30: c00000004d1d2400    R31: c00000004d1d2540\n   NIP: c000000000167258    MSR: 8000000000009033    OR3: c000000000e9f474\n   CTR: 0000000000000000    LR:  c000000000167250    XER: 0000000020040003\n   CCR: 0000000024088420    MQ:  0000000000000000    DAR: 6b6b6b6b6b6b6ba3\n   DSISR: c0000000e4f07920     Syscall Result: fffffffffffffff2\n   [NIP  : release_resource+56]\n   [LR   : release_resource+48]\n   #5 [c0000000e4f07a00] release_resource at c000000000167258  (unreliable)\n   #6 [c0000000e4f07a30] remove_phb_dynamic at c000000000105648\n   #7 [c0000000e4f07ab0] dlpar_remove_slot at c0080000031a09e8 [rpadlpar_io]\n   #8 [c0000000e4f07b50] remove_slot_store at c0080000031a0b9c [rpadlpar_io]\n   #9 [c0000000e4f07be0] kobj_attr_store at c000000000817d8c\n  #10 [c0000000e4f07c00] sysfs_kf_write at c00000000063e504\n  #11 [c0000000e4f07c20] kernfs_fop_write_iter at c00000000063d868\n  #12 [c0000000e4f07c70] new_sync_write at c00000000054339c\n  #13 [c0000000e4f07d10] vfs_write at c000000000546624\n  #14 [c0000000e4f07d60] ksys_write at c0000000005469f4\n  #15 [c0000000e4f07db0] system_call_exception at c000000000030840\n  #16 [c0000000e4f07e10] system_call_vectored_common at c00000000000c168\n\nTo avoid it, we can take a reference to the host_bridge->dev until we're\ndone using phb. Then when we drop the reference the phb will be freed.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-416"],"references":["https://git.kernel.org/stable/c/33d39efb61a84e055ca2386157d39ebbdf6b7d31","https://git.kernel.org/stable/c/403f9e0bc5535a0a5184d1352fa3a70e6ffacb6f","https://git.kernel.org/stable/c/895ca4ae1f72e0a0160ab162723e59c9f265ec93","https://git.kernel.org/stable/c/fe2640bd7a62f1f7c3f55fbda31084085075bc30"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:59:48.811064707+00:00"},"epss":{"cve":"CVE-2022-49196","score":0.00275,"percentile":0.19955,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}