{"cve":"CVE-2022-50738","nvd":{"published":"2025-12-24T13:16:00.503","modified":"2026-06-17T05:24:05.663","status":"Deferred","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nvhost-vdpa: fix an iotlb memory leak\n\nBefore commit 3d5698793897 (\"vhost-vdpa: introduce asid based IOTLB\")\nwe called vhost_vdpa_iotlb_unmap(v, iotlb, 0ULL, 0ULL - 1) during\nrelease to free all the resources allocated when processing user IOTLB\nmessages through vhost_vdpa_process_iotlb_update().\nThat commit changed the handling of IOTLB a bit, and we accidentally\nremoved some code called during the release.\n\nWe partially fixed this with commit 037d4305569a (\"vhost-vdpa: call\nvhost_vdpa_cleanup during the release\") but a potential memory leak is\nstill there as showed by kmemleak if the application does not send\nVHOST_IOTLB_INVALIDATE or crashes:\n\n  unreferenced object 0xffff888007fbaa30 (size 16):\n    comm \"blkio-bench\", pid 914, jiffies 4294993521 (age 885.500s)\n    hex dump (first 16 bytes):\n      40 73 41 07 80 88 ff ff 00 00 00 00 00 00 00 00  @sA.............\n    backtrace:\n      [<0000000087736d2a>] kmem_cache_alloc_trace+0x142/0x1c0\n      [<0000000060740f50>] vhost_vdpa_process_iotlb_msg+0x68c/0x901 [vhost_vdpa]\n      [<0000000083e8e205>] vhost_chr_write_iter+0xc0/0x4a0 [vhost]\n      [<000000008f2f414a>] vhost_vdpa_chr_write_iter+0x18/0x20 [vhost_vdpa]\n      [<00000000de1cd4a0>] vfs_write+0x216/0x4b0\n      [<00000000a2850200>] ksys_write+0x71/0xf0\n      [<00000000de8e720b>] __x64_sys_write+0x19/0x20\n      [<0000000018b12cbb>] do_syscall_64+0x3f/0x90\n      [<00000000986ec465>] entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nLet's fix this calling vhost_vdpa_iotlb_unmap() on the whole range in\nvhost_vdpa_remove_as(). We move that call before vhost_dev_cleanup()\nsince we need a valid v->vdev.mm in vhost_vdpa_pa_unmap().\nvhost_iotlb_reset() call can be removed, since vhost_vdpa_iotlb_unmap()\non the whole range removes all the entries.\n\nThe kmemleak log reported was observed with a vDPA device that has `use_va`\nset to true (e.g. VDUSE). This patch has been tested with both types of\ndevices.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/4e92cb33bfb51eee5f28bb10846c46f266a4bb67","https://git.kernel.org/stable/c/a2907867e2c86067accd2f011d6f23ee5533aa6c","https://git.kernel.org/stable/c/c070c1912a83432530cbb4271d5b9b11fa36b67a"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:17:07.138532058+00:00"},"epss":{"cve":"CVE-2022-50738","score":0.00235,"percentile":0.14528,"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."]}