{"id":"CVE-2022-50738","summary":"vhost-vdpa: fix an iotlb memory leak","details":"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      [\u003c0000000087736d2a\u003e] kmem_cache_alloc_trace+0x142/0x1c0\n      [\u003c0000000060740f50\u003e] vhost_vdpa_process_iotlb_msg+0x68c/0x901 [vhost_vdpa]\n      [\u003c0000000083e8e205\u003e] vhost_chr_write_iter+0xc0/0x4a0 [vhost]\n      [\u003c000000008f2f414a\u003e] vhost_vdpa_chr_write_iter+0x18/0x20 [vhost_vdpa]\n      [\u003c00000000de1cd4a0\u003e] vfs_write+0x216/0x4b0\n      [\u003c00000000a2850200\u003e] ksys_write+0x71/0xf0\n      [\u003c00000000de8e720b\u003e] __x64_sys_write+0x19/0x20\n      [\u003c0000000018b12cbb\u003e] do_syscall_64+0x3f/0x90\n      [\u003c00000000986ec465\u003e] 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-\u003evdev.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.","modified":"2026-05-18T05:56:23.228906686Z","published":"2025-12-24T13:05:36.801Z","related":["SUSE-SU-2026:0263-1","SUSE-SU-2026:0317-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/50xxx/CVE-2022-50738.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/4e92cb33bfb51eee5f28bb10846c46f266a4bb67"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a2907867e2c86067accd2f011d6f23ee5533aa6c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c070c1912a83432530cbb4271d5b9b11fa36b67a"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/50xxx/CVE-2022-50738.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2022-50738"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"3d5698793897a2b9c0060d899881d1a0591630d5"},{"fixed":"4e92cb33bfb51eee5f28bb10846c46f266a4bb67"},{"fixed":"a2907867e2c86067accd2f011d6f23ee5533aa6c"},{"fixed":"c070c1912a83432530cbb4271d5b9b11fa36b67a"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2022-50738.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.19.0"},{"fixed":"6.0.19"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.1.0"},{"fixed":"6.1.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2022-50738.json"}}],"schema_version":"1.7.5"}