{"affected":[],"cveId":"CVE-2022-50738","cwes":[],"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.","epss":null,"exploits":[],"kev":null,"metrics":[],"modifiedAt":1794312600177,"publishedAt":1766582160503,"references":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"url":"https://git.kernel.org/stable/c/4e92cb33bfb51eee5f28bb10846c46f266a4bb67"},{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"url":"https://git.kernel.org/stable/c/a2907867e2c86067accd2f011d6f23ee5533aa6c"},{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"url":"https://git.kernel.org/stable/c/c070c1912a83432530cbb4271d5b9b11fa36b67a"}],"remediation":[],"revision":"774500478003aed15611112976acb1274773fc729c5e6910019c1f5707443e9f","sources":[{"modifiedAt":1794312600177,"name":"NVD","retrievedAt":1794313075620,"url":"https://nvd.nist.gov/vuln/detail/CVE-2022-50738"}],"ssvc":null,"status":"published","title":"CVE-2022-50738","updatedAt":1794313075620}