CVE-2021-47554 vdpa_sim: avoid putting an uninitialized iova_domain

2024-05-2415:09:56

Linux

www.cve.org

linux kernel

vdpa_sim

vulnerability

resolved

iova_domain

crash

6.3 Medium

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

9.0%

JSON

In the Linux kernel, the following vulnerability has been resolved:

vdpa_sim: avoid putting an uninitialized iova_domain

The system will crash if we put an uninitialized iova_domain, this
could happen when an error occurs before initializing the iova_domain
in vdpasim_create().

BUG: kernel NULL pointer dereference, address: 0000000000000000
…
RIP: 0010:__cpuhp_state_remove_instance+0x96/0x1c0
…
Call Trace:
<TASK>
put_iova_domain+0x29/0x220
vdpasim_free+0xd1/0x120 [vdpa_sim]
vdpa_release_dev+0x21/0x40 [vdpa]
device_release+0x33/0x90
kobject_release+0x63/0x160
vdpasim_create+0x127/0x2a0 [vdpa_sim]
vdpasim_net_dev_add+0x7d/0xfe [vdpa_sim_net]
vdpa_nl_cmd_dev_add_set_doit+0xe1/0x1a0 [vdpa]
genl_family_rcv_msg_doit+0x112/0x140
genl_rcv_msg+0xdf/0x1d0
…

So we must make sure the iova_domain is already initialized before
put it.

In addition, we may get the following warning in this case:
WARNING: … drivers/iommu/iova.c:344 iova_cache_put+0x58/0x70

So we must make sure the iova_cache_put() is invoked only if the
iova_cache_get() is already invoked. Let’s fix it together.

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/vdpa/vdpa_sim/vdpa_sim.c"
    ],
    "versions": [
      {
        "version": "4080fc106750",
        "lessThan": "e4d58ac67e63",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "4080fc106750",
        "lessThan": "bb93ce4b150d",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "drivers/vdpa/vdpa_sim/vdpa_sim.c"
    ],
    "versions": [
      {
        "version": "5.13",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "5.13",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.15.6",
        "lessThanOrEqual": "5.15.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.16",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]