{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2021-47517","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-05-24T15:02:54.824Z","datePublished":"2024-05-24T15:09:30.675Z","dateUpdated":"2025-05-04T07:12:41.633Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2025-05-04T07:12:41.633Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nethtool: do not perform operations on net devices being unregistered\n\nThere is a short period between a net device starts to be unregistered\nand when it is actually gone. In that time frame ethtool operations\ncould still be performed, which might end up in unwanted or undefined\nbehaviours[1].\n\nDo not allow ethtool operations after a net device starts its\nunregistration. This patch targets the netlink part as the ioctl one\nisn't affected: the reference to the net device is taken and the\noperation is executed within an rtnl lock section and the net device\nwon't be found after unregister.\n\n[1] For example adding Tx queues after unregister ends up in NULL\n    pointer exceptions and UaFs, such as:\n\n      BUG: KASAN: use-after-free in kobject_get+0x14/0x90\n      Read of size 1 at addr ffff88801961248c by task ethtool/755\n\n      CPU: 0 PID: 755 Comm: ethtool Not tainted 5.15.0-rc6+ #778\n      Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-4.fc34 04/014\n      Call Trace:\n       dump_stack_lvl+0x57/0x72\n       print_address_description.constprop.0+0x1f/0x140\n       kasan_report.cold+0x7f/0x11b\n       kobject_get+0x14/0x90\n       kobject_add_internal+0x3d1/0x450\n       kobject_init_and_add+0xba/0xf0\n       netdev_queue_update_kobjects+0xcf/0x200\n       netif_set_real_num_tx_queues+0xb4/0x310\n       veth_set_channels+0x1c3/0x550\n       ethnl_set_channels+0x524/0x610"}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ethtool/netlink.c"],"versions":[{"version":"041b1c5d4a53e97fc9e029ae32469552ca12cb9b","lessThan":"7c26da3be1e9843a15b5318f90db8a564479d2ac","status":"affected","versionType":"git"},{"version":"041b1c5d4a53e97fc9e029ae32469552ca12cb9b","lessThan":"cfd719f04267108f5f5bf802b9d7de69e99a99f9","status":"affected","versionType":"git"},{"version":"041b1c5d4a53e97fc9e029ae32469552ca12cb9b","lessThan":"dde91ccfa25fd58f64c397d91b81a4b393100ffa","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ethtool/netlink.c"],"versions":[{"version":"5.6","status":"affected"},{"version":"0","lessThan":"5.6","status":"unaffected","versionType":"semver"},{"version":"5.10.87","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.8","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"5.16","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.6","versionEndExcluding":"5.10.87"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.6","versionEndExcluding":"5.15.8"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.6","versionEndExcluding":"5.16"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/7c26da3be1e9843a15b5318f90db8a564479d2ac"},{"url":"https://git.kernel.org/stable/c/cfd719f04267108f5f5bf802b9d7de69e99a99f9"},{"url":"https://git.kernel.org/stable/c/dde91ccfa25fd58f64c397d91b81a4b393100ffa"}],"title":"ethtool: do not perform operations on net devices being unregistered","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2021-47517","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2024-05-24T19:18:28.551288Z"}}}],"providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2024-06-04T17:13:57.373Z"}},{"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2024-08-04T05:39:59.610Z"},"title":"CVE Program Container","references":[{"url":"https://git.kernel.org/stable/c/7c26da3be1e9843a15b5318f90db8a564479d2ac","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/cfd719f04267108f5f5bf802b9d7de69e99a99f9","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/dde91ccfa25fd58f64c397d91b81a4b393100ffa","tags":["x_transferred"]}]}]}}