{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2021-47222","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-04-10T18:59:19.529Z","datePublished":"2024-05-21T14:19:28.214Z","dateUpdated":"2025-05-04T07:06:37.233Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2025-05-04T07:06:37.233Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bridge: fix vlan tunnel dst refcnt when egressing\n\nThe egress tunnel code uses dst_clone() and directly sets the result\nwhich is wrong because the entry might have 0 refcnt or be already deleted,\ncausing number of problems. It also triggers the WARN_ON() in dst_hold()[1]\nwhen a refcnt couldn't be taken. Fix it by using dst_hold_safe() and\nchecking if a reference was actually taken before setting the dst.\n\n[1] dmesg WARN_ON log and following refcnt errors\n WARNING: CPU: 5 PID: 38 at include/net/dst.h:230 br_handle_egress_vlan_tunnel+0x10b/0x134 [bridge]\n Modules linked in: 8021q garp mrp bridge stp llc bonding ipv6 virtio_net\n CPU: 5 PID: 38 Comm: ksoftirqd/5 Kdump: loaded Tainted: G        W         5.13.0-rc3+ #360\n Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014\n RIP: 0010:br_handle_egress_vlan_tunnel+0x10b/0x134 [bridge]\n Code: e8 85 bc 01 e1 45 84 f6 74 90 45 31 f6 85 db 48 c7 c7 a0 02 19 a0 41 0f 94 c6 31 c9 31 d2 44 89 f6 e8 64 bc 01 e1 85 db 75 02 <0f> 0b 31 c9 31 d2 44 89 f6 48 c7 c7 70 02 19 a0 e8 4b bc 01 e1 49\n RSP: 0018:ffff8881003d39e8 EFLAGS: 00010246\n RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000\n RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffffa01902a0\n RBP: ffff8881040c6700 R08: 0000000000000000 R09: 0000000000000001\n R10: 2ce93d0054fe0d00 R11: 54fe0d00000e0000 R12: ffff888109515000\n R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000401\n FS:  0000000000000000(0000) GS:ffff88822bf40000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 00007f42ba70f030 CR3: 0000000109926000 CR4: 00000000000006e0\n Call Trace:\n  br_handle_vlan+0xbc/0xca [bridge]\n  __br_forward+0x23/0x164 [bridge]\n  deliver_clone+0x41/0x48 [bridge]\n  br_handle_frame_finish+0x36f/0x3aa [bridge]\n  ? skb_dst+0x2e/0x38 [bridge]\n  ? br_handle_ingress_vlan_tunnel+0x3e/0x1c8 [bridge]\n  ? br_handle_frame_finish+0x3aa/0x3aa [bridge]\n  br_handle_frame+0x2c3/0x377 [bridge]\n  ? __skb_pull+0x33/0x51\n  ? vlan_do_receive+0x4f/0x36a\n  ? br_handle_frame_finish+0x3aa/0x3aa [bridge]\n  __netif_receive_skb_core+0x539/0x7c6\n  ? __list_del_entry_valid+0x16e/0x1c2\n  __netif_receive_skb_list_core+0x6d/0xd6\n  netif_receive_skb_list_internal+0x1d9/0x1fa\n  gro_normal_list+0x22/0x3e\n  dev_gro_receive+0x55b/0x600\n  ? detach_buf_split+0x58/0x140\n  napi_gro_receive+0x94/0x12e\n  virtnet_poll+0x15d/0x315 [virtio_net]\n  __napi_poll+0x2c/0x1c9\n  net_rx_action+0xe6/0x1fb\n  __do_softirq+0x115/0x2d8\n  run_ksoftirqd+0x18/0x20\n  smpboot_thread_fn+0x183/0x19c\n  ? smpboot_unregister_percpu_thread+0x66/0x66\n  kthread+0x10a/0x10f\n  ? kthread_mod_delayed_work+0xb6/0xb6\n  ret_from_fork+0x22/0x30\n ---[ end trace 49f61b07f775fd2b ]---\n dst_release: dst:00000000c02d677a refcnt:-1\n dst_release underflow"}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/bridge/br_vlan_tunnel.c"],"versions":[{"version":"11538d039ac6efcf4f1a6c536e1b87cd3668a9fd","lessThan":"42020f7f37a90d24b9551f5f7eba3f7c7c102968","status":"affected","versionType":"git"},{"version":"11538d039ac6efcf4f1a6c536e1b87cd3668a9fd","lessThan":"84fc1c944e45ab317e2e70a0e7f76fa2a5e43b6e","status":"affected","versionType":"git"},{"version":"11538d039ac6efcf4f1a6c536e1b87cd3668a9fd","lessThan":"79855be6445b6592bddb7bd7167083ec8cdbd73f","status":"affected","versionType":"git"},{"version":"11538d039ac6efcf4f1a6c536e1b87cd3668a9fd","lessThan":"fc7fdd8c5c2ad2fe3e297698be9d4dbe4a4e0579","status":"affected","versionType":"git"},{"version":"11538d039ac6efcf4f1a6c536e1b87cd3668a9fd","lessThan":"25053a8404ba17ca48f5553d487afc1882e9f56c","status":"affected","versionType":"git"},{"version":"11538d039ac6efcf4f1a6c536e1b87cd3668a9fd","lessThan":"cfc579f9d89af4ada58c69b03bcaa4887840f3b3","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/bridge/br_vlan_tunnel.c"],"versions":[{"version":"4.11","status":"affected"},{"version":"0","lessThan":"4.11","status":"unaffected","versionType":"semver"},{"version":"4.14.238","lessThanOrEqual":"4.14.*","status":"unaffected","versionType":"semver"},{"version":"4.19.196","lessThanOrEqual":"4.19.*","status":"unaffected","versionType":"semver"},{"version":"5.4.128","lessThanOrEqual":"5.4.*","status":"unaffected","versionType":"semver"},{"version":"5.10.46","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.12.13","lessThanOrEqual":"5.12.*","status":"unaffected","versionType":"semver"},{"version":"5.13","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":"4.11","versionEndExcluding":"4.14.238"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.11","versionEndExcluding":"4.19.196"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.11","versionEndExcluding":"5.4.128"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.11","versionEndExcluding":"5.10.46"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.11","versionEndExcluding":"5.12.13"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.11","versionEndExcluding":"5.13"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/42020f7f37a90d24b9551f5f7eba3f7c7c102968"},{"url":"https://git.kernel.org/stable/c/84fc1c944e45ab317e2e70a0e7f76fa2a5e43b6e"},{"url":"https://git.kernel.org/stable/c/79855be6445b6592bddb7bd7167083ec8cdbd73f"},{"url":"https://git.kernel.org/stable/c/fc7fdd8c5c2ad2fe3e297698be9d4dbe4a4e0579"},{"url":"https://git.kernel.org/stable/c/25053a8404ba17ca48f5553d487afc1882e9f56c"},{"url":"https://git.kernel.org/stable/c/cfc579f9d89af4ada58c69b03bcaa4887840f3b3"}],"title":"net: bridge: fix vlan tunnel dst refcnt when egressing","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2024-08-04T05:32:07.465Z"},"title":"CVE Program Container","references":[{"url":"https://git.kernel.org/stable/c/42020f7f37a90d24b9551f5f7eba3f7c7c102968","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/84fc1c944e45ab317e2e70a0e7f76fa2a5e43b6e","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/79855be6445b6592bddb7bd7167083ec8cdbd73f","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/fc7fdd8c5c2ad2fe3e297698be9d4dbe4a4e0579","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/25053a8404ba17ca48f5553d487afc1882e9f56c","tags":["x_transferred"]},{"url":"https://git.kernel.org/stable/c/cfc579f9d89af4ada58c69b03bcaa4887840f3b3","tags":["x_transferred"]}]},{"metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2021-47222","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2024-09-10T15:40:13.415831Z"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2024-09-11T17:32:48.159Z"}}]}}