GHSA-J9XF-8J9Q-6CVR
Vulnerability from github – Published: 2025-06-18 12:30 – Updated: 2026-06-01 18:31In the Linux kernel, the following vulnerability has been resolved:
net: tap: NULL pointer derefence in dev_parse_header_protocol when skb->dev is null
Fixes a NULL pointer derefence bug triggered from tap driver. When tap_get_user calls virtio_net_hdr_to_skb the skb->dev is null (in tap.c skb->dev is set after the call to virtio_net_hdr_to_skb) virtio_net_hdr_to_skb calls dev_parse_header_protocol which needs skb->dev field to be valid.
The line that trigers the bug is in dev_parse_header_protocol (dev is at offset 0x10 from skb and is stored in RAX register) if (!dev->header_ops || !dev->header_ops->parse_protocol) 22e1: mov 0x10(%rbx),%rax 22e5: mov 0x230(%rax),%rax
Setting skb->dev before the call in tap.c fixes the issue.
BUG: kernel NULL pointer dereference, address: 0000000000000230 RIP: 0010:virtio_net_hdr_to_skb.constprop.0+0x335/0x410 [tap] Code: c0 0f 85 b7 fd ff ff eb d4 41 39 c6 77 cf 29 c6 48 89 df 44 01 f6 e8 7a 79 83 c1 48 85 c0 0f 85 d9 fd ff ff eb b7 48 8b 43 10 <48> 8b 80 30 02 00 00 48 85 c0 74 55 48 8b 40 28 48 85 c0 74 4c 48 RSP: 0018:ffffc90005c27c38 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888298f25300 RCX: 0000000000000010 RDX: 0000000000000005 RSI: ffffc90005c27cb6 RDI: ffff888298f25300 RBP: ffffc90005c27c80 R08: 00000000ffffffea R09: 00000000000007e8 R10: ffff88858ec77458 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000014 R14: ffffc90005c27e08 R15: ffffc90005c27cb6 FS: 0000000000000000(0000) GS:ffff88858ec40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000230 CR3: 0000000281408006 CR4: 00000000003706e0 Call Trace: tap_get_user+0x3f1/0x540 [tap] tap_sendmsg+0x56/0x362 [tap] ? get_tx_bufs+0xc2/0x1e0 [vhost_net] handle_tx_copy+0x114/0x670 [vhost_net] handle_tx+0xb0/0xe0 [vhost_net] handle_tx_kick+0x15/0x20 [vhost_net] vhost_worker+0x7b/0xc0 [vhost] ? vhost_vring_call_reset+0x40/0x40 [vhost] kthread+0xfa/0x120 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x1f/0x30
{
"affected": [],
"aliases": [
"CVE-2022-50073"
],
"database_specific": {
"cwe_ids": [
"CWE-476"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-06-18T11:15:36Z",
"severity": "MODERATE"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tap: NULL pointer derefence in dev_parse_header_protocol when skb-\u003edev is null\n\nFixes a NULL pointer derefence bug triggered from tap driver.\nWhen tap_get_user calls virtio_net_hdr_to_skb the skb-\u003edev is null\n(in tap.c skb-\u003edev is set after the call to virtio_net_hdr_to_skb)\nvirtio_net_hdr_to_skb calls dev_parse_header_protocol which\nneeds skb-\u003edev field to be valid.\n\nThe line that trigers the bug is in dev_parse_header_protocol\n(dev is at offset 0x10 from skb and is stored in RAX register)\n if (!dev-\u003eheader_ops || !dev-\u003eheader_ops-\u003eparse_protocol)\n 22e1: mov 0x10(%rbx),%rax\n 22e5:\t mov 0x230(%rax),%rax\n\nSetting skb-\u003edev before the call in tap.c fixes the issue.\n\nBUG: kernel NULL pointer dereference, address: 0000000000000230\nRIP: 0010:virtio_net_hdr_to_skb.constprop.0+0x335/0x410 [tap]\nCode: c0 0f 85 b7 fd ff ff eb d4 41 39 c6 77 cf 29 c6 48 89 df 44 01 f6 e8 7a 79 83 c1 48 85 c0 0f 85 d9 fd ff ff eb b7 48 8b 43 10 \u003c48\u003e 8b 80 30 02 00 00 48 85 c0 74 55 48 8b 40 28 48 85 c0 74 4c 48\nRSP: 0018:ffffc90005c27c38 EFLAGS: 00010246\nRAX: 0000000000000000 RBX: ffff888298f25300 RCX: 0000000000000010\nRDX: 0000000000000005 RSI: ffffc90005c27cb6 RDI: ffff888298f25300\nRBP: ffffc90005c27c80 R08: 00000000ffffffea R09: 00000000000007e8\nR10: ffff88858ec77458 R11: 0000000000000000 R12: 0000000000000001\nR13: 0000000000000014 R14: ffffc90005c27e08 R15: ffffc90005c27cb6\nFS: 0000000000000000(0000) GS:ffff88858ec40000(0000) knlGS:0000000000000000\nCS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 0000000000000230 CR3: 0000000281408006 CR4: 00000000003706e0\nCall Trace:\n tap_get_user+0x3f1/0x540 [tap]\n tap_sendmsg+0x56/0x362 [tap]\n ? get_tx_bufs+0xc2/0x1e0 [vhost_net]\n handle_tx_copy+0x114/0x670 [vhost_net]\n handle_tx+0xb0/0xe0 [vhost_net]\n handle_tx_kick+0x15/0x20 [vhost_net]\n vhost_worker+0x7b/0xc0 [vhost]\n ? vhost_vring_call_reset+0x40/0x40 [vhost]\n kthread+0xfa/0x120\n ? kthread_complete_and_exit+0x20/0x20\n ret_from_fork+0x1f/0x30",
"id": "GHSA-j9xf-8j9q-6cvr",
"modified": "2026-06-01T18:31:20Z",
"published": "2025-06-18T12:30:46Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-50073"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/447ba770cfe798925f4923548b367fd49f0ee5f0"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/4f61f133f354853bc394ec7d6028adb9b02dd701"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/8f90163f9e013c8fc791aab338aab44a46044cfc"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/dd29648fcf69339713f2d25f7014ae905dcdfc18"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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