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  4. CVE 2021 47400 net hns3 do not allow call hns3nicnetopen
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Back to active CVEs
High · CVSS 7.8CVE-2021-47400

net: hns3: do not allow call hns3_nic_net_open repeatedlyCVE-2021-47400

Answer in brief

CVE-2021-47400 records a High severity (CVSS 7.8) vulnerability in net: hns3: do not allow call hns3_nic_net_open repeatedly. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published May 21, 2024Updated Aug 5, 2026Source checked Nov 5, 2026First seen by HOL Aug 4, 2026Material review Aug 5, 2026
Upstream Advisory

Key facts

Risk
High · CVSS 7.8
Exploitation
Not marked as known exploited
Affected software
6 mapped packages or products
Fix availability
Available

Why this deserves its current priority

CVSS is 7.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Affected products and reported versions
ProductAffected versionsFixed versions
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:*Not reportedNot reported
cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:*Not reportedNot reported
Mapped affected packages and fixed versions
PackageAffected rangeFixed version
Linux/Linuxgeneric>=e888402789b9db5de4fcda361331d66dbf0cd9fd <5a31d4e73ada8022427b69b10fd1f01a6a8d4b3d || >=e888402789b9db5de4fcda361331d66dbf0cd9fd <f8ba689cb69523144d10606096ef686002dd7285 || >=e888402789b9db5de4fcda361331d66dbf0cd9fd <3dac38bdce7932901b9f0b71c62331852c809e61 || >=e888402789b9db5de4fcda361331d66dbf0cd9fd <5b09e88e1bf7fe86540fab4b5f3eece8abead39e5a31d4e73ada8022427b69b10fd1f01a6a8d4b3d, f8ba689cb69523144d10606096ef686002dd7285, 3dac38bdce7932901b9f0b71c62331852c809e61, 5b09e88e1bf7fe86540fab4b5f3eece8abead39e
Linux/Linuxgeneric5.0Not reported

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
  2. 2Review the reported fix. Update Linux/Linux to 5a31d4e73ada8022427b69b10fd1f01a6a8d4b3d if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    May 21, 2024

    Evidence: source:cvelist:source_dates:source-dates:record
  2. Source modified

    Aug 5, 2026

    Evidence: source:cvelist:source_dates:source-dates:record
  3. First seen by HOL

    Aug 4, 2026

Sources and claim methodology

  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
  • Source referencegit.kernel.org
Upstream source description

In the Linux kernel, the following vulnerability has been resolved: net: hns3: do not allow call hns3_nic_net_open repeatedly hns3_nic_net_open() is not allowed to called repeatly, but there is no checking for this. When doing device reset and setup tc concurrently, there is a small oppotunity to call hns3_nic_net_open repeatedly, and cause kernel bug by calling napi_enable twice. The calltrace information is like below: [ 3078.222780] ------------[ cut here ]------------ [ 3078.230255] kernel BUG at net/core/dev.c:6991! [ 3078.236224] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP [ 3078.243431] Modules linked in: hns3 hclgevf hclge hnae3 vfio_iommu_type1 vfio_pci vfio_virqfd vfio pv680_mii(O) [ 3078.258880] CPU: 0 PID: 295 Comm: kworker/u8:5 Tainted: G O 5.14.0-rc4+ #1 [ 3078.269102] Hardware name: , BIOS KpxxxFPGA 1P B600 V181 08/12/2021 [ 3078.276801] Workqueue: hclge hclge_service_task [hclge] [ 3078.288774] pstate: 60400009 (nZCv daif +PAN -UAO -TCO BTYPE=--) [ 3078.296168] pc : napi_enable+0x80/0x84 tc qdisc sho[w 3d0e7v8 .e3t0h218 79] lr : hns3_nic_net_open+0x138/0x510 [hns3] [ 3078.314771] sp : ffff8000108abb20 [ 3078.319099] x29: ffff8000108abb20 x28: 0000000000000000 x27: ffff0820a8490300 [ 3078.329121] x26: 0000000000000001 x25: ffff08209cfc6200 x24: 0000000000000000 [ 3078.339044] x23: ffff0820a8490300 x22: ffff08209cd76000 x21: ffff0820abfe3880 [ 3078.349018] x20: 0000000000000000 x19: ffff08209cd76900 x18: 0000000000000000 [ 3078.358620] x17: 0000000000000000 x16: ffffc816e1727a50 x15: 0000ffff8f4ff930 [ 3078.368895] x14: 0000000000000000 x13: 0000000000000000 x12: 0000259e9dbeb6b4 [ 3078.377987] x11: 0096a8f7e764eb40 x10: 634615ad28d3eab5 x9 : ffffc816ad8885b8 [ 3078.387091] x8 : ffff08209cfc6fb8 x7 : ffff0820ac0da058 x6 : ffff0820a8490344 [ 3078.396356] x5 : 0000000000000140 x4 : 0000000000000003 x3 : ffff08209cd76938 [ 3078.405365] x2 : 0000000000000000 x1 : 0000000000000010 x0 : ffff0820abfe38a0 [ 3078.414657] Call trace: [ 3078.418517] napi_enable+0x80/0x84 [ 3078.424626] hns3_reset_notify_up_enet+0x78/0xd0 [hns3] [ 3078.433469] hns3_reset_notify+0x64/0x80 [hns3] [ 3078.441430] hclge_notify_client+0x68/0xb0 [hclge] [ 3078.450511] hclge_reset_rebuild+0x524/0x884 [hclge] [ 3078.458879] hclge_reset_service_task+0x3c4/0x680 [hclge] [ 3078.467470] hclge_service_task+0xb0/0xb54 [hclge] [ 3078.475675] process_one_work+0x1dc/0x48c [ 3078.481888] worker_thread+0x15c/0x464 [ 3078.487104] kthread+0x160/0x170 [ 3078.492479] ret_from_fork+0x10/0x18 [ 3078.498785] Code: c8027c81 35ffffa2 d50323bf d65f03c0 (d4210000) [ 3078.506889] ---[ end trace 8ebe0340a1b0fb44 ]--- Once hns3_nic_net_open() is excute success, the flag HNS3_NIC_STATE_DOWN will be cleared. So add checking for this flag, directly return when HNS3_NIC_STATE_DOWN is no set.

Quoted source text, attributed separately from HOL analysis.

Record context

Vulnerability class
Vulnerability
EPSS
Not reported
CWE IDs
NVD-CWE-noinfo
Source
CVE List V5
Source checked
Nov 5, 2026
References
4 linked sources
Open source record