net: tun: Fix memory leaks of napi_get_frags
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 4 without a fix
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-401.
Summary
In the Linux kernel, the following vulnerability has been resolved: net: tun: Fix memory leaks of napi_get_frags kmemleak reports after running test_progs: unreferenced object 0xffff8881b1672dc0 (size 232): comm "test_progs", pid 394388, jiffies 4354712116 (age 841.975s) hex dump (first 32 bytes): e0 84 d7 a8 81 88 ff ff 80 2c 67 b1 81 88 ff ff .........,g..... 00 40 c5 9b 81 88 ff ff 00 00 00 00 00 00 00 00 .@.............. backtrace: [<00000000c8f01748>] napi_skb_cache_get+0xd4/0x150 [<0000000041c7fc09>] __napi_build_skb+0x15/0x50 [<00000000431c7079>] __napi_alloc_skb+0x26e/0x540 [<000000003ecfa30e>] napi_get_frags+0x59/0x140 [<0000000099b2199e>] tun_get_user+0x183d/0x3bb0 [tun] [<000000008a5adef0>] tun_chr_write_iter+0xc0/0x1b1 [tun] [<0000000049993ff4>] do_iter_readv_writev+0x19f/0x320 [<000000008f338ea2>] do_iter_write+0x135/0x630 [<000000008a3377a4>] vfs_writev+0x12e/0x440 [<00000000a6b5639a>] do_writev+0x104/0x280 [<00000000ccf065d8>] do_syscall_64+0x3b/0x90 [<00000000d776e329>] entry_SYSCALL_64_after_hwframe+0x63/0xcd The issue occurs in the following scenarios: tun_get_user() napi_gro_frags() napi_frags_finish() case GRO_NORMAL: gro_normal_one() list_add_tail(&skb->list, &napi->rx_list); <-- While napi->rx_count < READ_ONCE(gro_normal_batch), <-- gro_normal_list() is not called, napi->rx_list is not empty <-- not ask to complete the gro work, will cause memory leaks in <-- following tun_napi_del() ... tun_napi_del() netif_napi_del() __netif_napi_del() <-- &napi->rx_list is not empty, which caused memory leaks To fix, add napi_complete() after napi_gro_frags().
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 4.15 and later | 4.19.267, 5.4.225, 5.10.155, 5.15.79, 6.0.9, 6.1 | Patch available | CNA |
- Linux VendorLinux Affected 4.15 and later Fixed in 4.19.267, 5.4.225, 5.10.155, 5.15.79, 6.0.9, 6.1 Patch available CNA
CPE configurations NVD · 5
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 4.15 to before 4.19.267; 4.20 to before 5.4.225; 5.5 to before 5.10.155; 5.11 to before 5.15.79; 5.16 to before 6.0.9 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.1:rc1:*:*:*:*:*:* | 6.1 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.1:rc2:*:*:*:*:*:* | 6.1 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.1:rc3:*:*:*:*:*:* | 6.1 rc3 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.1:rc4:*:*:*:*:*:* | 6.1 rc4 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 4.15 to before 4.19.267; 4.20 to before 5.4.225; 5.5 to before 5.10.155; 5.11 to before 5.15.79; 5.16 to before 6.0.9 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.1:rc1:*:*:*:*:*:* Versions 6.1 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.1:rc2:*:*:*:*:*:* Versions 6.1 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.1:rc3:*:*:*:*:*:* Versions 6.1 rc3 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.1:rc4:*:*:*:*:*:* Versions 6.1 rc4 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 4.19.267, 5.4.225, 5.10.155, 5.15.79, 6.0.9, 6.1
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 8 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
Not affected: 1 product
- Red Hat Enterprise Linux 10
Timeline
- 2026-10-02 Threatist record created from CVE-2022-49871
- 2026-10-03 Alias added: GHSA-jfw6-w783-5hhm
References
Patch 6
- https://git.kernel.org/stable/c/223ef6a94e52331a6a7ef31e59921e0e82d2d40a
- https://git.kernel.org/stable/c/a4f73f6adc53fd7a3f9771cbc89a03ef39b0b755
- https://git.kernel.org/stable/c/3401f964028ac941425b9b2c8ff8a022539ef44a
- https://git.kernel.org/stable/c/d7569302a7a52a9305d2fb054df908ff985553bb
- https://git.kernel.org/stable/c/8b12a020b20a78f62bedc50f26db3bf4fadf8cb9
- https://git.kernel.org/stable/c/1118b2049d77ca0b505775fc1a8d1909cf19a7ec
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- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2022-49871 · CVE Program
- CVE-2022-49871 · NVD
- FIRST EPSS
- GHSA-jfw6-w783-5hhm · GitHub Advisory Database · CC BY 4.0
- CVE-2022-49871 · Red Hat security data · CC BY 4.0
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