CVE-2022-49871
net: tun: Fix memory leaks of napi_get_frags
- Published
- Updated
- Reserved
- Assigned by
- Linux
Description
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().
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.22% · top 88% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.
Weakness
Affected products
- affected 90e33d45940793def6f773b2d528e9f3c84ffdc7 – < 223ef6a94e52331a6a7ef31e59921e0e82d2d40a
- affected 90e33d45940793def6f773b2d528e9f3c84ffdc7 – < a4f73f6adc53fd7a3f9771cbc89a03ef39b0b755
- affected 90e33d45940793def6f773b2d528e9f3c84ffdc7 – < 3401f964028ac941425b9b2c8ff8a022539ef44a
- affected 90e33d45940793def6f773b2d528e9f3c84ffdc7 – < d7569302a7a52a9305d2fb054df908ff985553bb
- affected 90e33d45940793def6f773b2d528e9f3c84ffdc7 – < 8b12a020b20a78f62bedc50f26db3bf4fadf8cb9
- affected 90e33d45940793def6f773b2d528e9f3c84ffdc7 – < 1118b2049d77ca0b505775fc1a8d1909cf19a7ec
- affected 4.15
- unaffected < 4.15
- unaffected 4.19.267 – ≤ 4.19.*
- unaffected 5.4.225 – ≤ 5.4.*
- unaffected 5.10.155 – ≤ 5.10.*
- unaffected 5.15.79 – ≤ 5.15.*
- unaffected 6.0.9 – ≤ 6.0.*
- unaffected 6.1 – ≤ *
References (6)
- https://git.kernel.org/stable/c/223ef6a94e52331a6a7ef31e59921e0e82d2d40a (opens in a new tab)
- https://git.kernel.org/stable/c/a4f73f6adc53fd7a3f9771cbc89a03ef39b0b755 (opens in a new tab)
- https://git.kernel.org/stable/c/3401f964028ac941425b9b2c8ff8a022539ef44a (opens in a new tab)
- https://git.kernel.org/stable/c/d7569302a7a52a9305d2fb054df908ff985553bb (opens in a new tab)
- https://git.kernel.org/stable/c/8b12a020b20a78f62bedc50f26db3bf4fadf8cb9 (opens in a new tab)
- https://git.kernel.org/stable/c/1118b2049d77ca0b505775fc1a8d1909cf19a7ec (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2022-49871)Record last updated .