{"cve":"CVE-2022-49871","nvd":{"published":"2025-05-01T15:16:12.030","modified":"2026-06-17T05:19:22.317","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tun: Fix memory leaks of napi_get_frags\n\nkmemleak reports after running test_progs:\n\nunreferenced object 0xffff8881b1672dc0 (size 232):\n  comm \"test_progs\", pid 394388, jiffies 4354712116 (age 841.975s)\n  hex dump (first 32 bytes):\n    e0 84 d7 a8 81 88 ff ff 80 2c 67 b1 81 88 ff ff  .........,g.....\n    00 40 c5 9b 81 88 ff ff 00 00 00 00 00 00 00 00  .@..............\n  backtrace:\n    [<00000000c8f01748>] napi_skb_cache_get+0xd4/0x150\n    [<0000000041c7fc09>] __napi_build_skb+0x15/0x50\n    [<00000000431c7079>] __napi_alloc_skb+0x26e/0x540\n    [<000000003ecfa30e>] napi_get_frags+0x59/0x140\n    [<0000000099b2199e>] tun_get_user+0x183d/0x3bb0 [tun]\n    [<000000008a5adef0>] tun_chr_write_iter+0xc0/0x1b1 [tun]\n    [<0000000049993ff4>] do_iter_readv_writev+0x19f/0x320\n    [<000000008f338ea2>] do_iter_write+0x135/0x630\n    [<000000008a3377a4>] vfs_writev+0x12e/0x440\n    [<00000000a6b5639a>] do_writev+0x104/0x280\n    [<00000000ccf065d8>] do_syscall_64+0x3b/0x90\n    [<00000000d776e329>] entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nThe issue occurs in the following scenarios:\ntun_get_user()\n  napi_gro_frags()\n    napi_frags_finish()\n      case GRO_NORMAL:\n        gro_normal_one()\n          list_add_tail(&skb->list, &napi->rx_list);\n          <-- While napi->rx_count < READ_ONCE(gro_normal_batch),\n          <-- gro_normal_list() is not called, napi->rx_list is not empty\n  <-- not ask to complete the gro work, will cause memory leaks in\n  <-- following tun_napi_del()\n...\ntun_napi_del()\n  netif_napi_del()\n    __netif_napi_del()\n    <-- &napi->rx_list is not empty, which caused memory leaks\n\nTo fix, add napi_complete() after napi_gro_frags().","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-401"],"references":["https://git.kernel.org/stable/c/1118b2049d77ca0b505775fc1a8d1909cf19a7ec","https://git.kernel.org/stable/c/223ef6a94e52331a6a7ef31e59921e0e82d2d40a","https://git.kernel.org/stable/c/3401f964028ac941425b9b2c8ff8a022539ef44a","https://git.kernel.org/stable/c/8b12a020b20a78f62bedc50f26db3bf4fadf8cb9","https://git.kernel.org/stable/c/a4f73f6adc53fd7a3f9771cbc89a03ef39b0b755"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:01:22.920403922+00:00"},"epss":{"cve":"CVE-2022-49871","score":0.00217,"percentile":0.12238,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}