{"id":"CVE-2022-49871","url":"https://www.cyber-defence.io/tools/cve/CVE-2022-49871","generatedAt":"2026-10-27T17:39:11.228Z","title":"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…","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().","published":"2025-05-01T15:16:12.000Z","lastModified":"2026-06-17T05:19:22.000Z","status":"Modified","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-401"],"affected":["linux/linux kernel"],"epss":{"score":0.00217,"percentile":0.12091,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.22%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/1118b2049d77ca0b505775fc1a8d1909cf19a7ec","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/223ef6a94e52331a6a7ef31e59921e0e82d2d40a","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/3401f964028ac941425b9b2c8ff8a022539ef44a","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/8b12a020b20a78f62bedc50f26db3bf4fadf8cb9","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a4f73f6adc53fd7a3f9771cbc89a03ef39b0b755","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/d7569302a7a52a9305d2fb054df908ff985553bb","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2022-49871","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}