{"id":"CVE-2022-49871","state":"PUBLISHED","title":"net: tun: Fix memory leaks of napi_get_frags","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().","publishedAt":"2025-05-01T14:10:21.760Z","updatedAt":"2026-05-11T19:08:21.371Z","severity":{"score":5.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"90e33d45940793def6f773b2d528e9f3c84ffdc7","status":"affected","lessThan":"223ef6a94e52331a6a7ef31e59921e0e82d2d40a","versionType":"git"},{"version":"90e33d45940793def6f773b2d528e9f3c84ffdc7","status":"affected","lessThan":"a4f73f6adc53fd7a3f9771cbc89a03ef39b0b755","versionType":"git"},{"version":"90e33d45940793def6f773b2d528e9f3c84ffdc7","status":"affected","lessThan":"3401f964028ac941425b9b2c8ff8a022539ef44a","versionType":"git"},{"version":"90e33d45940793def6f773b2d528e9f3c84ffdc7","status":"affected","lessThan":"d7569302a7a52a9305d2fb054df908ff985553bb","versionType":"git"},{"version":"90e33d45940793def6f773b2d528e9f3c84ffdc7","status":"affected","lessThan":"8b12a020b20a78f62bedc50f26db3bf4fadf8cb9","versionType":"git"},{"version":"90e33d45940793def6f773b2d528e9f3c84ffdc7","status":"affected","lessThan":"1118b2049d77ca0b505775fc1a8d1909cf19a7ec","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/tun.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.15","versionType":"semver"},{"version":"4.19.267","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.225","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.155","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.79","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.0.9","status":"unaffected","lessThanOrEqual":"6.0.*","versionType":"semver"},{"version":"6.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/tun.c"]}],"references":["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"],"weaknesses":["CWE-401"],"ingestedAt":"2026-10-29T20:05:26.763Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2022/49xxx/CVE-2022-49871.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2022-49871","state":"PUBLISHED","datePublished":"2025-05-01T14:10:21.760Z","dateUpdated":"2026-05-11T19:08:21.371Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-05-01T14:05:17.238Z"},"containers":{"cna":{"title":"net: tun: Fix memory leaks of napi_get_frags","descriptions":[{"lang":"en","value":"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()."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"90e33d45940793def6f773b2d528e9f3c84ffdc7","status":"affected","lessThan":"223ef6a94e52331a6a7ef31e59921e0e82d2d40a","versionType":"git"},{"version":"90e33d45940793def6f773b2d528e9f3c84ffdc7","status":"affected","lessThan":"a4f73f6adc53fd7a3f9771cbc89a03ef39b0b755","versionType":"git"},{"version":"90e33d45940793def6f773b2d528e9f3c84ffdc7","status":"affected","lessThan":"3401f964028ac941425b9b2c8ff8a022539ef44a","versionType":"git"},{"version":"90e33d45940793def6f773b2d528e9f3c84ffdc7","status":"affected","lessThan":"d7569302a7a52a9305d2fb054df908ff985553bb","versionType":"git"},{"version":"90e33d45940793def6f773b2d528e9f3c84ffdc7","status":"affected","lessThan":"8b12a020b20a78f62bedc50f26db3bf4fadf8cb9","versionType":"git"},{"version":"90e33d45940793def6f773b2d528e9f3c84ffdc7","status":"affected","lessThan":"1118b2049d77ca0b505775fc1a8d1909cf19a7ec","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/tun.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.15","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.15","versionType":"semver"},{"version":"4.19.267","status":"unaffected","lessThanOrEqual":"4.19.*","versionType":"semver"},{"version":"5.4.225","status":"unaffected","lessThanOrEqual":"5.4.*","versionType":"semver"},{"version":"5.10.155","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.79","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.0.9","status":"unaffected","lessThanOrEqual":"6.0.*","versionType":"semver"},{"version":"6.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/tun.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/223ef6a94e52331a6a7ef31e59921e0e82d2d40a"},{"url":"https://git.kernel.org/stable/c/a4f73f6adc53fd7a3f9771cbc89a03ef39b0b755"},{"url":"https://git.kernel.org/stable/c/3401f964028ac941425b9b2c8ff8a022539ef44a"},{"url":"https://git.kernel.org/stable/c/d7569302a7a52a9305d2fb054df908ff985553bb"},{"url":"https://git.kernel.org/stable/c/8b12a020b20a78f62bedc50f26db3bf4fadf8cb9"},{"url":"https://git.kernel.org/stable/c/1118b2049d77ca0b505775fc1a8d1909cf19a7ec"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T19:08:21.371Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"4.19.267"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"5.4.225"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"5.10.155"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"5.15.79"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.0.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.1"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":5.5,"attackVector":"LOCAL","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"timestamp":"2025-10-01T16:03:55.727122Z","id":"CVE-2022-49871","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-401","type":"CWE","lang":"en","description":"CWE-401 Missing Release of Memory after Effective Lifetime"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-10-01T16:03:58.029Z"}}]}}}