{"id":"CVE-2022-49871","summary":"net: tun: Fix memory leaks of napi_get_frags","details":"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    [\u003c00000000c8f01748\u003e] napi_skb_cache_get+0xd4/0x150\n    [\u003c0000000041c7fc09\u003e] __napi_build_skb+0x15/0x50\n    [\u003c00000000431c7079\u003e] __napi_alloc_skb+0x26e/0x540\n    [\u003c000000003ecfa30e\u003e] napi_get_frags+0x59/0x140\n    [\u003c0000000099b2199e\u003e] tun_get_user+0x183d/0x3bb0 [tun]\n    [\u003c000000008a5adef0\u003e] tun_chr_write_iter+0xc0/0x1b1 [tun]\n    [\u003c0000000049993ff4\u003e] do_iter_readv_writev+0x19f/0x320\n    [\u003c000000008f338ea2\u003e] do_iter_write+0x135/0x630\n    [\u003c000000008a3377a4\u003e] vfs_writev+0x12e/0x440\n    [\u003c00000000a6b5639a\u003e] do_writev+0x104/0x280\n    [\u003c00000000ccf065d8\u003e] do_syscall_64+0x3b/0x90\n    [\u003c00000000d776e329\u003e] 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-\u003elist, &napi-\u003erx_list);\n          \u003c-- While napi-\u003erx_count \u003c READ_ONCE(gro_normal_batch),\n          \u003c-- gro_normal_list() is not called, napi-\u003erx_list is not empty\n  \u003c-- not ask to complete the gro work, will cause memory leaks in\n  \u003c-- following tun_napi_del()\n...\ntun_napi_del()\n  netif_napi_del()\n    __netif_napi_del()\n    \u003c-- &napi-\u003erx_list is not empty, which caused memory leaks\n\nTo fix, add napi_complete() after napi_gro_frags().","modified":"2026-04-03T13:14:37.953290689Z","published":"2025-05-01T14:10:21.760Z","related":["SUSE-SU-2025:01918-1","SUSE-SU-2025:01966-1","SUSE-SU-2025:01983-1","SUSE-SU-2025:02173-1","SUSE-SU-2025:02262-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/49xxx/CVE-2022-49871.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/1118b2049d77ca0b505775fc1a8d1909cf19a7ec"},{"type":"WEB","url":"https://git.kernel.org/stable/c/223ef6a94e52331a6a7ef31e59921e0e82d2d40a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3401f964028ac941425b9b2c8ff8a022539ef44a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8b12a020b20a78f62bedc50f26db3bf4fadf8cb9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a4f73f6adc53fd7a3f9771cbc89a03ef39b0b755"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d7569302a7a52a9305d2fb054df908ff985553bb"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/49xxx/CVE-2022-49871.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2022-49871"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"90e33d45940793def6f773b2d528e9f3c84ffdc7"},{"fixed":"223ef6a94e52331a6a7ef31e59921e0e82d2d40a"},{"fixed":"a4f73f6adc53fd7a3f9771cbc89a03ef39b0b755"},{"fixed":"3401f964028ac941425b9b2c8ff8a022539ef44a"},{"fixed":"d7569302a7a52a9305d2fb054df908ff985553bb"},{"fixed":"8b12a020b20a78f62bedc50f26db3bf4fadf8cb9"},{"fixed":"1118b2049d77ca0b505775fc1a8d1909cf19a7ec"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2022-49871.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}