{"id":"CVE-2023-54112","summary":"kcm: Fix memory leak in error path of kcm_sendmsg()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nkcm: Fix memory leak in error path of kcm_sendmsg()\n\nsyzbot reported a memory leak like below:\n\nBUG: memory leak\nunreferenced object 0xffff88810b088c00 (size 240):\n  comm \"syz-executor186\", pid 5012, jiffies 4294943306 (age 13.680s)\n  hex dump (first 32 bytes):\n    00 89 08 0b 81 88 ff ff 00 00 00 00 00 00 00 00  ................\n    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................\n  backtrace:\n    [\u003cffffffff83e5d5ff\u003e] __alloc_skb+0x1ef/0x230 net/core/skbuff.c:634\n    [\u003cffffffff84606e59\u003e] alloc_skb include/linux/skbuff.h:1289 [inline]\n    [\u003cffffffff84606e59\u003e] kcm_sendmsg+0x269/0x1050 net/kcm/kcmsock.c:815\n    [\u003cffffffff83e479c6\u003e] sock_sendmsg_nosec net/socket.c:725 [inline]\n    [\u003cffffffff83e479c6\u003e] sock_sendmsg+0x56/0xb0 net/socket.c:748\n    [\u003cffffffff83e47f55\u003e] ____sys_sendmsg+0x365/0x470 net/socket.c:2494\n    [\u003cffffffff83e4c389\u003e] ___sys_sendmsg+0xc9/0x130 net/socket.c:2548\n    [\u003cffffffff83e4c536\u003e] __sys_sendmsg+0xa6/0x120 net/socket.c:2577\n    [\u003cffffffff84ad7bb8\u003e] do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n    [\u003cffffffff84ad7bb8\u003e] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80\n    [\u003cffffffff84c0008b\u003e] entry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nIn kcm_sendmsg(), kcm_tx_msg(head)-\u003elast_skb is used as a cursor to append\nnewly allocated skbs to 'head'. If some bytes are copied, an error occurred,\nand jumped to out_error label, 'last_skb' is left unmodified. A later\nkcm_sendmsg() will use an obsoleted 'last_skb' reference, corrupting the\n'head' frag_list and causing the leak.\n\nThis patch fixes this issue by properly updating the last allocated skb in\n'last_skb'.","modified":"2026-04-02T09:45:35.949980Z","published":"2025-12-24T13:06:34.854Z","related":["SUSE-SU-2026:0278-1","SUSE-SU-2026:0281-1","SUSE-SU-2026:0293-1","SUSE-SU-2026:0315-1","SUSE-SU-2026:0473-1","SUSE-SU-2026:20477-1","SUSE-SU-2026:20498-1","SUSE-SU-2026:20845-1","SUSE-SU-2026:20876-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/54xxx/CVE-2023-54112.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/16989de75497574b5fafd174c0c233d5a86858b7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/33db24ad811b3576a0c2f8862506763f2be925b0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/479c71cda14b3c3a6515773faa39055333eaa2b7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5e5554389397e98fafb9efe395d8b4830dd5f042"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8dc7eb757b1652b82725f32e0c89a1e9f6c0e13b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/97275339c34cfbccd65e87bc38fd910ae66c48ba"},{"type":"WEB","url":"https://git.kernel.org/stable/c/af8085e0fc3207ecbf8b9e7a635c790e36d058c6"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c821a88bd720b0046433173185fd841a100d44ad"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/54xxx/CVE-2023-54112.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-54112"},{"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":"ab7ac4eb9832e32a09f4e8042705484d2fb0aad3"},{"fixed":"8dc7eb757b1652b82725f32e0c89a1e9f6c0e13b"},{"fixed":"5e5554389397e98fafb9efe395d8b4830dd5f042"},{"fixed":"479c71cda14b3c3a6515773faa39055333eaa2b7"},{"fixed":"33db24ad811b3576a0c2f8862506763f2be925b0"},{"fixed":"97275339c34cfbccd65e87bc38fd910ae66c48ba"},{"fixed":"16989de75497574b5fafd174c0c233d5a86858b7"},{"fixed":"af8085e0fc3207ecbf8b9e7a635c790e36d058c6"},{"fixed":"c821a88bd720b0046433173185fd841a100d44ad"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-54112.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.6.0"},{"fixed":"4.14.326"}]},{"type":"ECOSYSTEM","events":[{"introduced":"4.15.0"},{"fixed":"4.19.295"}]},{"type":"ECOSYSTEM","events":[{"introduced":"4.20.0"},{"fixed":"5.4.257"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.5.0"},{"fixed":"5.10.195"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.132"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.54"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.5.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-54112.json"}}],"schema_version":"1.7.5"}