{"id":"CVE-2024-56661","summary":"tipc: fix NULL deref in cleanup_bearer()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ntipc: fix NULL deref in cleanup_bearer()\n\nsyzbot found [1] that after blamed commit, ub-\u003eubsock-\u003esk\nwas NULL when attempting the atomic_dec() :\n\natomic_dec(&tipc_net(sock_net(ub-\u003eubsock-\u003esk))-\u003ewq_count);\n\nFix this by caching the tipc_net pointer.\n\n[1]\n\nOops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN PTI\nKASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]\nCPU: 0 UID: 0 PID: 5896 Comm: kworker/0:3 Not tainted 6.13.0-rc1-next-20241203-syzkaller #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024\nWorkqueue: events cleanup_bearer\n RIP: 0010:read_pnet include/net/net_namespace.h:387 [inline]\n RIP: 0010:sock_net include/net/sock.h:655 [inline]\n RIP: 0010:cleanup_bearer+0x1f7/0x280 net/tipc/udp_media.c:820\nCode: 18 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 3c f7 99 f6 48 8b 1b 48 83 c3 30 e8 f0 e4 60 00 48 89 d8 48 c1 e8 03 \u003c42\u003e 80 3c 28 00 74 08 48 89 df e8 1a f7 99 f6 49 83 c7 e8 48 8b 1b\nRSP: 0018:ffffc9000410fb70 EFLAGS: 00010206\nRAX: 0000000000000006 RBX: 0000000000000030 RCX: ffff88802fe45a00\nRDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffc9000410f900\nRBP: ffff88807e1f0908 R08: ffffc9000410f907 R09: 1ffff92000821f20\nR10: dffffc0000000000 R11: fffff52000821f21 R12: ffff888031d19980\nR13: dffffc0000000000 R14: dffffc0000000000 R15: ffff88807e1f0918\nFS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 0000556ca050b000 CR3: 0000000031c0c000 CR4: 00000000003526f0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400","modified":"2026-04-16T04:30:51.582145437Z","published":"2024-12-27T15:06:23.928Z","related":["SUSE-SU-2025:01633-1","SUSE-SU-2025:0289-1","SUSE-SU-2025:0428-1","SUSE-SU-2025:0499-1","SUSE-SU-2025:0555-1","SUSE-SU-2025:0556-1","SUSE-SU-2025:0557-1","SUSE-SU-2025:0565-1","SUSE-SU-2025:0576-1","SUSE-SU-2025:0577-1","SUSE-SU-2025:0577-2","SUSE-SU-2025:1574-1","SUSE-SU-2025:20165-1","SUSE-SU-2025:20166-1","SUSE-SU-2025:20248-1","SUSE-SU-2025:20249-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/56xxx/CVE-2024-56661.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/07b569eda6fe6a1e83be5a587abee12d1303f95e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/754ec823ee53422361da7958a8c8bf3275426912"},{"type":"WEB","url":"https://git.kernel.org/stable/c/89ecda492d0a37fd00aaffc4151f1f44c26d93ac"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a771f349c95d3397636861a0a6462d4a7a7ecb25"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a852c82eda4991e21610837aaa160965be71f5cc"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b04d86fff66b15c07505d226431f808c15b1703c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/d1d4dfb189a115734bff81c411bc58d9e348db7d"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/56xxx/CVE-2024-56661.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-56661"},{"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":"4e69457f9dfae67435f3ccf29008768eae860415"},{"fixed":"d1d4dfb189a115734bff81c411bc58d9e348db7d"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"650ee9a22d7a2de8999fac2d45983597a0c22359"},{"fixed":"a771f349c95d3397636861a0a6462d4a7a7ecb25"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"d2a4894f238551eae178904e7f45af87577074fd"},{"fixed":"07b569eda6fe6a1e83be5a587abee12d1303f95e"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"d62d5180c036eeac09f80660edc7a602b369125f"},{"fixed":"754ec823ee53422361da7958a8c8bf3275426912"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"d00d4470bf8c4282617a3a10e76b20a9c7e4cffa"},{"fixed":"89ecda492d0a37fd00aaffc4151f1f44c26d93ac"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"e48b211c4c59062cb6dd6c2c37c51a7cc235a464"},{"fixed":"a852c82eda4991e21610837aaa160965be71f5cc"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6a2fa13312e51a621f652d522d7e2df7066330b6"},{"fixed":"b04d86fff66b15c07505d226431f808c15b1703c"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-56661.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"}]}