{"schema_version":"1.9.0","id":"CVE-2024-26631","published":"2024-03-18T10:07:48.346Z","modified":"2026-08-12T03:51:47.082493865Z","related":["SUSE-SU-2024:3190-1","SUSE-SU-2024:3194-1","SUSE-SU-2024:3195-1","SUSE-SU-2024:3209-1","SUSE-SU-2024:3383-1","SUSE-SU-2024:3483-1","SUSE-SU-2025:20044-1","SUSE-SU-2025:20047-1","USN-6818-2","USN-6819-2"],"summary":"ipv6: mcast: fix data-race in ipv6_mc_down / mld_ifc_work","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: mcast: fix data-race in ipv6_mc_down / mld_ifc_work\n\nidev->mc_ifc_count can be written over without proper locking.\n\nOriginally found by syzbot [1], fix this issue by encapsulating calls\nto mld_ifc_stop_work() (and mld_gq_stop_work() for good measure) with\nmutex_lock() and mutex_unlock() accordingly as these functions\nshould only be called with mc_lock per their declarations.\n\n[1]\nBUG: KCSAN: data-race in ipv6_mc_down / mld_ifc_work\n\nwrite to 0xffff88813a80c832 of 1 bytes by task 3771 on cpu 0:\n mld_ifc_stop_work net/ipv6/mcast.c:1080 [inline]\n ipv6_mc_down+0x10a/0x280 net/ipv6/mcast.c:2725\n addrconf_ifdown+0xe32/0xf10 net/ipv6/addrconf.c:3949\n addrconf_notify+0x310/0x980\n notifier_call_chain kernel/notifier.c:93 [inline]\n raw_notifier_call_chain+0x6b/0x1c0 kernel/notifier.c:461\n __dev_notify_flags+0x205/0x3d0\n dev_change_flags+0xab/0xd0 net/core/dev.c:8685\n do_setlink+0x9f6/0x2430 net/core/rtnetlink.c:2916\n rtnl_group_changelink net/core/rtnetlink.c:3458 [inline]\n __rtnl_newlink net/core/rtnetlink.c:3717 [inline]\n rtnl_newlink+0xbb3/0x1670 net/core/rtnetlink.c:3754\n rtnetlink_rcv_msg+0x807/0x8c0 net/core/rtnetlink.c:6558\n netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2545\n rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6576\n netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]\n netlink_unicast+0x589/0x650 net/netlink/af_netlink.c:1368\n netlink_sendmsg+0x66e/0x770 net/netlink/af_netlink.c:1910\n ...\n\nwrite to 0xffff88813a80c832 of 1 bytes by task 22 on cpu 1:\n mld_ifc_work+0x54c/0x7b0 net/ipv6/mcast.c:2653\n process_one_work kernel/workqueue.c:2627 [inline]\n process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2700\n worker_thread+0x525/0x730 kernel/workqueue.c:2781\n ...","affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"07a7a183f22cf1e3ce5ed336fe62a6248a2f6738"},{"fixed":"75ddcd741d2a30696f5893bc71a9d28f4ef22311"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"2d9a93b4902be6a5504b5941dd15e9cd776aadca"},{"fixed":"62b3387beef11738eb6ce667601a28fa089fa02c"},{"fixed":"380540bb06bb1d1b12bdc947d1b8f56cda6b5663"},{"fixed":"3cc283fd16fba72e2cefe3a6f48d7a36b0438900"},{"fixed":"3bb5849675ae1d592929798a2b37ea450879c855"},{"fixed":"2e7ef287f07c74985f1bf2858bedc62bd9ebf155"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-26631.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.13.0"},{"fixed":"5.15.148"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.75"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.14"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.7.2"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-26631.json"}}],"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/2e7ef287f07c74985f1bf2858bedc62bd9ebf155"},{"type":"WEB","url":"https://git.kernel.org/stable/c/380540bb06bb1d1b12bdc947d1b8f56cda6b5663"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3bb5849675ae1d592929798a2b37ea450879c855"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3cc283fd16fba72e2cefe3a6f48d7a36b0438900"},{"type":"WEB","url":"https://git.kernel.org/stable/c/62b3387beef11738eb6ce667601a28fa089fa02c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/75ddcd741d2a30696f5893bc71a9d28f4ef22311"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/26xxx/CVE-2024-26631.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-26631"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/26xxx/CVE-2024-26631.json"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}