{"id":"CVE-2026-74563","summary":"rds: tcp: hold the RCU lock across ipv6_chk_addr() in rds_tcp_laddr_check()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nrds: tcp: hold the RCU lock across ipv6_chk_addr() in rds_tcp_laddr_check()\n\nrds_tcp_laddr_check() looks up a scoped IPv6 interface with\ndev_get_by_index_rcu(), drops the RCU read-side lock, and only then\npasses the bare struct net_device * into ipv6_chk_addr().\n\ndev_get_by_index_rcu() only keeps the device alive within the same RCU\nread-side section. After rcu_read_unlock(), a concurrent RTM_DELLINK can\nfree the net_device; ipv6_chk_addr() then dereferences the stale pointer\nin __ipv6_chk_addr_and_flags() (e.g. l3mdev_master_dev_rcu(dev)), reading\nfreed memory.\n\nKeep the RCU read-side lock held across the ipv6_chk_addr() call instead\nof dropping it right after the lookup, so the device cannot be freed\nwhile it is in use.\n\n  BUG: KASAN: slab-use-after-free in __ipv6_chk_addr_and_flags (... net/ipv6/addrconf.c:1998)\n  Read of size 8 at addr ffff8880106ec000 by task exploit/153\n  Call Trace:\n   ...\n   kasan_report (mm/kasan/report.c:595)\n   __ipv6_chk_addr_and_flags (... net/ipv6/addrconf.c:1998)\n   ipv6_chk_addr (net/ipv6/addrconf.c:2031 net/ipv6/addrconf.c:1972)\n   rds_tcp_laddr_check (net/rds/tcp.c:370)\n   rds_bind (net/rds/bind.c:248)\n   __sys_bind (net/socket.c:1920)\n   __x64_sys_bind (net/socket.c:1956)\n   do_syscall_64 (arch/x86/entry/syscall_64.c:63)\n   entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)","modified":"2026-09-14T18:26:51.253183811Z","published":"2026-08-15T12:28:05.768Z","related":["SUSE-SU-2026:23477-1","SUSE-SU-2026:23481-1","SUSE-SU-2026:4120-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74563.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/76dd48886eeeb5fcf2b837d2f4c3d17eebeac9ef"},{"type":"WEB","url":"https://git.kernel.org/stable/c/78f75d632f74b8de0f081a128588f7c37d0d1164"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8398bc477d3cb3e2b018a5aaac2bec0f69acda30"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b1d480fce05f857dc438080cd8c9244b84a83494"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ba95bce5dfe6e2ef602a87e0557225f2934ccb5c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c4933624a6f416ecfcc31ab58d585da1207a0597"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f0d1fb05d70c8a561cd8d0473bcacafa2fc137ff"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f8a8977af2134a1d91e5f9773cb7d9d53278c830"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74563.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74563"},{"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":"eee2fa6ab3225192d6d894c54a6fb02ac9efdff6"},{"fixed":"f8a8977af2134a1d91e5f9773cb7d9d53278c830"},{"fixed":"ba95bce5dfe6e2ef602a87e0557225f2934ccb5c"},{"fixed":"c4933624a6f416ecfcc31ab58d585da1207a0597"},{"fixed":"76dd48886eeeb5fcf2b837d2f4c3d17eebeac9ef"},{"fixed":"f0d1fb05d70c8a561cd8d0473bcacafa2fc137ff"},{"fixed":"b1d480fce05f857dc438080cd8c9244b84a83494"},{"fixed":"8398bc477d3cb3e2b018a5aaac2bec0f69acda30"},{"fixed":"78f75d632f74b8de0f081a128588f7c37d0d1164"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74563.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.19.0"},{"fixed":"5.10.265"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.216"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.183"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.151"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.103"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.44"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.8"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74563.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}