CVE-2026-68290 (GCVE-0-2026-68290)
Vulnerability from cvelistv5
Published
2026-08-10 12:02
Modified
2026-10-21 12:43
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: rds: tcp: unregister sysctl before tearing down listen socket rds_tcp_exit_net() frees the per-netns RDS TCP listen socket via rds_tcp_kill_sock() before unregistering the per-netns sysctl table. Since rds_tcp_skbuf_handler() derives the netns from rtn->rds_tcp_listen_sock->sk, a concurrent sysctl write can race with netns teardown and dereference the freed socket/sk. KASAN reports the race as: BUG: KASAN: slab-use-after-free in rds_tcp_skbuf_handler+0x2aa/0x2e0 rds_tcp_skbuf_handler net/rds/tcp.c:721 proc_sys_call_handler fs/proc/proc_sysctl.c vfs_write fs/read_write.c __x64_sys_pwrite64 fs/read_write.c Fix this by unregistering the RDS TCP sysctl table before calling rds_tcp_kill_sock(). unregister_net_sysctl_table() prevents new sysctl handlers from starting and waits for in-flight handlers to finish, so the listen socket can then be released safely. The fix was tested against the linked reproducer.
References
Impacted products
Vendor Product Version
Linux Linux Version: de8d6de0ee27be4b2b1e5b06f04aeacbabbba492
Version: 7f5611cbc4871c7fb1ad36c2e5a9edad63dca95c
Version: 7f5611cbc4871c7fb1ad36c2e5a9edad63dca95c
Version: 7f5611cbc4871c7fb1ad36c2e5a9edad63dca95c
Version: 33b3e09a489a31b30342b77cc55290f025d95c7e
Version: 6.12.10   ≤
Version: 6.6.160   ≤
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