{"id":"DEBIAN-CVE-2026-64435","details":"In the Linux kernel, the following vulnerability has been resolved:  audit: Fix data races of skb_queue_len() readers on audit_queue  Multiple readers access audit_queue.qlen via skb_queue_len() without holding the queue lock or using READ_ONCE(), while kauditd writes to this field via the skb_dequeue() → __skb_unlink() path with WRITE_ONCE() protected by a spinlock. This constitutes data races.  All affected skb_queue_len(&audit_queue) call sites:   - kauditd_thread() wait_event_freezable() condition   - audit_receive_msg() AUDIT_GET handler (s.backlog assignment)   - audit_receive() backlog check   - audit_log_start() backlog check and pr_warn()  KCSAN reports the following conflicting access pattern (one example): ================================================================== BUG: KCSAN: data-race in audit_log_start / skb_dequeue  write (marked) to 0xffffffff8512ee20 of 4 bytes by task 661 on cpu 57:  skb_dequeue+0x70/0xf0  kauditd_send_queue+0x71/0x220  kauditd_thread+0x1cb/0x430  kthread+0x1c2/0x210  ret_from_fork+0x162/0x1a0  ret_from_fork_asm+0x1a/0x30  read to 0xffffffff8512ee20 of 4 bytes by task 36586 on cpu 1:  audit_log_start+0x2a0/0x6b0  audit_core_dumps+0x64/0xa0  do_coredump+0x14b/0x1260  get_signal+0xeb2/0xf70  arch_do_signal_or_restart+0x41/0x170  exit_to_user_mode_loop+0xa2/0x1c0  do_syscall_64+0x1a3/0x1c0  entry_SYSCALL_64_after_hwframe+0x76/0xe0  value changed: 0x00000001 -\u003e 0x00000000 ==================================================================  Resolve the race by switching to lockless helper skb_queue_len_lockless(), which internally uses READ_ONCE() and properly pairs with the WRITE_ONCE() write accesses already present on the writer side.  [PM: line length tweak]","modified":"2026-09-04T08:47:31.324955868Z","published":"2026-07-25T10:17:27.873Z","upstream":["CVE-2026-64435"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-64435"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.180-1"}]}],"versions":["6.1.106-1","6.1.106-2","6.1.106-3","6.1.112-1","6.1.115-1","6.1.119-1","6.1.123-1","6.1.124-1","6.1.128-1","6.1.129-1","6.1.133-1","6.1.135-1","6.1.137-1","6.1.139-1","6.1.140-1","6.1.147-1","6.1.148-1","6.1.153-1","6.1.158-1","6.1.159-1","6.1.162-1","6.1.164-1","6.1.170-1","6.1.170-2","6.1.170-3","6.1.172-1","6.1.174-1","6.1.176-1","6.1.177-1","6.1.27-1","6.1.37-1","6.1.38-1","6.1.38-2","6.1.38-2~bpo11+1","6.1.38-3","6.1.38-4","6.1.38-4~bpo11+1","6.1.52-1","6.1.55-1","6.1.55-1~bpo11+1","6.1.64-1","6.1.66-1","6.1.67-1","6.1.69-1","6.1.69-1~bpo11+1","6.1.76-1","6.1.76-1~bpo11+1","6.1.82-1","6.1.85-1","6.1.90-1","6.1.90-1~bpo11+1","6.1.94-1","6.1.94-1~bpo11+1","6.1.98-1","6.1.99-1"],"ecosystem_specific":{"urgency":"not 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