{"id":"DEBIAN-CVE-2024-35929","details":"In the Linux kernel, the following vulnerability has been resolved:  rcu/nocb: Fix WARN_ON_ONCE() in the rcu_nocb_bypass_lock()  For the kernels built with CONFIG_RCU_NOCB_CPU_DEFAULT_ALL=y and CONFIG_RCU_LAZY=y, the following scenarios will trigger WARN_ON_ONCE() in the rcu_nocb_bypass_lock() and rcu_nocb_wait_contended() functions:          CPU2                                               CPU11 kthread rcu_nocb_cb_kthread                                       ksys_write rcu_do_batch                                              vfs_write rcu_torture_timer_cb                                      proc_sys_write __kmem_cache_free                                         proc_sys_call_handler kmemleak_free                                             drop_caches_sysctl_handler delete_object_full                                        drop_slab __delete_object                                           shrink_slab put_object                                                lazy_rcu_shrink_scan call_rcu                                                  rcu_nocb_flush_bypass __call_rcu_commn                                            rcu_nocb_bypass_lock                                                             raw_spin_trylock(&rdp-\u003enocb_bypass_lock) fail                                                             atomic_inc(&rdp-\u003enocb_lock_contended); rcu_nocb_wait_contended                                     WARN_ON_ONCE(smp_processor_id() != rdp-\u003ecpu);  WARN_ON_ONCE(atomic_read(&rdp-\u003enocb_lock_contended))                                          |                             |_ _ _ _ _ _ _ _ _ _same rdp and rdp-\u003ecpu != 11_ _ _ _ _ _ _ _ _ __|  Reproduce this bug with \"echo 3 \u003e /proc/sys/vm/drop_caches\".  This commit therefore uses rcu_nocb_try_flush_bypass() instead of rcu_nocb_flush_bypass() in lazy_rcu_shrink_scan().  If the nocb_bypass queue is being flushed, then rcu_nocb_try_flush_bypass will return directly.","modified":"2026-09-15T09:02:56.767479167Z","published":"2024-05-19T11:15:48.993Z","upstream":["CVE-2024-35929"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2024-35929"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.8.9-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-35929.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.8.9-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-35929.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"}]}