{"id":"DEBIAN-CVE-2021-47493","details":"In the Linux kernel, the following vulnerability has been resolved:  ocfs2: fix race between searching chunks and release journal_head from buffer_head  Encountered a race between ocfs2_test_bg_bit_allocatable() and jbd2_journal_put_journal_head() resulting in the below vmcore.    PID: 106879  TASK: ffff880244ba9c00  CPU: 2   COMMAND: \"loop3\"   Call trace:     panic     oops_end     no_context     __bad_area_nosemaphore     bad_area_nosemaphore     __do_page_fault     do_page_fault     page_fault       [exception RIP: ocfs2_block_group_find_clear_bits+316]     ocfs2_block_group_find_clear_bits [ocfs2]     ocfs2_cluster_group_search [ocfs2]     ocfs2_search_chain [ocfs2]     ocfs2_claim_suballoc_bits [ocfs2]     __ocfs2_claim_clusters [ocfs2]     ocfs2_claim_clusters [ocfs2]     ocfs2_local_alloc_slide_window [ocfs2]     ocfs2_reserve_local_alloc_bits [ocfs2]     ocfs2_reserve_clusters_with_limit [ocfs2]     ocfs2_reserve_clusters [ocfs2]     ocfs2_lock_refcount_allocators [ocfs2]     ocfs2_make_clusters_writable [ocfs2]     ocfs2_replace_cow [ocfs2]     ocfs2_refcount_cow [ocfs2]     ocfs2_file_write_iter [ocfs2]     lo_rw_aio     loop_queue_work     kthread_worker_fn     kthread     ret_from_fork  When ocfs2_test_bg_bit_allocatable() called bh2jh(bg_bh), the bg_bh-\u003eb_private NULL as jbd2_journal_put_journal_head() raced and released the jounal head from the buffer head.  Needed to take bit lock for the bit 'BH_JournalHead' to fix this race.","modified":"2026-09-15T09:02:35.963093828Z","published":"2024-05-22T09:15:11.100Z","upstream":["CVE-2021-47493"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2021-47493"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.15.3-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47493.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.15.3-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47493.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.15.3-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47493.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}