cbcvebase.
CVE-2021-47493
published 2024-05-22

CVE-2021-47493: In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix race between searching chunks and release journal_head from buffer_head…

PriorityP416medium4.7CVSS 3.1
AVLACHPRLUINSUCNINAH
EPSS
0.17%
6.9th percentile
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->b_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.

Affected

18 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.15.3-1 (bookworm)linux 5.15.3-1 (bookworm)
linuxlinux——
linuxlinux>= ccd979bdbce9fba8412beb3f1de68a9d0171b12c < 5043fbd294f5909a080ade0f04b70a4da9e122b75043fbd294f5909a080ade0f04b70a4da9e122b7
linuxlinux>= ccd979bdbce9fba8412beb3f1de68a9d0171b12c < 2e382600e8856ea654677b5134ee66e03ea72bc22e382600e8856ea654677b5134ee66e03ea72bc2
linuxlinux>= ccd979bdbce9fba8412beb3f1de68a9d0171b12c < 6f1b228529ae49b0f85ab89bcdb6c365df4015586f1b228529ae49b0f85ab89bcdb6c365df401558
linuxlinux_kernel< 5.10.775.10.77
linuxlinux_kernel——
linuxlinux_kernel——
linuxlinux_kernel——
linuxlinux_kernel——
linuxlinux_kernel——
linuxlinux_kernel——
linuxlinux_kernel——
linuxlinux_kernel>= 0 < 5.10.84-15.10.84-1
linuxlinux_kernel>= 0 < 5.15.3-15.15.3-1
linuxlinux_kernel>= 0 < 5.15.3-15.15.3-1
linuxlinux_kernel>= 0 < 5.15.3-15.15.3-1
linuxlinux_kernel>= 5.11 < 5.14.165.14.16

CVSS provenance

nvdv3.14.7MEDIUMCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
osv4.7MEDIUM
vendor_debian4.7MEDIUM
vendor_redhat4.7MEDIUM
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