CVE-2024-53155: ocfs2: fix uninitialized value in ocfs2_file_read_iter()

Severity: high (CVSS 7.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-12-24 · updated 2026-06-17
Weakness: CWE-908

Description

In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix uninitialized value in ocfs2_file_read_iter() Syzbot has reported the following KMSAN splat: BUG: KMSAN: uninit-value in ocfs2_file_read_iter+0x9a4/0xf80 ocfs2_file_read_iter+0x9a4/0xf80 __io_read+0x8d4/0x20f0 io_read+0x3e/0xf0 io_issue_sqe+0x42b/0x22c0 io_wq_submit_work+0xaf9/0xdc0 io_worker_handle_work+0xd13/0x2110 io_wq_worker+0x447/0x1410 ret_from_fork+0x6f/0x90 ret_from_fork_asm+0x1a/0x30 Uninit was created at: __alloc_pages_noprof+0x9a7/0xe00 alloc_pages_mpol_noprof+0x299/0x990 alloc_pages_noprof+0x1bf/0x1e0 allocate_slab+0x33a/0x1250 ___slab_alloc+0x12ef/0x35e0 kmem_cache_alloc_bulk_noprof+0x486/0x1330 __io_alloc_req_refill+0x84/0x560 io_submit_sqes+0x172f/0x2f30 __se_sys_io_uring_enter+0x406/0x41c0 __x64_sys_io_uring_enter+0x11f/0x1a0 x64_sys_call+0x2b54/0x3ba0 do_syscall_64+0xcd/0x1e0 entry_SYSCALL_64_after_hwframe+0x77/0x7f Since an instance of 'struct kiocb' may be passed from the block layer with 'private' field uninitialized, introduce 'ocfs2_iocb_init_rw_locked()' and use it from where 'ocfs2_dio_end_io()' might take care, i.e. in 'ocfs2_file_read_iter()' and 'ocfs2_file_write_iter()'.

Affected products

Linux kernel: from 2.6.22 before 4.19.325; from 4.20 before 5.4.287; from 5.5 before 5.10.231; from 5.11 before 5.15.174; from 5.16 before 6.1.120; from 6.2 before 6.6.64 — fixed in 4.19.325, 5.10.231, 5.15.174, 5.4.287, 6.1.120, 6.11.11

How to fix

Upgrade to a fixed version: Linux kernel 4.19.325, 5.10.231, 5.15.174, 5.4.287. Check the vendor advisory for mitigations.

References

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