CVE-2026-43127

Summary

In the Linux kernel, the following vulnerability has been resolved: ntfs3: fix circular locking dependency in run_unpack_ex Syzbot reported a circular locking dependency between wnd->rw_lock (sbi->used.bitmap) and ni->file.run_lock. The deadlock scenario: 1. ntfs_extend_mft() takes ni->file.run_lock then wnd->rw_lock. 2. run_unpack_ex() takes wnd->rw_lock then tries to acquire ni->file.run_lock inside ntfs_refresh_zone(). This creates an AB-BA deadlock. Fix this by using down_read_trylock() instead of down_read() when acquiring run_lock in run_unpack_ex(). If the lock is contended, skip ntfs_refresh_zone() - the MFT zone will be refreshed on the next MFT operation. This breaks the circular dependency since we never block waiting for run_lock while holding wnd->rw_lock.

Impact & exploitability

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products we track (1)

Recommendation

Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.

Official patch: https://git.kernel.org/stable/c/08ce2fee1b869ecbfbd94e0eb2630e52203a2e03 ↗

Additional information

• NVD record
• https://git.kernel.org/stable/c/08ce2fee1b869ecbfbd94e0eb2630e52203a2e03Patch
• https://git.kernel.org/stable/c/b014372b62237521444ee51384549bdf48b79015Patch
• https://git.kernel.org/stable/c/b8d22d9d8260b0f4f4d8e2898c98037c9982ea66Patch
• https://git.kernel.org/stable/c/76016d15bbd90caa0ce7765fddf9bde8e943e601
• https://git.kernel.org/stable/c/d60f09d2d16c44a797d8cb67015cde2508720506