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.
A circular locking dependency vulnerability in the Linux kernel's NTFS3 filesystem driver allows potential deadlock conditions between wnd->rw_lock and ni->file.run_lock. The vulnerability is resolved by using non-blocking lock acquisition to prevent the AB-BA deadlock scenario.
تم اكتشاف ثغرة حلقة دائرية في قفل في برنامج تشغيل نظام ملفات NTFS3 بنواة Linux حيث يمكن أن يحدث جمود (deadlock) بين وحدات القفل المختلفة. يتم إصلاح المشكلة باستخدام محاولة قفل غير محجوبة لتجنب سيناريو الجمود AB-BA.
A circular locking dependency vulnerability in the Linux kernel's NTFS3 filesystem driver allows potential deadlock conditions between wnd->rw_lock and ni->file.run_lock. The vulnerability is resolved by using non-blocking lock acquisition to prevent the AB-BA deadlock scenario.
Update the Linux kernel to the latest patched version that includes the fix for CVE-2026-43127. Apply the patch that modifies run_unpack_ex() to use down_read_trylock() instead of down_read() when acquiring run_lock, allowing graceful handling of lock contention without blocking.
قم بتحديث نواة Linux إلى أحدث إصدار مصحح يتضمن إصلاح CVE-2026-43127. طبق التصحيح الذي يعدل run_unpack_ex() لاستخدام down_read_trylock() بدلاً من down_read() عند الحصول على run_lock، مما يسمح بمعالجة آمنة لتنازع الأقفال دون حجب.