CVE-2026-31597

Περιγραφή

In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix use-after-free in ocfs2_fault() when VM_FAULT_RETRY filemap_fault() may drop the mmap_lock before returning VM_FAULT_RETRY, as documented in mm/filemap.c: -If our return value has VM_FAULT_RETRY set, it-s because the mmap_lock may be dropped before doing I/O or by lock_folio_maybe_drop_mmap().- When this happens, a concurrent munmap() can call remove_vma() and free the vm_area_struct via RCU. The saved -vma- pointer in ocfs2_fault() then becomes a dangling pointer, and the subsequent trace_ocfs2_fault() call dereferences it -- a use-after-free. Fix this by saving ip_blkno as a plain integer before calling filemap_fault(), and removing vma from the trace event. Since ip_blkno is copied by value before the lock can be dropped, it remains valid regardless of what happens to the vma or inode afterward.