In the Linux kernel, the following vulnerability has been resolved: lib/iov_iter: fix to increase non slab folio refcount When testing EROFS file-backed mount over v9fs on qemu, I encountered a fol…

Summary

In the Linux kernel, the following vulnerability has been resolved: lib/iov_iter: fix to increase non slab folio refcount When testing EROFS file-backed mount over v9fs on qemu, I encountered a folio UAF issue. The page sanity check reports the following call trace. The root cause is that pages in bvec are coalesced across a folio bounary. The refcount of all non-slab folios should be increased to ensure p9_releas_pages can put them correctly. BUG: Bad page state in process md5sum pfn:183…