The branch releng/14.3 has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=2bbc6677c6862d4dc1032c898037f3d2ab974f40
commit 2bbc6677c6862d4dc1032c898037f3d2ab974f40 Author: Konstantin Belousov <[email protected]> AuthorDate: 2025-11-28 15:57:22 +0000 Commit: Mark Johnston <[email protected]> CommitDate: 2026-01-26 16:49:26 +0000 vm_fault: only rely on PG_ZERO when the page was newly allocated Approved by: so Security: FreeBSD-EN-26:03.vm (cherry picked from commit cff67bc43df14d492ccc08ec92fddceadd069953) (cherry picked from commit 99f641267d449f26a2e13449964f29d17897c29f) --- sys/vm/vm_fault.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/sys/vm/vm_fault.c b/sys/vm/vm_fault.c index dd044d27f00f..64580c34c0a0 100644 --- a/sys/vm/vm_fault.c +++ b/sys/vm/vm_fault.c @@ -139,6 +139,7 @@ struct faultstate { vm_object_t object; vm_pindex_t pindex; vm_page_t m; + bool m_needs_zeroing; /* Top-level map object. */ vm_object_t first_object; @@ -265,6 +266,7 @@ static void vm_fault_deallocate(struct faultstate *fs) { + fs->m_needs_zeroing = true; vm_fault_page_release(&fs->m_cow); vm_fault_page_release(&fs->m); vm_object_pip_wakeup(fs->object); @@ -1172,7 +1174,7 @@ vm_fault_zerofill(struct faultstate *fs) /* * Zero the page if necessary and mark it valid. */ - if ((fs->m->flags & PG_ZERO) == 0) { + if (fs->m_needs_zeroing) { pmap_zero_page(fs->m); } else { VM_CNT_INC(v_ozfod); @@ -1286,6 +1288,7 @@ vm_fault_allocate(struct faultstate *fs) vm_waitpfault(dset, vm_pfault_oom_wait * hz); return (FAULT_RESTART); } + fs->m_needs_zeroing = (fs->m->flags & PG_ZERO) == 0; fs->oom_started = false; return (FAULT_CONTINUE); @@ -1553,6 +1556,7 @@ vm_fault(vm_map_t map, vm_offset_t vaddr, vm_prot_t fault_type, fs.fault_flags = fault_flags; fs.map = map; fs.lookup_still_valid = false; + fs.m_needs_zeroing = true; fs.oom_started = false; fs.nera = -1; fs.can_read_lock = true;
