diff options
Diffstat (limited to 'mm/memory.c')
-rw-r--r-- | mm/memory.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/mm/memory.c b/mm/memory.c index 19e0ae9..9aefaae 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -999,17 +999,15 @@ struct page *follow_page(struct vm_area_struct *vma, unsigned long address, goto no_page_table; ptep = pte_offset_map_lock(mm, pmd, address, &ptl); - if (!ptep) - goto out; pte = *ptep; if (!pte_present(pte)) - goto unlock; + goto no_page; if ((flags & FOLL_WRITE) && !pte_write(pte)) goto unlock; page = vm_normal_page(vma, address, pte); if (unlikely(!page)) - goto unlock; + goto bad_page; if (flags & FOLL_GET) get_page(page); @@ -1024,6 +1022,15 @@ unlock: out: return page; +bad_page: + pte_unmap_unlock(ptep, ptl); + return ERR_PTR(-EFAULT); + +no_page: + pte_unmap_unlock(ptep, ptl); + if (!pte_none(pte)) + return page; + /* Fall through to ZERO_PAGE handling */ no_page_table: /* * When core dumping an enormous anonymous area that nobody @@ -1159,6 +1166,8 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, cond_resched(); } + if (IS_ERR(page)) + return i ? i : PTR_ERR(page); if (pages) { pages[i] = page; |