[PATCH] Fix MADV_REMOVE protection checking

madvise_remove needs to respect file and mmap protections. Signed-off-by: Hugh Dickins <hugh@veritas.com> [ Will the real CVE-2006-1524 stand up, please.. ] Signed-off-by: Linus Torvalds <torvalds@osdl.org>
SchmErik · Apr 18, 2006 · 69cf0fa · 69cf0fa
1 parent e14d95f
commit 69cf0fa
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/mm/madvise.c b/mm/madvise.c
@@ -168,6 +168,9 @@ static long madvise_remove(struct vm_area_struct *vma,
 			return -EINVAL;
 	}
 
+	if ((vma->vm_flags & (VM_SHARED|VM_WRITE)) != (VM_SHARED|VM_WRITE))
+		return -EACCES;
+
 	mapping = vma->vm_file->f_mapping;
 
 	offset = (loff_t)(start - vma->vm_start)