add check for wrapping of address + size in exec()

2015-12-20 00:04:52 +09:00 · 2015-12-20 00:04:52 +09:00 · 5625ae4973
parent 67a7f9597e
commit 5625ae4973
1 changed files with 2 additions and 0 deletions
--- a/exec.c
+++ b/exec.c
@ -44,6 +44,8 @@ exec(char *path, char **argv)
      continue;
    if(ph.memsz < ph.filesz)
      goto bad;
+    if(ph.vaddr + ph.memsz < ph.vaddr)
+      goto bad;
    if((sz = allocuvm(pgdir, sz, ph.vaddr + ph.memsz)) == 0)
      goto bad;
    if(ph.vaddr % PGSIZE != 0)