handle theoretical case of sigfillsz not being pow2-sized on some

architecture.
from miod

diff --git a/sys/kern/kern_exec.c b/sys/kern/kern_exec.c
index 1a69380..674c62a 100644 (file)
--- a/sys/kern/kern_exec.c
+++ b/sys/kern/kern_exec.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: kern_exec.c,v 1.222 2021/03/12 10:13:28 mpi Exp $     */
+/*     $OpenBSD: kern_exec.c,v 1.223 2021/03/16 16:32:22 deraadt Exp $ */
 /*     $NetBSD: kern_exec.c,v 1.75 1996/02/09 18:59:28 christos Exp $  */
 
 /*-
@@ -834,7 +834,7 @@ exec_sigcode_map(struct process *pr, struct emul *e)
        if (e->e_sigobject == NULL) {
                extern int sigfillsiz;
                extern u_char sigfill[];
-               size_t off;
+               size_t off, left;
                vaddr_t va;
                int r;
 
@@ -848,8 +848,12 @@ exec_sigcode_map(struct process *pr, struct emul *e)
                        return (ENOMEM);
                }
 
-               for (off = 0; off < round_page(sz); off += sigfillsiz)
-                       memcpy((caddr_t)va + off, sigfill, sigfillsiz);
+               for (off = 0, left = round_page(sz); left != 0;
+                   off += sigfillsiz) {
+                       size_t chunk = ulmin(left, sigfillsiz);
+                       memcpy((caddr_t)va + off, sigfill, chunk);
+                       left -= chunk;
+               }
                memcpy((caddr_t)va, e->e_sigcode, sz);
                uvm_unmap(kernel_map, va, va + round_page(sz));
        }