mount: robustify MS_MGC_VAL decoding
* mount.c (sys_mount): When printing mount flags, do not assume that
(flags & MS_MGC_MSK) == MS_MGC_VAL.
diff --git a/mount.c b/mount.c
index 7b30b37..2f7f0ca 100644
--- a/mount.c
+++ b/mount.c
@@ -35,17 +35,21 @@
SYS_FUNC(mount)
{
if (entering(tcp)) {
- int ignore_type = 0, ignore_data = 0;
+ bool ignore_type = false;
+ bool ignore_data = false;
+ bool old_magic = false;
unsigned long flags = tcp->u_arg[3];
/* Discard magic */
- if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
+ if ((flags & MS_MGC_MSK) == MS_MGC_VAL) {
flags &= ~MS_MGC_MSK;
+ old_magic = true;
+ }
if (flags & MS_REMOUNT)
- ignore_type = 1;
+ ignore_type = true;
else if (flags & (MS_BIND | MS_MOVE))
- ignore_type = ignore_data = 1;
+ ignore_type = ignore_data = true;
printpath(tcp, tcp->u_arg[0]);
tprints(", ");
@@ -59,7 +63,13 @@
printstr(tcp, tcp->u_arg[2], -1);
tprints(", ");
- printflags(mount_flags, tcp->u_arg[3], "MS_???");
+ if (old_magic) {
+ tprints("MS_MGC_VAL");
+ if (flags)
+ tprints("|");
+ }
+ if (flags || !old_magic)
+ printflags(mount_flags, flags, "MS_???");
tprints(", ");
if (ignore_data && tcp->u_arg[4])
