execve: Use ugets for copying argument 0 to udata

The argument list gets squeezed in at the process memory top,
and if it is short, copying all 8 bytes might read above top.

Signed-off-by: Tormod Volden <debian.tormod@gmail.com>

diff --git a/Kernel/syscall_exec16.c b/Kernel/syscall_exec16.c
index a1d42ad..6575c15 100644 (file)
--- a/Kernel/syscall_exec16.c
+++ b/Kernel/syscall_exec16.c
@@ -210,7 +210,7 @@ arg_t _execve(void)
        nenvp = wargs((char *) (nargv), ebuf, NULL);
 
        // Fill in udata.u_name with Program invocation name
-       uget((void *) ugetw(nargv), udata.u_name, 8);
+       ugets((void *) ugetw(nargv), udata.u_name, 8);
        memcpy(udata.u_ptab->p_name, udata.u_name, 8);
 
        brelse(abuf);