ipc_msg.c: fix multiple personalities support in msgrcv ipc subcall

When msgrcv syscall is an ipc subcall, msgp (pointer to struct msgbuf)
and msgtyp (message type) syscall arguments are passed via proxy
structure which definition significantly depends on tracee's
wordsize.

* ipc_msg.c (fetch_msgrcv_args): New function.
(sys_msgrcv): Use it.

diff --git a/ipc_msg.c b/ipc_msg.c
index fb126f5384eac921cdf3191d049bbc5dcfd1eac0..5052eacea8b73c100d9abc5b40a76666079630eb 100644 (file)
--- a/ipc_msg.c
+++ b/ipc_msg.c
@@ -81,22 +81,35 @@ tprint_msgrcv(struct tcb *tcp, const long addr, const unsigned long count,
        tprintf("%ld, ", msgtyp);
 }
 
+static int
+fetch_msgrcv_args(struct tcb *tcp, const long addr, long *pair)
+{
+       if (current_wordsize == sizeof(long)) {
+               if (umoven_or_printaddr(tcp, addr, 2 * sizeof(long), pair))
+                       return -1;
+       } else {
+               unsigned int tmp[2];
+
+               if (umove_or_printaddr(tcp, addr, &tmp))
+                       return -1;
+               pair[0] = tmp[0];
+               pair[1] = tmp[1];
+       }
+       return 0;
+}
+
 SYS_FUNC(msgrcv)
 {
        if (entering(tcp)) {
                tprintf("%d, ", (int) tcp->u_arg[0]);
        } else {
                if (indirect_ipccall(tcp)) {
-                       struct ipc_wrapper {
-                               struct msgbuf *msgp;
-                               long msgtyp;
-                       } tmp;
+                       long pair[2];
 
-                       if (umove_or_printaddr(tcp, tcp->u_arg[3], &tmp))
+                       if (fetch_msgrcv_args(tcp, tcp->u_arg[3], pair))
                                tprintf(", %lu, ", tcp->u_arg[1]);
                        else
-                               tprint_msgrcv(tcp, (long) tmp.msgp,
-                                       tcp->u_arg[1], tmp.msgtyp);
+                               tprint_msgrcv(tcp, pair[0], tcp->u_arg[1], pair[1]);
                        printflags(ipc_msg_flags, tcp->u_arg[2], "MSG_???");
                } else {
                        tprint_msgrcv(tcp, tcp->u_arg[1],