Fix ILP32 personality struct cmsghdr decoding on LP64 architectures

* net.c (union_cmsghdr): New union.
[SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4] (cmsghdr32): New structure.
(printcmsghdr): Properly handle the case of current_wordsize < sizeof(long).

diff --git a/net.c b/net.c
index 40a18d021eddc71320a8739da3396d1b5140c19b..c235116c5abe264eac4e4c82c5dd62f04b1ed334 100644 (file)
--- a/net.c
+++ b/net.c
@@ -341,54 +341,99 @@ printsock(struct tcb *tcp, long addr, int addrlen)
 #if HAVE_SENDMSG
 #include "xlat/scmvals.h"
 
+#if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
+struct cmsghdr32 {
+       uint32_t cmsg_len;
+       int cmsg_level;
+       int cmsg_type;
+};
+#endif
+
+typedef union {
+       char *buf;
+       struct cmsghdr *cmsg;
+#if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
+       struct cmsghdr32 *cmsg32;
+#endif
+} union_cmsghdr;
+
 static void
 printcmsghdr(struct tcb *tcp, unsigned long addr, unsigned long len)
 {
-       struct cmsghdr *cmsg = len < sizeof(struct cmsghdr) ?
-                              NULL : malloc(len);
-       if (cmsg == NULL || umoven(tcp, addr, len, (char *) cmsg) < 0) {
+       union_cmsghdr u;
+       size_t cmsg_size;
+       unsigned long cmsg_len;
+       int cmsg_level;
+       int cmsg_type;
+
+       cmsg_size =
+#if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
+               (current_wordsize < sizeof(long)) ? sizeof(struct cmsghdr32) :
+#endif
+                       sizeof(struct cmsghdr);
+
+       u.buf = len < cmsg_size ? NULL : malloc(len);
+       if (!u.buf || umoven(tcp, addr, len, u.buf) < 0) {
                tprintf(", msg_control=%#lx", addr);
-               free(cmsg);
+               free(u.buf);
                return;
        }
 
-       tprintf(", {cmsg_len=%u, cmsg_level=", (unsigned) cmsg->cmsg_len);
-       printxval(socketlayers, cmsg->cmsg_level, "SOL_???");
+       cmsg_len =
+#if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
+               (current_wordsize < sizeof(long)) ? u.cmsg32->cmsg_len :
+#endif
+                       u.cmsg->cmsg_len;
+       cmsg_level =
+#if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
+               (current_wordsize < sizeof(long)) ? u.cmsg32->cmsg_level :
+#endif
+                       u.cmsg->cmsg_level;
+       cmsg_type =
+#if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
+               (current_wordsize < sizeof(long)) ? u.cmsg32->cmsg_type :
+#endif
+                       u.cmsg->cmsg_type;
+
+       tprintf(", {cmsg_len=%lu, cmsg_level=", cmsg_len);
+       printxval(socketlayers, cmsg_level, "SOL_???");
        tprints(", cmsg_type=");
 
-       if (cmsg->cmsg_level == SOL_SOCKET) {
-               unsigned long cmsg_len;
+       if (cmsg_len > len)
+               cmsg_len = len;
 
-               printxval(scmvals, cmsg->cmsg_type, "SCM_???");
-               cmsg_len = (len < cmsg->cmsg_len) ? len : cmsg->cmsg_len;
+       if (cmsg_level == SOL_SOCKET) {
+               printxval(scmvals, cmsg_type, "SCM_???");
 
-               if (cmsg->cmsg_type == SCM_RIGHTS
-                   && CMSG_LEN(sizeof(int)) <= cmsg_len) {
-                       int *fds = (int *) CMSG_DATA(cmsg);
+               if (cmsg_type == SCM_RIGHTS
+                   && cmsg_size + sizeof(int) <= cmsg_len) {
+                       int *fds = (int *) (u.buf + cmsg_size);
                        int first = 1;
 
                        tprints(", {");
-                       while ((char *) fds < ((char *) cmsg + cmsg_len)) {
+                       while ((char *) fds < (u.buf + cmsg_len)) {
                                if (!first)
                                        tprints(", ");
                                printfd(tcp, *fds++);
                                first = 0;
                        }
                        tprints("}}");
-                       free(cmsg);
+                       free(u.buf);
                        return;
                }
-               if (cmsg->cmsg_type == SCM_CREDENTIALS
-                   && CMSG_LEN(sizeof(struct ucred)) <= cmsg_len) {
-                       struct ucred *uc = (struct ucred *) CMSG_DATA(cmsg);
+               if (cmsg_type == SCM_CREDENTIALS
+                   && cmsg_size + sizeof(struct ucred) <= cmsg_len) {
+                       struct ucred *uc = (void *) (u.buf + cmsg_size);
 
                        tprintf("{pid=%ld, uid=%ld, gid=%ld}}",
                                (long)uc->pid, (long)uc->uid, (long)uc->gid);
-                       free(cmsg);
+                       free(u.buf);
                        return;
                }
+       } else {
+               tprintf("%u", cmsg_type);
        }
-       free(cmsg);
+       free(u.buf);
        tprints(", ...}");
 }