workaround another sendmsg kernel bug on 64-bit machines

[musl] / src / network / sendmsg.c

diff --git a/src/network/sendmsg.c b/src/network/sendmsg.c
index 164c28d..5f08000 100644 (file)
--- a/src/network/sendmsg.c
+++ b/src/network/sendmsg.c
@@ -1,5 +1,7 @@
 #include <sys/socket.h>
 #include <limits.h>
+#include <string.h>
+#include <errno.h>
 #include "syscall.h"
 #include "libc.h"
 
@@ -7,10 +9,21 @@ ssize_t sendmsg(int fd, const struct msghdr *msg, int flags)
 {
 #if LONG_MAX > INT_MAX
        struct msghdr h;
+       struct cmsghdr chbuf[1024/sizeof(struct cmsghdr)+1], *c;
        if (msg) {
                h = *msg;
                h.__pad1 = h.__pad2 = 0;
                msg = &h;
+               if (h.msg_controllen) {
+                       if (h.msg_controllen > 1024) {
+                               errno = ENOMEM;
+                               return -1;
+                       }
+                       memcpy(chbuf, h.msg_control, h.msg_controllen);
+                       h.msg_control = chbuf;
+                       for (c=CMSG_FIRSTHDR(&h); c; c=CMSG_NXTHDR(&h,c))
+                               c->__pad1 = 0;
+               }
        }
 #endif
        return socketcall_cp(sendmsg, fd, msg, flags, 0, 0, 0);