STABLE12-xdrmem-getbytes-20030321

See, for example:
http://web.mit.edu/kerberos/www/advisories/MITKRB5-SA-2003-003-xdr.txt
This source is unused but it seems like a good idea to patch it anyway.

(cherry picked from commit 7f4d43ac2f6d7b44a5f07be6e59d45bf9c6736dc)

diff --git a/src/rx/xdr_mem.c b/src/rx/xdr_mem.c
index 0047b37cf482208fadb814e4d5ca16bf0cdaaf41..a11cfa70e05f605461c9f604e7ef76089ae05e96 100644 (file)
--- a/src/rx/xdr_mem.c
+++ b/src/rx/xdr_mem.c
@@ -84,7 +84,7 @@ xdrmem_create(xdrs, addr, size, op)
        xdrs->x_op = op;
        xdrs->x_ops = &xdrmem_ops;
        xdrs->x_private = xdrs->x_base = addr;
-       xdrs->x_handy = size;
+       xdrs->x_handy = (size > INT_MAX) ? INT_MAX : size; /* XXX */
 }
 
 static void
@@ -98,12 +98,14 @@ xdrmem_getint32(xdrs, lp)
        register XDR *xdrs;
        afs_int32 *lp;
 {
-
-       if ((xdrs->x_handy -= sizeof(afs_int32)) < 0)
-               return (FALSE);
-       *lp = ntohl(*((afs_int32 *)(xdrs->x_private)));
-       xdrs->x_private += sizeof(afs_int32);
-       return (TRUE);
+    if (xdrs->x_handy -= sizeof(afs_int32))
+       return (FALSE);
+    else
+       xdrs->x_handy -= sizeof(afs_int32);
+
+    *lp = ntohl(*((afs_int32 *)(xdrs->x_private)));
+    xdrs->x_private += sizeof(afs_int32);
+    return (TRUE);
 }
 
 static bool_t
@@ -111,12 +113,14 @@ xdrmem_putint32(xdrs, lp)
        register XDR *xdrs;
        afs_int32 *lp;
 {
-
-       if ((xdrs->x_handy -= sizeof(afs_int32)) < 0)
-               return (FALSE);
-       *(afs_int32 *)xdrs->x_private = htonl(*lp);
-       xdrs->x_private += sizeof(afs_int32);
-       return (TRUE);
+    if (xdrs->x_handy -= sizeof(afs_int32))
+       eturn (FALSE);
+    else
+       xdrs->x_handy -= sizeof(afs_int32);
+    
+    *(afs_int32 *)xdrs->x_private = htonl(*lp);
+    xdrs->x_private += sizeof(afs_int32);
+    return (TRUE);
 }
 
 static bool_t
@@ -125,12 +129,14 @@ xdrmem_getbytes(xdrs, addr, len)
        caddr_t addr;
        register u_int len;
 {
-
-       if ((xdrs->x_handy -= len) < 0)
-               return (FALSE);
-       memcpy(addr, xdrs->x_private, len);
-       xdrs->x_private += len;
-       return (TRUE);
+    if (xdrs->x_handy < len)
+       return (FALSE);
+    else
+       xdrs->x_handy -= len;
+
+    memcpy(addr, xdrs->x_private, len);
+    xdrs->x_private += len;
+    return (TRUE);
 }
 
 static bool_t
@@ -139,12 +145,14 @@ xdrmem_putbytes(xdrs, addr, len)
        caddr_t addr;
        register u_int len;
 {
-
-       if ((xdrs->x_handy -= len) < 0)
-               return (FALSE);
-       memcpy(xdrs->x_private, addr, len);
-       xdrs->x_private += len;
-       return (TRUE);
+    if (xdrs->x_handy < len)
+       return (FALSE);
+    else
+       xdrs->x_handy -= len;
+
+    memcpy(xdrs->x_private, addr, len);
+    xdrs->x_private += len;
+    return (TRUE);
 }
 
 static u_int
@@ -177,7 +185,7 @@ xdrmem_inline(xdrs, len)
 {
        afs_int32 *buf = 0;
 
-       if (xdrs->x_handy >= len) {
+       if (len >= 0 && xdrs->x_handy >= len) {
                xdrs->x_handy -= len;
                buf = (afs_int32 *) xdrs->x_private;
                xdrs->x_private += len;