On Fri, 2018-06-29 at 14:42 -0400, Steve Dickson wrote: > From: Daniel Sands <dnsands@xxxxxxxxxx> > > The cause is that the xdr_putlong uses a long to store the > converted value, then passes it to fwrite as a byte buffer. > Only the first 4 bytes are written, which is okay for a LE > system after byteswapping, but writes all zeroes on BE systems. > > Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1261738 > > Signed-off-by: Steve Dickson <steved@xxxxxxxxxx> > --- > v2: Added bounds checking > Changed from unsigned to signed > > src/xdr_stdio.c | 14 +++++++++++--- > 1 file changed, 11 insertions(+), 3 deletions(-) > > diff --git a/src/xdr_stdio.c b/src/xdr_stdio.c > index 4410262..b902acd 100644 > --- a/src/xdr_stdio.c > +++ b/src/xdr_stdio.c > @@ -103,10 +103,12 @@ xdrstdio_getlong(xdrs, lp) > XDR *xdrs; > long *lp; > { > + int32_t mycopy; > > - if (fread(lp, sizeof(int32_t), 1, (FILE *)xdrs->x_private) > != 1) > + if (fread(&mycopy, sizeof(int32_t), 1, (FILE *)xdrs- > >x_private) != 1) > return (FALSE); > - *lp = (long)ntohl((u_int32_t)*lp); > + > + *lp = (long)ntohl(mycopy); > return (TRUE); > } > > @@ -115,8 +117,14 @@ xdrstdio_putlong(xdrs, lp) > XDR *xdrs; > const long *lp; > { > - long mycopy = (long)htonl((u_int32_t)*lp); > + int32_t mycopy; > + > +#if defined(_LP64) > + if ((*lp > INT32_MAX) || (*lp < INT32_MIN)) > + return (FALSE); The will work just fine if your cast is: int a; lp = (long)a; ...but it won't do the right thing for unsigned int b = UINT32_MAX; lp = (long)b; /* set lp to UINT32_MAX */ Since there us no dedicated xdrstdio_putulong() to use for unsigned integers, we need the check to work for both cases. For that reason, I think the above check either has to be: if (*lp == (long)((u_int32_t)*lp)) return (FALSE); ...or something uglier like if (*lp > UINT32_MAX || *lp < INT32_MIN) return (FALSE); > +#endif > > + mycopy = (int32_t)htonl((int32_t)*lp); > if (fwrite(&mycopy, sizeof(int32_t), 1, (FILE *)xdrs- > >x_private) != 1) > return (FALSE); > return (TRUE); -- Trond Myklebust CTO, Hammerspace Inc 4300 El Camino Real, Suite 105 Los Altos, CA 94022 www.hammer.space ��.n��������+%������w��{.n�����{��w��� jg��� �����ݢj����G���� ���j:+v���w�m������w�������h�����٥
