On Tue, Aug 23, 2022 at 12:48:48PM +0200, Michal Prívozník wrote:
> On 8/19/22 10:41, Erik Skultety wrote:
> > Coverity reports:
> > virNWFilterSnoopIPLeaseUpdate(virNWFilterSnoopIPLease *ipl,
> > time_t timeout)
> > {
> > if (timeout < ipl->timeout)
> > return; /* no take-backs */
> >
> > virNWFilterSnoopIPLeaseTimerDel(ipl);
> > >>> CID 396747: High impact quality (Y2K38_SAFETY)
> > >>> A "time_t" value is stored in an integer with too few bits
> > to accommodate it. The expression "timeout" is cast to
> > "unsigned int".
> > ipl->timeout = timeout;
> > virNWFilterSnoopIPLeaseTimerAdd(ipl);
> > }
> >
> > This is a safe fix, since time_t is just long int and scales
> > automatically with platform (more specifically it's 64bit on all
> > platforms we care about).
> >
> > Signed-off-by: Erik Skultety <eskultet@xxxxxxxxxx>
> > ---
> > src/nwfilter/nwfilter_dhcpsnoop.c | 6 +++---
> > 1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/src/nwfilter/nwfilter_dhcpsnoop.c b/src/nwfilter/nwfilter_dhcpsnoop.c
> > index a10a14cfc1..4133d4c672 100644
> > --- a/src/nwfilter/nwfilter_dhcpsnoop.c
> > +++ b/src/nwfilter/nwfilter_dhcpsnoop.c
> > @@ -146,7 +146,7 @@ struct _virNWFilterSnoopIPLease {
> > virSocketAddr ipAddress;
> > virSocketAddr ipServer;
> > virNWFilterSnoopReq * snoopReq;
> > - unsigned int timeout;
> > + time_t timeout;
> > /* timer list */
> > virNWFilterSnoopIPLease *prev;
> > virNWFilterSnoopIPLease *next;
> > @@ -1580,7 +1580,7 @@ virNWFilterSnoopLeaseFileWrite(int lfd, const char *ifkey,
> > return -1;
> >
> > /* time intf ip dhcpserver */
> > - lbuf = g_strdup_printf("%u %s %s %s\n", ipl->timeout, ifkey, ipstr, dhcpstr);
> > + lbuf = g_strdup_printf("%lu %s %s %s\n", ipl->timeout, ifkey, ipstr, dhcpstr);
>
> Doesn't this use of ->timeout need to be typecasted? I mean, we are not
> guaranteed that time_t is unsigned long. Elsewhere in the code we even
> typecast to long long.
Yes, this would fail on 32-bit builds I believe.
With regards,
Daniel
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