On Tue, Aug 23, 2022 at 18:22:37 +0200, 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);
> }
>
> Given that it doesn't make sense for a timeout to be negative, let's
> store it as unsigned long long and typecast all affected time_t
> occurrences accordingly. Since the affected places only ever get the
> current time which is not going to be negative (unless it's year 2038
> and a 32bit architecture) we can safely cast them.
>
> Signed-off-by: Erik Skultety <eskultet@xxxxxxxxxx>
> ---
> src/nwfilter/nwfilter_dhcpsnoop.c | 12 +++++++-----
> 1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/src/nwfilter/nwfilter_dhcpsnoop.c b/src/nwfilter/nwfilter_dhcpsnoop.c
> index 18812c0b20..0977951be1 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;
> + unsigned long long timeout;
[1]
> /* timer list */
> virNWFilterSnoopIPLease *prev;
> virNWFilterSnoopIPLease *next;
> @@ -415,7 +415,8 @@ virNWFilterSnoopIPLeaseInstallRule(virNWFilterSnoopIPLease *ipl,
> * virNWFilterSnoopIPLeaseUpdate - update the timeout on an IP lease
> */
> static void
> -virNWFilterSnoopIPLeaseUpdate(virNWFilterSnoopIPLease *ipl, time_t timeout)
> +virNWFilterSnoopIPLeaseUpdate(virNWFilterSnoopIPLease *ipl,
> + unsigned long long timeout)
> {
> if (timeout < ipl->timeout)
> return; /* no take-backs */
> @@ -447,7 +448,7 @@ virNWFilterSnoopIPLeaseGetByIP(virNWFilterSnoopIPLease *start,
> static unsigned int
> virNWFilterSnoopReqLeaseTimerRun(virNWFilterSnoopReq *req)
> {
> - time_t now = time(0);
> + unsigned long long now = time(0);
This should also use NULL instead of 0.
> bool is_last = false;
>
> /* protect req->start */
> @@ -1580,7 +1581,8 @@ 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("%llu %s %s %s\n",
> + ipl->timeout, ifkey, ipstr, dhcpstr);
> len = strlen(lbuf);
>
> if (safewrite(lfd, lbuf, len) != len) {
> @@ -1737,7 +1739,7 @@ virNWFilterSnoopLeaseFileLoad(void)
> }
> ln++;
> /* key len 54 = "VMUUID"+'-'+"MAC" */
> - if (sscanf(line, "%u %54s %15s %15s", &ipl.timeout,
> + if (sscanf(line, "%llu %54s %15s %15s", &ipl.timeout,
> ifkey, ipstr, srvstr) < 4) {
> virReportError(VIR_ERR_INTERNAL_ERROR,
> _("virNWFilterSnoopLeaseFileLoad lease file "
It feels to me that using a temporary unsigned long long variable to do
the sscanf and store everything in a time_t [1] would look more
appropriate as there shouldn't be a problem with time_t itself, right?
