> > On Wed, Mar 20, 2019 at 02:51:29PM +0000, Frediano Ziglio wrote: > > Although id is not supposed to be big prevent possible > > warning/overflow. > > > > Signed-off-by: Frediano Ziglio <fziglio@xxxxxxxxxx> > > --- > > server/red-worker.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > This was signaled by Christophe Fergeau > > > > diff --git a/server/red-worker.c b/server/red-worker.c > > index 8051d1e4..a25a0cd8 100644 > > --- a/server/red-worker.c > > +++ b/server/red-worker.c > > @@ -1291,7 +1291,7 @@ RedWorker* red_worker_new(QXLInstance *qxl, > > worker->zlib_glz_state = reds_get_zlib_glz_state(reds); > > worker->driver_cap_monitors_config = 0; > > char worker_str[SPICE_STAT_NODE_NAME_MAX]; > > - sprintf(worker_str, "display[%d]", worker->qxl->id); > > + snprintf(worker_str, sizeof(worker_str), "display[%d]", > > worker->qxl->id); > > You pointed out that in the protocol, the id is 8 bits, so I'd change to > worker->qxl->id & 0xff while at it. > > Note that with SPICE_STAT_NODE_NAME_MAX (which is 20), you can > still get snprintf to misbehave: > "display[]" is 9 bytes > %d may need 11 bytes to be printed (if id is less than (unsigned > int)-4000000000) > so we'd be need 20 bytes in the buffer plus the trailing \0. > > Christophe > Your patch was better and it has a better explanation. The number you brought as example is weird! It does not fit into a 32 bit so cannot be worker->qxl->id. As we currently support only architectures where int is a 32 bit the (unsigned int)whatever will fit into 10 characters however formatting with %d will be converted to signed (so int) which won't fit in 10 characters (with the additional sign it requires 11 characters). Frediano _______________________________________________ Spice-devel mailing list Spice-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/spice-devel