> -----Original Message----- > From: Pavel Machek <pavel@xxxxxxx> > Sent: Thursday, November 21, 2019 2:35 AM > To: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > Cc: linux-kernel@xxxxxxxxxxxxxxx; stable@xxxxxxxxxxxxxxx; Williams, Mitch A > <mitch.a.williams@xxxxxxxxx>; Bowers, AndrewX <andrewx.bowers@xxxxxxxxx>; > Kirsher, Jeffrey T <jeffrey.t.kirsher@xxxxxxxxx>; Sasha Levin > <sashal@xxxxxxxxxx> > Subject: Re: [PATCH 4.19 079/422] i40e: use correct length for strncpy > > Hi! > > > From: Mitch Williams <mitch.a.williams@xxxxxxxxx> > > > > [ Upstream commit 7eb74ff891b4e94b8bac48f648a21e4b94ddee64 ] > > > > Caught by GCC 8. When we provide a length for strncpy, we should not > > include the terminating null. So we must tell it one less than the size > > of the destination buffer. > > > +++ b/drivers/net/ethernet/intel/i40e/i40e_ptp.c > > @@ -694,7 +694,8 @@ static long i40e_ptp_create_clock(struct i40e_pf *pf) > > if (!IS_ERR_OR_NULL(pf->ptp_clock)) > > return 0; > > > > - strncpy(pf->ptp_caps.name, i40e_driver_name, sizeof(pf->ptp_caps.name)); > > + strncpy(pf->ptp_caps.name, i40e_driver_name, > > + sizeof(pf->ptp_caps.name) - 1); > > pf->ptp_caps.owner = THIS_MODULE; > > pf->ptp_caps.max_adj = 999999999; > > pf->ptp_caps.n_ext_ts = 0; > > So... pf is allocated with kzalloc, which will provide the null > termination... so the code is okay. > > On the other hand, the = 0 below is unneeded by the same logic, so > this is a bit confusing. > > Best regards, > Pavel Thanks for catching this, Pavel. Aleksandr Loktionov owns this driver now. He can get this taken care of. -Mitch > -- > (english) http://www.livejournal.com/~pavelmachek > (cesky, pictures) > http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
