Re: [PATCH] tty: limit TCSBRKP break duration
Greg Kroah-Hartman <[email protected]> Fri, 31 Jul 2026 17:04:40 +0200
| Newsgroups | org.kernel.vger.linux-serial,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <2026073157-expend-unzip-cad7@gregkh> |
On Fri, Jul 31, 2026 at 10:30:41PM +0800, Xincheng Wang wrote: > Hi Greg, > > Yes, it would still be user-visible. > > My concern is that tty_ioctl() first multiplies the TCSBRKP argument by > 100 before passing it to send_break(), whose duration argument is > unsigned int. For values above UINT_MAX / 100, the current behavior uses > the low 32 bits of the multiplied product, which can be a duration very > different from the requested interval. > > But I agree that rejecting or saturating that value would also change > current behavior. Would you be open to a fix for this, or would you > rather leave the path as-is? I lost all context here :( ANyway, keeping things as-is is always good, unless you know of a way the current stuff is broken and you can fix it without changing any existing users. user apis are hard... thanks, greg k-h