On Wed, Jul 12, 2023 at 12:58:54PM -0700, Kees Cook wrote: > On Tue, May 09, 2023 at 12:56:54PM -0400, Kent Overstreet wrote: > > From: Kent Overstreet <kent.overstreet@xxxxxxxxx> > > > > printbuf now needs to know the number of characters that would have been > > written if the buffer was too small, like snprintf(); this changes > > string_get_size() to return the the return value of snprintf(). > > Unfortunately, snprintf doesn't return characters written, it return > what it TRIED to write, and can cause a lot of problems[1]. This patch > would be fine with me if the snprintf was also replaced by scnprintf, > which will return the actual string length copied (or 0) *not* including > the trailing %NUL. Anyways, I can't use scnprintf here, printbufs/seq_buf both need the number of characters that would have been written, but I'll update the comment.
