On 2023-01-17, Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> wrote: > On (23/01/16 17:35), Petr Mladek wrote: >> len = snprintf(scratchbuf, scratchbuf_sz, >> "** %lu printk messages dropped **\n", dropped); > > Wouldn't > > if (WARN_ON_ONCE(len + PRINTK_PREFIX_MAX >= outbuf_sz)) > return; > > prevent us from doing something harmful? Sure. But @0len is supposed to contain the number of bytes in @scratchbuf, which theoretically it does not. snprintf() is the wrong function to use here, even if there is not real danger in this situation. John Ogness
