From mboxrd@z Thu Jan 1 00:00:00 1970 From: Geert Uytterhoeven Subject: Re: [PATCH] of: do not leak console options Date: Fri, 13 Oct 2017 21:48:34 +0200 Message-ID: References: <20170926062510.4948-1-sergey.senozhatsky@gmail.com> <20171003072007.GB9706@pathway.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: <20171003072007.GB9706-KsEp0d+Q8qECVLCxKZUutA@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Petr Mladek Cc: Sergey Senozhatsky , Rob Herring , Steven Rostedt , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Sergey Senozhatsky List-Id: devicetree@vger.kernel.org On Tue, Oct 3, 2017 at 9:20 AM, Petr Mladek wrote: > On Tue 2017-09-26 15:25:10, Sergey Senozhatsky wrote: >> Do not strdup() console options. It seems that the only reason for >> it to be strdup()-ed was a compilation warning: printk, UART and >> console drivers, for some reason, expect char pointer instead of >> const char pointer. So we can just pass `of_stdout_options', but >> need to cast it to char pointer. A better fix would be to change >> printk, console drivers and UART to accept const char `options'; >> but that will take time - there are lots of drivers to update. >> >> The patch also fixes a possible memory leak: add_preferred_console() >> can fail, but we don't kfree() options. >> >> Signed-off-by: Sergey Senozhatsky > > Of course, it would be better to change add_preferred_console(). > But it would trigger many other changes. This alternative > "temporary" change looks safe to me. Feel free to use Really? Unless I'm missing something (it's been way too many hours after my morning coffee), add_preferred_console() just calls __add_preferred_console(), and the latter doesn't touch the passed string. As passing a "char *" to a function that excepts a "const char *" is fine, you can just add "const" to both add_preferred_console() and __add_preferred_console(), and be done with it. Repeat after me: casts are evil. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html