Re: [PATCH v2] bcachefs: Avoid a potential useless over memory allocation in bch2_prt_[v]printf()

[Kent Overstreet]

On Sun, Feb 18, 2024 at 05:12:28PM +0100, Christophe JAILLET wrote:
> 2 issues related to incorrect available space in the output buffer
> computation may lead to some extra memory allocation.
> 
> 
> First: vsnprintf() takes the size of the buffer, *including* the space for
> the trailing null.
> 
> But printbuf_remaining() returns the number of characters we can print
> to the output buffer, *excluding* the terminating null.
> 
> So, use printbuf_remaining_size(), which includes the space for the
> terminating null.
> 
> 
> Second: if the return value of vsnprintf() is greater than or equal to the
> passed size, the resulting string is truncated.
> So, in order to see if some extra space is needed, the check needs to be
> changed.
> 
> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>

Thanks, applied