Re: [PATCH] lib/vsprintf.c: fix the incorrect return value ofvsnprintf()

[Al Viro]

On Thu, Jul 18, 2013 at 02:28:49PM +0800, Chen Gang wrote:
> When "str >= end", necessary to reset 'str' to "end - 1", or the return
> value will be larger than the real one, the callers which depend on the
> return value, may cause memory overflow.

You do realize that snprintf(s, 1, "abc") should return 3, not 1?  The
goal off snprintf() is _not_ just to truncate the output; return value
tells how much should the buffer had been to fit the whole thing.
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