RE: [PATCH] perf cpumap: Use scnprintf instead of snprintf

[David Laight]

From: Christophe JAILLET
> Sent: 22 March 2020 17:25
> 'scnprintf' returns the number of characters written in the output buffer
> excluding the trailing '\0', instead of the number of characters which
> would be generated for the given input.
> 
> Both function return a number of characters, excluding the trailing '\0'.
> So comparaison to check if it overflows, should be done against max_size-1.
> Comparaison against max_size can never match.

NACK.
Since snprintf() returns the number of characters it would have
written to an infinite buffer the comparison can 'match'.

However it should test for (ret >= PATH_MAX).

	David

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