[apparmor] [patch] Let the parser reject ambiguous unit 'm' for rlimit rttime

[Seth Arnold]

On Fri, May 22, 2015 at 01:39:40PM +0200, Christian Boltz wrote:
> === modified file 'parser/parser_yacc.y'
> --- parser/parser_yacc.y	2015-03-25 22:09:26 +0000
> +++ parser/parser_yacc.y	2015-05-22 00:07:48 +0000
> @@ -885,6 +885,8 @@
>  					yyerror("RLIMIT '%s' invalid value %s\n", $4, $6);
>  				if (*end == '\0') {
>  					value = tmp;
> +				} else if (*end == 'm\0') {

NAK, 'm\0' does not do what you want it to do. :)

'' delimits chars, and in a hilarious piece of history, enclosing
multiple chars in '' is perfectly legal in C, but -- and this is where it
gets extremely funny -- the result is implementation defined. GCC chooses
to let you build large numbers this way:

https://gcc.gnu.org/onlinedocs/cpp/Implementation-defined-behavior.html

In the end you're comparing a single character against the value 27904.

Probably strcmp("m",...) == 0 is the best approach here. There might be
something more clever.

> +					yyerror("RLIMIT '%s' ambiguous value %s - use either 'ms' or 'minutes'\n", $4, $6);

Minor point here, it'd be best to use "ambiguous unit" in this case.

Thanks
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