devargs: fix parsing truncation when using format

Space for string terminating NUL character should be provided to
snprintf() to avoid the last symbol truncation.

Fixes: a23bc2c4e01b ("devargs: add non-variadic parsing function")

Reported-by: Ivan Malov <ivan.malov@oktetlabs.ru>
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
Acked-by: Gaetan Rivet <gaetan.rivet@6wind.com>

diff --git a/lib/librte_eal/common/eal_common_devargs.c b/lib/librte_eal/common/eal_common_devargs.c
index 1a7b00e..dac2402 100644 (file)
--- a/lib/librte_eal/common/eal_common_devargs.c
+++ b/lib/librte_eal/common/eal_common_devargs.c
@@ -285,7 +285,7 @@ rte_devargs_parsef(struct rte_devargs *da, const char *format, ...)
        }
 
        va_start(ap, format);
-       vsnprintf(dev, len, format, ap);
+       vsnprintf(dev, len + 1, format, ap);
        va_end(ap);
 
        return rte_devargs_parse(da, dev);