From dc23c2d7afd2103cbc589372769c2f6723ea5235 Mon Sep 17 00:00:00 2001 From: Jan Engelhardt Date: Fri, 13 Jul 2012 23:18:29 +0200 Subject: libxt_u32: do bounds checking for @'s operands Using only strtoul is prone to accept all values, including negative ones which are not explicitly allowed. Therefore, use xtables_strtoui with bounds checking. Signed-off-by: Jan Engelhardt --- extensions/libxt_u32.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) (limited to 'extensions/libxt_u32.c') diff --git a/extensions/libxt_u32.c b/extensions/libxt_u32.c index 6d024fb6..2a7f5d80 100644 --- a/extensions/libxt_u32.c +++ b/extensions/libxt_u32.c @@ -88,17 +88,13 @@ static void u32_dump(const struct xt_u32 *data) /* string_to_number() is not quite what we need here ... */ static uint32_t parse_number(const char **s, int pos) { - uint32_t number; + unsigned int number; char *end; - errno = 0; - number = strtoul(*s, &end, 0); - if (end == *s) + if (!xtables_strtoui(*s, &end, &number, 0, UINT32_MAX) || + end == *s) xtables_error(PARAMETER_PROBLEM, - "u32: at char %d: expected number", pos); - if (errno != 0) - xtables_error(PARAMETER_PROBLEM, - "u32: at char %d: error reading number", pos); + "u32: at char %d: not a number or out of range", pos); *s = end; return number; } -- cgit v1.2.3