Previously values greater than 255 were implicitly truncated. Add some stricter checking to reject addresses with components >255.
With the input "1234192.168.1.1" the old behaviour would truncate the address to 192.168.1.1. New behaviour rejects the string outright and returns 0.0.0.0, which for the purposes of IP addresses can be considered an error.
Signed-off-by: Chris Packham judge.packham@gmail.com ---
lib/net_utils.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/lib/net_utils.c b/lib/net_utils.c index cfae842..0fca54d 100644 --- a/lib/net_utils.c +++ b/lib/net_utils.c @@ -24,10 +24,19 @@ struct in_addr string_to_ip(const char *s)
for (addr.s_addr = 0, i = 0; i < 4; ++i) { ulong val = s ? simple_strtoul(s, &e, 10) : 0; + if (val > 255) { + addr.s_addr = 0; + return addr; + } addr.s_addr <<= 8; addr.s_addr |= (val & 0xFF); - if (s) { - s = (*e) ? e+1 : e; + if (*e == '.') { + s = e + 1; + } else if (*e == '\0') { + break; + } else { + addr.s_addr = 0; + return addr; } }