An off-by-one error in resolv_found() could make an strncat() call
overflow by the terminating null byte.
When building with Clang the following warning was shown:
../../../core/net/ip/resolv.c:1458:17: warning: the value of the
size argument in 'strncat' is too large, might lead to a
buffer overflow [-Wstrncat-size]
sizeof(resolv_hostname) - strlen(resolv_hostname));
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../../../core/net/ip/resolv.c:1458:17: note: change the argument to
be the free space in the destination buffer minus the
terminating null byte
sizeof(resolv_hostname) - strlen(resolv_hostname));
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sizeof(resolv_hostname) - strlen(resolv_hostname) - 1
Signed-off-by: Joakim Gebart <joakim.gebart@eistec.se>
