diff options
Diffstat (limited to 'src/net/dhcpopts.c')
| -rw-r--r-- | src/net/dhcpopts.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/src/net/dhcpopts.c b/src/net/dhcpopts.c index 64b310d4e..1898011aa 100644 --- a/src/net/dhcpopts.c +++ b/src/net/dhcpopts.c @@ -118,6 +118,11 @@ static int find_dhcp_option_with_encap ( struct dhcp_options *options, ssize_t remaining = options->len; unsigned int option_len; + /* Sanity check */ + if ( tag == DHCP_PAD ) + return -ENOENT; + + /* Search for option */ while ( remaining ) { /* Calculate length of this option. Abort processing * if the length is malformed (i.e. takes us beyond @@ -128,6 +133,9 @@ static int find_dhcp_option_with_encap ( struct dhcp_options *options, remaining -= option_len; if ( remaining < 0 ) break; + /* Check for explicit end marker */ + if ( option->tag == DHCP_END ) + break; /* Check for matching tag */ if ( option->tag == tag ) { DBGC ( options, "DHCPOPT %p found %s (length %d)\n", @@ -135,9 +143,6 @@ static int find_dhcp_option_with_encap ( struct dhcp_options *options, option_len ); return offset; } - /* Check for explicit end marker */ - if ( option->tag == DHCP_END ) - break; /* Check for start of matching encapsulation block */ if ( DHCP_IS_ENCAP_OPT ( tag ) && ( option->tag == DHCP_ENCAPSULATOR ( tag ) ) ) { @@ -151,6 +156,7 @@ static int find_dhcp_option_with_encap ( struct dhcp_options *options, } offset += option_len; } + return -ENOENT; } @@ -255,6 +261,10 @@ static int set_dhcp_option ( struct dhcp_options *options, unsigned int tag, size_t new_len = ( len ? ( len + DHCP_OPTION_HEADER_LEN ) : 0 ); int rc; + /* Sanity check */ + if ( tag == DHCP_PAD ) + return -ENOTTY; + /* Find old instance of this option, if any */ offset = find_dhcp_option_with_encap ( options, tag, &encap_offset ); if ( offset >= 0 ) { |