diff options
| -rw-r--r-- | net/checksum.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/net/checksum.c b/net/checksum.c index 14c08550e0..0942437c05 100644 --- a/net/checksum.c +++ b/net/checksum.c @@ -59,6 +59,11 @@ void net_checksum_calculate(uint8_t *data, int length) int hlen, plen, proto, csum_offset; uint16_t csum; + /* Ensure data has complete L2 & L3 headers. */ + if (length < 14 + 20) { + return; + } + if ((data[14] & 0xf0) != 0x40) return; /* not IPv4 */ hlen = (data[14] & 0x0f) * 4; @@ -76,8 +81,9 @@ void net_checksum_calculate(uint8_t *data, int length) return; } - if (plen < csum_offset+2) - return; + if (plen < csum_offset + 2 || 14 + hlen + plen > length) { + return; + } data[14+hlen+csum_offset] = 0; data[14+hlen+csum_offset+1] = 0; |