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Diffstat (limited to 'net')
-rw-r--r--net/checksum.c10
1 files changed, 8 insertions, 2 deletions
diff --git a/net/checksum.c b/net/checksum.c
index b5016ab40c..d0fa424cc1 100644
--- a/net/checksum.c
+++ b/net/checksum.c
@@ -60,6 +60,11 @@ 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;
@@ -77,8 +82,9 @@ 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;