This patch introduces the LOWPAN_IPHC_MAX_HC_BUF_LEN define which
represent the worst-case supported IPHC buffer length. It's used to
allocate the stack buffer space for creating the IPHC header.
Signed-off-by: Alexander Aring <alex.aring@xxxxxxxxx>
---
include/net/6lowpan.h | 8 ++++++++
net/6lowpan/iphc.c | 2 +-
2 files changed, 9 insertions(+), 1 deletion(-)
diff --git a/include/net/6lowpan.h b/include/net/6lowpan.h
index 07db532..aa5a823 100644
--- a/include/net/6lowpan.h
+++ b/include/net/6lowpan.h
@@ -64,12 +64,20 @@
#define EUI64_ADDR_LEN 8
#define LOWPAN_NHC_MAX_ID_LEN 1
+/* Maximum next header compression length which we currently support inclusive
+ * possible inline data.
+ */
+#define LOWPAN_NHC_MAX_HDR_LEN (sizeof(struct udphdr))
/* Max IPHC Header len without IPv6 hdr specific inline data.
* Useful for getting the "extra" bytes we need at worst case compression.
*
* LOWPAN_IPHC + CID + LOWPAN_NHC_MAX_ID_LEN
*/
#define LOWPAN_IPHC_MAX_HEADER_LEN (2 + 1 + LOWPAN_NHC_MAX_ID_LEN)
+/* Maximum worst case IPHC header buffer size */
+#define LOWPAN_IPHC_MAX_HC_BUF_LEN (sizeof(struct ipv6hdr) + \
+ LOWPAN_IPHC_MAX_HEADER_LEN + \
+ LOWPAN_NHC_MAX_HDR_LEN)
/*
* ipv6 address based on mac
diff --git a/net/6lowpan/iphc.c b/net/6lowpan/iphc.c
index 78c8a49..dd5f27d 100644
--- a/net/6lowpan/iphc.c
+++ b/net/6lowpan/iphc.c
@@ -429,7 +429,7 @@ int lowpan_header_compress(struct sk_buff *skb, struct net_device *dev,
{
u8 tmp, iphc0, iphc1, *hc_ptr;
struct ipv6hdr *hdr;
- u8 head[100] = {};
+ u8 head[LOWPAN_IPHC_MAX_HC_BUF_LEN] = {};
int ret, addr_type;
if (type != ETH_P_IPV6)
--
2.6.1
--
To unsubscribe from this list: send the line "unsubscribe linux-wpan" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
