[PATCH 4.19 143/243] net/x25: fix called/calling length calculation in x25_parse_address_block

From: Greg Kroah-Hartman
Date: Wed Dec 11 2019 - 10:22:20 EST


From: Martin Schiller <ms@xxxxxxxxxx>

[ Upstream commit d449ba3d581ed29f751a59792fdc775572c66904 ]

The length of the called and calling address was not calculated
correctly (BCD encoding).

Signed-off-by: Martin Schiller <ms@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/x25/af_x25.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c
index f7f53f9ae7efb..3150648206b68 100644
--- a/net/x25/af_x25.c
+++ b/net/x25/af_x25.c
@@ -100,7 +100,7 @@ int x25_parse_address_block(struct sk_buff *skb,
}

len = *skb->data;
- needed = 1 + (len >> 4) + (len & 0x0f);
+ needed = 1 + ((len >> 4) + (len & 0x0f) + 1) / 2;

if (!pskb_may_pull(skb, needed)) {
/* packet is too short to hold the addresses it claims
--
2.20.1