[34-longterm 021/209] irda: Fix heap memory corruption in iriap.c

[Paul Gortmaker]

From: Samuel Ortiz <samuel@xxxxxxxxxx>

  =====================================================================
  | This is a commit scheduled for the next v2.6.34 longterm release. |
  | If you see a problem with using this for longterm, please comment.|
  =====================================================================

commit 37f9fc452d138dfc4da2ee1ce5ae85094efc3606 upstream.

While parsing the GetValuebyClass command frame, we could potentially write
passed the skb->data pointer.

Reported-by: Ilja Van Sprundel <ivansprundel@xxxxxxxxxxxx>
Signed-off-by: Samuel Ortiz <samuel@xxxxxxxxxx>
Signed-off-by: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
---
 net/irda/iriap.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/net/irda/iriap.c b/net/irda/iriap.c
index 79a1e5a..b6fd6d1 100644
--- a/net/irda/iriap.c
+++ b/net/irda/iriap.c
@@ -502,7 +502,8 @@ static void iriap_getvaluebyclass_confirm(struct iriap_cb *self,
 		IRDA_DEBUG(4, "%s(), strlen=%d\n", __func__, value_len);
 
 		/* Make sure the string is null-terminated */
-		fp[n+value_len] = 0x00;
+		if (n + value_len < skb->len)
+			fp[n + value_len] = 0x00;
 		IRDA_DEBUG(4, "Got string %s\n", fp+n);
 
 		/* Will truncate to IAS_MAX_STRING bytes */
-- 
1.7.4.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/