[PATCH 2/2 net-next] thunderbolt: Right shifting to zero bug in tbnet_handle_packet()

Subsystems: networking drivers, the rest

STALE3247d

3 messages, 3 authors, 2017-10-19 · open the first message on its own page

[PATCH 2/2 net-next] thunderbolt: Right shifting to zero bug in tbnet_handle_packet()

From: Dan Carpenter <hidden>
Date: 2017-10-17 12:33:14

There is a problem when we do:

	sequence = pkg->hdr.length_sn & TBIP_HDR_SN_MASK;
	sequence >>= TBIP_HDR_SN_SHIFT;

TBIP_HDR_SN_SHIFT is 27, and right shifting a u8 27 bits is always
going to result in zero.  The fix is to declare these variables as u32.

Fixes: e69b6c02b4c3 ("net: Add support for networking over Thunderbolt cable")
Signed-off-by: Dan Carpenter <redacted>
diff --git a/drivers/net/thunderbolt.c b/drivers/net/thunderbolt.c
index 1a7bc0bf4598..435854688a7a 100644
--- a/drivers/net/thunderbolt.c
+++ b/drivers/net/thunderbolt.c
@@ -394,7 +394,7 @@ static int tbnet_handle_packet(const void *buf, size_t size, void *data)
 	struct tbnet *net = data;
 	u32 command_id;
 	int ret = 0;
-	u8 sequence;
+	u32 sequence;
 	u64 route;
 
 	/* Make sure the packet is for us */

Re: [PATCH 2/2 net-next] thunderbolt: Right shifting to zero bug in tbnet_handle_packet()

From: Bernat, Yehezkel <hidden>
Date: 2017-10-17 13:17:30

On Tue, 2017-10-17 at 15:33 +0300, Dan Carpenter wrote:
quoted hunk
There is a problem when we do:

	sequence = pkg->hdr.length_sn & TBIP_HDR_SN_MASK;
	sequence >>= TBIP_HDR_SN_SHIFT;

TBIP_HDR_SN_SHIFT is 27, and right shifting a u8 27 bits is always
going to result in zero.  The fix is to declare these variables as
u32.

Fixes: e69b6c02b4c3 ("net: Add support for networking over
Thunderbolt cable")
Signed-off-by: Dan Carpenter <redacted>
diff --git a/drivers/net/thunderbolt.c b/drivers/net/thunderbolt.c
index 1a7bc0bf4598..435854688a7a 100644
--- a/drivers/net/thunderbolt.c
+++ b/drivers/net/thunderbolt.c
@@ -394,7 +394,7 @@ static int tbnet_handle_packet(const void *buf,
size_t size, void *data)
 	struct tbnet *net = data;
 	u32 command_id;
 	int ret = 0;
-	u8 sequence;
+	u32 sequence;
 	u64 route;
 
 	/* Make sure the packet is for us */
Acked-by: Yehezkel Bernat <redacted>

Thanks!

Re: [PATCH 2/2 net-next] thunderbolt: Right shifting to zero bug in tbnet_handle_packet()

From: David Miller <davem@davemloft.net>
Date: 2017-10-19 12:05:20

From: Dan Carpenter <redacted>
Date: Tue, 17 Oct 2017 15:33:01 +0300
There is a problem when we do:

	sequence = pkg->hdr.length_sn & TBIP_HDR_SN_MASK;
	sequence >>= TBIP_HDR_SN_SHIFT;

TBIP_HDR_SN_SHIFT is 27, and right shifting a u8 27 bits is always
going to result in zero.  The fix is to declare these variables as u32.

Fixes: e69b6c02b4c3 ("net: Add support for networking over Thunderbolt cable")
Signed-off-by: Dan Carpenter <redacted>
Applied.
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help