FAILED: patch "[PATCH] mei: bus: type promotion bug in mei_nfc_if_version()" failed to apply to 4.14-stable tree

The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From: Dan Carpenter <[email protected]>
Date: Wed, 11 Jul 2018 15:29:31 +0300
Subject: [PATCH] mei: bus: type promotion bug in mei_nfc_if_version()

We accidentally removed the check for negative returns without considering the issue of type promotion.
The "if_version_length" variable is type size_t so if __mei_cl_recv() returns a negative then "bytes_recv" is type promoted
to a high positive value and treated as success.

index e45fe826d87d..65e28be3c8cc 100644
@@ -341,7 +341,7 @@ static int mei_nfc_if_version(struct mei_cl *cl,
 
 	ret = 0;
 	bytes_recv = __mei_cl_recv(cl, (u8 *)reply, if_version_length, 0, 0);
-	if (bytes_recv < if_version_length) {
+	if (bytes_recv < 0 || bytes_recv < if_version_length) {
 		dev_err(bus->dev, "Could not read IF version\n");
 		ret = -EIO;
 		goto err;

Hi Greg,

The attached backported patch should apply to 4.14-stable tree.

--
Regards
Sudip

From: Dan Carpenter <[email protected]>
Date: Wed, 11 Jul 2018 15:29:31 +0300
Subject: [PATCH] mei: bus: type promotion bug in mei_nfc_if_version()

commit b40b3e9358fbafff6a4ba0f4b9658f6617146f9c upstream

We accidentally removed the check for negative returns without considering the issue of type promotion.
The "if_version_length" variable is type size_t so if __mei_cl_recv() returns a negative then "bytes_recv" is type promoted
to a high positive value and treated as success.

---
 drivers/misc/mei/bus-fixup.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 0208c4b027c5..fa0236a5e59a 100644
@@ -267,7 +267,7 @@ static int mei_nfc_if_version(struct mei_cl *cl,
 
 	ret = 0;
 	bytes_recv = __mei_cl_recv(cl, (u8 *)reply, if_version_length, 0);
-	if (bytes_recv < if_version_length) {
+	if (bytes_recv < 0 || bytes_recv < if_version_length) {
 		dev_err(bus->dev, "Could not read IF version\n");
 		ret = -EIO;
 		goto err;

2.11.0