The patch below does not apply to the 4.18-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 stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From b40b3e9358fbafff6a4ba0f4b9658f6617146f9c Mon Sep 17 00:00:00 2001
From: Dan Carpenter dan.carpenter@oracle.com 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.
Cc: stable@vger.kernel.org Fixes: 582ab27a063a ("mei: bus: fix received data size check in NFC fixup") Signed-off-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Tomas Winkler tomas.winkler@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
diff --git a/drivers/misc/mei/bus-fixup.c b/drivers/misc/mei/bus-fixup.c index e45fe826d87d..65e28be3c8cc 100644 --- a/drivers/misc/mei/bus-fixup.c +++ b/drivers/misc/mei/bus-fixup.c @@ -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;