i3c: Fix a shift wrap bug in i3c_bus_set_addr_slot_status()

commit 476c7e1d34f2a03b1aa5a924c50703053fe5f77c upstream.

The problem here is that addr can be I3C_BROADCAST_ADDR (126).  That
means we're shifting by (126 * 2) % 64 which is 60.  The
I3C_ADDR_SLOT_STATUS_MASK is an enum which is an unsigned int in GCC
so shifts greater than 31 are undefined.

Fixes: 3a379bbcea0a ("i3c: Add core I3C infrastructure")
Cc: <stable@vger.kernel.org>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
index 1412abcff01095cd001ece69bb80a69d714a80ba..5f4bd52121fe93c5843767ce4614a97965cddd2d 100644 (file)
--- a/drivers/i3c/master.c
+++ b/drivers/i3c/master.c
@@ -385,8 +385,9 @@ static void i3c_bus_set_addr_slot_status(struct i3c_bus *bus, u16 addr,
                return;
 
        ptr = bus->addrslots + (bitpos / BITS_PER_LONG);
-       *ptr &= ~(I3C_ADDR_SLOT_STATUS_MASK << (bitpos % BITS_PER_LONG));
-       *ptr |= status << (bitpos % BITS_PER_LONG);
+       *ptr &= ~((unsigned long)I3C_ADDR_SLOT_STATUS_MASK <<
+                                               (bitpos % BITS_PER_LONG));
+       *ptr |= (unsigned long)status << (bitpos % BITS_PER_LONG);
 }
 
 static bool i3c_bus_dev_addr_is_avail(struct i3c_bus *bus, u8 addr)