scsi: isci: Fix infinite loop in while loop

[ Upstream commit 4bc83b3f ]

In the case when the phy_mask is bitwise anded with the phy_index bit is
zero the continue statement currently jumps to the next iteration of the
while loop and phy_index is never actually incremented, potentially
causing an infinite loop if phy_index is less than SCI_MAX_PHS. Fix this
by turning the while loop into a for loop.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/scsi/isci/port_config.c

@@ -291,7 +291,7 @@ sci_mpc_agent_validate_phy_configuration(struct isci_host *ihost,
 		 * Note: We have not moved the current phy_index so we will actually
 		 *       compare the startting phy with itself.
 		 *       This is expected and required to add the phy to the port. */
-		while (phy_index < SCI_MAX_PHYS) {
+		for (; phy_index < SCI_MAX_PHYS; phy_index++) {
 			if ((phy_mask & (1 << phy_index)) == 0)
 				continue;
 			sci_phy_get_sas_address(&ihost->phys[phy_index],
@@ -311,7 +311,6 @@ sci_mpc_agent_validate_phy_configuration(struct isci_host *ihost,
 					      &ihost->phys[phy_index]);
 
 			assigned_phy_mask |= (1 << phy_index);
-			phy_index++;
 		}
 
 	}