[PATCH][V2] isci: Fix infinite loop in while loop

[PATCH][V2] isci: Fix infinite loop in while loop

[Colin King]

From: Colin Ian King <colin.king@canonical.com>

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>
---
 drivers/scsi/isci/port_config.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/scsi/isci/port_config.c b/drivers/scsi/isci/port_config.c
index edb7be786c65..9e8de1462593 100644
--- a/drivers/scsi/isci/port_config.c
+++ b/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++;
 		}
 
 	}
-- 
2.17.0

Re: [PATCH][V2] isci: Fix infinite loop in while loop

[Martin K. Petersen]

Colin,

> 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.

Applied to 4.17/scsi-fixes. Thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering