[PATCH 5.1 015/121] IB/hfi1: Validate fault injection opcode user input

[Greg Kroah-Hartman]

From: Kaike Wan <kaike....@intel.com>

commit 5f90677ed31963abb184ee08ebee4a4a68225dd8 upstream.

The opcode range for fault injection from user should be validated before
it is applied to the fault->opcodes[] bitmap to avoid out-of-bound
error.

Cc: <sta...@vger.kernel.org>
Fixes: a74d5307caba ("IB/hfi1: Rework fault injection machinery")
Reported-by: Dan Carpenter <dan.carpen...@oracle.com>
Reviewed-by: Mike Marciniszyn <mike.marcinis...@intel.com>
Signed-off-by: Kaike Wan <kaike....@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessan...@intel.com>
Signed-off-by: Jason Gunthorpe <j...@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 drivers/infiniband/hw/hfi1/fault.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/infiniband/hw/hfi1/fault.c
+++ b/drivers/infiniband/hw/hfi1/fault.c
@@ -153,6 +153,7 @@ static ssize_t fault_opcodes_write(struc
                char *dash;
                unsigned long range_start, range_end, i;
                bool remove = false;
+               unsigned long bound = 1U << BITS_PER_BYTE;
 
                end = strchr(ptr, ',');
                if (end)
@@ -178,6 +179,10 @@ static ssize_t fault_opcodes_write(struc
                                    BITS_PER_BYTE);
                        break;
                }
+               /* Check the inputs */
+               if (range_start >= bound || range_end >= bound)
+                       break;
+
                for (i = range_start; i <= range_end; i++) {
                        if (remove)
                                clear_bit(i, fault->opcodes);