4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Michael Mera <d...@michaelmera.com>
commit 062d0f22a30c39840ea49b72cfcfc1aa4cc538fa upstream.
In write to debugfs file 'resource_stats' the local buffer 'tmp_str' is
written at index 'count-1' where 'count' is the size of the write, so
potentially 0.
This patch filters odd values for the write size/position to avoid this
type of problem.
Signed-off-by: Michael Mera <d...@michaelmera.com>
Reviewed-by: Leon Romanovsky <leo...@mellanox.com>
Signed-off-by: Doug Ledford <dledf...@redhat.com>
Signed-off-by: Amit Pundir <amit.pun...@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
drivers/infiniband/hw/ocrdma/ocrdma_stats.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/infiniband/hw/ocrdma/ocrdma_stats.c
+++ b/drivers/infiniband/hw/ocrdma/ocrdma_stats.c
@@ -645,7 +645,7 @@ static ssize_t ocrdma_dbgfs_ops_write(st
struct ocrdma_stats *pstats = filp->private_data;
struct ocrdma_dev *dev = pstats->dev;
- if (count > 32)
+ if (*ppos != 0 || count == 0 || count > sizeof(tmp_str))
goto err;
if (copy_from_user(tmp_str, buffer, count))
