ixgbe: eliminate Smatch warnings in ixgbe_debugfs.c
This patch replaces calls to copy_to_user, copy_from_user, and the associated
logic, with calls to simple_read_from_buffer and simple_write_to_buffer
respectively. This was done to eliminate warnings generated by the Smatch
static analysis tool.
v2- Fix return values based community feedback
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
CC: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Josh Hay <joshua.a.hay@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c
index efaf9a7..50aa546 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_debugfs.c
@@ -47,23 +47,27 @@
size_t count, loff_t *ppos)
{
struct ixgbe_adapter *adapter = filp->private_data;
- char buf[256];
- int bytes_not_copied;
+ char *buf;
int len;
/* don't allow partial reads */
if (*ppos != 0)
return 0;
- len = snprintf(buf, sizeof(buf), "%s: %s\n",
- adapter->netdev->name, ixgbe_dbg_reg_ops_buf);
- if (count < len)
- return -ENOSPC;
- bytes_not_copied = copy_to_user(buffer, buf, len);
- if (bytes_not_copied < 0)
- return bytes_not_copied;
+ buf = kasprintf(GFP_KERNEL, "%s: %s\n",
+ adapter->netdev->name,
+ ixgbe_dbg_reg_ops_buf);
+ if (!buf)
+ return -ENOMEM;
- *ppos = len;
+ if (count < strlen(buf)) {
+ kfree(buf);
+ return -ENOSPC;
+ }
+
+ len = simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf));
+
+ kfree(buf);
return len;
}
@@ -79,7 +83,7 @@
size_t count, loff_t *ppos)
{
struct ixgbe_adapter *adapter = filp->private_data;
- int bytes_not_copied;
+ int len;
/* don't allow partial writes */
if (*ppos != 0)
@@ -87,14 +91,15 @@
if (count >= sizeof(ixgbe_dbg_reg_ops_buf))
return -ENOSPC;
- bytes_not_copied = copy_from_user(ixgbe_dbg_reg_ops_buf, buffer, count);
- if (bytes_not_copied < 0)
- return bytes_not_copied;
- else if (bytes_not_copied < count)
- count -= bytes_not_copied;
- else
- return -ENOSPC;
- ixgbe_dbg_reg_ops_buf[count] = '\0';
+ len = simple_write_to_buffer(ixgbe_dbg_reg_ops_buf,
+ sizeof(ixgbe_dbg_reg_ops_buf)-1,
+ ppos,
+ buffer,
+ count);
+ if (len < 0)
+ return len;
+
+ ixgbe_dbg_reg_ops_buf[len] = '\0';
if (strncmp(ixgbe_dbg_reg_ops_buf, "write", 5) == 0) {
u32 reg, value;
@@ -147,23 +152,27 @@
size_t count, loff_t *ppos)
{
struct ixgbe_adapter *adapter = filp->private_data;
- char buf[256];
- int bytes_not_copied;
+ char *buf;
int len;
/* don't allow partial reads */
if (*ppos != 0)
return 0;
- len = snprintf(buf, sizeof(buf), "%s: %s\n",
- adapter->netdev->name, ixgbe_dbg_netdev_ops_buf);
- if (count < len)
- return -ENOSPC;
- bytes_not_copied = copy_to_user(buffer, buf, len);
- if (bytes_not_copied < 0)
- return bytes_not_copied;
+ buf = kasprintf(GFP_KERNEL, "%s: %s\n",
+ adapter->netdev->name,
+ ixgbe_dbg_netdev_ops_buf);
+ if (!buf)
+ return -ENOMEM;
- *ppos = len;
+ if (count < strlen(buf)) {
+ kfree(buf);
+ return -ENOSPC;
+ }
+
+ len = simple_read_from_buffer(buffer, count, ppos, buf, strlen(buf));
+
+ kfree(buf);
return len;
}
@@ -179,7 +188,7 @@
size_t count, loff_t *ppos)
{
struct ixgbe_adapter *adapter = filp->private_data;
- int bytes_not_copied;
+ int len;
/* don't allow partial writes */
if (*ppos != 0)
@@ -187,15 +196,15 @@
if (count >= sizeof(ixgbe_dbg_netdev_ops_buf))
return -ENOSPC;
- bytes_not_copied = copy_from_user(ixgbe_dbg_netdev_ops_buf,
- buffer, count);
- if (bytes_not_copied < 0)
- return bytes_not_copied;
- else if (bytes_not_copied < count)
- count -= bytes_not_copied;
- else
- return -ENOSPC;
- ixgbe_dbg_netdev_ops_buf[count] = '\0';
+ len = simple_write_to_buffer(ixgbe_dbg_netdev_ops_buf,
+ sizeof(ixgbe_dbg_netdev_ops_buf)-1,
+ ppos,
+ buffer,
+ count);
+ if (len < 0)
+ return len;
+
+ ixgbe_dbg_netdev_ops_buf[len] = '\0';
if (strncmp(ixgbe_dbg_netdev_ops_buf, "tx_timeout", 10) == 0) {
adapter->netdev->netdev_ops->ndo_tx_timeout(adapter->netdev);