[PATCH net-next 3/9] e100: replace deprecated strncpy with strscpy

[PATCH net-next 3/9] e100: replace deprecated strncpy with strscpy

[Jacob Keller]

From: Justin Stitt <justinstitt@google.com>

`strncpy` is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.

The "...-1" pattern makes it evident that netdev->name is expected to be
NUL-terminated.

Meanwhile, it seems NUL-padding is not required due to alloc_etherdev
zero-allocating the buffer.

Considering the above, a suitable replacement is `strscpy` [2] due to
the fact that it guarantees NUL-termination on the destination buffer
without unnecessarily NUL-padding.

This is in line with other uses of strscpy on netdev->name:
$ rg "strscpy\(netdev\->name.*pci.*"

drivers/net/ethernet/intel/e1000e/netdev.c
7455:   strscpy(netdev->name, pci_name(pdev), sizeof(netdev->name));

drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
10839:  strscpy(netdev->name, pci_name(pdev), sizeof(netdev->name));

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
---
 drivers/net/ethernet/intel/e100.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/e100.c b/drivers/net/ethernet/intel/e100.c
index d3fdc290937f..01f0f12035ca 100644
--- a/drivers/net/ethernet/intel/e100.c
+++ b/drivers/net/ethernet/intel/e100.c
@@ -2841,7 +2841,7 @@ static int e100_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	netdev->netdev_ops = &e100_netdev_ops;
 	netdev->ethtool_ops = &e100_ethtool_ops;
 	netdev->watchdog_timeo = E100_WATCHDOG_PERIOD;
-	strncpy(netdev->name, pci_name(pdev), sizeof(netdev->name) - 1);
+	strscpy(netdev->name, pci_name(pdev), sizeof(netdev->name));
 
 	nic = netdev_priv(netdev);
 	netif_napi_add_weight(netdev, &nic->napi, e100_poll, E100_NAPI_WEIGHT);
-- 
2.41.0

[PATCH net-next 4/9] e1000: replace deprecated strncpy with strscpy

[Jacob Keller]

From: Justin Stitt <justinstitt@google.com>

`strncpy` is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.

We can see that netdev->name is expected to be NUL-terminated based on
it's usage with format strings:
|       pr_info("%s NIC Link is Down\n",
|               netdev->name);

A suitable replacement is `strscpy` [2] due to the fact that it
guarantees NUL-termination on the destination buffer without
unnecessarily NUL-padding.

This is in line with other uses of strscpy on netdev->name:
$ rg "strscpy\(netdev\->name.*pci.*"

drivers/net/ethernet/intel/e1000e/netdev.c
7455:   strscpy(netdev->name, pci_name(pdev), sizeof(netdev->name));

drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
10839:  strscpy(netdev->name, pci_name(pdev), sizeof(netdev->name));

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
---
 drivers/net/ethernet/intel/e1000/e1000_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/e1000/e1000_main.c b/drivers/net/ethernet/intel/e1000/e1000_main.c
index da6e303ad99b..1d1e93686af2 100644
--- a/drivers/net/ethernet/intel/e1000/e1000_main.c
+++ b/drivers/net/ethernet/intel/e1000/e1000_main.c
@@ -1014,7 +1014,7 @@ static int e1000_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	netdev->watchdog_timeo = 5 * HZ;
 	netif_napi_add(netdev, &adapter->napi, e1000_clean);
 
-	strncpy(netdev->name, pci_name(pdev), sizeof(netdev->name) - 1);
+	strscpy(netdev->name, pci_name(pdev), sizeof(netdev->name));
 
 	adapter->bd_number = cards_found;
 
-- 
2.41.0

[PATCH net-next 5/9] fm10k: replace deprecated strncpy with strscpy

[Jacob Keller]

From: Justin Stitt <justinstitt@google.com>

`strncpy` is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.

A suitable replacement is `strscpy` [2] due to the fact that it
guarantees NUL-termination on the destination buffer without
unnecessarily NUL-padding.

Other implementations of .*get_drvinfo also use strscpy so this patch
brings fm10k_get_drvinfo in line as well:

igb/igb_ethtool.c +851
static void igb_get_drvinfo(struct net_device *netdev,

igbvf/ethtool.c
167:static void igbvf_get_drvinfo(struct net_device *netdev,

i40e/i40e_ethtool.c
1999:static void i40e_get_drvinfo(struct net_device *netdev,

e1000/e1000_ethtool.c
529:static void e1000_get_drvinfo(struct net_device *netdev,

ixgbevf/ethtool.c
211:static void ixgbevf_get_drvinfo(struct net_device *netdev,

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
---
 drivers/net/ethernet/intel/fm10k/fm10k_ethtool.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_ethtool.c b/drivers/net/ethernet/intel/fm10k/fm10k_ethtool.c
index d53369e30040..13a05604dcc0 100644
--- a/drivers/net/ethernet/intel/fm10k/fm10k_ethtool.c
+++ b/drivers/net/ethernet/intel/fm10k/fm10k_ethtool.c
@@ -448,10 +448,10 @@ static void fm10k_get_drvinfo(struct net_device *dev,
 {
 	struct fm10k_intfc *interface = netdev_priv(dev);
 
-	strncpy(info->driver, fm10k_driver_name,
-		sizeof(info->driver) - 1);
-	strncpy(info->bus_info, pci_name(interface->pdev),
-		sizeof(info->bus_info) - 1);
+	strscpy(info->driver, fm10k_driver_name,
+		sizeof(info->driver));
+	strscpy(info->bus_info, pci_name(interface->pdev),
+		sizeof(info->bus_info));
 }
 
 static void fm10k_get_pauseparam(struct net_device *dev,
-- 
2.41.0

[PATCH net-next 6/9] i40e: use scnprintf over strncpy+strncat

[Jacob Keller]

From: Justin Stitt <justinstitt@google.com>

`strncpy` is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.

Moreover, `strncat` shouldn't really be used either as per
fortify-string.h:
 * Do not use this function. While FORTIFY_SOURCE tries to avoid
 * read and write overflows, this is only possible when the sizes
 * of @p and @q are known to the compiler. Prefer building the
 * string with formatting, via scnprintf() or similar.

Instead, use `scnprintf` with "%s%s" format string. This code is now
more readable and robust.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
---
 drivers/net/ethernet/intel/i40e/i40e_ddp.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_ddp.c b/drivers/net/ethernet/intel/i40e/i40e_ddp.c
index 6b68b6575a1d..cf25bfc5dc3f 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_ddp.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_ddp.c
@@ -456,10 +456,9 @@ int i40e_ddp_flash(struct net_device *netdev, struct ethtool_flash *flash)
 		char profile_name[sizeof(I40E_DDP_PROFILE_PATH)
 				  + I40E_DDP_PROFILE_NAME_MAX];
 
-		profile_name[sizeof(profile_name) - 1] = 0;
-		strncpy(profile_name, I40E_DDP_PROFILE_PATH,
-			sizeof(profile_name) - 1);
-		strncat(profile_name, flash->data, I40E_DDP_PROFILE_NAME_MAX);
+		scnprintf(profile_name, sizeof(profile_name), "%s%s",
+			  I40E_DDP_PROFILE_PATH, flash->data);
+
 		/* Load DDP recipe. */
 		status = request_firmware(&ddp_config, profile_name,
 					  &netdev->dev);
-- 
2.41.0

[PATCH net-next 7/9] igb: replace deprecated strncpy with strscpy

[Jacob Keller]

From: Justin Stitt <justinstitt@google.com>

`strncpy` is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.

We see that netdev->name is expected to be NUL-terminated based on its
usage with format strings:
|       sprintf(q_vector->name, "%s-TxRx-%u", netdev->name,
|               q_vector->rx.ring->queue_index);

Furthermore, NUL-padding is not required as netdev is already
zero-allocated:
|       netdev = alloc_etherdev_mq(sizeof(struct igb_adapter),
|                                  IGB_MAX_TX_QUEUES);
...
alloc_etherdev_mq() -> alloc_etherdev_mqs() -> alloc_netdev_mqs() ...
|       p = kvzalloc(alloc_size, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL);

Considering the above, a suitable replacement is `strscpy` [2] due to
the fact that it guarantees NUL-termination on the destination buffer
without unnecessarily NUL-padding.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
---
 drivers/net/ethernet/intel/igb/igb_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
index fdadf3e84f59..db54453e1946 100644
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -3263,7 +3263,7 @@ static int igb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	igb_set_ethtool_ops(netdev);
 	netdev->watchdog_timeo = 5 * HZ;
 
-	strncpy(netdev->name, pci_name(pdev), sizeof(netdev->name) - 1);
+	strscpy(netdev->name, pci_name(pdev), sizeof(netdev->name));
 
 	netdev->mem_start = pci_resource_start(pdev, 0);
 	netdev->mem_end = pci_resource_end(pdev, 0);
-- 
2.41.0

[PATCH net-next 8/9] igbvf: replace deprecated strncpy with strscpy

[Jacob Keller]

From: Justin Stitt <justinstitt@google.com>

`strncpy` is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.

We expect netdev->name to be NUL-terminated based on its usage with
`strlen` and format strings:
|       if (strlen(netdev->name) < (IFNAMSIZ - 5)) {
|               sprintf(adapter->tx_ring->name, "%s-tx-0", netdev->name);

Moreover, we do not need NUL-padding as netdev is already
zero-allocated:
|       netdev = alloc_etherdev(sizeof(struct igbvf_adapter));
...
alloc_etherdev() -> alloc_etherdev_mq() -> alloc_etherdev_mqs() ->
alloc_netdev_mqs() ...
|       p = kvzalloc(alloc_size, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL);

Considering the above, a suitable replacement is `strscpy` [2] due to
the fact that it guarantees NUL-termination on the destination buffer
without unnecessarily NUL-padding.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
---
 drivers/net/ethernet/intel/igbvf/netdev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/igbvf/netdev.c b/drivers/net/ethernet/intel/igbvf/netdev.c
index 7ff2752dd763..fd712585af27 100644
--- a/drivers/net/ethernet/intel/igbvf/netdev.c
+++ b/drivers/net/ethernet/intel/igbvf/netdev.c
@@ -2785,7 +2785,7 @@ static int igbvf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	igbvf_set_ethtool_ops(netdev);
 	netdev->watchdog_timeo = 5 * HZ;
-	strncpy(netdev->name, pci_name(pdev), sizeof(netdev->name) - 1);
+	strscpy(netdev->name, pci_name(pdev), sizeof(netdev->name));
 
 	adapter->bd_number = cards_found++;
 
-- 
2.41.0

[PATCH net-next 9/9] igc: replace deprecated strncpy with strscpy

[Jacob Keller]

From: Justin Stitt <justinstitt@google.com>

`strncpy` is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.

We expect netdev->name to be NUL-terminated based on its use with format
strings:
|       if (q_vector->rx.ring && q_vector->tx.ring)
|               sprintf(q_vector->name, "%s-TxRx-%u", netdev->name,

Furthermore, we do not need NUL-padding as netdev is already
zero-allocated:
|       netdev = alloc_etherdev_mq(sizeof(struct igc_adapter),
|                                  IGC_MAX_TX_QUEUES);
...
alloc_etherdev() -> alloc_etherdev_mq() -> alloc_etherdev_mqs() ->
alloc_netdev_mqs() ...
|       p = kvzalloc(alloc_size, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL);

Considering the above, a suitable replacement is `strscpy` [2] due to
the fact that it guarantees NUL-termination on the destination buffer
without unnecessarily NUL-padding.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
---
 drivers/net/ethernet/intel/igc/igc_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 98de34d0ce07..e9bb403bbacf 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -6935,7 +6935,7 @@ static int igc_probe(struct pci_dev *pdev,
 	 */
 	igc_get_hw_control(adapter);
 
-	strncpy(netdev->name, "eth%d", IFNAMSIZ);
+	strscpy(netdev->name, "eth%d", sizeof(netdev->name));
 	err = register_netdev(netdev);
 	if (err)
 		goto err_register;
-- 
2.41.0