diff mbox series

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

Message ID 20231017190411.2199743-8-jacob.e.keller@intel.com (mailing list archive)
State Accepted
Commit 95e71e35e63561b5c5a5510dc7e429d95ad1dd3b
Delegated to: Netdev Maintainers
Headers show
Series Intel Wired LAN Driver Updates 2023-10-17 | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1363 this patch: 1363
netdev/cc_maintainers warning 5 maintainers not CCed: intel-wired-lan@lists.osuosl.org pabeni@redhat.com edumazet@google.com jesse.brandeburg@intel.com anthony.l.nguyen@intel.com
netdev/build_clang success Errors and warnings before: 1388 this patch: 1388
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1388 this patch: 1388
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 8 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Jacob Keller Oct. 17, 2023, 7:04 p.m. UTC 
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 mbox series

Patch

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);