| Message ID | 20231011-strncpy-drivers-net-ethernet-mellanox-mlx4-fw-c-v1-1-4d7b5d34c933@google.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | net/mlx4_core: replace deprecated strncpy with strscpy | expand |
On Wed, Oct 11, 2023 at 09:04:37PM +0000, Justin Stitt wrote: > `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 `dst` to be NUL-terminated based on its use with format > strings: > | mlx4_dbg(dev, "Reporting Driver Version to FW: %s\n", dst); > > Moreover, NUL-padding is not required. Yup, since it's only use is for the above report. > > 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> Thanks! Reviewed-by: Kees Cook <keescook@chromium.org>
On 11 Oct 21:04, Justin Stitt wrote: >`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 `dst` to be NUL-terminated based on its use with format >strings: >| mlx4_dbg(dev, "Reporting Driver Version to FW: %s\n", dst); > >Moreover, NUL-padding is not required. > >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> >--- >Note: build-tested only. > >Found with: $ rg "strncpy\(" >--- > drivers/net/ethernet/mellanox/mlx4/fw.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > >diff --git a/drivers/net/ethernet/mellanox/mlx4/fw.c b/drivers/net/ethernet/mellanox/mlx4/fw.c >index fe48d20d6118..0005d9e2c2d6 100644 >--- a/drivers/net/ethernet/mellanox/mlx4/fw.c >+++ b/drivers/net/ethernet/mellanox/mlx4/fw.c >@@ -1967,7 +1967,7 @@ int mlx4_INIT_HCA(struct mlx4_dev *dev, struct mlx4_init_hca_param *param) > if (dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_DRIVER_VERSION_TO_FW) { > u8 *dst = (u8 *)(inbox + INIT_HCA_DRIVER_VERSION_OFFSET / 4); > >- strncpy(dst, DRV_NAME_FOR_FW, INIT_HCA_DRIVER_VERSION_SZ - 1); >+ strscpy(dst, DRV_NAME_FOR_FW, INIT_HCA_DRIVER_VERSION_SZ); > mlx4_dbg(dev, "Reporting Driver Version to FW: %s\n", dst); > } > > >--- >base-commit: cbf3a2cb156a2c911d8f38d8247814b4c07f49a2 >change-id: 20231011-strncpy-drivers-net-ethernet-mellanox-mlx4-fw-c-67809559dd1a > >Best regards, >-- >Justin Stitt <justinstitt@google.com> > Reviewed-by: Saeed Mahameed <saeedm@nvidia.com>
Hello: This patch was applied to netdev/net-next.git (main) by Jakub Kicinski <kuba@kernel.org>: On Wed, 11 Oct 2023 21:04:37 +0000 you wrote: > `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 `dst` to be NUL-terminated based on its use with format > strings: > | mlx4_dbg(dev, "Reporting Driver Version to FW: %s\n", dst); > > [...] Here is the summary with links: - net/mlx4_core: replace deprecated strncpy with strscpy https://git.kernel.org/netdev/net-next/c/88fca39b660b You are awesome, thank you!
diff --git a/drivers/net/ethernet/mellanox/mlx4/fw.c b/drivers/net/ethernet/mellanox/mlx4/fw.c index fe48d20d6118..0005d9e2c2d6 100644 --- a/drivers/net/ethernet/mellanox/mlx4/fw.c +++ b/drivers/net/ethernet/mellanox/mlx4/fw.c @@ -1967,7 +1967,7 @@ int mlx4_INIT_HCA(struct mlx4_dev *dev, struct mlx4_init_hca_param *param) if (dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_DRIVER_VERSION_TO_FW) { u8 *dst = (u8 *)(inbox + INIT_HCA_DRIVER_VERSION_OFFSET / 4); - strncpy(dst, DRV_NAME_FOR_FW, INIT_HCA_DRIVER_VERSION_SZ - 1); + strscpy(dst, DRV_NAME_FOR_FW, INIT_HCA_DRIVER_VERSION_SZ); mlx4_dbg(dev, "Reporting Driver Version to FW: %s\n", dst); }
`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 `dst` to be NUL-terminated based on its use with format strings: | mlx4_dbg(dev, "Reporting Driver Version to FW: %s\n", dst); Moreover, NUL-padding is not required. 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> --- Note: build-tested only. Found with: $ rg "strncpy\(" --- drivers/net/ethernet/mellanox/mlx4/fw.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- base-commit: cbf3a2cb156a2c911d8f38d8247814b4c07f49a2 change-id: 20231011-strncpy-drivers-net-ethernet-mellanox-mlx4-fw-c-67809559dd1a Best regards, -- Justin Stitt <justinstitt@google.com>