`strncpy` is deprecated for use on NUL-terminated destination strings [1]. We see that `prop->cpucp_info.card_name` is supposed to be NUL-terminated based on its usage within `__hwmon_device_register()` (wherein it's called "name"): | if (name && (!strlen(name) || strpbrk(name, "-* \t\n"))) | dev_warn(dev, | "hwmon: '%s' is not a valid name attribute, please fix\n", | name); A suitable replacement is `strscpy_pad` [2] due to the fact that it guarantees both NUL-termination and NUL-padding on its destination buffer. NUL-padding on `prop->cpucp_info.card_name` is not strictly necessary as `hdev->prop` is explicitly zero-initialized but should be used regardless as it gets copied out to userspace directly -- as per Kees' suggestion. Link: 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@xxxxxxxxxxxxxxx Signed-off-by: Justin Stitt <justinstitt@xxxxxxxxxx> Suggested-by: Kees Cook <keescook@xxxxxxxxxxxx> --- Note: build-tested only This patch combines three previous strncpy refactor patches into one. 1) https://lore.kernel.org/all/20230824-strncpy-drivers-accel-habanalabs-gaudi-gaudi-c-v1-1-a7fb9054734c@xxxxxxxxxx/ 2) https://lore.kernel.org/all/20230824-strncpy-drivers-accel-habanalabs-gaudi2-gaudi2-c-v1-1-1a37b65576b4@xxxxxxxxxx/ 3) https://lore.kernel.org/all/20230824-strncpy-drivers-accel-habanalabs-goya-goya-c-v1-1-b81d5639e7a3@xxxxxxxxxx/ --- drivers/accel/habanalabs/gaudi/gaudi.c | 4 ++-- drivers/accel/habanalabs/gaudi2/gaudi2.c | 4 ++-- drivers/accel/habanalabs/goya/goya.c | 4 ++-- 3 files changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/accel/habanalabs/gaudi/gaudi.c b/drivers/accel/habanalabs/gaudi/gaudi.c index 056e2ef44afb..1b5fe4d0cf5d 100644 --- a/drivers/accel/habanalabs/gaudi/gaudi.c +++ b/drivers/accel/habanalabs/gaudi/gaudi.c @@ -660,7 +660,7 @@ static int gaudi_set_fixed_properties(struct hl_device *hdev) prop->pcie_dbi_base_address = mmPCIE_DBI_BASE; prop->pcie_aux_dbi_reg_addr = CFG_BASE + mmPCIE_AUX_DBI; - strncpy(prop->cpucp_info.card_name, GAUDI_DEFAULT_CARD_NAME, + strscpy_pad(prop->cpucp_info.card_name, GAUDI_DEFAULT_CARD_NAME, CARD_NAME_MAX_LEN); prop->max_pending_cs = GAUDI_MAX_PENDING_CS; @@ -8000,7 +8000,7 @@ static int gaudi_cpucp_info_get(struct hl_device *hdev) return rc; if (!strlen(prop->cpucp_info.card_name)) - strncpy(prop->cpucp_info.card_name, GAUDI_DEFAULT_CARD_NAME, + strscpy_pad(prop->cpucp_info.card_name, GAUDI_DEFAULT_CARD_NAME, CARD_NAME_MAX_LEN); hdev->card_type = le32_to_cpu(hdev->asic_prop.cpucp_info.card_type); diff --git a/drivers/accel/habanalabs/gaudi2/gaudi2.c b/drivers/accel/habanalabs/gaudi2/gaudi2.c index 20c4583f12b0..2ba7a50103bc 100644 --- a/drivers/accel/habanalabs/gaudi2/gaudi2.c +++ b/drivers/accel/habanalabs/gaudi2/gaudi2.c @@ -2431,7 +2431,7 @@ static int gaudi2_set_fixed_properties(struct hl_device *hdev) prop->pcie_dbi_base_address = CFG_BASE + mmPCIE_DBI_BASE; prop->pcie_aux_dbi_reg_addr = CFG_BASE + mmPCIE_AUX_DBI; - strncpy(prop->cpucp_info.card_name, GAUDI2_DEFAULT_CARD_NAME, CARD_NAME_MAX_LEN); + strscpy_pad(prop->cpucp_info.card_name, GAUDI2_DEFAULT_CARD_NAME, CARD_NAME_MAX_LEN); prop->mme_master_slave_mode = 1; @@ -2884,7 +2884,7 @@ static int gaudi2_cpucp_info_get(struct hl_device *hdev) } if (!strlen(prop->cpucp_info.card_name)) - strncpy(prop->cpucp_info.card_name, GAUDI2_DEFAULT_CARD_NAME, CARD_NAME_MAX_LEN); + strscpy_pad(prop->cpucp_info.card_name, GAUDI2_DEFAULT_CARD_NAME, CARD_NAME_MAX_LEN); /* Overwrite binning masks with the actual binning values from F/W */ hdev->dram_binning = prop->cpucp_info.dram_binning_mask; diff --git a/drivers/accel/habanalabs/goya/goya.c b/drivers/accel/habanalabs/goya/goya.c index 7c685e6075f6..024ccf2e159b 100644 --- a/drivers/accel/habanalabs/goya/goya.c +++ b/drivers/accel/habanalabs/goya/goya.c @@ -466,7 +466,7 @@ int goya_set_fixed_properties(struct hl_device *hdev) prop->pcie_dbi_base_address = mmPCIE_DBI_BASE; prop->pcie_aux_dbi_reg_addr = CFG_BASE + mmPCIE_AUX_DBI; - strncpy(prop->cpucp_info.card_name, GOYA_DEFAULT_CARD_NAME, + strscpy_pad(prop->cpucp_info.card_name, GOYA_DEFAULT_CARD_NAME, CARD_NAME_MAX_LEN); prop->max_pending_cs = GOYA_MAX_PENDING_CS; @@ -5122,7 +5122,7 @@ int goya_cpucp_info_get(struct hl_device *hdev) } if (!strlen(prop->cpucp_info.card_name)) - strncpy(prop->cpucp_info.card_name, GOYA_DEFAULT_CARD_NAME, + strscpy_pad(prop->cpucp_info.card_name, GOYA_DEFAULT_CARD_NAME, CARD_NAME_MAX_LEN); return 0; --- base-commit: 706a741595047797872e669b3101429ab8d378ef change-id: 20230825-strncpy-habanalabs-combined-c43b1d11960e Best regards, -- Justin Stitt <justinstitt@xxxxxxxxxx>