| Message ID | 20230913-strncpy-drivers-crypto-intel-qat-qat_common-qat_uclo-c-v1-1-88a6c07fc924@google.com (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Herbert Xu |
| Headers | show |
| Series | crypto: qat - refactor deprecated strncpy | expand |
On Wed, Sep 13, 2023 at 12:51:05AM +0000, Justin Stitt wrote: > `strncpy` is deprecated for use on NUL-terminated destination strings [1]. > > We should prefer more robust and less ambiguous string interfaces. > > `buf` is expected to be NUL-terminated for its eventual use in > `kstrtoul()` and NUL-padding is not required. > > Due to the above, a suitable replacement is `strscpy` [2] due to the > fact that it guarantees NUL-termination on the destination buffer. > > 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> Acked-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com> > --- > Note: build-tested only. Reviewed and tested on dh895xcc, the only device impacted by this change. All good. Thanks,
On Wed, Sep 13, 2023 at 12:51:05AM +0000, Justin Stitt wrote: > `strncpy` is deprecated for use on NUL-terminated destination strings [1]. > > We should prefer more robust and less ambiguous string interfaces. > > `buf` is expected to be NUL-terminated for its eventual use in > `kstrtoul()` and NUL-padding is not required. > > Due to the above, a suitable replacement is `strscpy` [2] due to the > fact that it guarantees NUL-termination on the destination buffer. > > 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. > --- > drivers/crypto/intel/qat/qat_common/qat_uclo.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/crypto/intel/qat/qat_common/qat_uclo.c b/drivers/crypto/intel/qat/qat_common/qat_uclo.c > index ce837bcc1cab..e2f82128043e 100644 > --- a/drivers/crypto/intel/qat/qat_common/qat_uclo.c > +++ b/drivers/crypto/intel/qat/qat_common/qat_uclo.c > @@ -200,7 +200,7 @@ static int qat_uclo_parse_num(char *str, unsigned int *num) > unsigned long ae = 0; > int i; > > - strncpy(buf, str, 15); > + strscpy(buf, str, sizeof(buf)); > for (i = 0; i < 16; i++) { > if (!isdigit(buf[i])) { I was initially worried when I saw this walking the entire contents, but I see it is explicitly zeroed on the stack first, so this is fine: char buf[16] = {0}; Reviewed-by: Kees Cook <keescook@chromium.org> -Kees > buf[i] = '\0'; > > --- > base-commit: 2dde18cd1d8fac735875f2e4987f11817cc0bc2c > change-id: 20230913-strncpy-drivers-crypto-intel-qat-qat_common-qat_uclo-c-0f4b16830f59 > > Best regards, > -- > Justin Stitt <justinstitt@google.com> >
On Wed, Sep 13, 2023 at 12:51:05AM +0000, Justin Stitt wrote: > `strncpy` is deprecated for use on NUL-terminated destination strings [1]. > > We should prefer more robust and less ambiguous string interfaces. > > `buf` is expected to be NUL-terminated for its eventual use in > `kstrtoul()` and NUL-padding is not required. > > Due to the above, a suitable replacement is `strscpy` [2] due to the > fact that it guarantees NUL-termination on the destination buffer. > > 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. > --- > drivers/crypto/intel/qat/qat_common/qat_uclo.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) Patch applied. Thanks.
diff --git a/drivers/crypto/intel/qat/qat_common/qat_uclo.c b/drivers/crypto/intel/qat/qat_common/qat_uclo.c index ce837bcc1cab..e2f82128043e 100644 --- a/drivers/crypto/intel/qat/qat_common/qat_uclo.c +++ b/drivers/crypto/intel/qat/qat_common/qat_uclo.c @@ -200,7 +200,7 @@ static int qat_uclo_parse_num(char *str, unsigned int *num) unsigned long ae = 0; int i; - strncpy(buf, str, 15); + strscpy(buf, str, sizeof(buf)); for (i = 0; i < 16; i++) { if (!isdigit(buf[i])) { buf[i] = '\0';
`strncpy` is deprecated for use on NUL-terminated destination strings [1]. We should prefer more robust and less ambiguous string interfaces. `buf` is expected to be NUL-terminated for its eventual use in `kstrtoul()` and NUL-padding is not required. Due to the above, a suitable replacement is `strscpy` [2] due to the fact that it guarantees NUL-termination on the destination buffer. 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. --- drivers/crypto/intel/qat/qat_common/qat_uclo.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- base-commit: 2dde18cd1d8fac735875f2e4987f11817cc0bc2c change-id: 20230913-strncpy-drivers-crypto-intel-qat-qat_common-qat_uclo-c-0f4b16830f59 Best regards, -- Justin Stitt <justinstitt@google.com>