| Message ID | ZHO4/Z+iO+lqV4rW@work (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [next] drm/amdgpu/discovery: Replace fake flex-arrays with flexible-array members | expand |
On Sun, May 28, 2023 at 02:26:37PM -0600, Gustavo A. R. Silva wrote: > Zero-length and one-element arrays are deprecated, and we are moving > towards adopting C99 flexible-array members, instead. > > Use the DECLARE_FLEX_ARRAY() helper macro to transform zero-length > arrays in a union into flexible-array members. And replace a one-element > array with a C99 flexible-array member. > > Address the following warnings found with GCC-13 and > -fstrict-flex-arrays=3 enabled: > drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c:1009:89: warning: array subscript kk is outside array bounds of ‘uint32_t[0]’ {aka ‘unsigned int[]’} [-Warray-bounds=] > drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c:1007:94: warning: array subscript kk is outside array bounds of ‘uint64_t[0]’ {aka ‘long long unsigned int[]’} [-Warray-bounds=] > drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c:1310:94: warning: array subscript k is outside array bounds of ‘uint64_t[0]’ {aka ‘long long unsigned int[]’} [-Warray-bounds=] > drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c:1309:57: warning: array subscript k is outside array bounds of ‘uint32_t[0]’ {aka ‘unsigned int[]’} [-Warray-bounds=] > > This helps with the ongoing efforts to tighten the FORTIFY_SOURCE > routines on memcpy() and help us make progress towards globally > enabling -fstrict-flex-arrays=3 [1]. > > This results in no differences in binary output. > > Link: https://github.com/KSPP/linux/issues/21 > Link: https://github.com/KSPP/linux/issues/193 > Link: https://github.com/KSPP/linux/issues/300 > Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1] > Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org>
Applied. Thanks! On Tue, May 30, 2023 at 7:08 PM Kees Cook <keescook@chromium.org> wrote: > > On Sun, May 28, 2023 at 02:26:37PM -0600, Gustavo A. R. Silva wrote: > > Zero-length and one-element arrays are deprecated, and we are moving > > towards adopting C99 flexible-array members, instead. > > > > Use the DECLARE_FLEX_ARRAY() helper macro to transform zero-length > > arrays in a union into flexible-array members. And replace a one-element > > array with a C99 flexible-array member. > > > > Address the following warnings found with GCC-13 and > > -fstrict-flex-arrays=3 enabled: > > drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c:1009:89: warning: array subscript kk is outside array bounds of ‘uint32_t[0]’ {aka ‘unsigned int[]’} [-Warray-bounds=] > > drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c:1007:94: warning: array subscript kk is outside array bounds of ‘uint64_t[0]’ {aka ‘long long unsigned int[]’} [-Warray-bounds=] > > drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c:1310:94: warning: array subscript k is outside array bounds of ‘uint64_t[0]’ {aka ‘long long unsigned int[]’} [-Warray-bounds=] > > drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c:1309:57: warning: array subscript k is outside array bounds of ‘uint32_t[0]’ {aka ‘unsigned int[]’} [-Warray-bounds=] > > > > This helps with the ongoing efforts to tighten the FORTIFY_SOURCE > > routines on memcpy() and help us make progress towards globally > > enabling -fstrict-flex-arrays=3 [1]. > > > > This results in no differences in binary output. > > > > Link: https://github.com/KSPP/linux/issues/21 > > Link: https://github.com/KSPP/linux/issues/193 > > Link: https://github.com/KSPP/linux/issues/300 > > Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1] > > Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> > > Reviewed-by: Kees Cook <keescook@chromium.org> > > -- > Kees Cook
diff --git a/drivers/gpu/drm/amd/include/discovery.h b/drivers/gpu/drm/amd/include/discovery.h index 9181e57887db..f43e29722ef7 100644 --- a/drivers/gpu/drm/amd/include/discovery.h +++ b/drivers/gpu/drm/amd/include/discovery.h @@ -122,7 +122,7 @@ typedef struct ip_v3 uint8_t sub_revision : 4; /* HCID Sub-Revision */ uint8_t variant : 4; /* HW variant */ #endif - uint32_t base_address[1]; /* Base Address list. Corresponds to the num_base_address field*/ + uint32_t base_address[]; /* Base Address list. Corresponds to the num_base_address field*/ } ip_v3; typedef struct ip_v4 { @@ -140,8 +140,8 @@ typedef struct ip_v4 { uint8_t sub_revision : 4; /* HCID Sub-Revision */ #endif union { - uint32_t base_address[0]; /* 32-bit Base Address list. Corresponds to the num_base_address field*/ - uint64_t base_address_64[0]; /* 64-bit Base Address list. Corresponds to the num_base_address field*/ + DECLARE_FLEX_ARRAY(uint32_t, base_address); /* 32-bit Base Address list. Corresponds to the num_base_address field*/ + DECLARE_FLEX_ARRAY(uint64_t, base_address_64); /* 64-bit Base Address list. Corresponds to the num_base_address field*/ } __packed; } ip_v4;
Zero-length and one-element arrays are deprecated, and we are moving towards adopting C99 flexible-array members, instead. Use the DECLARE_FLEX_ARRAY() helper macro to transform zero-length arrays in a union into flexible-array members. And replace a one-element array with a C99 flexible-array member. Address the following warnings found with GCC-13 and -fstrict-flex-arrays=3 enabled: drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c:1009:89: warning: array subscript kk is outside array bounds of ‘uint32_t[0]’ {aka ‘unsigned int[]’} [-Warray-bounds=] drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c:1007:94: warning: array subscript kk is outside array bounds of ‘uint64_t[0]’ {aka ‘long long unsigned int[]’} [-Warray-bounds=] drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c:1310:94: warning: array subscript k is outside array bounds of ‘uint64_t[0]’ {aka ‘long long unsigned int[]’} [-Warray-bounds=] drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c:1309:57: warning: array subscript k is outside array bounds of ‘uint32_t[0]’ {aka ‘unsigned int[]’} [-Warray-bounds=] This helps with the ongoing efforts to tighten the FORTIFY_SOURCE routines on memcpy() and help us make progress towards globally enabling -fstrict-flex-arrays=3 [1]. This results in no differences in binary output. Link: https://github.com/KSPP/linux/issues/21 Link: https://github.com/KSPP/linux/issues/193 Link: https://github.com/KSPP/linux/issues/300 Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1] Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org> --- drivers/gpu/drm/amd/include/discovery.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)