In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memcpy(), memmove(), and memset(), avoid intentionally writing across neighboring fields. The "Board Parameters" members of the structs: struct atom_smc_dpm_info_v4_5 struct atom_smc_dpm_info_v4_6 struct atom_smc_dpm_info_v4_7 struct atom_smc_dpm_info_v4_10 are written to the corresponding members of the corresponding PPTable_t variables, but they lack destination size bounds checking, which means the compiler cannot verify at compile time that this is an intended and safe memcpy(). Since the header files are effectively immutable[1] and a struct_group() cannot be used, nor a common struct referenced by both sides of the memcpy() arguments, add a new helper, memcpy_trailing(), to perform the bounds checking at compile time. Replace the open-coded memcpy()s with memcpy_trailing() which includes enough context for the bounds checking. "objdump -d" shows no object code changes. [1] https://lore.kernel.org/lkml/e56aad3c-a06f-da07-f491-a894a570d78f@xxxxxxx Cc: Lijo Lazar <lijo.lazar@xxxxxxx> Cc: "Christian König" <christian.koenig@xxxxxxx> Cc: "Pan, Xinhui" <Xinhui.Pan@xxxxxxx> Cc: David Airlie <airlied@xxxxxxxx> Cc: Daniel Vetter <daniel@xxxxxxxx> Cc: Hawking Zhang <Hawking.Zhang@xxxxxxx> Cc: Feifei Xu <Feifei.Xu@xxxxxxx> Cc: Likun Gao <Likun.Gao@xxxxxxx> Cc: Jiawei Gu <Jiawei.Gu@xxxxxxx> Cc: Evan Quan <evan.quan@xxxxxxx> Cc: amd-gfx@xxxxxxxxxxxxxxxxxxxxx Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Link: https://lore.kernel.org/lkml/CADnq5_Npb8uYvd+R4UHgf-w8-cQj3JoODjviJR_Y9w9wqJ71mQ@xxxxxxxxxxxxxx --- Alex, I dropped your prior Acked-by, since the implementation is very different. If you're still happy with it, I can add it back. :) --- drivers/gpu/drm/amd/amdgpu/amdgpu.h | 25 +++++++++++++++++++ .../gpu/drm/amd/pm/swsmu/smu11/arcturus_ppt.c | 6 ++--- .../gpu/drm/amd/pm/swsmu/smu11/navi10_ppt.c | 8 +++--- .../drm/amd/pm/swsmu/smu13/aldebaran_ppt.c | 5 ++-- 4 files changed, 33 insertions(+), 11 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h index 96e895d6be35..4605934a4fb7 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h @@ -1446,4 +1446,29 @@ static inline int amdgpu_in_reset(struct amdgpu_device *adev) { return atomic_read(&adev->in_gpu_reset); } + +/** + * memcpy_trailing - Copy the end of one structure into the middle of another + * + * @dst: Pointer to destination struct + * @first_dst_member: The member name in @dst where the overwrite begins + * @last_dst_member: The member name in @dst where the overwrite ends after + * @src: Pointer to the source struct + * @first_src_member: The member name in @src where the copy begins + * + */ +#define memcpy_trailing(dst, first_dst_member, last_dst_member, \ + src, first_src_member) \ +({ \ + size_t __src_offset = offsetof(typeof(*(src)), first_src_member); \ + size_t __src_size = sizeof(*(src)) - __src_offset; \ + size_t __dst_offset = offsetof(typeof(*(dst)), first_dst_member); \ + size_t __dst_size = offsetofend(typeof(*(dst)), last_dst_member) - \ + __dst_offset; \ + BUILD_BUG_ON(__src_size != __dst_size); \ + __builtin_memcpy((u8 *)(dst) + __dst_offset, \ + (u8 *)(src) + __src_offset, \ + __dst_size); \ +}) + #endif diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu11/arcturus_ppt.c b/drivers/gpu/drm/amd/pm/swsmu/smu11/arcturus_ppt.c index 8ab58781ae13..1918e6232319 100644 --- a/drivers/gpu/drm/amd/pm/swsmu/smu11/arcturus_ppt.c +++ b/drivers/gpu/drm/amd/pm/swsmu/smu11/arcturus_ppt.c @@ -465,10 +465,8 @@ static int arcturus_append_powerplay_table(struct smu_context *smu) if ((smc_dpm_table->table_header.format_revision == 4) && (smc_dpm_table->table_header.content_revision == 6)) - memcpy(&smc_pptable->MaxVoltageStepGfx, - &smc_dpm_table->maxvoltagestepgfx, - sizeof(*smc_dpm_table) - offsetof(struct atom_smc_dpm_info_v4_6, maxvoltagestepgfx)); - + memcpy_trailing(smc_pptable, MaxVoltageStepGfx, BoardReserved, + smc_dpm_table, maxvoltagestepgfx); return 0; } diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu11/navi10_ppt.c b/drivers/gpu/drm/amd/pm/swsmu/smu11/navi10_ppt.c index 2e5d3669652b..b738042e064d 100644 --- a/drivers/gpu/drm/amd/pm/swsmu/smu11/navi10_ppt.c +++ b/drivers/gpu/drm/amd/pm/swsmu/smu11/navi10_ppt.c @@ -431,16 +431,16 @@ static int navi10_append_powerplay_table(struct smu_context *smu) switch (smc_dpm_table->table_header.content_revision) { case 5: /* nv10 and nv14 */ - memcpy(smc_pptable->I2cControllers, smc_dpm_table->I2cControllers, - sizeof(*smc_dpm_table) - sizeof(smc_dpm_table->table_header)); + memcpy_trailing(smc_pptable, I2cControllers, BoardReserved, + smc_dpm_table, I2cControllers); break; case 7: /* nv12 */ ret = amdgpu_atombios_get_data_table(adev, index, NULL, NULL, NULL, (uint8_t **)&smc_dpm_table_v4_7); if (ret) return ret; - memcpy(smc_pptable->I2cControllers, smc_dpm_table_v4_7->I2cControllers, - sizeof(*smc_dpm_table_v4_7) - sizeof(smc_dpm_table_v4_7->table_header)); + memcpy_trailing(smc_pptable, I2cControllers, BoardReserved, + smc_dpm_table_v4_7, I2cControllers); break; default: dev_err(smu->adev->dev, "smc_dpm_info with unsupported content revision %d!\n", diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c b/drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c index c8eefacfdd37..a6fd7ee314a9 100644 --- a/drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c +++ b/drivers/gpu/drm/amd/pm/swsmu/smu13/aldebaran_ppt.c @@ -409,9 +409,8 @@ static int aldebaran_append_powerplay_table(struct smu_context *smu) if ((smc_dpm_table->table_header.format_revision == 4) && (smc_dpm_table->table_header.content_revision == 10)) - memcpy(&smc_pptable->GfxMaxCurrent, - &smc_dpm_table->GfxMaxCurrent, - sizeof(*smc_dpm_table) - offsetof(struct atom_smc_dpm_info_v4_10, GfxMaxCurrent)); + memcpy_trailing(smc_pptable, GfxMaxCurrent, reserved, + smc_dpm_table, GfxMaxCurrent); return 0; } -- 2.30.2
