2021-08-19 20:16:39

by Kees Cook

[permalink] [raw]
Subject: [PATCH] drm/amd/pm: And destination bounds checking to struct copy

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/[email protected]

Cc: Lijo Lazar <[email protected]>
Cc: "Christian König" <[email protected]>
Cc: "Pan, Xinhui" <[email protected]>
Cc: David Airlie <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: Hawking Zhang <[email protected]>
Cc: Feifei Xu <[email protected]>
Cc: Likun Gao <[email protected]>
Cc: Jiawei Gu <[email protected]>
Cc: Evan Quan <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
Link: https://lore.kernel.org/lkml/CADnq5_Npb8uYvd+R4UHgf-w8-cQj3JoODjviJR_Y9w9wqJ71mQ@mail.gmail.com
---
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


2021-08-20 15:31:28

by Alex Deucher

[permalink] [raw]
Subject: Re: [PATCH] drm/amd/pm: And destination bounds checking to struct copy

On Thu, Aug 19, 2021 at 4:14 PM Kees Cook <[email protected]> wrote:
>
> 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/[email protected]
>
> Cc: Lijo Lazar <[email protected]>
> Cc: "Christian König" <[email protected]>
> Cc: "Pan, Xinhui" <[email protected]>
> Cc: David Airlie <[email protected]>
> Cc: Daniel Vetter <[email protected]>
> Cc: Hawking Zhang <[email protected]>
> Cc: Feifei Xu <[email protected]>
> Cc: Likun Gao <[email protected]>
> Cc: Jiawei Gu <[email protected]>
> Cc: Evan Quan <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Kees Cook <[email protected]>
> Link: https://lore.kernel.org/lkml/CADnq5_Npb8uYvd+R4UHgf-w8-cQj3JoODjviJR_Y9w9wqJ71mQ@mail.gmail.com
> ---
> 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. :)

This looks reasonable to me:
Acked-by: Alex Deucher <[email protected]>

> ---
> 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
>

2021-08-23 05:41:26

by Lazar, Lijo

[permalink] [raw]
Subject: Re: [PATCH] drm/amd/pm: And destination bounds checking to struct copy

Thanks Kees!

Reviewed-by: Lijo Lazar <[email protected]>

Thanks,
Lijo

On 8/20/2021 1:44 AM, Kees Cook wrote:
> 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://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore.kernel.org%2Flkml%2Fe56aad3c-a06f-da07-f491-a894a570d78f%40amd.com&amp;data=04%7C01%7Clijo.lazar%40amd.com%7Cb0567a0252604c8c84cd08d9634dfe39%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637650008892964983%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=UikQRh9WCwr8H29bBqZu3iLJt095Es9mIG5mVwPJpC0%3D&amp;reserved=0
>
> Cc: Lijo Lazar <[email protected]>
> Cc: "Christian König" <[email protected]>
> Cc: "Pan, Xinhui" <[email protected]>
> Cc: David Airlie <[email protected]>
> Cc: Daniel Vetter <[email protected]>
> Cc: Hawking Zhang <[email protected]>
> Cc: Feifei Xu <[email protected]>
> Cc: Likun Gao <[email protected]>
> Cc: Jiawei Gu <[email protected]>
> Cc: Evan Quan <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Kees Cook <[email protected]>
> Link: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore.kernel.org%2Flkml%2FCADnq5_Npb8uYvd%2BR4UHgf-w8-cQj3JoODjviJR_Y9w9wqJ71mQ%40mail.gmail.com&amp;data=04%7C01%7Clijo.lazar%40amd.com%7Cb0567a0252604c8c84cd08d9634dfe39%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637650008892964983%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=LVHdf9C1jx6eIB2BQ%2Bm5q4o5KcRzBWJi7PhNviKzKGM%3D&amp;reserved=0
> ---
> 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;
> }
>
>

2021-08-23 06:29:57

by Christian König

[permalink] [raw]
Subject: Re: [PATCH] drm/amd/pm: And destination bounds checking to struct copy



Am 19.08.21 um 22:14 schrieb Kees Cook:
> 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://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore.kernel.org%2Flkml%2Fe56aad3c-a06f-da07-f491-a894a570d78f%40amd.com&amp;data=04%7C01%7Cchristian.koenig%40amd.com%7C63c17764a7c84cc85d7a08d9634dfe37%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637650008924776466%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=TbxGZSLP0HegTcF4qFn0cnFW8SR47X0wmuf1y75ygFw%3D&amp;reserved=0
>
> Cc: Lijo Lazar <[email protected]>
> Cc: "Christian König" <[email protected]>
> Cc: "Pan, Xinhui" <[email protected]>
> Cc: David Airlie <[email protected]>
> Cc: Daniel Vetter <[email protected]>
> Cc: Hawking Zhang <[email protected]>
> Cc: Feifei Xu <[email protected]>
> Cc: Likun Gao <[email protected]>
> Cc: Jiawei Gu <[email protected]>
> Cc: Evan Quan <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Signed-off-by: Kees Cook <[email protected]>
> Link: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore.kernel.org%2Flkml%2FCADnq5_Npb8uYvd%2BR4UHgf-w8-cQj3JoODjviJR_Y9w9wqJ71mQ%40mail.gmail.com&amp;data=04%7C01%7Cchristian.koenig%40amd.com%7C63c17764a7c84cc85d7a08d9634dfe37%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637650008924786462%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=yCGfiaYVLayZKc9Ahq1axpjztJQ8KVIJ4tMI6Z7LoMQ%3D&amp;reserved=0
> ---
> 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) \

Please don't add a function like this into amdgpu.h, especially when it
is only used by the SMU code.

And please give it an amdgpu_ prefix so that we are not confusing it
with a core function.

Apart from that looks good to me.

Thanks,
Christian.

> +({ \
> + 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;
> }
>

2021-08-23 14:25:37

by Kees Cook

[permalink] [raw]
Subject: Re: [PATCH] drm/amd/pm: And destination bounds checking to struct copy



On August 22, 2021 11:28:54 PM PDT, "Christian König" <[email protected]> wrote:
>
>
>Am 19.08.21 um 22:14 schrieb Kees Cook:
>> [...]
>> 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) \
>
>Please don't add a function like this into amdgpu.h, especially when it
>is only used by the SMU code.

Sure, I'm happy to move it. It wasn't clear to me which headers were considered "immutable". Which header should I put this in?

>And please give it an amdgpu_ prefix so that we are not confusing it
>with a core function.

Sure, I will include that.

>Apart from that looks good to me.

Thanks!

-Kees

2021-08-23 19:03:59

by Christian König

[permalink] [raw]
Subject: Re: [PATCH] drm/amd/pm: And destination bounds checking to struct copy

Am 23.08.21 um 16:23 schrieb Kees Cook:
>
> On August 22, 2021 11:28:54 PM PDT, "Christian König" <[email protected]> wrote:
>>
>> Am 19.08.21 um 22:14 schrieb Kees Cook:
>>> [...]
>>> 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) \
>> Please don't add a function like this into amdgpu.h, especially when it
>> is only used by the SMU code.
> Sure, I'm happy to move it. It wasn't clear to me which headers were considered "immutable". Which header should I put this in?

I think amdgpu_smuio.h, but I'm not 100% sure. Alex do you have a better
idea?

We don't want to put anything new into amdgpu.h any more since this is
basically only a legacy leftover.

Thanks,
Christian.

>
>> And please give it an amdgpu_ prefix so that we are not confusing it
>> with a core function.
> Sure, I will include that.
>
>> Apart from that looks good to me.
> Thanks!
>
> -Kees

2021-08-23 19:14:47

by Deucher, Alexander

[permalink] [raw]
Subject: RE: [PATCH] drm/amd/pm: And destination bounds checking to struct copy

[Public]

> -----Original Message-----
> From: Koenig, Christian <[email protected]>
> Sent: Monday, August 23, 2021 3:02 PM
> To: Kees Cook <[email protected]>; Lazar, Lijo
> <[email protected]>
> Cc: Pan, Xinhui <[email protected]>; David Airlie <[email protected]>;
> Daniel Vetter <[email protected]>; Zhang, Hawking
> <[email protected]>; Xu, Feifei <[email protected]>; Gao, Likun
> <[email protected]>; Gu, JiaWei (Will) <[email protected]>; Quan,
> Evan <[email protected]>; [email protected]; dri-
> [email protected]; Deucher, Alexander
> <[email protected]>; Tuikov, Luben
> <[email protected]>; Grodzovsky, Andrey
> <[email protected]>; Li, Dennis <[email protected]>;
> Sundararaju, Sathishkumar <[email protected]>; Kim,
> Jonathan <[email protected]>; Wang, Kevin(Yang)
> <[email protected]>; Nieto, David M <[email protected]>; Feng,
> Kenneth <[email protected]>; Lee Jones <[email protected]>;
> Clements, John <[email protected]>; [email protected];
> [email protected]
> Subject: Re: [PATCH] drm/amd/pm: And destination bounds checking to
> struct copy
>
> Am 23.08.21 um 16:23 schrieb Kees Cook:
> >
> > On August 22, 2021 11:28:54 PM PDT, "Christian König"
> <[email protected]> wrote:
> >>
> >> Am 19.08.21 um 22:14 schrieb Kees Cook:
> >>> [...]
> >>> 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) \
> >> Please don't add a function like this into amdgpu.h, especially when
> >> it is only used by the SMU code.
> > Sure, I'm happy to move it. It wasn't clear to me which headers were
> considered "immutable". Which header should I put this in?
>
> I think amdgpu_smuio.h, but I'm not 100% sure. Alex do you have a better
> idea?
>

No, that's for the SMUIO callbacks for the IP block. Please use drivers/gpu/drm/amd/pm/inc/amdgpu_smu.h

Alex

> We don't want to put anything new into amdgpu.h any more since this is
> basically only a legacy leftover.
>
> Thanks,
> Christian.
>
> >
> >> And please give it an amdgpu_ prefix so that we are not confusing it
> >> with a core function.
> > Sure, I will include that.
> >
> >> Apart from that looks good to me.
> > Thanks!
> >
> > -Kees