2023-05-22 16:08:31

by Azeem Shaikh

[permalink] [raw]
Subject: [PATCH] drm/radeon: Replace all non-returning strlcpy with strscpy

strlcpy() reads the entire source buffer first.
This read may exceed the destination size limit.
This is both inefficient and can lead to linear read
overflows if a source string is not NUL-terminated [1].
In an effort to remove strlcpy() completely [2], replace
strlcpy() here with strscpy().
No return values were used, so direct replacement is safe.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Signed-off-by: Azeem Shaikh <[email protected]>
---
drivers/gpu/drm/amd/amdgpu/atom.c | 2 +-
drivers/gpu/drm/radeon/radeon_atombios.c | 4 ++--
drivers/gpu/drm/radeon/radeon_combios.c | 4 ++--
3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/atom.c b/drivers/gpu/drm/amd/amdgpu/atom.c
index 1c5d9388ad0b..5f610e9a5f0f 100644
--- a/drivers/gpu/drm/amd/amdgpu/atom.c
+++ b/drivers/gpu/drm/amd/amdgpu/atom.c
@@ -1509,7 +1509,7 @@ struct atom_context *amdgpu_atom_parse(struct card_info *card, void *bios)
str = CSTR(idx);
if (*str != '\0') {
pr_info("ATOM BIOS: %s\n", str);
- strlcpy(ctx->vbios_version, str, sizeof(ctx->vbios_version));
+ strscpy(ctx->vbios_version, str, sizeof(ctx->vbios_version));
}

atom_rom_header = (struct _ATOM_ROM_HEADER *)CSTR(base);
diff --git a/drivers/gpu/drm/radeon/radeon_atombios.c b/drivers/gpu/drm/radeon/radeon_atombios.c
index 4ad5a328d920..bf3c411a55c5 100644
--- a/drivers/gpu/drm/radeon/radeon_atombios.c
+++ b/drivers/gpu/drm/radeon/radeon_atombios.c
@@ -2105,7 +2105,7 @@ static int radeon_atombios_parse_power_table_1_3(struct radeon_device *rdev)
const char *name = thermal_controller_names[power_info->info.
ucOverdriveThermalController];
info.addr = power_info->info.ucOverdriveControllerAddress >> 1;
- strlcpy(info.type, name, sizeof(info.type));
+ strscpy(info.type, name, sizeof(info.type));
i2c_new_client_device(&rdev->pm.i2c_bus->adapter, &info);
}
}
@@ -2355,7 +2355,7 @@ static void radeon_atombios_add_pplib_thermal_controller(struct radeon_device *r
struct i2c_board_info info = { };
const char *name = pp_lib_thermal_controller_names[controller->ucType];
info.addr = controller->ucI2cAddress >> 1;
- strlcpy(info.type, name, sizeof(info.type));
+ strscpy(info.type, name, sizeof(info.type));
i2c_new_client_device(&rdev->pm.i2c_bus->adapter, &info);
}
} else {
diff --git a/drivers/gpu/drm/radeon/radeon_combios.c b/drivers/gpu/drm/radeon/radeon_combios.c
index 783a6b8802d5..795c3667f6d6 100644
--- a/drivers/gpu/drm/radeon/radeon_combios.c
+++ b/drivers/gpu/drm/radeon/radeon_combios.c
@@ -2702,7 +2702,7 @@ void radeon_combios_get_power_modes(struct radeon_device *rdev)
struct i2c_board_info info = { };
const char *name = thermal_controller_names[thermal_controller];
info.addr = i2c_addr >> 1;
- strlcpy(info.type, name, sizeof(info.type));
+ strscpy(info.type, name, sizeof(info.type));
i2c_new_client_device(&rdev->pm.i2c_bus->adapter, &info);
}
}
@@ -2719,7 +2719,7 @@ void radeon_combios_get_power_modes(struct radeon_device *rdev)
struct i2c_board_info info = { };
const char *name = "f75375";
info.addr = 0x28;
- strlcpy(info.type, name, sizeof(info.type));
+ strscpy(info.type, name, sizeof(info.type));
i2c_new_client_device(&rdev->pm.i2c_bus->adapter, &info);
DRM_INFO("Possible %s thermal controller at 0x%02x\n",
name, info.addr);



2023-05-22 20:28:25

by Kees Cook

[permalink] [raw]
Subject: Re: [PATCH] drm/radeon: Replace all non-returning strlcpy with strscpy

On Mon, May 22, 2023 at 03:50:32PM +0000, Azeem Shaikh wrote:
> strlcpy() reads the entire source buffer first.
> This read may exceed the destination size limit.
> This is both inefficient and can lead to linear read
> overflows if a source string is not NUL-terminated [1].
> In an effort to remove strlcpy() completely [2], replace
> strlcpy() here with strscpy().
> No return values were used, so direct replacement is safe.
>
> [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
> [2] https://github.com/KSPP/linux/issues/89
>
> Signed-off-by: Azeem Shaikh <[email protected]>

Reviewed-by: Kees Cook <[email protected]>

--
Kees Cook

2023-05-22 20:46:40

by Deucher, Alexander

[permalink] [raw]
Subject: RE: [PATCH] drm/radeon: Replace all non-returning strlcpy with strscpy

[Public]

> -----Original Message-----
> From: Kees Cook <[email protected]>
> Sent: Monday, May 22, 2023 4:15 PM
> To: Azeem Shaikh <[email protected]>
> Cc: Deucher, Alexander <[email protected]>; Koenig, Christian
> <[email protected]>; Pan, Xinhui <[email protected]>; linux-
> [email protected]; [email protected]; linux-
> [email protected]; David Airlie <[email protected]>; Daniel Vetter
> <[email protected]>; [email protected]
> Subject: Re: [PATCH] drm/radeon: Replace all non-returning strlcpy with
> strscpy
>
> On Mon, May 22, 2023 at 03:50:32PM +0000, Azeem Shaikh wrote:
> > strlcpy() reads the entire source buffer first.
> > This read may exceed the destination size limit.
> > This is both inefficient and can lead to linear read overflows if a
> > source string is not NUL-terminated [1].
> > In an effort to remove strlcpy() completely [2], replace
> > strlcpy() here with strscpy().
> > No return values were used, so direct replacement is safe.
> >
> > [1]
> >
> https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
> > [2] https://github.com/KSPP/linux/issues/89
> >
> > Signed-off-by: Azeem Shaikh <[email protected]>
>
> Reviewed-by: Kees Cook <[email protected]>
>

Acked-by: Alex Deucher <[email protected]>

Ack to take this through whatever tree makes sense if you are trying to batch all of these up. Otherwise, I can pick them up.

Alex

2023-05-22 21:13:15

by Kees Cook

[permalink] [raw]
Subject: Re: [PATCH] drm/radeon: Replace all non-returning strlcpy with strscpy

On Mon, 22 May 2023 15:50:32 +0000, Azeem Shaikh wrote:
> strlcpy() reads the entire source buffer first.
> This read may exceed the destination size limit.
> This is both inefficient and can lead to linear read
> overflows if a source string is not NUL-terminated [1].
> In an effort to remove strlcpy() completely [2], replace
> strlcpy() here with strscpy().
> No return values were used, so direct replacement is safe.
>
> [...]

Applied to for-next/hardening, thanks!

[1/1] drm/radeon: Replace all non-returning strlcpy with strscpy
https://git.kernel.org/kees/c/76ea3f6ef93f

--
Kees Cook