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

From: Azeem Shaikh
Date: Mon May 22 2023 - 11:50:42 EST


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 <azeemshaikh38@xxxxxxxxx>
---
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);