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 <azeemshaikh38@gmail.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230522155032.2336283-1-azeemshaikh38@gmail.com

diff --git a/drivers/gpu/drm/amd/amdgpu/atom.c b/drivers/gpu/drm/amd/amdgpu/atom.c
index 1c5d938..5f610e9 100644 (file)
--- 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 4ad5a32..bf3c411 100644 (file)
--- 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 783a6b8..795c366 100644 (file)
--- 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);