Prefer common check_add_overflow() from overflow.h over the locally rolled versions of it. While check_add_overflow() does require a variable to assign to, unlike add_overflows_t(), it's still better than having multiple versions around.
Cc: Kees Cook <[email protected]> Signed-off-by: Jani Nikula <[email protected]> --- drivers/gpu/drm/i915/display/intel_fb.c | 6 +++--- drivers/gpu/drm/i915/i915_utils.h | 14 -------------- 2 files changed, 3 insertions(+), 17 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_fb.c b/drivers/gpu/drm/i915/display/intel_fb.c index 3ea6470d6d92..86b443433e8b 100644 --- a/drivers/gpu/drm/i915/display/intel_fb.c +++ b/drivers/gpu/drm/i915/display/intel_fb.c @@ -1106,7 +1106,7 @@ static int intel_fb_offset_to_xy(int *x, int *y, { struct drm_i915_private *i915 = to_i915(fb->dev); unsigned int height; - u32 alignment; + u32 alignment, unused; if (DISPLAY_VER(i915) >= 12 && !intel_fb_needs_pot_stride_remap(to_intel_framebuffer(fb)) && @@ -1128,8 +1128,8 @@ static int intel_fb_offset_to_xy(int *x, int *y, height = ALIGN(height, intel_tile_height(fb, color_plane)); /* Catch potential overflows early */ - if (add_overflows_t(u32, mul_u32_u32(height, fb->pitches[color_plane]), - fb->offsets[color_plane])) { + if (check_add_overflow(mul_u32_u32(height, fb->pitches[color_plane]), + fb->offsets[color_plane], &unused)) { drm_dbg_kms(&i915->drm, "Bad offset 0x%08x or pitch %d for color plane %d\n", fb->offsets[color_plane], fb->pitches[color_plane], diff --git a/drivers/gpu/drm/i915/i915_utils.h b/drivers/gpu/drm/i915/i915_utils.h index b45ef0560611..06ec6ceb61d5 100644 --- a/drivers/gpu/drm/i915/i915_utils.h +++ b/drivers/gpu/drm/i915/i915_utils.h @@ -73,20 +73,6 @@ bool i915_error_injected(void); __i915_printk(i915, i915_error_injected() ? KERN_DEBUG : KERN_ERR, \ fmt, ##__VA_ARGS__) -#if defined(GCC_VERSION) && GCC_VERSION >= 70000 -#define add_overflows_t(T, A, B) \ - __builtin_add_overflow_p((A), (B), (T)0) -#else -#define add_overflows_t(T, A, B) ({ \ - typeof(A) a = (A); \ - typeof(B) b = (B); \ - (T)(a + b) < a; \ -}) -#endif - -#define add_overflows(A, B) \ - add_overflows_t(typeof((A) + (B)), (A), (B)) - #define range_overflows(start, size, max) ({ \ typeof(start) start__ = (start); \ typeof(size) size__ = (size); \ -- 2.39.2
