From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 203A85867D8; Wed, 9 Sep 2026 14:32:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788964328; cv=none; b=lavHFsix1a7Lqw2lFvIIGcRmPqn24Hvl0ehbHfRmcRaeieu4QucYbEOxm/ArMNZV6FKCJAMeVGe2wdwtYscz4HbbXiO1mLZIxQNfjJvs2JkahV+HT8/5zu6VWHdXdJvd8HIHqn0uEnFwf11ou7ehZT70JPGaHpfFTXQkBIBVHxc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788964328; c=relaxed/simple; bh=SO41a/Pbja8oS/CkZrhd1QcTp6/bsOAgiaBVobHSdQ8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lVnR5Se/XBoScyJ3XbZvHhoggrU+C2PKOhVDfhuUP5OQKNC4+N0TMXh3tCA2K2egzkvNx6itVGmzs3GdLV5Ih67B3F1ZvFir2fYYwWeNQoA9a/SLmXjCHXheGYGc6ZnhZ3oQraByi466RFvMgBItg801+SYpqnpdxRIWVo9/uHs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=QOzJDjdG; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="QOzJDjdG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 79E491F00A3A; Wed, 9 Sep 2026 14:32:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788964327; bh=N2uJi/zaR+iMx187isZUJb5F721HYaMEfMnegZXSwUM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=QOzJDjdGecMAGTZbnXbTmWybcRr7pOAVnIaDXDsmUVLYqYPBmh38HCyxnrTY921Yi VOrgIzcAqmkB+N5vUjIXWd0GVa3/5K9wOt+9y1U4K7fmVM6uhBfnKLCOVbLxjs91H0 PEa3h8gMyvRXPXCVJdIHdRDcwp0ohOfBMwFNTIhI= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Harry Wentland , Melissa Wen , Daniel Wheeler , Alex Deucher Subject: [PATCH 6.18 385/583] drm/amd/display: validate plane degamma LUT size for private color prop Date: Wed, 9 Sep 2026 15:41:10 +0200 Message-ID: <20260909134251.332364691@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260909134237.773280130@linuxfoundation.org> References: <20260909134237.773280130@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Harry Wentland commit e4c3ab59021e7c146a84b6671f0d530972bd58b4 upstream. Unlike the CRTC degamma path, which is guarded by amdgpu_dm_verify_lut_sizes(), the per-plane degamma LUT size was never validated before use. __set_dm_plane_degamma() passed the user-supplied size straight into __is_lut_linear() and, for a non-linear LUT, into __set_input_tf() -> __drm_lut_to_dc_gamma(), the latter always iterating MAX_COLOR_LUT_ENTRIES entries regardless of the actual LUT size. A malformed AMD_PLANE_DEGAMMA_LUT blob (e.g. a single entry) could thus trigger a divide-by-zero in __is_lut_linear() or an out-of-bounds read in __drm_lut_to_dc_gamma(). Reject any plane degamma LUT whose size does not match MAX_COLOR_LUT_ENTRIES, mirroring the invariant the code already asserts a few lines below (and which the CRTC path enforces). The AMD_PLANE_DEGAMMA_LUT property is only exposed on builds with AMD_PRIVATE_COLOR defined. Fixes: 980f8710075a ("drm/amd/display: add plane degamma TF and LUT support") Cc: stable@vger.kernel.org Signed-off-by: Harry Wentland Reviewed-by: Melissa Wen Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c @@ -1149,6 +1149,13 @@ __set_dm_plane_degamma(struct drm_plane_ degamma_lut = __extract_blob_lut(dm_plane_state->degamma_lut, °amma_size); + if (degamma_lut && degamma_size != MAX_COLOR_LUT_ENTRIES) { + drm_dbg(plane_state->state->dev, + "Invalid Plane Degamma LUT size. Should be %u but got %u.\n", + MAX_COLOR_LUT_ENTRIES, degamma_size); + return -EINVAL; + } + has_degamma_lut = degamma_lut && !__is_lut_linear(degamma_lut, degamma_size);