From 4bc39754279832c0b6fe1ff76177dbf096f1a39d Mon Sep 17 00:00:00 2001 From: jsg Date: Mon, 7 Oct 2024 05:12:00 +0000 Subject: [PATCH] drm/amdgpu: properly handle vbios fake edid sizing From Alex Deucher 78b9e10b3bd1bb04c40f9f12b899951a6904772b in linux-6.6.y/6.6.54 8155566a26b8d6c1dd914f06a0c652e4e2f2adf1 in mainline linux --- .../drm/amd/amdgpu/amdgpu_atombios_encoders.c | 29 ++++++++++--------- 1 file changed, 16 insertions(+), 13 deletions(-) diff --git a/sys/dev/pci/drm/amd/amdgpu/amdgpu_atombios_encoders.c b/sys/dev/pci/drm/amd/amdgpu/amdgpu_atombios_encoders.c index d95b2dc7806..157e898dc38 100644 --- a/sys/dev/pci/drm/amd/amdgpu/amdgpu_atombios_encoders.c +++ b/sys/dev/pci/drm/amd/amdgpu/amdgpu_atombios_encoders.c @@ -2065,26 +2065,29 @@ amdgpu_atombios_encoder_get_lcd_info(struct amdgpu_encoder *encoder) fake_edid_record = (ATOM_FAKE_EDID_PATCH_RECORD *)record; if (fake_edid_record->ucFakeEDIDLength) { struct edid *edid; - int edid_size = - max((int)EDID_LENGTH, (int)fake_edid_record->ucFakeEDIDLength); - edid = kmalloc(edid_size, GFP_KERNEL); + int edid_size; + + if (fake_edid_record->ucFakeEDIDLength == 128) + edid_size = fake_edid_record->ucFakeEDIDLength; + else + edid_size = fake_edid_record->ucFakeEDIDLength * 128; + edid = kmemdup(&fake_edid_record->ucFakeEDIDString[0], + edid_size, GFP_KERNEL); if (edid) { - memcpy((u8 *)edid, (u8 *)&fake_edid_record->ucFakeEDIDString[0], - fake_edid_record->ucFakeEDIDLength); - if (drm_edid_is_valid(edid)) { adev->mode_info.bios_hardcoded_edid = edid; adev->mode_info.bios_hardcoded_edid_size = edid_size; - } else + } else { kfree(edid); + } } + record += struct_size(fake_edid_record, + ucFakeEDIDString, + edid_size); + } else { + /* empty fake edid record must be 3 bytes long */ + record += sizeof(ATOM_FAKE_EDID_PATCH_RECORD) + 1; } - record += fake_edid_record->ucFakeEDIDLength ? - struct_size(fake_edid_record, - ucFakeEDIDString, - fake_edid_record->ucFakeEDIDLength) : - /* empty fake edid record must be 3 bytes long */ - sizeof(ATOM_FAKE_EDID_PATCH_RECORD) + 1; break; case LCD_PANEL_RESOLUTION_RECORD_TYPE: panel_res_record = (ATOM_PANEL_RESOLUTION_PATCH_RECORD *)record; -- 2.20.1