One-element arrays are deprecated, and we are replacing them with flexible array members instead. So, replace one-element array with flexible-array member in struct _ATOM_FAKE_EDID_PATCH_RECORD and refactor the rest of the code accordingly. Important to mention is that doing a build before/after this patch results in no binary output differences. This helps with the ongoing efforts to tighten the FORTIFY_SOURCE routines on memcpy() and help us make progress towards globally enabling -fstrict-flex-arrays=3 [1]. Link: https://github.com/KSPP/linux/issues/79 Link: https://github.com/KSPP/linux/issues/238 Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836 [1] Signed-off-by: Paulo Miguel Almeida <paulo.miguel.almeida.rodenas@xxxxxxxxx> --- Changelog: v2: no binary output differences patch; report binary changes findings on commit log. Res: Kees Cook v1: https://lore.kernel.org/lkml/Y1tkWdwPUp+UdpM0@xxxxxxxxxxxxxxx/ --- drivers/gpu/drm/amd/amdgpu/atombios_encoders.c | 7 +++++-- drivers/gpu/drm/amd/include/atombios.h | 2 +- 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c b/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c index 6be9ac2b9c5b..18ae9433e463 100644 --- a/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c +++ b/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c @@ -2081,8 +2081,11 @@ amdgpu_atombios_encoder_get_lcd_info(struct amdgpu_encoder *encoder) } } record += fake_edid_record->ucFakeEDIDLength ? - fake_edid_record->ucFakeEDIDLength + 2 : - sizeof(ATOM_FAKE_EDID_PATCH_RECORD); + 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; diff --git a/drivers/gpu/drm/amd/include/atombios.h b/drivers/gpu/drm/amd/include/atombios.h index 15943bc21bc5..b5b1d073f8e2 100644 --- a/drivers/gpu/drm/amd/include/atombios.h +++ b/drivers/gpu/drm/amd/include/atombios.h @@ -4107,7 +4107,7 @@ typedef struct _ATOM_FAKE_EDID_PATCH_RECORD { UCHAR ucRecordType; UCHAR ucFakeEDIDLength; // = 128 means EDID length is 128 bytes, otherwise the EDID length = ucFakeEDIDLength*128 - UCHAR ucFakeEDIDString[1]; // This actually has ucFakeEdidLength elements. + UCHAR ucFakeEDIDString[]; // This actually has ucFakeEdidLength elements. } ATOM_FAKE_EDID_PATCH_RECORD; typedef struct _ATOM_PANEL_RESOLUTION_PATCH_RECORD -- 2.37.3
