5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Paulo Miguel Almeida <paulo.miguel.almeida.rodenas@xxxxxxxxx> [ Upstream commit c81c5bd5cf2f428867e0bcfcccd4e4d2f8c68f51 ] 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. It's worth mentioning 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/239 Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836 [1] Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> Signed-off-by: Paulo Miguel Almeida <paulo.miguel.almeida.rodenas@xxxxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Stable-dep-of: 17c6baff3d5f ("drm/radeon: properly handle vbios fake edid sizing") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/radeon/atombios.h | 2 +- drivers/gpu/drm/radeon/radeon_atombios.c | 7 +++++-- 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/radeon/atombios.h b/drivers/gpu/drm/radeon/atombios.h index 4b86e8b450090..e3f4964647641 100644 --- a/drivers/gpu/drm/radeon/atombios.h +++ b/drivers/gpu/drm/radeon/atombios.h @@ -3615,7 +3615,7 @@ typedef struct _ATOM_FAKE_EDID_PATCH_RECORD { UCHAR ucRecordType; UCHAR ucFakeEDIDLength; - 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 diff --git a/drivers/gpu/drm/radeon/radeon_atombios.c b/drivers/gpu/drm/radeon/radeon_atombios.c index 9e0aa357585fd..2b3f702ef8c9b 100644 --- a/drivers/gpu/drm/radeon/radeon_atombios.c +++ b/drivers/gpu/drm/radeon/radeon_atombios.c @@ -1745,8 +1745,11 @@ struct radeon_encoder_atom_dig *radeon_atombios_get_lvds_info(struct } } 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; -- 2.43.0
