[PATCH] [next] drm/amdgpu: Replace one-element array with flexible-array member

Paulo Miguel Almeida
2022-10-28T05:11:28Z

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.

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@gmail.com>
---
drivers/gpu/drm/amd/amdgpu/atombios_encoders.c | 10 +++++++---
drivers/gpu/drm/amd/include/atombios.h | 2 +-
2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c b/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c
index 6be9ac2b9c5b..6b5abf1249db 100644
--- a/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c
+++ b/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c
@@ -2079,10 +2079,14 @@ amdgpu_atombios_encoder_get_lcd_info(struct amdgpu_encoder *encoder)
} else
kfree(edid);
}
+
+ record += struct_size(fake_edid_record,
+ ucFakeEDIDString,
+ fake_edid_record->ucFakeEDIDLength);
+ } else {
+ /* empty fake edid record must be 3 bytes long */
+ record += sizeof(ATOM_FAKE_EDID_PATCH_RECORD) + 1;
}
- record += fake_edid_record->ucFakeEDIDLength ?
- fake_edid_record->ucFakeEDIDLength + 2 :
- sizeof(ATOM_FAKE_EDID_PATCH_RECORD);
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