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/239
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836 [1]

Signed-off-by: Paulo Miguel Almeida <paulo.miguel.almeida.rode...@gmail.com>
---
 drivers/gpu/drm/radeon/atombios.h        |  2 +-
 drivers/gpu/drm/radeon/radeon_atombios.c | 12 ++++++++----
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/radeon/atombios.h 
b/drivers/gpu/drm/radeon/atombios.h
index da35a970fcc0..235e59b547a1 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 204127bad89c..48de2521f253 100644
--- a/drivers/gpu/drm/radeon/radeon_atombios.c
+++ b/drivers/gpu/drm/radeon/radeon_atombios.c
@@ -1716,7 +1716,7 @@ struct radeon_encoder_atom_dig 
*radeon_atombios_get_lvds_info(struct
                                                        max((int)EDID_LENGTH, 
(int)fake_edid_record->ucFakeEDIDLength);
                                                edid = kmalloc(edid_size, 
GFP_KERNEL);
                                                if (edid) {
-                                                       memcpy((u8 *)edid, (u8 
*)&fake_edid_record->ucFakeEDIDString[0],
+                                                       memcpy((u8 *)edid, (u8 
*)fake_edid_record->ucFakeEDIDString,
                                                               
fake_edid_record->ucFakeEDIDLength);
 
                                                        if 
(drm_edid_is_valid(edid)) {
@@ -1725,10 +1725,14 @@ struct radeon_encoder_atom_dig 
*radeon_atombios_get_lvds_info(struct
                                                        } 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(*fake_edid_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;
-- 
2.37.3

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