[PATCH] drm/nouveau/disp: More DP_RECEIVER_CAP_SIZE array fixes

From: Kees Cook
Date: Sat Feb 04 2023 - 13:43:21 EST


More arrays (and arguments) for dcpd were set to 16, when it looks like
DP_RECEIVER_CAP_SIZE (15) should be used. Fix the remaining cases, seen
with GCC 13:

../drivers/gpu/drm/nouveau/nvif/outp.c: In function 'nvif_outp_acquire_dp':
../include/linux/fortify-string.h:57:33: warning: array subscript 'unsigned char[16][0]' is partly outside array bounds of 'u8[15]' {aka 'unsigned char[15]'} [-Warray-bounds=]
57 | #define __underlying_memcpy __builtin_memcpy
| ^
...
../drivers/gpu/drm/nouveau/nvif/outp.c:140:9: note: in expansion of macro 'memcpy'
140 | memcpy(args.dp.dpcd, dpcd, sizeof(args.dp.dpcd));
| ^~~~~~
../drivers/gpu/drm/nouveau/nvif/outp.c:130:49: note: object 'dpcd' of size [0, 15]
130 | nvif_outp_acquire_dp(struct nvif_outp *outp, u8 dpcd[DP_RECEIVER_CAP_SIZE],
| ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

Fixes: 813443721331 ("drm/nouveau/disp: move DP link config into acquire")
Cc: Ben Skeggs <bskeggs@xxxxxxxxxx>
Cc: Lyude Paul <lyude@xxxxxxxxxx>
Cc: Karol Herbst <kherbst@xxxxxxxxxx>
Cc: David Airlie <airlied@xxxxxxxxx>
Cc: Daniel Vetter <daniel@xxxxxxxx>
Cc: Dave Airlie <airlied@xxxxxxxxxx>
Cc: "Gustavo A. R. Silva" <gustavo@xxxxxxxxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: nouveau@xxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
drivers/gpu/drm/nouveau/include/nvif/if0012.h | 4 +++-
drivers/gpu/drm/nouveau/nvkm/engine/disp/outp.h | 3 ++-
drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c | 2 +-
3 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/include/nvif/if0012.h b/drivers/gpu/drm/nouveau/include/nvif/if0012.h
index eb99d84eb844..16d4ad5023a3 100644
--- a/drivers/gpu/drm/nouveau/include/nvif/if0012.h
+++ b/drivers/gpu/drm/nouveau/include/nvif/if0012.h
@@ -2,6 +2,8 @@
#ifndef __NVIF_IF0012_H__
#define __NVIF_IF0012_H__

+#include <drm/display/drm_dp.h>
+
union nvif_outp_args {
struct nvif_outp_v0 {
__u8 version;
@@ -63,7 +65,7 @@ union nvif_outp_acquire_args {
__u8 hda;
__u8 mst;
__u8 pad04[4];
- __u8 dpcd[16];
+ __u8 dpcd[DP_RECEIVER_CAP_SIZE];
} dp;
};
} v0;
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/outp.h b/drivers/gpu/drm/nouveau/nvkm/engine/disp/outp.h
index b7631c1ab242..4e7f873f66e2 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/outp.h
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/outp.h
@@ -3,6 +3,7 @@
#define __NVKM_DISP_OUTP_H__
#include "priv.h"

+#include <drm/display/drm_dp.h>
#include <subdev/bios.h>
#include <subdev/bios/dcb.h>
#include <subdev/bios/dp.h>
@@ -42,7 +43,7 @@ struct nvkm_outp {
bool aux_pwr_pu;
u8 lttpr[6];
u8 lttprs;
- u8 dpcd[16];
+ u8 dpcd[DP_RECEIVER_CAP_SIZE];

struct {
int dpcd; /* -1, or index into SUPPORTED_LINK_RATES table */
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c b/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c
index 4f0ca709c85a..fc283a4a1522 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/uoutp.c
@@ -146,7 +146,7 @@ nvkm_uoutp_mthd_release(struct nvkm_outp *outp, void *argv, u32 argc)
}

static int
-nvkm_uoutp_mthd_acquire_dp(struct nvkm_outp *outp, u8 dpcd[16],
+nvkm_uoutp_mthd_acquire_dp(struct nvkm_outp *outp, u8 dpcd[DP_RECEIVER_CAP_SIZE],
u8 link_nr, u8 link_bw, bool hda, bool mst)
{
int ret;
--
2.34.1