[PATCH 4.19 056/105] drm/amd/dc/dce120: Fix audio register mapping, stop triggering KASAN

Greg Kroah-Hartman
2022-12-05T19:20:19Z

From: Lyude Paul <lyude@redhat.com>

commit 44035ec2fde1114254ee465f9ba3bb246b0b6283 upstream.

There's been a very long running bug that seems to have been neglected for
a while, where amdgpu consistently triggers a KASAN error at start:

BUG: KASAN: global-out-of-bounds in read_indirect_azalia_reg+0x1d4/0x2a0 [amdgpu]
Read of size 4 at addr ffffffffc2274b28 by task modprobe/1889

After digging through amd's rather creative method for accessing registers,
I eventually discovered the problem likely has to do with the fact that on
my dce120 GPU there are supposedly 7 sets of audio registers. But we only
define a register mapping for 6 sets.

So, fix this and fix the KASAN warning finally.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: stable@vger.kernel.org
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpu/drm/amd/display/dc/dce120/dce120_resource.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/amd/display/dc/dce120/dce120_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dce120/dce120_resource.c
@@ -324,7 +324,8 @@ static const struct dce_audio_registers
audio_regs(2),
audio_regs(3),
audio_regs(4),
- audio_regs(5)
+ audio_regs(5),
+ audio_regs(6),
};

#define DCE120_AUD_COMMON_MASK_SH_LIST(mask_sh)\