[SRU][F][PATCH 1/1] drm/amdgpu: Fix out-of-bounds read of df_v1_7_channel_number

[Bethany Jamison]

From: Ma Jun <Jun.Ma2 at amd.com>

[ Upstream commit d768394fa99467bcf2703bde74ddc96eeb0b71fa ]

Check the fb_channel_number range to avoid the array out-of-bounds
read error

Signed-off-by: Ma Jun <Jun.Ma2 at amd.com>
Reviewed-by: Tim Huang <Tim.Huang at amd.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Sasha Levin <sashal at kernel.org>
(backported from commit 725b728cc0c8c5fafdfb51cb0937870d33a40fa4 linux-5.10.y)
[bjamison: kept 'df_funcs' instead of backporting commit bdf84a80e0ce5f60f4f41
and using 'df.funcs']
CVE-2024-46724
Signed-off-by: Bethany Jamison <bethany.jamison at canonical.com>
---
 drivers/gpu/drm/amd/amdgpu/df_v1_7.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/df_v1_7.c b/drivers/gpu/drm/amd/amdgpu/df_v1_7.c
index 844c038682485..8f80fc5712268 100644
--- a/drivers/gpu/drm/amd/amdgpu/df_v1_7.c
+++ b/drivers/gpu/drm/amd/amdgpu/df_v1_7.c
@@ -63,6 +63,8 @@ static u32 df_v1_7_get_hbm_channel_number(struct amdgpu_device *adev)
 	int fb_channel_number;
 
 	fb_channel_number = adev->df_funcs->get_fb_channel_number(adev);
+	if (fb_channel_number >= ARRAY_SIZE(df_v1_7_channel_number))
+		fb_channel_number = 0;
 
 	return df_v1_7_channel_number[fb_channel_number];
 }
-- 
2.34.1