From: Srinivasan Shanmugam <srinivasan.shanmu...@amd.com>
commit ac2140449184a26eac99585b7f69814bd3ba8f2d upstream.
This commit addresses a potential null pointer dereference issue in the
`dcn32_acquire_idle_pipe_for_head_pipe_in_layer` function. The issue
could occur when `head_pipe` is null.
The fix adds a check to ensure `head_pipe` is not null before asserting
it. If `head_pipe` is null, the function returns NULL to prevent a
potential null pointer dereference.
Reported by smatch:
drivers/gpu/drm/amd/amdgpu/../display/dc/resource/dcn32/dcn32_resource.c:2690
dcn32_acquire_idle_pipe_for_head_pipe_in_layer() error: we previously assumed
'head_pipe' could be null (see line 2681)
Cc: Tom Chung <chiahsuan.ch...@amd.com>
Cc: Rodrigo Siqueira <rodrigo.sique...@amd.com>
Cc: Roman Li <roman...@amd.com>
Cc: Alex Hung <alex.h...@amd.com>
Cc: Aurabindo Pillai <aurabindo.pil...@amd.com>
Cc: Harry Wentland <harry.wentl...@amd.com>
Cc: Hamza Mahfooz <hamza.mahf...@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmu...@amd.com>
Reviewed-by: Tom Chung <chiahsuan.ch...@amd.com>
Signed-off-by: Alex Deucher <alexander.deuc...@amd.com>
[ Daniil: dcn32 was moved from drivers/gpu/drm/amd/display/dc to
drivers/gpu/drm/amd/display/dc/resource since commit
8b8eed05a1c6 ("drm/amd/display: Refactor resource into component directory").
The path is changed accordingly to apply the patch on 6.1.y. and 6.6.y ]
Signed-off-by: Daniil Dulov <d.du...@aladdin.ru>
---
Backport fix for CVE-2024-49918
drivers/gpu/drm/amd/display/dc/dcn32/dcn32_resource.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_resource.c
b/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_resource.c
index 1b1534ffee9f..591c3166a468 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_resource.c
@@ -2563,8 +2563,10 @@ struct pipe_ctx
*dcn32_acquire_idle_pipe_for_head_pipe_in_layer(
struct resource_context *old_ctx =
&stream->ctx->dc->current_state->res_ctx;
int head_index;
- if (!head_pipe)
+ if (!head_pipe) {
ASSERT(0);
+ return NULL;
+ }
/*
* Modified from dcn20_acquire_idle_pipe_for_layer
--
2.34.1
