CVE-2026-80704

In the Linux kernel, the following vulnerability has been resolved:

drm/amd/display: use proper context for logging

The same as the rest of the code, get_ss_info_from_atombios() uses

calc_pll_cs->ctx->logger for logging. But calc_pll_cs->ctx is

initialized only later in calc_pll_max_vco_construct(). Therefore, any

output using DC_LOG_SYNC() leads to a NULL pointer deference in

get_ss_info_from_atombios().

According to Sashiko, the very same problem exists in

dce112_get_pix_clk_dividers() and dcn3_get_pix_clk_dividers() too.

To avoid accessing the NULL context, use clk_src->base.ctx->logger

everywhere. That context in base is initialized earlier in

dce110_clk_src_construct() and dce112_clk_src_construct(). Before

get_ss_info_from_atombios() or Sashiko's get_pix_clk_dividers functions

above are actually called. This is done by redefining DC_LOGGER to

CTX->logger.

Before:

dce110_clk_src_construct() did:

-> sets clk_src->base.ctx = ctx;

-> ss_info_from_atombios_create()

-> get_ss_info_from_atombios() <- uses calc_pll_cs->ctx # BOOM

-> calc_pll_max_vco_construct() <- sets calc_pll_cs->ctx

After:

dce110_clk_src_construct() does:

-> sets clk_src->base.ctx = ctx;

-> ss_info_from_atombios_create()

-> get_ss_info_from_atombios() <- uses clk_src->base.ctx

(cherry picked from commit 6f16fcbb0c46a87e3d9685407e906573d60104b0)