| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2024-47720: drm/amd/display: Add null check for set_output_gamma in dcn30_set_output_transfer_func |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| drm/amd/display: Add null check for set_output_gamma in dcn30_set_output_transfer_func |
| |
| This commit adds a null check for the set_output_gamma function pointer |
| in the dcn30_set_output_transfer_func function. Previously, |
| set_output_gamma was being checked for nullity at line 386, but then it |
| was being dereferenced without any nullity check at line 401. This |
| could potentially lead to a null pointer dereference error if |
| set_output_gamma is indeed null. |
| |
| To fix this, we now ensure that set_output_gamma is not null before |
| dereferencing it. We do this by adding a nullity check for |
| set_output_gamma before the call to set_output_gamma at line 401. If |
| set_output_gamma is null, we log an error message and do not call the |
| function. |
| |
| This fix prevents a potential null pointer dereference error. |
| |
| drivers/gpu/drm/amd/amdgpu/../display/dc/hwss/dcn30/dcn30_hwseq.c:401 dcn30_set_output_transfer_func() |
| error: we previously assumed 'mpc->funcs->set_output_gamma' could be null (see line 386) |
| |
| drivers/gpu/drm/amd/amdgpu/../display/dc/hwss/dcn30/dcn30_hwseq.c |
| 373 bool dcn30_set_output_transfer_func(struct dc *dc, |
| 374 struct pipe_ctx *pipe_ctx, |
| 375 const struct dc_stream_state *stream) |
| 376 { |
| 377 int mpcc_id = pipe_ctx->plane_res.hubp->inst; |
| 378 struct mpc *mpc = pipe_ctx->stream_res.opp->ctx->dc->res_pool->mpc; |
| 379 const struct pwl_params *params = NULL; |
| 380 bool ret = false; |
| 381 |
| 382 /* program OGAM or 3DLUT only for the top pipe*/ |
| 383 if (pipe_ctx->top_pipe == NULL) { |
| 384 /*program rmu shaper and 3dlut in MPC*/ |
| 385 ret = dcn30_set_mpc_shaper_3dlut(pipe_ctx, stream); |
| 386 if (ret == false && mpc->funcs->set_output_gamma) { |
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ If this is NULL |
| |
| 387 if (stream->out_transfer_func.type == TF_TYPE_HWPWL) |
| 388 params = &stream->out_transfer_func.pwl; |
| 389 else if (pipe_ctx->stream->out_transfer_func.type == |
| 390 TF_TYPE_DISTRIBUTED_POINTS && |
| 391 cm3_helper_translate_curve_to_hw_format( |
| 392 &stream->out_transfer_func, |
| 393 &mpc->blender_params, false)) |
| 394 params = &mpc->blender_params; |
| 395 /* there are no ROM LUTs in OUTGAM */ |
| 396 if (stream->out_transfer_func.type == TF_TYPE_PREDEFINED) |
| 397 BREAK_TO_DEBUGGER(); |
| 398 } |
| 399 } |
| 400 |
| --> 401 mpc->funcs->set_output_gamma(mpc, mpcc_id, params); |
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Then it will crash |
| |
| 402 return ret; |
| 403 } |
| |
| The Linux kernel CVE team has assigned CVE-2024-47720 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.9 with commit d99f13878d6f9c286b13860d8bf0b4db9ffb189a and fixed in 5.15.168 with commit 44948d3cb943602ba4a0b5ed3c91ae0525838fb1 |
| Issue introduced in 5.9 with commit d99f13878d6f9c286b13860d8bf0b4db9ffb189a and fixed in 6.1.113 with commit 64886a4e6f1dce843c0889505cf0673b5211e16a |
| Issue introduced in 5.9 with commit d99f13878d6f9c286b13860d8bf0b4db9ffb189a and fixed in 6.6.54 with commit ddf9ff244d704e1903533f7be377615ed34b83e7 |
| Issue introduced in 5.9 with commit d99f13878d6f9c286b13860d8bf0b4db9ffb189a and fixed in 6.10.13 with commit 84edd5a3f5fa6aafa4afcaf9f101f46426c620c9 |
| Issue introduced in 5.9 with commit d99f13878d6f9c286b13860d8bf0b4db9ffb189a and fixed in 6.11.2 with commit 72ee32d0907364104fbcf4f68dd5ae63cd8eae9e |
| Issue introduced in 5.9 with commit d99f13878d6f9c286b13860d8bf0b4db9ffb189a and fixed in 6.12 with commit 08ae395ea22fb3d9b318c8bde28c0dfd2f5fa4d2 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2024-47720 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| drivers/gpu/drm/amd/display/dc/hwss/dcn30/dcn30_hwseq.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/44948d3cb943602ba4a0b5ed3c91ae0525838fb1 |
| https://git.kernel.org/stable/c/64886a4e6f1dce843c0889505cf0673b5211e16a |
| https://git.kernel.org/stable/c/ddf9ff244d704e1903533f7be377615ed34b83e7 |
| https://git.kernel.org/stable/c/84edd5a3f5fa6aafa4afcaf9f101f46426c620c9 |
| https://git.kernel.org/stable/c/72ee32d0907364104fbcf4f68dd5ae63cd8eae9e |
| https://git.kernel.org/stable/c/08ae395ea22fb3d9b318c8bde28c0dfd2f5fa4d2 |
