| 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-2022-49506: drm/mediatek: Add vblank register/unregister callback functions |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| drm/mediatek: Add vblank register/unregister callback functions |
| |
| We encountered a kernel panic issue that callback data will be NULL when |
| it's using in ovl irq handler. There is a timing issue between |
| mtk_disp_ovl_irq_handler() and mtk_ovl_disable_vblank(). |
| |
| To resolve this issue, we use the flow to register/unregister vblank cb: |
| - Register callback function and callback data when crtc creates. |
| - Unregister callback function and callback data when crtc destroies. |
| |
| With this solution, we can assure callback data will not be NULL when |
| vblank is disable. |
| |
| The Linux kernel CVE team has assigned CVE-2022-49506 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.12 with commit 9b0704988b151824a51133dc4c921f4273c5d839 and fixed in 5.15.54 with commit 8a2dbdeccef6de47565638abdf3c25f41cdffc37 |
| Issue introduced in 5.12 with commit 9b0704988b151824a51133dc4c921f4273c5d839 and fixed in 5.17.14 with commit 8a265d9838bc3c63579002d55c2b2c655c4f8f26 |
| Issue introduced in 5.12 with commit 9b0704988b151824a51133dc4c921f4273c5d839 and fixed in 5.18.3 with commit 3a4027b5971fe2a94e32754f007d9d3c12c68ad1 |
| Issue introduced in 5.12 with commit 9b0704988b151824a51133dc4c921f4273c5d839 and fixed in 5.19 with commit b74d921b900b6ce38c6247c0a1c86be9f3746493 |
| |
| 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-2022-49506 |
| 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/mediatek/mtk_disp_drv.h |
| drivers/gpu/drm/mediatek/mtk_disp_ovl.c |
| drivers/gpu/drm/mediatek/mtk_disp_rdma.c |
| drivers/gpu/drm/mediatek/mtk_drm_crtc.c |
| drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c |
| drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h |
| |
| |
| 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/8a2dbdeccef6de47565638abdf3c25f41cdffc37 |
| https://git.kernel.org/stable/c/8a265d9838bc3c63579002d55c2b2c655c4f8f26 |
| https://git.kernel.org/stable/c/3a4027b5971fe2a94e32754f007d9d3c12c68ad1 |
| https://git.kernel.org/stable/c/b74d921b900b6ce38c6247c0a1c86be9f3746493 |
