| 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-2024-46850: drm/amd/display: Avoid race between dcn35_set_drr() and dc_state_destruct() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| drm/amd/display: Avoid race between dcn35_set_drr() and dc_state_destruct() |
| |
| dc_state_destruct() nulls the resource context of the DC state. The pipe |
| context passed to dcn35_set_drr() is a member of this resource context. |
| |
| If dc_state_destruct() is called parallel to the IRQ processing (which |
| calls dcn35_set_drr() at some point), we can end up using already nulled |
| function callback fields of struct stream_resource. |
| |
| The logic in dcn35_set_drr() already tries to avoid this, by checking tg |
| against NULL. But if the nulling happens exactly after the NULL check and |
| before the next access, then we get a race. |
| |
| Avoid this by copying tg first to a local variable, and then use this |
| variable for all the operations. This should work, as long as nobody |
| frees the resource pool where the timing generators live. |
| |
| (cherry picked from commit 0607a50c004798a96e62c089a4c34c220179dcb5) |
| |
| The Linux kernel CVE team has assigned CVE-2024-46850 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 6.7 with commit 06ad7e16425619a4a77154c2e85bededb3e04a4f and fixed in 6.10.11 with commit 42850927656a540428e58d370b3c1599a617bac7 |
| Issue introduced in 6.7 with commit 06ad7e16425619a4a77154c2e85bededb3e04a4f and fixed in 6.11 with commit e835d5144f5ef78e4f8828c63e2f0d61144f283a |
| |
| 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-2024-46850 |
| 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/dcn35/dcn35_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/42850927656a540428e58d370b3c1599a617bac7 |
| https://git.kernel.org/stable/c/e835d5144f5ef78e4f8828c63e2f0d61144f283a |
