| 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-2021-47471: drm: mxsfb: Fix NULL pointer dereference crash on unload |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| drm: mxsfb: Fix NULL pointer dereference crash on unload |
| |
| The mxsfb->crtc.funcs may already be NULL when unloading the driver, |
| in which case calling mxsfb_irq_disable() via drm_irq_uninstall() from |
| mxsfb_unload() leads to NULL pointer dereference. |
| |
| Since all we care about is masking the IRQ and mxsfb->base is still |
| valid, just use that to clear and mask the IRQ. |
| |
| The Linux kernel CVE team has assigned CVE-2021-47471 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.10 with commit ae1ed0093281939b80664a687689f12436c0e874 and fixed in 5.10.76 with commit f40c2281d2c0674d32ba732fee45222d76495472 |
| Issue introduced in 5.10 with commit ae1ed0093281939b80664a687689f12436c0e874 and fixed in 5.14.15 with commit b0e6db0656ddfd8bb57303c2ef61ee1c1cc694a8 |
| Issue introduced in 5.10 with commit ae1ed0093281939b80664a687689f12436c0e874 and fixed in 5.15 with commit 3cfc183052c3dbf8eae57b6c1685dab00ed3db4a |
| |
| 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-2021-47471 |
| 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/mxsfb/mxsfb_drv.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/f40c2281d2c0674d32ba732fee45222d76495472 |
| https://git.kernel.org/stable/c/b0e6db0656ddfd8bb57303c2ef61ee1c1cc694a8 |
| https://git.kernel.org/stable/c/3cfc183052c3dbf8eae57b6c1685dab00ed3db4a |
