| 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-2024-50196: pinctrl: ocelot: fix system hang on level based interrupts |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| pinctrl: ocelot: fix system hang on level based interrupts |
| |
| The current implementation only calls chained_irq_enter() and |
| chained_irq_exit() if it detects pending interrupts. |
| |
| ``` |
| for (i = 0; i < info->stride; i++) { |
| uregmap_read(info->map, id_reg + 4 * i, ®); |
| if (!reg) |
| continue; |
| |
| chained_irq_enter(parent_chip, desc); |
| ``` |
| |
| However, in case of GPIO pin configured in level mode and the parent |
| controller configured in edge mode, GPIO interrupt might be lowered by the |
| hardware. In the result, if the interrupt is short enough, the parent |
| interrupt is still pending while the GPIO interrupt is cleared; |
| chained_irq_enter() never gets called and the system hangs trying to |
| service the parent interrupt. |
| |
| Moving chained_irq_enter() and chained_irq_exit() outside the for loop |
| ensures that they are called even when GPIO interrupt is lowered by the |
| hardware. |
| |
| The similar code with chained_irq_enter() / chained_irq_exit() functions |
| wrapping interrupt checking loop may be found in many other drivers: |
| ``` |
| grep -r -A 10 chained_irq_enter drivers/pinctrl |
| ``` |
| |
| The Linux kernel CVE team has assigned CVE-2024-50196 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.16 with commit ce8dc0943357a5d10b05dcf0556b537c1d7b8b1f and fixed in 5.15.169 with commit 655f5d4662b958122b260be05aa6dfdf8768efe6 |
| Issue introduced in 4.16 with commit ce8dc0943357a5d10b05dcf0556b537c1d7b8b1f and fixed in 6.1.114 with commit 4a81800ef05bea5a9896f199677f7b7f5020776a |
| Issue introduced in 4.16 with commit ce8dc0943357a5d10b05dcf0556b537c1d7b8b1f and fixed in 6.6.58 with commit 20728e86289ab463b99b7ab4425515bd26aba417 |
| Issue introduced in 4.16 with commit ce8dc0943357a5d10b05dcf0556b537c1d7b8b1f and fixed in 6.11.5 with commit dcbe9954634807ec54e22bde278b5b269f921381 |
| Issue introduced in 4.16 with commit ce8dc0943357a5d10b05dcf0556b537c1d7b8b1f and fixed in 6.12 with commit 93b8ddc54507a227087c60a0013ed833b6ae7d3c |
| |
| 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-2024-50196 |
| 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/pinctrl/pinctrl-ocelot.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/655f5d4662b958122b260be05aa6dfdf8768efe6 |
| https://git.kernel.org/stable/c/4a81800ef05bea5a9896f199677f7b7f5020776a |
| https://git.kernel.org/stable/c/20728e86289ab463b99b7ab4425515bd26aba417 |
| https://git.kernel.org/stable/c/dcbe9954634807ec54e22bde278b5b269f921381 |
| https://git.kernel.org/stable/c/93b8ddc54507a227087c60a0013ed833b6ae7d3c |
