An update for kernel is now available for openEuler-22.03-LTS-SP3 Security Advisory openeuler-release@openeuler.org openEuler release SIG openEuler-HotPatchSA-2025-1005 Final 1.0 1.0 2025-01-24 Initial 2025-01-24 2025-01-24 openEuler HotPatchSA Tool V1.0 2025-01-24 kernel security update An update for kernel is now available for openEuler-22.03-LTS-SP3 The Linux Kernel, the operating system core itself. Security Fix(es): In the Linux kernel, the following vulnerability has been resolved: gpiolib: cdev: Fix use after free in lineinfo_changed_notify The use-after-free issue occurs as follows: when the GPIO chip device file is being closed by invoking gpio_chrdev_release(), watched_lines is freed by bitmap_free(), but the unregistration of lineinfo_changed_nb notifier chain failed due to waiting write rwsem. Additionally, one of the GPIO chip's lines is also in the release process and holds the notifier chain's read rwsem. Consequently, a race condition leads to the use-after-free of watched_lines. Here is the typical stack when issue happened: [free] gpio_chrdev_release() --> bitmap_free(cdev->watched_lines) <-- freed --> blocking_notifier_chain_unregister() --> down_write(&nh->rwsem) <-- waiting rwsem --> __down_write_common() --> rwsem_down_write_slowpath() --> schedule_preempt_disabled() --> schedule() [use] st54spi_gpio_dev_release() --> gpio_free() --> gpiod_free() --> gpiod_free_commit() --> gpiod_line_state_notify() --> blocking_notifier_call_chain() --> down_read(&nh->rwsem); <-- held rwsem --> notifier_call_chain() --> lineinfo_changed_notify() --> test_bit(xxxx, cdev->watched_lines) <-- use after free The side effect of the use-after-free issue is that a GPIO line event is being generated for userspace where it shouldn't. However, since the chrdev is being closed, userspace won't have the chance to read that event anyway. To fix the issue, call the bitmap_free() function after the unregistration of lineinfo_changed_nb notifier chain.(CVE-2024-36899) An update for kernel is now available for openEuler-22.03-LTS-SP3. openEuler Security has rated this update as having a security impact of high. A Common Vunlnerability Scoring System(CVSS)base score,which gives a detailed severity rating, is available for each vulnerability from the CVElink(s) in the References section. High kernel https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-HotPatchSA-2025-1005 https://www.openeuler.org/en/security/cve/detail/?cveId=CVE-2024-36899 https://nvd.nist.gov/vuln/detail/CVE-2024-36899 openEuler-22.03-LTS-SP3 kernel-5.10.0-182.0.0.95.oe2203sp3-ACC-1-8.src.rpm patch-kernel-5.10.0-182.0.0.95.oe2203sp3-ACC-1-8.x86_64.rpm patch-kernel-5.10.0-182.0.0.95.oe2203sp3-ACC-1-8.aarch64.rpm In the Linux kernel, the following vulnerability has been resolved: gpiolib: cdev: Fix use after free in lineinfo_changed_notify The use-after-free issue occurs as follows: when the GPIO chip device file is being closed by invoking gpio_chrdev_release(), watched_lines is freed by bitmap_free(), but the unregistration of lineinfo_changed_nb notifier chain failed due to waiting write rwsem. Additionally, one of the GPIO chip's lines is also in the release process and holds the notifier chain's read rwsem. Consequently, a race condition leads to the use-after-free of watched_lines. Here is the typical stack when issue happened: [free] gpio_chrdev_release() --> bitmap_free(cdev->watched_lines) <-- freed --> blocking_notifier_chain_unregister() --> down_write(&nh->rwsem) <-- waiting rwsem --> __down_write_common() --> rwsem_down_write_slowpath() --> schedule_preempt_disabled() --> schedule() [use] st54spi_gpio_dev_release() --> gpio_free() --> gpiod_free() --> gpiod_free_commit() --> gpiod_line_state_notify() --> blocking_notifier_call_chain() --> down_read(&nh->rwsem); <-- held rwsem --> notifier_call_chain() --> lineinfo_changed_notify() --> test_bit(xxxx, cdev->watched_lines) <-- use after free The side effect of the use-after-free issue is that a GPIO line event is being generated for userspace where it shouldn't. However, since the chrdev is being closed, userspace won't have the chance to read that event anyway. To fix the issue, call the bitmap_free() function after the unregistration of lineinfo_changed_nb notifier chain. 2025-01-24 CVE-2024-36899 openEuler-22.03-LTS-SP3 High 7.0 AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H kernel security update 2025-01-24 https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-HotPatchSA-2025-1005