CVSS: -EPSS: 0%CPEs: 4EXPL: 0CVE-2024-50022 – device-dax: correct pgoff align in dax_set_mapping()
https://notcve.org/view.php?id=CVE-2024-50022
In the Linux kernel, the following vulnerability has been resolved: device-dax: correct pgoff align in dax_set_mapping() pgoff should be aligned using ALIGN_DOWN() instead of ALIGN(). Otherwise, vmf->address not aligned to fault_size will be aligned to the next alignment, that can result in memory failure getting the wrong address. It's a subtle situation that only can be observed in page_mapped_in_vma() after the page is page fault handled by dev_dax_huge_fault. Generally, there is little chance to perform page_mapped_in_vma in dev-dax's page unless in specific error injection to the dax device to trigger an MCE - memory-failure. In that case, page_mapped_in_vma() will be triggered to determine which task is accessing the failure address and kill that task in the end. We used self-developed dax device (which is 2M aligned mapping) , to perform error injection to random address. It turned out that error injected to non-2M-aligned address was causing endless MCE until panic. Because page_mapped_in_vma() kept resulting wrong address and the task accessing the failure address was never killed properly: [ 3783.719419] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3784.049006] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3784.049190] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3784.448042] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3784.448186] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3784.792026] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3784.792179] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3785.162502] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3785.162633] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3785.461116] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3785.461247] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3785.764730] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3785.764859] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3786.042128] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3786.042259] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3786.464293] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3786.464423] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3786.818090] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3786.818217] Memory failure: 0x200c9742: recovery action for dax page: Recovered [ 3787.085297] mce: Uncorrected hardware memory error in user-access at 200c9742380 [ 3787.085424] Memory failure: 0x200c9742: recovery action for dax page: Recovered It took us several weeks to pinpoint this problem, but we eventually used bpftrace to trace the page fault and mce address and successfully identified the issue. Joao added: ; Likely we never reproduce in production because we always pin : device-dax regions in the region align they provide (Qemu does : similarly with prealloc in hugetlb/file backed memory). • https://git.kernel.org/stable/c/b9b5777f09be84d0de472ded2253d2f5101427f2 https://git.kernel.org/stable/c/9c4198dfdca818c5ce19c764d90eabd156bbc6da https://git.kernel.org/stable/c/b822007e8db341d6f175c645ed79866db501ad86 https://git.kernel.org/stable/c/e877427d218159ac29c9326100920d24330c9ee6 https://git.kernel.org/stable/c/7fcbd9785d4c17ea533c42f20a9083a83f301fa6 •
CVSS: -EPSS: 0%CPEs: 5EXPL: 0CVE-2024-50019 – kthread: unpark only parked kthread
https://notcve.org/view.php?id=CVE-2024-50019
In the Linux kernel, the following vulnerability has been resolved: kthread: unpark only parked kthread Calling into kthread unparking unconditionally is mostly harmless when the kthread is already unparked. The wake up is then simply ignored because the target is not in TASK_PARKED state. However if the kthread is per CPU, the wake up is preceded by a call to kthread_bind() which expects the task to be inactive and in TASK_PARKED state, which obviously isn't the case if it is unparked. As a result, calling kthread_stop() on an unparked per-cpu kthread triggers such a warning: WARNING: CPU: 0 PID: 11 at kernel/kthread.c:525 __kthread_bind_mask kernel/kthread.c:525 <TASK> kthread_stop+0x17a/0x630 kernel/kthread.c:707 destroy_workqueue+0x136/0xc40 kernel/workqueue.c:5810 wg_destruct+0x1e2/0x2e0 drivers/net/wireguard/device.c:257 netdev_run_todo+0xe1a/0x1000 net/core/dev.c:10693 default_device_exit_batch+0xa14/0xa90 net/core/dev.c:11769 ops_exit_list net/core/net_namespace.c:178 [inline] cleanup_net+0x89d/0xcc0 net/core/net_namespace.c:640 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> Fix this with skipping unecessary unparking while stopping a kthread. • https://git.kernel.org/stable/c/5c25b5ff89f004c30b04759dc34ace8585a4085f https://git.kernel.org/stable/c/40a6e660d2a3a7a5cb99f0b8ff4fb41bad039f68 https://git.kernel.org/stable/c/8608196a155cb6cfae04d96b10a2652d0327e33f https://git.kernel.org/stable/c/19a5029981c87c2ad0845e713837faa88f5d8e2b https://git.kernel.org/stable/c/cda5423c1a1c906062ef235c940f249b97d9d135 https://git.kernel.org/stable/c/214e01ad4ed7158cab66498810094fac5d09b218 •
CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2024-50018 – net: napi: Prevent overflow of napi_defer_hard_irqs
https://notcve.org/view.php?id=CVE-2024-50018
In the Linux kernel, the following vulnerability has been resolved: net: napi: Prevent overflow of napi_defer_hard_irqs In commit 6f8b12d661d0 ("net: napi: add hard irqs deferral feature") napi_defer_irqs was added to net_device and napi_defer_irqs_count was added to napi_struct, both as type int. This value never goes below zero, so there is not reason for it to be a signed int. Change the type for both from int to u32, and add an overflow check to sysfs to limit the value to S32_MAX. The limit of S32_MAX was chosen because the practical limit before this patch was S32_MAX (anything larger was an overflow) and thus there are no behavioral changes introduced. If the extra bit is needed in the future, the limit can be raised. Before this patch: $ sudo bash -c 'echo 2147483649 > /sys/class/net/eth4/napi_defer_hard_irqs' $ cat /sys/class/net/eth4/napi_defer_hard_irqs -2147483647 After this patch: $ sudo bash -c 'echo 2147483649 > /sys/class/net/eth4/napi_defer_hard_irqs' bash: line 0: echo: write error: Numerical result out of range Similarly, /sys/class/net/XXXXX/tx_queue_len is defined as unsigned: include/linux/netdevice.h: unsigned int tx_queue_len; And has an overflow check: dev_change_tx_queue_len(..., unsigned long new_len): if (new_len != (unsigned int)new_len) return -ERANGE; • https://git.kernel.org/stable/c/d694ad8b7e5004df86ecd415cb2320d543723672 https://git.kernel.org/stable/c/5e753b743d3b38a3e10be666c32c5434423d0093 https://git.kernel.org/stable/c/08062af0a52107a243f7608fd972edb54ca5b7f8 •
CVSS: -EPSS: 0%CPEs: 3EXPL: 0CVE-2024-50017 – x86/mm/ident_map: Use gbpages only where full GB page should be mapped.
https://notcve.org/view.php?id=CVE-2024-50017
In the Linux kernel, the following vulnerability has been resolved: x86/mm/ident_map: Use gbpages only where full GB page should be mapped. When ident_pud_init() uses only GB pages to create identity maps, large ranges of addresses not actually requested can be included in the resulting table; a 4K request will map a full GB. This can include a lot of extra address space past that requested, including areas marked reserved by the BIOS. That allows processor speculation into reserved regions, that on UV systems can cause system halts. Only use GB pages when map creation requests include the full GB page of space. Fall back to using smaller 2M pages when only portions of a GB page are included in the request. No attempt is made to coalesce mapping requests. If a request requires a map entry at the 2M (pmd) level, subsequent mapping requests within the same 1G region will also be at the pmd level, even if adjacent or overlapping such requests could have been combined to map a full GB page. Existing usage starts with larger regions and then adds smaller regions, so this should not have any great consequence. • https://git.kernel.org/stable/c/d80a99892f7a992d103138fa4636b2c33abd6740 https://git.kernel.org/stable/c/a23823098ab2c277c14fc110b97d8d5c83597195 https://git.kernel.org/stable/c/cc31744a294584a36bf764a0ffa3255a8e69f036 •
CVSS: -EPSS: 0%CPEs: 4EXPL: 0CVE-2024-50016 – drm/amd/display: Avoid overflow assignment in link_dp_cts
https://notcve.org/view.php?id=CVE-2024-50016
In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Avoid overflow assignment in link_dp_cts sampling_rate is an uint8_t but is assigned an unsigned int, and thus it can overflow. As a result, sampling_rate is changed to uint32_t. Similarly, LINK_QUAL_PATTERN_SET has a size of 2 bits, and it should only be assigned to a value less or equal than 4. This fixes 2 INTEGER_OVERFLOW issues reported by Coverity. • https://git.kernel.org/stable/c/a1495acc6234fa79b775599d3f49009afd53299f https://git.kernel.org/stable/c/26ced9d86240868f5b41708ceee02e6ec2924498 https://git.kernel.org/stable/c/adeed800bc30ef718478b28c08f79231e5980e3d https://git.kernel.org/stable/c/a15268787b79fd183dd526cc16bec9af4f4e49a1 •