CVE-2026-90326

In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: fix race between policy activation and blkg destruction When switching an IO scheduler on a block device, blkcg_activate_policy() allocates blkg_policy_data (pd) for all blkgs attached to the queue. However, blkcg_activate_policy() may race with concurrent blkcg deletion, leading to use-after-free and memory leak issues. The use-after-free occurs in the following race: T1 (blkcg_activate_policy): - Successfully allocates pd for blkg1 (loop0->queue, blkcgA) - Fails to allocate pd for blkg2 (loop0->queue, blkcgB) - Enters the enomem rollback path to release blkg1 resources T2 (blkcg deletion): - blkcgA is deleted concurrently - blkg1 is freed via blkg_free_workfn() - blkg1->pd is freed T1 (continued): - Rollback path accesses blkg1->pd->online after pd is freed - Triggers use-after-free In addition, blkg_free_workfn() frees pd before removing the blkg from q->blkg_list. This allows blkcg_activate_policy() to allocate a new pd for a blkg that is being destroyed, leaving the newly allocated pd unreachable when the blkg is finally freed. Fix these races by extending blkcg_mutex coverage to serialize blkcg_activate_policy() rollback and blkg destruction, ensuring pd lifecycle is synchronized with blkg list visibility.

In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: fix race between policy activation and blkg destruction When switching an IO scheduler on a block device, blkcg_activate_policy() allocates blkg_policy_data (pd) for all blkgs attached to the queue. However, blkcg_activate_policy() may race with concurrent blkcg deletion, leading to use-after-free and memory leak issues. The use-after-free occurs in the following race: T1 (blkcg_activate_policy): - Successfully allocates pd for blkg1 (loop0->queue, blkcgA) - Fails to allocate pd for blkg2 (loop0->queue, blkcgB) - Enters the enomem rollback path to release blkg1 resources T2 (blkcg deletion): - blkcgA is deleted concurrently - blkg1 is freed via blkg_free_workfn() - blkg1->pd is freed T1 (continued): - Rollback path accesses blkg1->pd->online after pd is freed - Triggers use-after-free In addition, blkg_free_workfn() frees pd before removing the blkg from q->blkg_list. This allows blkcg_activate_policy() to allocate a new pd for a blkg that is being destroyed, leaving the newly allocated pd unreachable when the blkg is finally freed. Fix these races by extending blkcg_mutex coverage to serialize blkcg_activate_policy() rollback and blkg destruction, ensuring pd lifecycle is synchronized with blkg list visibility.

In the Linux kernel, the following vulnerability has been resolved:

blk-cgroup: fix race between policy activation and blkg destruction

When switching an IO scheduler on a block device, blkcg_activate_policy() allocates blkg_policy_data (pd) for all blkgs attached to the queue. However, blkcg_activate_policy() may race with concurrent blkcg deletion, leading to use-after-free and memory leak issues.

The use-after-free occurs in the following race:

T1 (blkcg_activate_policy):

• Successfully allocates pd for blkg1 (loop0->queue, blkcgA)
• Fails to allocate pd for blkg2 (loop0->queue, blkcgB)
• Enters the enomem rollback path to release blkg1 resources

T2 (blkcg deletion):

• blkcgA is deleted concurrently
• blkg1 is freed via blkg_free_workfn()
• blkg1->pd is freed

T1 (continued):

• Rollback path accesses blkg1->pd->online after pd is freed
• Triggers use-after-free

In addition, blkg_free_workfn() frees pd before removing the blkg from q->blkg_list. This allows blkcg_activate_policy() to allocate a new pd for a blkg that is being destroyed, leaving the newly allocated pd unreachable when the blkg is finally freed.

Fix these races by extending blkcg_mutex coverage to serialize blkcg_activate_policy() rollback and blkg destruction, ensuring pd lifecycle is synchronized with blkg list visibility.

Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems:

• USB Gadget drivers;
• Memory management;
• Multiple devices driver;
• ARM64 architecture;
• EROFS file system;
• Networking core;
• eXpress Data Path;
• ARM32 architecture;
• M68K architecture;
• MIPS architecture;
• OpenRISC architecture;
• PA-RISC architecture;
• PowerPC architecture;
• RISC-V architecture;
• S390 architecture;
• User-Mode Linux (UML);
• x86 architecture;
• Block layer subsystem;
• Cryptographic API;
• Compute Acceleration Framework;
• Intel NPU Driver;
• Speakup Console Speech Driver;
• ACPI drivers;
• Serial ATA and Parallel ATA drivers;
• Auxiliary display drivers;
• Drivers core;
• Micron PCIe SSD driver;
• Null block device driver;
• Ublk userspace block driver;
• Compressed RAM block device driver;
• Bluetooth drivers;
• Bus devices;
• AMD CDX bus driver;
• Hardware random number generator core;
• Character device driver;
• TPM device driver;
• Clock framework and drivers;
• Clocksource drivers;
• CPU frequency scaling framework;
• CPU idle management framework;
• Hardware crypto device drivers;
• CXL (Compute Express Link) drivers;
• DAX dirext access to differentiated memory framework;
• DIBS (Direct Internal Buffer Sharing) drivers;
• Buffer Sharing and Synchronization framework;
• DMA engine subsystem;
• EDAC drivers;
• FireWire subsystem;
• ARM SCMI message protocol;
• ARM SCPI message protocol;
• Google firmware drivers;
• Qualcomm firmware drivers;
• FPGA Framework;
• GPIO subsystem;
• GPU drivers;
• HID subsystem;
• HSI subsystem;
• Microsoft Hyper-V drivers;
• Hardware monitoring drivers;
• CoreSight HW tracing drivers;
• I2C subsystem;
• I3C subsystem;
• IIO subsystem;
• InfiniBand drivers;
• Input Device core drivers;
• Input Device (Miscellaneous) drivers;
• Input Device (Mouse) drivers;
• On-Chip Interconnect management framework;
• IOMMU subsystem;
• Industry Pack bus drivers;
• IRQ chip drivers;
• Mailbox framework;
• Media drivers;
• MemoryStick subsystem;
• Multifunction device drivers;
• Analog Devices digital potentiometer driver;
• Broadcom VK accelerator driver;
• Fastrpc Driver;
• Amazon Nitro Secure Module driver;
• SGI GRU driver;
• MMC subsystem;
• MTD block device drivers;
• Network drivers;
• Ethernet bonding driver;
• Mellanox network drivers;
• Microsoft Azure Network Adapter (MANA) driver;
• STMicroelectronics network drivers;
• Texas Instruments network drivers;
• MediaTek network drivers;
• Near Field Communication (NFC) drivers;
• NTB driver;
• NVDIMM (Non-Volatile Memory Device) drivers;
• NVME drivers;
• Device tree and open firmware driver;
• Operating Performance Points (OPP) driver;
• PA-RISC drivers;
• PCI subsystem;
• Performance monitor drivers;
• PHY drivers;
• Pin controllers subsystem;
• Chrome hardware platform drivers;
• Mellanox platform drivers;
• Microsoft Surface platform drivers;
• x86 platform drivers;
• MediaTek PM domains;
• Power sequencing drivers;
• Power supply drivers;
• Powercap sysfs driver;
• PTP clock framework;
• PWM drivers;
• RapidIO drivers;
• Voltage and Current Regulator drivers;
• Remote Processor subsystem;
• MPAM driver;
• RPMSG subsystem;
• Real Time Clock drivers;
• S/390 drivers;
• SCSI subsystem;
• ASPEED SoC drivers;
• Samsung SoC drivers;
• SPI subsystem;
• small TFT LCD display modules;
• Greybus lights staging drivers;
• Media staging drivers;
• Realtek RTL8723BS SDIO drivers;
• TCM subsystem;
• Trusted Execution Environment drivers;
• Thermal drivers;
• Thunderbolt and USB4 drivers;
• TTY drivers;
• UFS subsystem;
• Userspace I/O drivers;
• USB DSL drivers;
• Cypress C67X00 USB…

Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems:

• USB Gadget drivers;
• Memory management;
• Multiple devices driver;
• ARM64 architecture;
• EROFS file system;
• Networking core;
• eXpress Data Path;
• ARM32 architecture;
• M68K architecture;
• MIPS architecture;
• OpenRISC architecture;
• PA-RISC architecture;
• PowerPC architecture;
• RISC-V architecture;
• S390 architecture;
• User-Mode Linux (UML);
• x86 architecture;
• Block layer subsystem;
• Cryptographic API;
• Compute Acceleration Framework;
• Intel NPU Driver;
• Speakup Console Speech Driver;
• ACPI drivers;
• Serial ATA and Parallel ATA drivers;
• Auxiliary display drivers;
• Drivers core;
• Micron PCIe SSD driver;
• Null block device driver;
• Ublk userspace block driver;
• Compressed RAM block device driver;
• Bluetooth drivers;
• Bus devices;
• AMD CDX bus driver;
• Hardware random number generator core;
• Character device driver;
• TPM device driver;
• Clock framework and drivers;
• Clocksource drivers;
• CPU frequency scaling framework;
• CPU idle management framework;
• Hardware crypto device drivers;
• CXL (Compute Express Link) drivers;
• DAX dirext access to differentiated memory framework;
• DIBS (Direct Internal Buffer Sharing) drivers;
• Buffer Sharing and Synchronization framework;
• DMA engine subsystem;
• EDAC drivers;
• FireWire subsystem;
• ARM SCMI message protocol;
• ARM SCPI message protocol;
• Google firmware drivers;
• Qualcomm firmware drivers;
• FPGA Framework;
• GPIO subsystem;
• GPU drivers;
• HID subsystem;
• HSI subsystem;
• Microsoft Hyper-V drivers;
• Hardware monitoring drivers;
• CoreSight HW tracing drivers;
• I2C subsystem;
• I3C subsystem;
• IIO subsystem;
• InfiniBand drivers;
• Input Device core drivers;
• Input Device (Miscellaneous) drivers;
• Input Device (Mouse) drivers;
• On-Chip Interconnect management framework;
• IOMMU subsystem;
• Industry Pack bus drivers;
• IRQ chip drivers;
• Mailbox framework;
• Media drivers;
• MemoryStick subsystem;
• Multifunction device drivers;
• Analog Devices digital potentiometer driver;
• Broadcom VK accelerator driver;
• Fastrpc Driver;
• Amazon Nitro Secure Module driver;
• SGI GRU driver;
• MMC subsystem;
• MTD block device drivers;
• Network drivers;
• Ethernet bonding driver;
• Mellanox network drivers;
• Microsoft Azure Network Adapter (MANA) driver;
• STMicroelectronics network drivers;
• Texas Instruments network drivers;
• MediaTek network drivers;
• Near Field Communication (NFC) drivers;
• NTB driver;
• NVDIMM (Non-Volatile Memory Device) drivers;
• NVME drivers;
• Device tree and open firmware driver;
• Operating Performance Points (OPP) driver;
• PA-RISC drivers;
• PCI subsystem;
• Performance monitor drivers;
• PHY drivers;
• Pin controllers subsystem;
• Chrome hardware platform drivers;
• Mellanox platform drivers;
• Microsoft Surface platform drivers;
• x86 platform drivers;
• MediaTek PM domains;
• Power sequencing drivers;
• Power supply drivers;
• Powercap sysfs driver;
• PTP clock framework;
• PWM drivers;
• RapidIO drivers;
• Voltage and Current Regulator drivers;
• Remote Processor subsystem;
• MPAM driver;
• RPMSG subsystem;
• Real Time Clock drivers;
• S/390 drivers;
• SCSI subsystem;
• ASPEED SoC drivers;
• Samsung SoC drivers;
• SPI subsystem;
• small TFT LCD display modules;
• Greybus lights staging drivers;
• Media staging drivers;
• Realtek RTL8723BS SDIO drivers;
• TCM subsystem;
• Trusted Execution Environment drivers;
• Thermal drivers;
• Thunderbolt and USB4 drivers;
• TTY drivers;
• UFS subsystem;
• Userspace I/O drivers;
• USB DSL drivers;
• Cypress C67X00 USB…