Affected: Linux

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

RDMA/mlx5: Fix a race for an ODP MR which leads to CQE with error

This patch addresses a race condition for an ODP MR that can result in a CQE with an error on the UMR QP.

During the __mlx5_ib_dereg_mr() flow, the following sequence of calls occurs:

mlx5_revoke_mr() mlx5r_umr_revoke_mr() mlx5r_umr_post_send_wait()

At this point, the lkey is freed from the hardware's perspective.

However, concurrently, mlx5_ib_invalidate_range() might be triggered by another task attempting to invalidate a range for the same freed lkey.

This task will: - Acquire the umem_odp->umem_mutex lock. - Call mlx5r_umr_update_xlt() on the UMR QP. - Since the lkey has already been freed, this can lead to a CQE error, causing the UMR QP to enter an error state [1].

To resolve this race condition, the umem_odp->umem_mutex lock is now also acquired as part of the mlx5_revoke_mr() scope. Upon successful revoke, we set umem_odp->private which points to that MR to NULL, preventing any further invalidation attempts on its lkey.

[1] From dmesg:

infiniband rocep8s0f0: dump_cqe:277:(pid 0): WC error: 6, Message: memory bind operation error cqe_dump: 00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 cqe_dump: 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 cqe_dump: 00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 cqe_dump: 00000030: 00 00 00 00 08 00 78 06 25 00 11 b9 00 0e dd d2

WA…

Affected: Ubuntu:24.04:LTS: linux-azure-6.11, Ubuntu:24.04:LTS: linux-gcp-6.11, Ubuntu:24.04:LTS: linux-hwe-6.11, Ubuntu:24.04:LTS: linux-oem-6.11

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: - ARM64 architecture; - PowerPC architecture; - x86 architecture; - Block layer subsystem; - Serial ATA and Parallel ATA drivers; - Drivers core; - Network block device driver; - Bluetooth drivers; - Character device driver; - TPM device driver; - Clock framework and drivers; - Hardware crypto device drivers; - FireWire subsystem; - EFI core; - Qualcomm firmware drivers; - GPIO subsystem; - GPU drivers; - HID subsystem; - I2C subsystem; - I3C subsystem; - InfiniBand drivers; - Input Device (Mouse) drivers; - IOMMU subsystem; - Multiple devices driver; - Media drivers; - NVIDIA Tegra memory controller driver; - Fastrpc Driver; - Network drivers; - Operating Performance Points (OPP) driver; - PCI subsystem; - x86 platform drivers; - PPS (Pulse Per Second) driver; - PTP clock framework; - Remote Processor subsystem; - Real Time Clock drivers; - S/390 drivers; - SCSI subsystem; - QCOM SoC drivers; - SPI subsystem; - Media staging drivers; - Trusted Execution Environment drivers; - TTY drivers; - UFS subsystem; - USB Device Class drivers; - USB core drivers; - USB Gadget drivers; - USB Host Controller drivers; - Framebuffer layer; - File systems infrastructure; - BTRFS file system; - Ceph distributed fi…