CVE-2026-80527 — ceph: fix hanging __ceph_get_caps() with stale mds_wanted

Affected: Linux

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

ceph: fix hanging __ceph_get_caps() with stale mds_wanted

A reader can hang forever in __ceph_get_caps() when the client no longer holds `FILE_RD`, but local cap state still says that the capability is already wanted (via `mds_wanted`).

One way to trigger this is through MDS cap revocation. If another client performs a conflicting operation, the MDS can revoke `FILE_RD` from the reader; the next read then has to reacquire `FILE_RD`. If the cap update that should request `FILE_RD` never reaches the MDS after `cap->mds_wanted` was raised, the reader is left holding only non-file caps while local `mds_wanted` still includes the file read caps.

In that state, try_get_cap_refs() sees `need <= mds_wanted` and returns 0, so __ceph_get_caps() just waits on `i_cap_wq`. If the cap update that was supposed to request `FILE_RD never reaches the MDS after `cap->mds_wanted was` raised, no further request is sent and the waiter can sleep indefinitely until unrelated cap traffic happens to wake it up.

The ordering issue is that `cap->mds_wanted` is updated in __prep_cap() before the `CEPH_MSG_CLIENT_CAPS message` is actually queued for send. That makes one field serve two different meanings at once: what this client wants, and what the client believes the MDS already knows it wants.

A proper fix would be to split those states and track whether a cap update is actually in flight or has been observed by the MDS. How…

USN-8886-1 — linux-nvidia-tegra vulnerabilities

Affected: Ubuntu:24.04:LTS: linux-nvidia-tegra

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: - NVDIMM (Non-Volatile Memory Device) drivers; - Handshake API; - ARM32 architecture; - ARM64 architecture; - MIPS architecture; - OpenRISC architecture; - PowerPC architecture; - S390 architecture; - x86 architecture; - Block layer subsystem; - Cryptographic API; - Intel NPU Driver; - Android drivers; - Rados block device (RBD) driver; - Bluetooth drivers; - Hardware random number generator core; - TPM device driver; - CPU frequency scaling framework; - Hardware crypto device drivers; - DMA engine subsystem; - FireWire subsystem; - Arm Firmware Framework for ARMv8-A(FFA); - GPIO subsystem; - GPU drivers; - HID subsystem; - Hardware monitoring drivers; - CoreSight HW tracing drivers; - I2C subsystem; - IIO ADC drivers; - IIO subsystem; - InfiniBand drivers; - Input Device core drivers; - Input Device (Mouse) drivers; - IOMMU subsystem; - Multiple devices driver; - Media drivers; - Multifunction device drivers; - Fastrpc Driver; - Amazon Nitro Secure Module driver; - MMC subsystem; - MTD block device drivers; - Ethernet bonding driver; - Network drivers; - Mellanox network drivers; - Texas Instruments network drivers; - NTB driver; - NVME drivers; - NVMEM (Non Volatile Memory) drivers; - Parport drivers…

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CVE-2026-80527 — ceph: fix hanging __ceph_get_caps() with stale mds_wanted

USN-8886-1 — linux-nvidia-tegra vulnerabilities