DEBIAN-CVE-2026-99224: High severity debian/linux vulnerability

In the Linux kernel, the following vulnerability has been resolved: keys: Protect the type name while describing a key keyctldescribekey() must keep the key type's name alive until kasprintf() has consumed it. The retained key reference keeps the key and its description alive, but does not pin the module providing its type. The name is passed to kasprintf() without holding key->sem. kvasprintf() uses the saved name pointer in two formatting passes, with a GFPKERNEL allocation between them. With AFRXRPC=m, a task that passes View permission before type retirement can overlap a privileged module unload in this order: 1. KEYCTLDESCRIBE looks up the key, saves key->type->name in the kasprintf() arguments and completes the first formatting pass. 2. While the formatter is delayed before its second pass, afrxrpcexit() calls unregisterkeytype(), which removes the type from the registry and waits for keygckeytype(). 3. The collector takes key->sem for writing, retypes the retained key to keytypedead and completes retirement. Unregistration and module exit return, allowing freemodule() to release the type and name. 4. The formatter resumes its second pass and reads the saved name from released module storage, which can fault in string(). Hold key->sem for reading across kasprintf(). The collector then cannot retype the key or complete retirement until both formatting passes have finished. If retirement wins the lock first, formatting uses the core keytypedead name instead. Release the semaphore immediately after kasprintf(), including on allocation failure, before copying to userspace. Oops report as below: BUG: unable to handle page fault for address: fffffbfff8054794 #PF: supervisor read access in kernel mode #PF: errorcode(0x0000) - not-present page RIP: 0010:string+0x23f/0x470 Call Trace: vsnprintf+0x330/0x1110