Linux Kernel 6.11-6.12.76 - Unprivileged Local Denial of Service via fremovexattr Error Path File Reference Leak
In the Linux kernel, the following vulnerability has been resolved:
fs/xattr: missing fdput() in fremovexattr error path
In the Linux kernel, the fremovexattr() syscall calls fdget() to acquire a
file reference but returns early without calling fdput() when
strncpy_from_user() fails on the name argument. In multi-threaded processes
where fdget() takes the slow path, this permanently leaks one
file reference per call, pinning the struct file and associated kernel
objects in memory. An unprivileged local user can exploit this to cause
kernel memory exhaustion. The issue was inadvertently fixed by commit
a71874379ec8 ("xattr: switch to CLASS(fd)").