CVE-2021-47124

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> io_uring: fix link timeout refs<br /> <br /> WARNING: CPU: 0 PID: 10242 at lib/refcount.c:28 refcount_warn_saturate+0x15b/0x1a0 lib/refcount.c:28<br /> RIP: 0010:refcount_warn_saturate+0x15b/0x1a0 lib/refcount.c:28<br /> Call Trace:<br /> __refcount_sub_and_test include/linux/refcount.h:283 [inline]<br /> __refcount_dec_and_test include/linux/refcount.h:315 [inline]<br /> refcount_dec_and_test include/linux/refcount.h:333 [inline]<br /> io_put_req fs/io_uring.c:2140 [inline]<br /> io_queue_linked_timeout fs/io_uring.c:6300 [inline]<br /> __io_queue_sqe+0xbef/0xec0 fs/io_uring.c:6354<br /> io_submit_sqe fs/io_uring.c:6534 [inline]<br /> io_submit_sqes+0x2bbd/0x7c50 fs/io_uring.c:6660<br /> __do_sys_io_uring_enter fs/io_uring.c:9240 [inline]<br /> __se_sys_io_uring_enter+0x256/0x1d60 fs/io_uring.c:9182<br /> <br /> io_link_timeout_fn() should put only one reference of the linked timeout<br /> request, however in case of racing with the master request&amp;#39;s completion<br /> first io_req_complete() puts one and then io_put_req_deferred() is<br /> called.