kernel: smc: Fix use-after-free in tcp_write_timer_handler()

In the Linux kernel, the following vulnerability has been resolved: smc: Fix use-after-free in tcpwritetimerhandler. With Eric's ref tracker, syzbot finally found a repro for use-after-free in tcpwritetimerhandler by kernel TCP sockets. 0 If SMC creates a kernel socket in smccreate, the kernel...