net/9p: Fix a potential socket leak in p9_socket_open

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: net/9p: Fix a potential socket leak in p9_socket_open Both p9_fd_create_tcp() and p9_fd_create_unix() will call p9_socket_open(). If the creation of p9_trans_fd fails, p9_fd_create_tcp() and p9_fd_create_unix() will return an error directly instead of releasing the cscoket, which will result in a socket leak. This patch adds sock_release() to fix the leak issue.

References

• https://git.kernel.org/stable/c/0396227f4daf4792a6a8aaa3b7771dc25c4cd443
• https://git.kernel.org/stable/c/ded893965b895b2dccd3d1436d8d3daffa23ea64
• https://git.kernel.org/stable/c/8b14bd0b500aec1458b51cb621c8e5fab3304260
• https://git.kernel.org/stable/c/2d24d91b9f44620824fc37b766f7cae00ca32748
• https://git.kernel.org/stable/c/e01c1542379fb395e7da53706df598f38905dfbf
• https://git.kernel.org/stable/c/8782b32ef867de7981bbe9e86ecb90e92e8780bd
• https://git.kernel.org/stable/c/aa08323fe18cb7cf95317ffa2d54ca1de8e74ebd
• https://git.kernel.org/stable/c/dcc14cfd7debe11b825cb077e75d91d2575b4cb8