tls: fix use-after-free on failed backlog decryption

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: tls: fix use-after-free on failed backlog decryption When the decrypt request goes to the backlog and crypto_aead_decrypt returns -EBUSY, tls_do_decryption will wait until all async decryptions have completed. If one of them fails, tls_do_decryption will return -EBADMSG and tls_decrypt_sg jumps to the error path, releasing all the pages. But the pages have been passed to the async callback, and have already been released by tls_decrypt_done. The only true async case is when crypto_aead_decrypt returns -EINPROGRESS. With -EBUSY, we already waited so we can tell tls_sw_recvmsg that the data is available for immediate copy, but we need to notify tls_decrypt_sg (via the new ->async_done flag) that the memory has already been released.

References

• https://git.kernel.org/stable/c/f2b85a4cc763841843de693bbd7308fe9a2c4c89
• https://git.kernel.org/stable/c/81be85353b0f5a7b660635634b655329b429eefe
• https://git.kernel.org/stable/c/1ac9fb84bc7ecd4bc6428118301d9d864d2a58d1
• https://git.kernel.org/stable/c/13114dc5543069f7b97991e3b79937b6da05f5b0