CVE-2024-26800: tls: fix use-after-free on failed backlog decryption

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.

Classification

CVE ID: CVE-2024-26800

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.04% (probability of being exploited)

EPSS Percentile: 5.08% (scored less or equal to compared to others)

EPSS Date: 2025-02-04 (when was this score calculated)

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

Timeline