In the Linux kernel, the following vulnerability has been resolved: net/tls: fix use-after-free in -EBUSY error path of tls_do_encryption The -EBUSY handling in tls_do_encryption(), introduced by commit 859054147318 ("net: tls: handle backlogging of crypto requests"), has a use-after-free due to double cleanup of encrypt_pending and the scatterlist entry. When crypto_aead_encrypt() returns -EBUSY, the request is enqueued to the cryptd backlog and the async callback tls_encrypt_done() will be invoked upon completion. That callback unconditionally restores the scatterlist entry (sge->offset, sge->length) and decrements ctx->encrypt_pending. However, if tls_encrypt_async_wait() returns an error, the synchronous error path in tls_do_encryption() performs the same cleanup again, double-decrementing encrypt_pending and double-restoring the scatterlist. The double-decrement corrupts the encrypt_pending sentinel (initialized to 1), making tls_encrypt_async_wait() permanently skip the wait for pending async callbacks. A subsequent sendmsg can then free the tls_rec via bpf_exec_tx_verdict() while a cryptd callback is still pending, resulting in a use-after-free when the callback fires on the freed record. Fix this by skipping the synchronous cleanup when the -EBUSY async wait returns an error, since the callback has already handled encrypt_pending and sge restoration.
| Vendor | Product | Versions |
|---|---|---|
| linux | linux_kernel | 3ade391adc584f17b5570fd205de3ad029090368, cd1bbca03f3c1d845ce274c0d0a66de8e5929f72, 13eca403876bbea3716e82cdfe6f1e6febb38754, 8590541473188741055d27b955db0777569438e3, 8590541473188741055d27b955db0777569438e3, 8590541473188741055d27b955db0777569438e3, 8590541473188741055d27b955db0777569438e3, ab6397f072e5097f267abf5cb08a8004e6b17694, 5.15.160, 6.1.84, 6.6.18, 6.7.6, 6.8 |
Downstream vendors/products affected by this vulnerability
| Vendor | Product | Source | Confidence |
|---|---|---|---|
| linux | linux | mitre_affected | 90% |
| open source | linux kernel | cert_advisory | 90% |
Updated severity to HIGH and marked the vulnerability as exploit available and actively exploited.
Updated severity to CRITICAL, added affected version 6.19.12, and corrected exploit availability to false.
Initial creation
