WSL2-Linux-Kernel/net/tls
Liu Jian 481bd6dcc5 net/tls: do not free tls_rec on async operation in bpf_exec_tx_verdict()
[ Upstream commit cfaa80c91f ]

I got the below warning when do fuzzing test:
BUG: KASAN: null-ptr-deref in scatterwalk_copychunks+0x320/0x470
Read of size 4 at addr 0000000000000008 by task kworker/u8:1/9

CPU: 0 PID: 9 Comm: kworker/u8:1 Tainted: G           OE
Hardware name: linux,dummy-virt (DT)
Workqueue: pencrypt_parallel padata_parallel_worker
Call trace:
 dump_backtrace+0x0/0x420
 show_stack+0x34/0x44
 dump_stack+0x1d0/0x248
 __kasan_report+0x138/0x140
 kasan_report+0x44/0x6c
 __asan_load4+0x94/0xd0
 scatterwalk_copychunks+0x320/0x470
 skcipher_next_slow+0x14c/0x290
 skcipher_walk_next+0x2fc/0x480
 skcipher_walk_first+0x9c/0x110
 skcipher_walk_aead_common+0x380/0x440
 skcipher_walk_aead_encrypt+0x54/0x70
 ccm_encrypt+0x13c/0x4d0
 crypto_aead_encrypt+0x7c/0xfc
 pcrypt_aead_enc+0x28/0x84
 padata_parallel_worker+0xd0/0x2dc
 process_one_work+0x49c/0xbdc
 worker_thread+0x124/0x880
 kthread+0x210/0x260
 ret_from_fork+0x10/0x18

This is because the value of rec_seq of tls_crypto_info configured by the
user program is too large, for example, 0xffffffffffffff. In addition, TLS
is asynchronously accelerated. When tls_do_encryption() returns
-EINPROGRESS and sk->sk_err is set to EBADMSG due to rec_seq overflow,
skmsg is released before the asynchronous encryption process ends. As a
result, the UAF problem occurs during the asynchronous processing of the
encryption module.

If the operation is asynchronous and the encryption module returns
EINPROGRESS, do not free the record information.

Fixes: 635d939817 ("net/tls: free record only on encryption error")
Signed-off-by: Liu Jian <liujian56@huawei.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://lore.kernel.org/r/20230909081434.2324940-1-liujian56@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-19 12:23:04 +02:00
..
Kconfig net/tls: Select SOCK_RX_QUEUE_MAPPING from TLS_DEVICE 2021-02-11 19:08:06 -08:00
Makefile net/tls: add skeleton of MIB statistics 2019-10-05 16:29:00 -07:00
tls_device.c net: tls: avoid discarding data on record close 2023-08-26 14:23:22 +02:00
tls_device_fallback.c net/tls: Fix use-after-free after the TLS device goes down and up 2021-06-01 15:58:05 -07:00
tls_main.c net: deal with most data-races in sk_wait_event() 2023-05-24 17:36:42 +01:00
tls_proc.c net: fix proc_fs init handling in af_packet and tls 2020-12-14 19:39:30 -08:00
tls_sw.c net/tls: do not free tls_rec on async operation in bpf_exec_tx_verdict() 2023-09-19 12:23:04 +02:00
tls_toe.c net/tls: rename tls_hw_* functions tls_toe_* 2019-10-04 14:07:07 -07:00
trace.c net/tls: add tracing for device/offload events 2019-10-05 16:29:00 -07:00
trace.h net/tls: add device decrypted trace point 2019-10-05 16:29:00 -07:00