From: Hangyu Hua hbh25y@gmail.com

commit 49c47cc21b5b7a3d8deb18fc57b0aa2ab1286962 upstream.

ctx->crypto_send.info is not protected by lock_sock in do_tls_getsockopt_conf(). A race condition between do_tls_getsockopt_conf() and error paths of do_tls_setsockopt_conf() may lead to a use-after-free or null-deref.

More discussion: https://lore.kernel.org/all/Y/ht6gQL+u6fj3dG@hog/

Fixes: 3c4d7559159b ("tls: kernel TLS support") Signed-off-by: Hangyu Hua hbh25y@gmail.com Link: https://lore.kernel.org/r/20230228023344.9623-1-hbh25y@gmail.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Meena Shanmugam meenashanmugam@google.com --- net/tls/tls_main.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c index a947cfb100bd..abd0c4557cb9 100644 --- a/net/tls/tls_main.c +++ b/net/tls/tls_main.c @@ -386,13 +386,11 @@ static int do_tls_getsockopt_conf(struct sock *sk, char __user *optval, rc = -EINVAL; goto out; } - lock_sock(sk); memcpy(crypto_info_aes_gcm_128->iv, cctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, TLS_CIPHER_AES_GCM_128_IV_SIZE); memcpy(crypto_info_aes_gcm_128->rec_seq, cctx->rec_seq, TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE); - release_sock(sk); if (copy_to_user(optval, crypto_info_aes_gcm_128, sizeof(*crypto_info_aes_gcm_128))) @@ -410,13 +408,11 @@ static int do_tls_getsockopt_conf(struct sock *sk, char __user *optval, rc = -EINVAL; goto out; } - lock_sock(sk); memcpy(crypto_info_aes_gcm_256->iv, cctx->iv + TLS_CIPHER_AES_GCM_256_SALT_SIZE, TLS_CIPHER_AES_GCM_256_IV_SIZE); memcpy(crypto_info_aes_gcm_256->rec_seq, cctx->rec_seq, TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE); - release_sock(sk); if (copy_to_user(optval, crypto_info_aes_gcm_256, sizeof(*crypto_info_aes_gcm_256))) @@ -436,6 +432,8 @@ static int do_tls_getsockopt(struct sock *sk, int optname, { int rc = 0;

+ lock_sock(sk); + switch (optname) { case TLS_TX: case TLS_RX: @@ -446,6 +444,9 @@ static int do_tls_getsockopt(struct sock *sk, int optname, rc = -ENOPROTOOPT; break; } + + release_sock(sk); + return rc; }