This is a note to let you know that I've just added the patch titled net/tls: Remove the context from the list in tls_device_down to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-tls-remove-the-context-from-the-list-in-tls_devi.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e1bf6422281150d1b6fb11cbaeb4d17c644404c8 Author: Maxim Mikityanskiy <maximmi@xxxxxxxxxx> Date: Thu Jul 21 12:11:27 2022 +0300 net/tls: Remove the context from the list in tls_device_down [ Upstream commit f6336724a4d4220c89a4ec38bca84b03b178b1a3 ] tls_device_down takes a reference on all contexts it's going to move to the degraded state (software fallback). If sk_destruct runs afterwards, it can reduce the reference counter back to 1 and return early without destroying the context. Then tls_device_down will release the reference it took and call tls_device_free_ctx. However, the context will still stay in tls_device_down_list forever. The list will contain an item, memory for which is released, making a memory corruption possible. Fix the above bug by properly removing the context from all lists before any call to tls_device_free_ctx. Fixes: 3740651bf7e2 ("tls: Fix context leak on tls_device_down") Signed-off-by: Maxim Mikityanskiy <maximmi@xxxxxxxxxx> Reviewed-by: Tariq Toukan <tariqt@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c index 4e33150cfb9e..cf75969375cf 100644 --- a/net/tls/tls_device.c +++ b/net/tls/tls_device.c @@ -1351,8 +1351,13 @@ static int tls_device_down(struct net_device *netdev) * by tls_device_free_ctx. rx_conf and tx_conf stay in TLS_HW. * Now release the ref taken above. */ - if (refcount_dec_and_test(&ctx->refcount)) + if (refcount_dec_and_test(&ctx->refcount)) { + /* sk_destruct ran after tls_device_down took a ref, and + * it returned early. Complete the destruction here. + */ + list_del(&ctx->list); tls_device_free_ctx(ctx); + } } up_write(&device_offload_lock);