From: Arthur Kiyanovski akiyano@amazon.com
[ Upstream commit c207979f5ae10ed70aff1bb13f39f0736973de99 ]
comp_ctx can be NULL in a very rare case when an admin command is executed during the execution of ena_remove().
The bug scenario is as follows:
* ena_destroy_device() sets the comp_ctx to be NULL * An admin command is executed before executing unregister_netdev(), this can still happen because our device can still receive callbacks from the netdev infrastructure such as ethtool commands. * When attempting to access the comp_ctx, the bug occurs since it's set to NULL
Fix: Added a check that comp_ctx is not NULL
Fixes: 1738cd3ed342 ("net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)") Signed-off-by: Sameeh Jubran sameehj@amazon.com Signed-off-by: Arthur Kiyanovski akiyano@amazon.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/amazon/ena/ena_com.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/net/ethernet/amazon/ena/ena_com.c b/drivers/net/ethernet/amazon/ena/ena_com.c index 397fb49156a9a..d52ab752b37f1 100644 --- a/drivers/net/ethernet/amazon/ena/ena_com.c +++ b/drivers/net/ethernet/amazon/ena/ena_com.c @@ -201,6 +201,11 @@ static inline void comp_ctxt_release(struct ena_com_admin_queue *queue, static struct ena_comp_ctx *get_comp_ctxt(struct ena_com_admin_queue *queue, u16 command_id, bool capture) { + if (unlikely(!queue->comp_ctx)) { + pr_err("Completion context is NULL\n"); + return NULL; + } + if (unlikely(command_id >= queue->q_depth)) { pr_err("command id is larger than the queue size. cmd_id: %u queue size %d\n", command_id, queue->q_depth);