Commit a2f054c1 authored by Jacob Keller's avatar Jacob Keller Committed by Tony Nguyen
Browse files

iavf: fix potential deadlock on allocation failure 



In iavf_adminq_task(), if kzalloc() fails to allocate the event.msg_buf,
the function will exit without releasing the adapter->crit_lock.

This is unlikely, but if it happens, the next access to that mutex will
deadlock.

Fix this by moving the unlock to the end of the function, and adding a new
label to allow jumping to the unlock portion of the function exit flow.

Fixes: fc2e6b3b ("iavf: Rework mutexes for better synchronisation")
Signed-off-by: default avatarJacob Keller <jacob.e.keller@intel.com>
Tested-by: default avatarRafal Romanowski <rafal.romanowski@intel.com>
Signed-off-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
parent 043b1f18

drivers/net/ethernet/intel/iavf/iavf_main.c

+3 −2
Original line number Diff line number Diff line
@@ -3264,7 +3264,7 @@ static void iavf_adminq_task(struct work_struct *work) 
	event.buf_len = IAVF_MAX_AQ_BUF_SIZE;

	event.msg_buf = kzalloc(event.buf_len, GFP_KERNEL);

	if (!event.msg_buf)

		goto out;

		goto unlock;



	do {

		ret = iavf_clean_arq_element(hw, &event, &pending);
@@ -3279,7 +3279,6 @@ static void iavf_adminq_task(struct work_struct *work) 
		if (pending != 0)

			memset(event.msg_buf, 0, IAVF_MAX_AQ_BUF_SIZE);

	} while (pending);

	mutex_unlock(&adapter->crit_lock);



	if (iavf_is_reset_in_progress(adapter))

		goto freedom;
@@ -3323,6 +3322,8 @@ static void iavf_adminq_task(struct work_struct *work) 


freedom:

	kfree(event.msg_buf);

unlock:

	mutex_unlock(&adapter->crit_lock);

out:

	/* re-enable Admin queue interrupt cause */

	iavf_misc_irq_enable(adapter);