From 043b1f185fb0f3939b7427f634787706f45411c4 Mon Sep 17 00:00:00 2001 From: Wang Ming Date: Thu, 13 Jul 2023 09:42:39 +0800 Subject: [PATCH 1/3] i40e: Fix an NULL vs IS_ERR() bug for debugfs_create_dir() The debugfs_create_dir() function returns error pointers. It never returns NULL. Most incorrect error checks were fixed, but the one in i40e_dbg_init() was forgotten. Fix the remaining error check. Fixes: 02e9c290814c ("i40e: debugfs interface") Signed-off-by: Wang Ming Tested-by: Pucha Himasekhar Reddy (A Contingent worker at Intel) Signed-off-by: Tony Nguyen --- drivers/net/ethernet/intel/i40e/i40e_debugfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/i40e/i40e_debugfs.c b/drivers/net/ethernet/intel/i40e/i40e_debugfs.c index 9954493cd448..62497f5565c5 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_debugfs.c +++ b/drivers/net/ethernet/intel/i40e/i40e_debugfs.c @@ -1839,7 +1839,7 @@ void i40e_dbg_pf_exit(struct i40e_pf *pf) void i40e_dbg_init(void) { i40e_dbg_root = debugfs_create_dir(i40e_driver_name, NULL); - if (!i40e_dbg_root) + if (IS_ERR(i40e_dbg_root)) pr_info("init of debugfs failed\n"); } From a2f054c10bef0b54600ec9cb776508443e941343 Mon Sep 17 00:00:00 2001 From: Jacob Keller Date: Mon, 10 Jul 2023 13:41:27 -0700 Subject: [PATCH 2/3] 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: fc2e6b3b132a ("iavf: Rework mutexes for better synchronisation") Signed-off-by: Jacob Keller Tested-by: Rafal Romanowski Signed-off-by: Tony Nguyen --- drivers/net/ethernet/intel/iavf/iavf_main.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c index 3a88d413ddee..939c8126eb43 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_main.c +++ b/drivers/net/ethernet/intel/iavf/iavf_main.c @@ -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); From 91896c8acce23d33ed078cffd46a9534b1f82be5 Mon Sep 17 00:00:00 2001 From: Jacob Keller Date: Mon, 10 Jul 2023 13:41:28 -0700 Subject: [PATCH 3/3] iavf: check for removal state before IAVF_FLAG_PF_COMMS_FAILED In iavf_adminq_task(), if the function can't acquire the adapter->crit_lock, it checks if the driver is removing. If so, it simply exits without re-enabling the interrupt. This is done to ensure that the task stops processing as soon as possible once the driver is being removed. However, if the IAVF_FLAG_PF_COMMS_FAILED is set, the function checks this before attempting to acquire the lock. In this case, the function exits early and re-enables the interrupt. This will happen even if the driver is already removing. Avoid this, by moving the check to after the adapter->crit_lock is acquired. This way, if the driver is removing, we will not re-enable the interrupt. Fixes: fc2e6b3b132a ("iavf: Rework mutexes for better synchronisation") Signed-off-by: Jacob Keller Tested-by: Rafal Romanowski Signed-off-by: Tony Nguyen --- drivers/net/ethernet/intel/iavf/iavf_main.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c index 939c8126eb43..9610ca770349 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_main.c +++ b/drivers/net/ethernet/intel/iavf/iavf_main.c @@ -3250,9 +3250,6 @@ static void iavf_adminq_task(struct work_struct *work) u32 val, oldval; u16 pending; - if (adapter->flags & IAVF_FLAG_PF_COMMS_FAILED) - goto out; - if (!mutex_trylock(&adapter->crit_lock)) { if (adapter->state == __IAVF_REMOVE) return; @@ -3261,6 +3258,9 @@ static void iavf_adminq_task(struct work_struct *work) goto out; } + if (adapter->flags & IAVF_FLAG_PF_COMMS_FAILED) + goto unlock; + event.buf_len = IAVF_MAX_AQ_BUF_SIZE; event.msg_buf = kzalloc(event.buf_len, GFP_KERNEL); if (!event.msg_buf)