From: Jacob Keller <jacob.e.keller@intel.com>
Date: Mon, 10 Jul 2023 13:41:27 -0700
Subject: [PATCH] iavf: fix potential deadlock on allocation failure
References: bsc#1012628
Patch-mainline: 6.4.8
Git-commit: a2f054c10bef0b54600ec9cb776508443e941343
[ Upstream commit a2f054c10bef0b54600ec9cb776508443e941343 ]
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 <jacob.e.keller@intel.com>
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
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 ba96312f..6c25d240 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -3300,7 +3300,7 @@ 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);
@@ -3315,7 +3315,6 @@ 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;
@@ -3359,6 +3358,8 @@ 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);
--
2.35.3