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From:   QintaoShen <unSimple1993@163.com>
To:     Felix.Kuehling@amd.com
Cc:     amd-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        QintaoShen <unSimple1993@163.com>
Subject: [PATCH v1] drm/amdkfd: Check for potential null return of kmalloc_array()
Date:   Thu, 24 Mar 2022 16:26:23 +0800
Message-Id: <1648110383-3533-1-git-send-email-unSimple1993@163.com>
Precedence: bulk

As the kmalloc_array() may return null, the 'event_waiters[i].wait' would lead to null-pointer dereference.
Therefore, it is better to check the return value of kmalloc_array() to avoid this confusion.

Signed-off-by: QintaoShen <unSimple1993@163.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_events.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_events.c b/drivers/gpu/drm/amd/amdkfd/kfd_events.c
index deeccce..64f4a51 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_events.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_events.c
@@ -749,6 +749,8 @@ static struct kfd_event_waiter *alloc_event_waiters(uint32_t num_events)
 	event_waiters = kmalloc_array(num_events,
 					sizeof(struct kfd_event_waiter),
 					GFP_KERNEL);
+	if (!event_waiters)
+		return NULL;
 
 	for (i = 0; (event_waiters) && (i < num_events) ; i++) {
 		init_wait(&event_waiters[i].wait);
-- 
2.7.4