[PATCH AUTOSEL 4.19 02/12] drm/amdkfd: Check for potential null return of kmalloc_array()

From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: QintaoShen <unSimple1993@163.com>,
	Alex Deucher <alexander.deucher@amd.com>,
	Sasha Levin <sashal@kernel.org>,
	Felix.Kuehling@amd.com, christian.koenig@amd.com,
	Xinhui.Pan@amd.com, airlied@linux.ie, daniel@ffwll.ch,
	amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org
Subject: [PATCH AUTOSEL 4.19 02/12] drm/amdkfd: Check for potential null return of kmalloc_array()
Date: Mon, 11 Apr 2022 20:51:35 -0400	[thread overview]
Message-ID: <20220412005148.351391-2-sashal@kernel.org> (raw)
In-Reply-To: <20220412005148.351391-1-sashal@kernel.org>

From: QintaoShen <unSimple1993@163.com>

[ Upstream commit ebbb7bb9e80305820dc2328a371c1b35679f2667 ]

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>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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 e9f0e0a1b41c..892077377339 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_events.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_events.c
@@ -532,6 +532,8 @@ 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);
-- 
2.35.1

