From: Yu'an Wang <wangyuan46@huawei.com> driver inclusion category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5VVP6 CVE: NA -------------------------------- The device driver pointer will be set null during hot plugging. So should use the device driver null check to pretect put queue. Otherwise the null pointer may cause the oom ops as doing hot plugging. Signed-off-by: Yu'an Wang <wangyuan46@huawei.com> Reviewed-by: Kai Ye <yekai13@huawei.com> Reviewed-by: Longfang Liu <liulongfang@huawei.com> Reviewed-by: li yongxin <liyongxin1@huawei.com> Signed-off-by: Laibin Qiu <qiulaibin@huawei.com> --- drivers/misc/uacce/uacce.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/misc/uacce/uacce.c b/drivers/misc/uacce/uacce.c index b0cdc244e882..dc3aaae30752 100644 --- a/drivers/misc/uacce/uacce.c +++ b/drivers/misc/uacce/uacce.c @@ -229,10 +229,8 @@ static void uacce_free_dma_buffers(struct uacce_queue *q) return; while (i < qfr->dma_list[0].total_num) { WARN_ON(!qfr->dma_list[i].size || !qfr->dma_list[i].dma); - dev_dbg(uacce->pdev, "free dma qfr %s (kaddr=%lx, dma=%llx)\n", - uacce_qfrt_str(qfr), - (unsigned long)qfr->dma_list[i].kaddr, - qfr->dma_list[i].dma); + dev_dbg(uacce->pdev, "free dma qfr %s (index = %d)\n", + uacce_qfrt_str(qfr), i); dma_free_coherent(uacce->pdev, qfr->dma_list[i].size, qfr->dma_list[i].kaddr, qfr->dma_list[i].dma); @@ -383,8 +381,8 @@ static int uacce_mmap_dma_buffers(struct uacce_queue *q, slice[i].size); if (ret) { dev_err(uacce->pdev, - "mmap dma buf fail(dma=0x%llx,size=0x%x)!\n", - slice[i].dma, slice[i].size); + "mmap dma buf fail(dma index=%d,size=0x%x)!\n", + i, slice[i].size); goto DMA_MMAP_FAIL; } @@ -736,6 +734,12 @@ static void uacce_put_queue(struct uacce_queue *q) q->state = UACCE_Q_ZOMBIE; q->filep->private_data = NULL; uacce_queue_drain(q); + + if (!uacce->pdev->driver) { + dev_warn(uacce->pdev, "the parent device is hot plugged!\n"); + return; + } + if (module_refcount(uacce->pdev->driver->owner) > 0) module_put(uacce->pdev->driver->owner); } -- 2.25.1