[PATCH AUTOSEL 5.6 122/149] dmaengine: idxd: check return result from check_vma() in cdev

From: Sasha Levin
Date: Sat Apr 11 2020 - 19:43:24 EST


From: Dave Jiang <dave.jiang@xxxxxxxxx>

[ Upstream commit b391554c61cb353c279523a706734b090aaf9000 ]

The returned result from the check_vma() function in the cdev ->mmap() call
needs to be handled. Add the check and returning error.

Fixes: 42d279f9137a ("dmaengine: idxd: add char driver to expose submission portal to userland")
Reported-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Link: https://lore.kernel.org/r/158264926659.9387.14325163515683047959.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/dma/idxd/cdev.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/dma/idxd/cdev.c b/drivers/dma/idxd/cdev.c
index 989b7a25ca614..677ccbe6261f4 100644
--- a/drivers/dma/idxd/cdev.c
+++ b/drivers/dma/idxd/cdev.c
@@ -139,6 +139,8 @@ static int idxd_cdev_mmap(struct file *filp, struct vm_area_struct *vma)

dev_dbg(&pdev->dev, "%s called\n", __func__);
rc = check_vma(wq, vma, __func__);
+ if (rc < 0)
+ return rc;

vma->vm_flags |= VM_DONTCOPY;
pfn = (base + idxd_get_wq_portal_full_offset(wq->id,
--
2.20.1