From 63ed1e0287abcac9003e7b122badf546d66c9383 Mon Sep 17 00:00:00 2001 From: Souptick Joarder Date: Wed, 1 Jul 2020 11:47:41 +0530 Subject: [PATCH] staging: kpc2000: kpc_dma: Unpin partial pinned pages There is a bug, when get_user_pages() failed but partially pinned pages are not unpinned and positive numbers are returned instead of -ERRNO. Fixed it. Also, int is more appropriate type for rv. Changed it. Signed-off-by: Souptick Joarder Cc: John Hubbard Cc: Dan Carpenter Cc: Bharath Vedartham Link: https://lore.kernel.org/r/1593584264-16982-2-git-send-email-jrdr.linux@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/staging/kpc2000/kpc_dma/fileops.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/staging/kpc2000/kpc_dma/fileops.c b/drivers/staging/kpc2000/kpc_dma/fileops.c index 89753463e926..becdb41595ed 100644 --- a/drivers/staging/kpc2000/kpc_dma/fileops.c +++ b/drivers/staging/kpc2000/kpc_dma/fileops.c @@ -35,7 +35,7 @@ static int kpc_dma_transfer(struct dev_private_data *priv, unsigned long iov_base, size_t iov_len) { unsigned int i = 0; - long rv = 0; + int rv = 0; struct kpc_dma_device *ldev; struct aio_cb_data *acd; DECLARE_COMPLETION_ONSTACK(done); @@ -79,14 +79,14 @@ static int kpc_dma_transfer(struct dev_private_data *priv, rv = get_user_pages(iov_base, acd->page_count, FOLL_TOUCH | FOLL_WRITE | FOLL_GET, acd->user_pages, NULL); mmap_read_unlock(current->mm); /* release the semaphore */ if (rv != acd->page_count) { - dev_err(&priv->ldev->pldev->dev, "Couldn't get_user_pages (%ld)\n", rv); + dev_err(&priv->ldev->pldev->dev, "Couldn't get_user_pages (%d)\n", rv); goto err_get_user_pages; } // Allocate and setup the sg_table (scatterlist entries) rv = sg_alloc_table_from_pages(&acd->sgt, acd->user_pages, acd->page_count, iov_base & (PAGE_SIZE - 1), iov_len, GFP_KERNEL); if (rv) { - dev_err(&priv->ldev->pldev->dev, "Couldn't alloc sg_table (%ld)\n", rv); + dev_err(&priv->ldev->pldev->dev, "Couldn't alloc sg_table (%d)\n", rv); goto err_alloc_sg_table; } @@ -193,10 +193,15 @@ static int kpc_dma_transfer(struct dev_private_data *priv, put_page(acd->user_pages[i]); err_get_user_pages: + if (rv > 0) { + for (i = 0; i < rv; i++) + put_pages(acd->user_pages[i]); + rv = -EFAULT; + } kfree(acd->user_pages); err_alloc_userpages: kfree(acd); - dev_dbg(&priv->ldev->pldev->dev, "%s returning with error %ld\n", __func__, rv); + dev_dbg(&priv->ldev->pldev->dev, "%s returning with error %d\n", __func__, rv); return rv; }