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| author | Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> | 2020-08-13 08:21:09 +0200 |
|---|---|---|
| committer | Juergen Gross <jgross@suse.com> | 2020-08-13 12:50:22 +0200 |
| commit | 5fa4e6f1c2d8c9a4e47e1931b42893172d388f2b (patch) | |
| tree | 88ff3e420ef0fae924ee6bb9adf3f8d79051e704 | |
| parent | x86/xen: drop tests for highmem in pv code (diff) | |
| download | linux-5fa4e6f1c2d8c9a4e47e1931b42893172d388f2b.tar.xz linux-5fa4e6f1c2d8c9a4e47e1931b42893172d388f2b.zip | |
xen/gntdev: Fix dmabuf import with non-zero sgt offset
It is possible that the scatter-gather table during dmabuf import has
non-zero offset of the data, but user-space doesn't expect that.
Fix this by failing the import, so user-space doesn't access wrong data.
Fixes: bf8dc55b1358 ("xen/gntdev: Implement dma-buf import functionality")
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Acked-by: Juergen Gross <jgross@suse.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200813062113.11030-2-andr2000@gmail.com
Signed-off-by: Juergen Gross <jgross@suse.com>
| -rw-r--r-- | drivers/xen/gntdev-dmabuf.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/xen/gntdev-dmabuf.c b/drivers/xen/gntdev-dmabuf.c index 75d3bb948bf3..b1b6eebafd5d 100644 --- a/drivers/xen/gntdev-dmabuf.c +++ b/drivers/xen/gntdev-dmabuf.c @@ -613,6 +613,14 @@ dmabuf_imp_to_refs(struct gntdev_dmabuf_priv *priv, struct device *dev, goto fail_detach; } + /* Check that we have zero offset. */ + if (sgt->sgl->offset) { + ret = ERR_PTR(-EINVAL); + pr_debug("DMA buffer has %d bytes offset, user-space expects 0\n", + sgt->sgl->offset); + goto fail_unmap; + } + /* Check number of pages that imported buffer has. */ if (attach->dmabuf->size != gntdev_dmabuf->nr_pages << PAGE_SHIFT) { ret = ERR_PTR(-EINVAL); |