| Message ID | 20200731125109.18666-2-andr2000@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fixes and improvements for Xen pvdrm | expand |
On 31.07.20 14:51, Oleksandr Andrushchenko wrote: > From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> > > 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: 37ccb44d0b00 ("xen/gntdev: Implement dma-buf import functionality") I can't find this commit in the tree. Did you mean bf8dc55b1358? And don't you want to Cc stable for this patch, too? > > Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> Acked-by: Juergen Gross <jgross@suse.com> Juergen
On 8/4/20 9:11 AM, Jürgen Groß wrote: > On 31.07.20 14:51, Oleksandr Andrushchenko wrote: >> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> >> >> 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: 37ccb44d0b00 ("xen/gntdev: Implement dma-buf import functionality") > > I can't find this commit in the tree. Did you mean bf8dc55b1358? I'll double-check, thank you > > And don't you want to Cc stable for this patch, too? Hm, yes, sounds reasonable > >> >> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> > > Acked-by: Juergen Gross <jgross@suse.com> > > > Juergen
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);