From: Charles Keepax Date: Mon, 17 Nov 2014 09:14:31 +0000 (+0000) Subject: spi: Fix mapping from vmalloc-ed buffer to scatter list X-Git-Tag: v3.17.5~36 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2f5dbae2894829b607ac5c0558e3ae0b34f8a8c7;p=thirdparty%2Fkernel%2Fstable.git spi: Fix mapping from vmalloc-ed buffer to scatter list commit c1aefbdd050e1fb15e92bcaf34d95b17ea952097 upstream. We can only use page_address on memory that has been mapped using kmap, when the buffer passed to the SPI has been allocated by vmalloc the page has not necessarily been mapped through kmap. This means sometimes page_address will return NULL causing the pointer we pass to sg_set_buf to be invalid. As we only call page_address so that we can pass a virtual address to sg_set_buf which will then immediately call virt_to_page on it, fix this by calling sg_set_page directly rather then relying on the sg_set_buf helper. Signed-off-by: Charles Keepax Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index ca935df80c88e..2bf2dfa609dd7 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -609,13 +609,13 @@ static int spi_map_buf(struct spi_master *master, struct device *dev, sg_free_table(sgt); return -ENOMEM; } - sg_buf = page_address(vm_page) + - ((size_t)buf & ~PAGE_MASK); + sg_set_page(&sgt->sgl[i], vm_page, + min, offset_in_page(buf)); } else { sg_buf = buf; + sg_set_buf(&sgt->sgl[i], sg_buf, min); } - sg_set_buf(&sgt->sgl[i], sg_buf, min); buf += min; len -= min;