Re: [PATCH 19/21] dmaengine: uniphier-xdmac: Annotate struct uniphier_xdmac_desc with __counted_by

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]


On 8/17/23 17:58, Kees Cook wrote:
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family

As found with Coccinelle[1], add __counted_by for struct uniphier_xdmac_desc.
Additionally, since the element count member must be set before accessing
the annotated flexible array member, move its initialization earlier.


Cc: Vinod Koul <vkoul@xxxxxxxxxx>
Cc: Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: dmaengine@xxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

Reviewed-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>


  drivers/dma/uniphier-xdmac.c | 6 +++---
  1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/uniphier-xdmac.c b/drivers/dma/uniphier-xdmac.c
index 290836b7e1be..dd51522879a7 100644
--- a/drivers/dma/uniphier-xdmac.c
+++ b/drivers/dma/uniphier-xdmac.c
@@ -80,7 +80,7 @@ struct uniphier_xdmac_desc {
  	unsigned int nr_node;
  	unsigned int cur_node;
  	enum dma_transfer_direction dir;
-	struct uniphier_xdmac_desc_node nodes[];
+	struct uniphier_xdmac_desc_node nodes[] __counted_by(nr_node);
struct uniphier_xdmac_chan {
@@ -295,6 +295,7 @@ uniphier_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst,
  	xd = kzalloc(struct_size(xd, nodes, nr), GFP_NOWAIT);
  	if (!xd)
  		return NULL;
+	xd->nr_node = nr;
for (i = 0; i < nr; i++) {
  		burst_size = min_t(size_t, len, XDMAC_MAX_WORD_SIZE);
@@ -309,7 +310,6 @@ uniphier_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst,
xd->dir = DMA_MEM_TO_MEM;
-	xd->nr_node = nr;
  	xd->cur_node = 0;
return vchan_tx_prep(vc, &xd->vd, flags);
@@ -351,6 +351,7 @@ uniphier_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
  	xd = kzalloc(struct_size(xd, nodes, sg_len), GFP_NOWAIT);
  	if (!xd)
  		return NULL;
+	xd->nr_node = sg_len;
for_each_sg(sgl, sg, sg_len, i) {
  		xd->nodes[i].src = (direction == DMA_DEV_TO_MEM)
@@ -385,7 +386,6 @@ uniphier_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
xd->dir = direction;
-	xd->nr_node = sg_len;
  	xd->cur_node = 0;
return vchan_tx_prep(vc, &xd->vd, flags);

[Index of Archives]     [Linux Kernel]     [Linux ARM (vger)]     [Linux ARM MSM]     [Linux Omap]     [Linux Arm]     [Linux Tegra]     [Fedora ARM]     [Linux for Samsung SOC]     [eCos]     [Linux PCI]     [Linux Fastboot]     [Gcc Help]     [Git]     [DCCP]     [IETF Announce]     [Security]     [Linux MIPS]     [Yosemite Campsites]

  Powered by Linux