On 16/07/24 15:38, Kees Cook wrote:
With the new __counted_by annotation, the "lli_size" variable needs to
valid for accesses to the "lli" array. This requirement is not met in
stm32_dma3_chan_desc_alloc(), since "lli_size" starts at "0", so "lli"
index "0" will not be considered valid during the initialization for loop.
Fix this by setting lli_size immediately after allocation (similar to
how this is handled in stm32_mdma_alloc_desc() for the node/count
relationship).
Fixes: f561ec8b2b33 ("dmaengine: Add STM32 DMA3 support")
Signed-off-by: Kees Cook <kees@xxxxxxxxxx>
Reviewed-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
Thanks
--
Gustavo
---
Cc: "Amélie Delaunay" <amelie.delaunay@xxxxxxxxxxx>
Cc: Vinod Koul <vkoul@xxxxxxxxxx>
Cc: Maxime Coquelin <mcoquelin.stm32@xxxxxxxxx>
Cc: Alexandre Torgue <alexandre.torgue@xxxxxxxxxxx>
Cc: dmaengine@xxxxxxxxxxxxxxx
Cc: linux-stm32@xxxxxxxxxxxxxxxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
---
drivers/dma/stm32/stm32-dma3.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/dma/stm32/stm32-dma3.c b/drivers/dma/stm32/stm32-dma3.c
index 4087e0263a48..0be6e944df6f 100644
--- a/drivers/dma/stm32/stm32-dma3.c
+++ b/drivers/dma/stm32/stm32-dma3.c
@@ -403,6 +403,7 @@ static struct stm32_dma3_swdesc *stm32_dma3_chan_desc_alloc(struct stm32_dma3_ch
swdesc = kzalloc(struct_size(swdesc, lli, count), GFP_NOWAIT);
if (!swdesc)
return NULL;
+ swdesc->lli_size = count;
for (i = 0; i < count; i++) {
swdesc->lli[i].hwdesc = dma_pool_zalloc(chan->lli_pool, GFP_NOWAIT,
@@ -410,7 +411,6 @@ static struct stm32_dma3_swdesc *stm32_dma3_chan_desc_alloc(struct stm32_dma3_ch
if (!swdesc->lli[i].hwdesc)
goto err_pool_free;
}
- swdesc->lli_size = count;
swdesc->ccr = 0;
/* Set LL base address */
